Blender

# Knowing before Making

Blender is a powerful and complex 3D modeling and rendering package. Before you can use it effectively to make things, you need to know a few things about how it works:

• the process of 3D modeling and rendering (what Blender does)
• some rudiments of 3D analytic geometry (axes and coordinates)
• orthographic and perspective views of a 3D object
• local coordinate systems and child objects
• the fundamentals of Blender's user interface (hotkeys, windows, and menus)
• how to view a 3D scene from different vantage points (in Blender)

This unit is devoted entirely to this sort of background knowledge. You won't create your first Blender model until the next unit.

Knowing this, you might be tempted to skip ahead. Depending on your background, that may or may not work. For instance, if you've used other 3D graphics packages, you might be able to skim (or skip) ahead as far as the user interface tutorial. But if there's any doubt, please proceed through the tutorials in sequence.

Blender is not the kind of software you can launch into and grope about until you find your way. It's not like exploring an unfamiliar city. It's more like flying a spaceship. If you hop into the pilot's seat without knowing the fundamentals, you'll be lucky to ever get off the ground, and it'd take a miracle for you to reach your destination safely.

Like any subject, 3D modeling has its own jargon: terminology specific to the subject and ordinary words that have special meanings in the context of computer graphics.

In this book, important new words are highlighted on first appearance and defined soon after. If you suspect you've missed (or forgotten) the meaning of a word, try looking it up in the Glossary.

### Things You'll Need

Depending on what is installed on your system, you may also need the appropriate Python installation. Each version of Blender works with only one specific version of Python, which is generally included in the download.

Blender version Python version
2.49 2.6
2.5x 3.2
2.6 3.3
2.76 3.4
2.77 3.5
2.78 3.5
Installation instructions

Since Blender is open-source software, you can download the source code and build it yourself, but it's easier to download a pre-built install package. Install packages are provided for each supported operating system:

• Microsoft Windows (32-bit and 64-bit)
• Linux (32-bit and 64-bit x86)
• Apple Mac OS X (PowerPC and Intel)
• FreeBSD (32-bit and 64 bit)
• Solaris
• Irix

Many Linux distributions have Blender available in their package repositories, though it may be a slightly older version. You can use your system's package manager to download and install the package.

Windows users get to choose between an executable installer ("setup wizard") and a ZIP archive.

After the installation process is finished, Blender should appear in the Graphics section of your desktop environment application menu.

You may also want to download a 2D image editor, such as GIMP ([1]), Paint.NET ([2]), or Photoshop. For viewing video files, you may want to install VLC ([3]) media player.

It's a good idea to have pencil and paper handy for sketching and taking notes. There's a lot to absorb. Taking notes as you go will pay dividends later.

### Where to Go for Help

If you get stuck, you can ask for help from other Blender users in the appendices.

Many modules have a section like this at the bottom, listing websites with information on the topics covered in the module.

# What Blender Can Do

In this module, you'll learn what Blender does, both in terms of the product (images) and the process (3D modeling).

Blender is a free software package for authoring "three-dimensional" (3D) graphics (also known as computer graphics or “CG”), including still images, games, and video.

While the end-product of most Blender projects is a two-dimensional (2D) raster image on a flat surface (be it a monitor, movie screen, or sheet of paper) except for Head Mounted Virtual Reality applications, the images are said to be "3D" because they exhibit the illusion of depth. In other words, someone looking at the image can easily tell which parts are meant to be closer and which are farther away.

## An Example

Here's a realistic still image that was authored with Blender.

"A Lonely House", by Mayqel

Look closely at the building.

• Because it is obscured by the building, you can tell that the tree-lined hillside is behind the building instead of vice versa.
• The way the top and bottom edges of the front wall appear to converge toward the base of the tree allow you to judge the angle between the front wall and your viewpoint.
• Your brain interprets dark portions of the wall as shadows, allowing you to estimate where the light is coming from, even though the sun is outside the frame of the image.

While an illusion of depth can be authored by hand with 2D graphics software (or a paintbrush!), Blender provides a much easier way.

It's likely that the lonely house never existed outside of the artist's mind. Instead of building a big set on a rural lot in Germany, waiting for the right light, and photographing it, the author built a scene in a virtual 3D world—one contained inside a computer. This is called CGI (Computer Generated Imagery). He or she then used Blender to render the scene (convert it into a 2D image). You can view more of what Blender can do at the Blender gallery: http://www.blender.org/features/

## Steps in the 3D Production Process

To produce an image like the one above involves two major steps to start with:

• Modelling, which is the creation of your miniature 3D world, also known as a model or scene. This involves defining the geometry of the objects, making it look like they are made out of particular materials, setting up the lighting, and defining a camera viewpoint.
• Rendering, which is the actual generation of the image of the world from the viewpoint of the camera (taking a “photograph” of the scene, if you like), for your audience to enjoy.

3D is often used to produce not just single still images, but animations as well. This requires some additional steps:

• Rigging — setting up a rig, namely a way of deforming (changing the shape of) a character in various repeatable ways to convincingly mimic joint movements, facial expressions and other such actions of real-life people or animals.
• Posing — choreographing the positions of the objects and their parts in the 3D scene over time, using the previously-created animation rigs
• Rendering now involves creating a whole sequence of frames representing movement over time, rather than just a single still frame.

But that’s not all. There are frequently additional processes to embellish the results of the above, to make them look more realistic:

• Sculpting — a more organic form of modelling objects by shaping them as though they were made out of clay. This produces more complicated, irregular shapes which mimic real objects found in nature, as opposed to clean, simple, geometrical ones which mostly only exist in the world of mathematics.
• Texture painting — You’re probably familiar with programs that let you paint an image on a 2D digital canvas. Such programs are commonly used in 3D production, to create textures which are “wrapped” around the surfaces of 3D objects to give them a more interesting appearance. 3D programs also often allow direct painting on the surfaces of those objects, so the effect of the design can be observed immediately, instead of having to go through a separate paint-on-a-flat-surface-then-wrap sequence of steps.
• Physical modelling — simulating the behaviour of real-world objects subject to real-world forces, for example hard balls colliding, soft cloth draping itself over an obstacle under gravity, water flowing and pouring. Mathematical formulas are available for these that give results very close to real life, all you need is the computing power to calculate them.
• Motion capture, or mocap: producing convincing animations, particularly ones that look like the movements of real people (walking, running, dancing etc) can be hard. Hence the technique of capturing the motions of live actors, by filming them with special markers attached to strategic points on their bodies, and doing computer processing to track the movements of these markers and convert them to corresponding movements of an animation rig.
• Compositing — this is where 3D renders are merged together with real photographic/live-action footage, to make it look like a rendered model is in the middle of a real-world scene, or conversely a real live actor is in the middle of a rendered scene. If done with proper skill, in particular due care to matching the effects of lights and shadows, the viewer becomes unable to tell what is real and what is not!

And just to add another complication to the mix, there are two kinds of rendering:

• Real-time rendering is rendering that has to happen under tight time constraints, typically for interactive applications like video gaming. For example, most gamers nowadays consider that the screen has to be updated 60 times per second in order to render smooth motion and respond quickly enough to player actions. These time constraints impose major limitations on the kinds of rendering techniques that can be used.
• Non-real-time rendering is where the time constraints are not so tight, and quality is the overriding factor. For example, when producing a single still frame, it may not matter so much that it takes minutes or hours to do so, because the beauty and detail of the final image is worth it. When rendering a Hollywood-quality movie, it may still take hours per frame, but the use of a renderfarm of hundreds or thousands of machines, all working on different frames at the same time, allows the entire sequence to complete in just a few weeks.

But wait, there’s more: There are also some areas, which might be considered to be stepping outside of traditional 3D production work, where Blender provides functionality:

• Video editing — having rendered your animation sequences and shot your live-action footage, you will want to combine them in a properly-timed linear sequence to tell a coherent story.
• 3D printing — Though still in its early days yet, many people are already experimenting with creating objects using 3D printers. The shape data may be obtained from real objects with 3D scanning, or it may be created from scratch using 3D modelling, or you can even combine both processes.

Blender is a capable tool for every single one of these processes. There’s quite a lot there, isn’t there? But don’t be too intimidated: this Wikibook will take things step by step, and you will be able to produce some fun stuff from early on.

# 3D Geometry

If you haven't previously studied 3D graphics, technical drawing, or analytic geometry, you are about to learn a new way of visualizing the world, an ability that's fundamental to working with Blender or any 3D modeling tool.

3D modeling is based on geometry, the branch of mathematics concerned with spatial relationships, specifically analytical geometry, which expresses these relationships in terms of algebraic formulas. If you have studied geometry, some of the terminology will be familiar.

## Coordinates And Coordinate Systems

Look around the room you’re in. The odds are it will have a cuboidal shape, with four vertical walls at right angles to each other, a flat, horizontal floor, and a flat, horizontal ceiling.

Now imagine there’s a fly buzzing around the room. The fly is moving in three-dimensional space. In mathematical terms, that means its position within the room at any given moment, can be expressed in terms of a unique combination of three numbers.

There are an infinite number of ways —coordinate systems— in which we could come up with a convention for defining and measuring these numbers, i.e. the coordinates. Each convention will yield different values even if the fly is in the same position. Coordinates only make sense with reference to a specific coordinate system! To narrow down the possibilities (in a purely arbitrary fashion), let us label the walls of the room with the points of the compass: in a clockwise direction, North, East, South and West. (If you know which way really is north, feel free to use that to label the walls of your room. Otherwise, choose any wall you like as north.)

Consider the point at floor level in the south-west corner of the room. We will call this (arbitrary) point the origin of our coordinate system, and the three numbers at this point will be ${\displaystyle (0,0,0)}$. The first of the three numbers will be the distance (in some suitable units, let’s say meters) eastwards from the west wall, the second number will be the distance north from the south wall, and the third number will be the height above the floor.

Each of these directions is called an axis (plural: axes), and they are conventionally labelled X, Y and Z, in that order. With a little bit of thought, you should be able to convince yourself that every point within the space of your room corresponds to exactly one set of ${\displaystyle (x,y,z)}$ values. And conversely that every possible combination of ${\displaystyle (x,y,z)}$ values, with ${\displaystyle 0\leq x\leq W}$, ${\displaystyle 0\leq y\leq L}$ and ${\displaystyle 0\leq z\leq H}$ (where ${\displaystyle W}$ is the east-west dimension of your room, ${\displaystyle L}$ is its north-south dimension, and ${\displaystyle H}$ is the height between ceiling and floor) corresponds to a point in the room.

The following diagram illustrates how the coordinates are built up, using the same colour codes that Blender uses to label its axes: red for X, green for Y and blue for Z (an easy way to remember this if you're familiar with RGB is the order -- Red X, Green Y, Blue Z). In the second picture, the x value defines a plane parallel to the west wall of the room. In the third picture, the y value defines a plane parallel to the south wall, and in the fourth picture, the z value defines a plane parallel to the floor. Put the planes together in the fifth picture, and they intersect at a unique point.

This style of coordinate system, with the numbers corresponding to distances along perpendicular axes, is called Cartesian coordinates, named after René Descartes, the 17th-century mathematician who first introduced the concept. Legend has it that he came up with the idea after watching a fly buzzing around his bedroom!

There are other ways to define coordinate systems, for example by substituting direction angles in place of one or two of the distance measurements. These can be useful in certain situations, but usually all coordinate systems in Blender are Cartesian. However, in Blender, switching between these coordinate systems is simple and easy to do.

### Negative Coordinates

Can coordinate values be negative? Depending on the situation, yes. Here we are only considering points within our room. But suppose instead of placing our origin in the bottom southwest corner, we put it in the middle of the room, halfway between the floor and ceiling. (After all, it is an arbitrary point, we can place it wherever we like, as long as we agree on its location.) If the X-coordinate is the distance east from the origin, how do we define a point west of the origin? We simply give it a negative X-coordinate. Similarly, points north of the origin have a positive Y-coordinate, those south of it, have negative Y-coordinates. Points above the origin have a positive Z-coordinate, those below it, a negative Z-coordinate.

### Handedness Of Coordinate Systems

It is conventional for most Cartesian coordinate systems to be right-handed. To understand this, hold the thumb, index finger and middle finger of your right hand perpendicular to each other:

Figure 1: The three axes form a right-handed system

Now orient your hand so your thumb points along the X-axis in the positive direction (direction of increasing coordinate numbers), your index finger along the positive Y-axis, and your middle finger along the positive Z-axis. Another way of looking at it is, if you placed your eye at the origin, and you could see the three arrows pointing in the directions of positive X, positive Y and positive Z as in Figure 1, the order X, Y, Z would go clockwise.

Figure 2: Another view of right-handed system

Another way to visualize this is to make a fist with your right hand, with your curled fingers towards you. Stick out your thumb directly to the right (X). Now aim your pointer finger straight up (Y). Finally, make your middle finger point toward yourself (Z). This is the view from directly above the origin.

## Axes Of Rotation

Consider a spinning sphere. Every point on it is moving, except the ones along the axis. These form a motionless line around which the rest of the sphere spins. This line is called the axis of rotation.

More precisely, the axis of rotation is a point or a line connecting points that do not change position while that object rotates, drawn when the observer assumes he/she does not change position relative to that object over time.

Conventionally, the direction of the axis of rotation is such that if you look in that direction, the rotation appears clockwise, as illustrated below, where the yellow arrow shows the rotational movement, while the purple one shows the rotation axis:

To remember this convention, hold your right hand in a thumbs-up gesture: If the rotation follows the direction of your curled fingers, then the direction of the axis of rotation is considered to be the same as the direction which the thumb is pointing in.

This gesture is a different form of the right-hand rule and is sometimes called the right-hand grip rule, the corkscrew-rule or the right-hand thumb rule. From now on we will refer to it as 'the right-hand grip rule'.

When describing the direction of a rotating object, do not say that it rotates left-to-right/clockwise, or right-to-left/counterclockwise. Each of these on their own are meaningless, because they're relative to the observer. Instead of saying this, find the direction of the axis of rotation and draw an arrow to represent it. Those who know the right-hand grip rule will be able to figure out what the direction of rotation of the object is, by using the rule when interpreting your drawing.

# Coordinate Transformations

## Coordinate Transformations

A transformation is any operation that changes coordinate values in some way. For example, if you pick up an object and move it to a different place in the room without changing its orientation, then the coordinates of each point on the object relative to the room are adjusted by an amount that depends on the distance and direction between the old and new positions. This is called a translation transformation.

 Object at original location Object translated to new position

Simply turning the object without moving it from its original location is called rotation.

Object rotated 45°

If the object were to get bigger or smaller, that is a scaling transformation. In the real world, only a few objects can be scaled in this way. For example, a balloon can be inflated or deflated to a larger or smaller size, but a bowling ball cannot. Regardless of what can and can't be re-sized in the real world, any object can be scaled (re-sized) in the world of computer graphics. Scaling may be uniform, i.e. apply equally in all dimensions, or non-uniform.

 Object uniformly scaled to 50% of original size Object scaled vertically to 50% of original size

## Linear Transformations

The main types of coordinate transformations we’re concerned with are called linear transformations. Lines that were straight before the transformation remain straight. i.e. they do not become curved. For example, the following diagram illustrates three linear transformations applied to the square in the center: Clockwise from the left, a shear or skew, a scale, and a rotation, plus one non-linear transformation that causes two sides of the box to become curved.

## Multiple Transformations

It is possible to concatenate or compose a series of transformations. The resulting transformation can do many things in one operation — translation, rotation, scaling etc. However, the order of composition of the component transformations becomes important. In general, transformations are not commutative. For example, compare the result of moving our model some distance along the Y axis followed by rotating it about the X axis (If this doesn't make sense, consider that the axes are fixed, they aren't moving with the object. More on that later Global and local coordinates):

Translation followed by rotation

versus the result of doing the rotation first:

Rotation followed by translation

In some instances, the three forms of transformation may be applied on a single object concurrently. Such a feature exists in Blender and is normally implemented in creating animations. For example, you can decide to pick up the object (first transformation - translation), twist it (second transformation - rotation), and, in a 3D modeling environment, increase the size of the object (third transformation - scaling).

## Inverse Transformations

Often there is a need to find the inverse of a transformation. That is, a transformation that has the opposite effect. For example, a rotation of +45° about the X axis is undone by a rotation of -45° around the same axis.

Inverses have many uses, one of which is to simplify the construction of certain kinds of transformations.

For example, it is easy to construct a rotation transformation about the X, Y or Z-axis of the coordinate system. But what about a rotation of Θ° around an arbitrary axis? This can be made out of the following parts:

• a translation that makes the rotation axis pass through the origin.
• rotations about the Y and/or Z axes, as appropriate, so the rotation axis lies along the X axis.
• a rotation of Θ° about the X axis.
• the inverse of the rotations that aligned the rotation axis with the X axis.
• the inverse of the translation that made the rotation axis pass through the origin.

Most of the transformations we deal with in 3D modelling have an inverse, but not all. See the next section for some that don’t.

## Projections

Most of our display and output devices are not three-dimensional. Thus, three-dimensional images need to be projected onto a two-dimensional surface (like a display screen or a printed page) before we can see them.

There are two main ways to perform such projections. One is orthographic projection, where parallel lines are drawn from all points of the three-dimensional object until they intersect a plane representing the display surface:

More on orthographic projections

The other way is perspective projection, where the lines drawn are not parallel, but intersect at a point representing the location of the eye of the viewer:

Projections are also linear transformations. But since they take a three-dimensional space and flatten it onto a two-dimensional surface, some information is lost. Those transformations are non-invertible i.e. they cannot be undone, at least in a unique way as the depth information is gone.

More on perspective projections

The mathematics of perspective were first worked out in the 11th century by Alhazen, and used to great effect by the Italian Renaissance painters four hundred years later.

--

# Orthographic Views

Blender provides two different ways of viewing 3D scenes:

• orthographic view

and

• perspective view.

In order to use them effectively, you need to understand their properties.

An orthographic view (or projection) of a 3D scene is a 2D picture of it in which parallel lines appear parallel, and all edges perpendicular to the view direction appear in proportion, at exactly the same scale.

Orthographic views are usually aligned with the scene's primary axes. Edges parallel to the view axis disappear. Those parallel to the other primary axes appear horizontal or vertical. The commonly used orthographic views are front, side, and top views, though back and bottom views are possible.

Uniform scale makes an orthographic view very useful when constructing 3D objects, not only in computer graphics, but also in manufacturing and architecture.

Here's one way to think about the orthographic view:

Imagine photographing a small 3D object through a telescope from a very great distance. There would be no foreshortening. All features would be at the same scale, regardless of whether they were on the near side of the object or its far side. Given two (or preferably three) such views, along different axes, you could get an accurate idea of the shape of the object, useful for "getting the feel" of objects in a virtual 3D world where you're unable to touch or handle anything!

## Example

Here is a drawing of a staircase:

An isometric view of a staircase

and here are three orthographic views of the same staircase, each outlined in red:

Figure 1: Orthographic views of a staircase

The views are from the front, top, and left. Dashed lines represent edges that, in real life, would be hidden behind something, such as the left wall of the staircase. (Think of each view as an X-ray image.)

The leading edges of the steps are visible in both the front and top views. Note that they appear parallel and of equal length in 2D, just as they are in 3D reality.

# Perspective Views

As you know, the main reason for modeling 3D objects in Blender is to render images that exhibit the illusion of depth.

Orthographic views are great for building a house, but seriously flawed when it comes to creating realistic images of the house for use in a sales brochure. While a builder wants blueprints that are clear and accurate, a seller wants imagery that's aesthetically pleasing, with the illusion of depth. Blender makes it easy to use tricks like perspective, surface hiding, shading, and animation to achieve this illusion.

How does perspective work?

The essence of perspective is to represent parallel edges (in a 3D scene) by edges (in the 2D image) that are not parallel. When done correctly, this produces foreshortening (nearby objects are depicted larger than distant ones) and contributes to the illusion of depth.

Perspective is challenging to draw by hand, but Blender does it for you, provided you give it a 3D model of the scene and tell it where to view the scene from.

If you're confident you understand perspective, you can skip the rest of this module and proceed to the "Coordinate Spaces in Blender" module.

 Blender only does 3-point perspective, not 1-point or 2-point.

## One-point Perspective

Figure 1: 1-Point Perspective.

Drawing classes teach various kinds of perspective drawing: one-point perspective, two-point perspective, and three-point perspective. In this context, the word "point" refers to what artists call the vanishing point.

When you're looking at a 3D object head-on and it's centered in your view, that is an example of one-point perspective.

Imagine looking down a straight and level set of train tracks. The tracks appear to converge at a point on the horizon. This is the vanishing point.

The image on the right is a 2D image of a cubic lattice or framework. Like any cube, it has six square faces and twelve straight edges. In the 3D world, four of the edges are parallel to our line-of-sight. They connect the four corners of the nearest square to the corresponding corners of the farthest one. Each of these edges is parallel to the other three.

In the 2D image, those same four edges appear to converge toward a vanishing point, contributing to the illusion of depth. Since this is one-point perspective, there is a single point of convergence at the center of the image.

## Two-point Perspective

Figure 2: 2-Point Perspective.

Now the cube is at eye level, and you're near one of its edges. Since you're not viewing it face-on, you can't draw it realistically using one-point perspective. The horizontal edges on your left appear to converge at a point on the horizon to the left of the cube, while those on the right converge to the right. To illustrate the cube with a good illusion of depth, you need two vanishing points.

## Three-point Perspective

3-Point Perspective.

Now imagine you're above the cube near one of its corners. To draw it, you'd need three vanishing points, one for each set of parallel edges.

From that perspective, there are no longer any edges which appear parallel. The four vertical edges, the four left-right edges, and the four in-out edges each converge toward a different vanishing point.

# Coordinate Spaces in Blender

Figure 1: Objects in a three dimensional space. In the center of the coordinate system is the origin of the global coordinate system.

We'll start looking at how 3D scenes are represented in Blender.

As was explained in the "3D Geometry" module, Blender represents locations in a scene by their coordinates. The coordinates of a location consist of three numbers that define its distance and direction from a fixed origin. More precisely:

• The first (or x-) coordinate of the location is defined as its distance from the YZ plane (the one containing both the Y and Z axes). Locations on the +X side of this plane are assigned positive x-coordinates, and those on the -X side are given negative ones.
• Its second (or y-) coordinate is its distance from the XZ plane, with locations on the -Y side of this plane having negative y-coordinates.
• Its third (or z-) coordinate is its distance from the XY plane, with locations on the -Z side of this plane having negative z-coordinates.

Thus the origin (which lies at the junction of all three axes and all three planes) has the coordinates (0, 0, 0).

## Global and local coordinates

Blender refers to the coordinate system described above as the global coordinate system, though it's not truly global as each scene has its own global coordinate system. Each global coordinate system has a fixed origin and a fixed orientation, but we can view it from different angles by moving a virtual camera through the scene and/or rotating the camera.

Global coordinates are adequate for scenes containing a single fixed object and scenes in which each object is merely a single point in the scene. When dealing with objects that move around (or multiple objects with sizes and shapes), it's helpful to define a local coordinate system for each object, i.e. a coordinate system that can move with, and follow the object. The origin of an object's local coordinate system is often called the center of the object although it needn't coincide with the geometrical center of the object.

3D objects in Blender are largely described using vertices (points in the object, singular form: vertex). The global coordinates of a vertex depend on:

• the (x, y, z) coordinates of the vertex in the object's local coordinate system
• the location of the object's center
• any rotation (turning) of the local coordinates system relative to the global coordinate system, and
• any scaling (magnification or reduction) of the local coordinate system relative to the global coordinate system.

For example, the teacup in Figure 1 is described by a mesh model containing 171 vertices, each having a different set of local (x, y, z) coordinates relative to the cup's center. If you translate the cup (move it without rotating it), the only bits of the model that have to change are the global coordinates of the center. The local coordinates of all its vertices would remain the same.

### Coordinates of child objects

Figure 1b: A parent serves as the source of the global coordinates for its child object. The child is the cup; the parent's orientation is shown with the colored arrows.
Animation of the above

Any object can act as a parent for one or more other objects in the same scene, which are then referred to as its children. (An object cannot have more than one direct parent, but parent objects may themselves be the children of other objects.)

If an object has a parent, its position, rotation, and scaling are measured in the parent's local coordinate system, almost as if it were a vertex of the parent. i.e. the position of the child's center is measured from the parent's center instead of the origin of the global coordinate system. So if you move a parent object, its children move too, even though the children's coordinates have not changed. The orientation and scaling of a child's local coordinate system are likewise measured relative to those of its parent. If you rotate the parent, the child will rotate (and perhaps revolve) around the same axis.

Parent-child relationships between objects make it simpler to perform (and animate) rotations, scaling and moving in arbitrary directions. In Fig. 1b the teacup is a child object of the coordinate cross on the right. That cross is itself the child of an invisible parent. (It is both a parent and child.) In the cup's local coordinate system, it is not rotating, but as the cross on the right rotates around its Z axis, it causes the cup to rotate and revolve. In real animations, it will be much easier when the character holding the cup rotates, the cup changes its position respectively.

## View coordinates

Figure 2: View coordinates and Projection Plane

Taking the viewer of the scene into consideration, there is another coordinate space: the view coordinates. In Fig. 2 the viewer is symbolized by the camera. The Z axis of the view coordinates always points directly to the viewer in orthographic projection. The X axis points to the right, the Y axis points upwards (Fig. 3).

Figure 3: View coordinates in viewing direction

In fact you always work in view coordinates if you don't set it any other way*. This is particularly useful if you have aligned your view prior to modeling something, e.g. if an object has a slanted roof and you want to create a window to fit in that roof, it would be very complicated to build the window aligned to the local coordinate system of the object, but if you first align your view to the slanted roof, you can easily work in that view coordinate system.

(* In the Blender 2.6 series, the default has been changed to global coordinates. View coordinates remain as an option.)

If you work in one of the three standard views (Front/Top/Side) the alignment of the view coordinates fits the global coordinates. Therefore, it is quite natural to model in one of the standard views and many people find this the best way to model.

## Normal coordinates

Figure 4: Normal coordinate spaces for faces. The normal is shown in blue.

Although Blender is a 3D program, only an objects' faces are visible. The orientation of the faces is important for many reasons. For example, in our daily lives it seems quite obvious that a book lies flat on a table. This requires the surface of the table and that of the book to be parallel to each other. If we put a book on a table in a 3D program, there is no mechanism that forces these surfaces to be parallel. The artist needs to ensure that.

The orientation of a face can be described with the help of the so-called surface normal. It is always perpendicular to the surface. If several faces are selected, the resulting normal is averaged from the normals of every single face. In Fig. 4 the normal coordinates of the visible faces are drawn.

This concept can be applied to individual points on the object, even if the points themselves have no orientation. The normal of a point is the average of normals of the adjacent faces.

The images for this tutorial were produced with Blender v2.46.

## UV Coordinates

In later parts (for example, talking about textures) you will come across coordinates labelled “U” and “V”. These are simply different letters chosen to avoid confusion over “X”, “Y” and “Z”. For example, a raster image is normally laid out on a flat, two-dimensional plane. Each point on the image can be identified by X and Y coordinates. But Blender can take this image and wrap it around the surface of a 3D object as a texture. Points on/in the object have X, Y and Z coordinates. So to avoid confusion, the points on the image are identified using U and V to label their coordinates instead of X and Y. We then refer to “UV mapping” as the process of determining where each (U, V) image point ends up on the (X, Y, Z) object.

# Overview

Blender's user interface (the means by which you control the software) is not particularly easy to learn. However, it has improved over time and is expected to continue doing so. The current version of the Blender software is 2.78. You can download it from the Blender Foundation's website.

The tutorials in this section will familiarize you with the basics of the user interface. By the end of this section, you should be able to:

• resize, split, and merge any Blender window;
• change the type of any Blender window;
• access user preferences;
• access panels containing buttons and other controls;
• change the viewpoint of a viewport.

For those new to Blender, this is a fundamental section of the book.

Blender is a complex software package with many customizable features. You can customize the user interface to assign new functions to buttons and hotkeys. In fact, you can change almost anything to suit yourself. However, this complicates the giving and following of directions. It is recommended you adhere to the default screen arrangements of Blender in order to be able to follow the remaining parts of these tutorials. Blender ships with 4 to 5 screen-content arrangements which are suitable for almost any kind of job you'll want to use it for - from creating motion and animation to making games.

We recommend leaving Blender's user interface in its "factory settings" while working through the Noob to Pro tutorials. At the very least, wait until you've mastered the basics before you customize the interface - and we know you definitely will when you master it!

# Keystroke, Button, and Menu Notation

As you read through these tutorials, you will encounter cryptic codes such as  SHIFT + LMB  and Timeline → End Frame. They describe actions you perform using the keyboard and mouse. The notation used in this book comes from the standard used by the Blender community. We will try to import those standards here to facilitate our studies.

If you're reading this book online, you may wish to print this page for future reference. In addition, you can bookmark it in your browser for faster reference.

## Hotkeys

Most computer keyboards have number keys in two different places. A row above the letters, and in a numpad (numeric keypad) to the right of the keyboard. While many applications use these two sets of keys interchangeably, Blender does not. It assigns different functions to each set. If you're using a laptop keyboard without a separate numeric keypad, this might cause some difficulty. You'll need to use your function key to do some things. It is possible to indicate to Blender the type of keyboard you are using, but we strongly recommend you use a standard external keyboard if you use a laptop for these tutorials as it will make your studies and usage of Blender much more straightforward and enjoyable.

This book often assumes your keyboard has a numpad. If yours doesn't, consult the tutorial on Non-standard Input Devices for alternative ways to access the numpad's functions.

### Notation

Notation Action or Key
Alt  (press and hold) the Alt (Option) key
Cmd  (press and hold) the Command or Super key (On a Windows keyboard, the key bearing the Windows logo; on a Macintosh, it bears the word command.)
Ctrl  (press and hold) the Ctrl (Control) key
Fn  (press and hold) the Fn (Function) key (generally found only on laptops)
Shift  (press and hold) the Shift key
Enter  (press) the Enter (Return) key (on the main keypad)
Esc  (press) the Esc (Escape) key
F1  through  F12  function keys F1 through F12 (often in a row along the top of the keyboard)
Space  (press) the space bar (usually unmarked)
Tab  (press) the Tab key
A  through  Z  the letters (on the main keypad)
0key  through  9Key  the numerals (above the letters) on the main keypad
Num0  through  Num9  the numerals on the numpad
NumLock ,  Num/ ,  Num* ,  NUM− ,  Num+ ,  NumEnter , and  Num.  other keys on the numpad
Delete  (press) the Delete key (not  NUM.  !)
Down Arrow  (press) the down Arrow key (not  Num2  !)
Left Arrow  (press) the left Arrow key (not  NUM4  !)
Right Arrow  (press) the right Arrow key (not  NUM6  !)
Up Arrow  (press) the up Arrow key (not  NUM8  !)

Combinations that involve holding down a key while performing another action are written with a plus sign (+). Thus:

•  Shift + Tab  means to  Tab  while holding down  Shift

and

•  Shift + Ctrl + F9  means to  F9  while holding down both  Ctrl  and  Shift .

## Mouse Notation

Blender uses three mouse buttons and the scroll wheel, if you have one. If your mouse only has one or two buttons, consult the tutorial on Non-standard Input Devices for alternative ways to access the functions assigned to these buttons.

Notation Action or Button
LMB  click with the Left Mouse Button
RMB  click with the Right Mouse Button
MMB  press down on (don't turn) the scroll wheel or Middle Mouse Button
SCROLL  turn the scroll wheel in either direction

Mouse and keyboard actions are often combined.  Shift + RMB  means to click  RMB  while holding down  Shift .

You can move through items in a menu by:

• moving the mouse pointer up and down

or

• pressing  Up Arrow  and  Down Arrow

You can enter a sub menu by:

• moving the mouse pointer to the right

or

• pressing  Right Arrow

You can leave a sub menu by:

• moving the mouse pointer to the left

or

• pressing  Left Arrow

To initiate a menu action, you can:

• click  LMB

or

• press  Enter

You can escape from a menu by:

• moving the mouse pointer away from the menu

or

• pressing  Esc

For each menu, Blender remembers your last choice and highlights it for you the next time you enter the menu.

### Notation

Shift + A  Mesh → UV Sphere

Means:

1. Press Shift+A
2. In the menu that pops up, move through the items until Mesh is highlighted
3. Enter the Mesh sub menu
4. Move through the items until UV Sphere is highlighted
5. Press Enter or click the left mouse button to initiate the action

# Non-standard Input Devices

This module is applicable only to users with non-standard input devices. If you have both:

• a three-button mouse

and

• a keyboard with a numpad,

you can skip this module.

Most modern laptops have a pseudo-numpad, a set of keys in the main keypad which double as a numpad. The keys typically used for this purpose are:

 7key 8key 9key 0key U I O P J K L ; M ,Key .Key SLASH

When used as a pseudo-numpad, these keys typically act as the following keys from a true numpad:

 Num7 Num8 Num9 Num/ Num4 Num5 Num6 Num* Num1 Num2 Num3 NUM− Num0 NumENTER Num. Num+

The numpad functions of these keys can often be toggled with  F11  or  NUMLOCK  on PCs or with  F6  on Macs. Alternatively, you can often temporarily activate the numpad behavior by holding down  Fn .

If your keyboard has the alternate labellings but you don't know how they work, consult your laptop owner's manual.

As a last resort, you can use the "Emulate Numpad" feature of Blender. This will allow you to use the normal numeric keys as if they were numpad numerics. Instructions for enabling this feature may be found in the "User Preferences Windows" module.

Blender uses the numeric keypad quite a bit. If you envision using your laptop for this kind of work, it may be worth investing in a USB Numeric Keypad. On eBay, prices for simple external numpads start around \$10 USD.

### Non three-button mouse

For single-button mouse users, make sure that View & Controls (Input for Blender 2.54) (under "User Preferences" on the left-most drop-down menu) → Emulate 3 Button Mouse is enabled.

On many computers with two-button mice,  MMB  can be emulated by simultaneously clicking  LMB  and  RMB . On Windows machines you'll need to enable this in the mouse settings in the Control Panel. On a Mac, open the Keyboard and Mouse preference pane and enable Use two fingers to scroll. Alternatively, by selecting Emulate 3 Button Mouse under User Preferences,  MMB  can be emulated by simultaneously clicking  Alt  and  LMB .

Recent IBM Thinkpad laptops allow you to disable the 'UltraNav' features of the middle mouse button in order to use it as a 'normal' third button. Alternatively, some laptops allow areas (called gestures) on the movement pad to act as  MMB  or  RMB , and these can be set up in the Control Panel in the Mouse Pointer options, selecting gestures and editing features there.

#### Apple single-button mouse

Apple single-button mouse substitutions
Notation Single-button Substitute Description
LMB   MB  the Mouse Button
RMB   Cmd + MB  Apple key + the Mouse Button
MMB   Alt + MB  Option (Alt) key + the Mouse Button

While Mac OS X natively uses both the  Ctrl + MB  and  Cmd + MB  to emulate  RMB , recent Blender releases for Mac OS X use only  Cmd + MB  for this purpose. This behavior is documented in the OSX Tips file that comes with the Mac version. You can also set the mouse to sense a right-click in System Preferences.

Note also that in the new, "unibody" design, the mouse button is under the trackpad, and the shortcut for  RMB  is clicking with two fingers simultaneously, which can be enabled in the System Preferences.

#### Laptops lacking a middle button but with a smart-pad

Many laptops have smart pads. Smart-pads can use gestures to give the effect of  MMB . The default for an Elan® Smart-Pad is two-finger tapping equivalent to clicking a  MMB . Dragging two fingers is the same as turning a mouse wheel.

### Tablet PCs

To get the effect of  MMB  in a viewport, drag your pen around while holding down the  Alt  key.

# Operating System-specific Issues

This tutorial covers user-interface issues that are specific to particular operating systems or window managers. Read the section that applies to your computer; you may skip the rest.

## GNU/Linux

Alt + LMB  is used for changing the angular view on two angular axes of the 3D View window, if  Alt + LMB  moves the current window, then there's a conflict with your window manager. You can resolve the conflict or use  Ctrl + Alt + LMB  or  MMB  instead. (Also, you may have activated Compiz->Rotate Cube. Default configuration for rotating the Cube is also  Ctrl + Alt + LMB ; you may have to change this binding to an alternative configuration.) If you are running KDE this can be resolved by:  RMB  on the title bar of the main Blender window → select Configure Window Behavior → go to Actions → Window Actions → in the Inner Window, Titlebar and Frame section → select the Modifier key to be  Alt  and set all the select boxes beneath it to Nothing. An alternate method within KDE might be to  RMB  click on the title bar of the main Blender window; then select AdvancedSpecial Application Settings...Workarounds and then click Block global shortcuts with Force selected and checked.

In Gnome, Click System → Preferences → Window Preferences. Look for the last three options Control, Alt and Super. Select Super. Now you can press and hold  Cmd  to drag windows around, and use  Ctrl  and  Alt  as normal.

### KDE

Under KDE,  Ctrl + F1  through  Ctrl + F4  are by default configured to switch to the corresponding one of the first four desktops, while  CTRL + F12  brings up Plasma settings. You can change these in System Settings.

### Gnome

You'll want to disable the Find Pointer functionality in Gnome, which will impair your ability to use certain functions such as Snap to grid and the lasso tool. If your mouse pointer is being highlighted when you press and release  Ctrl , go to: Mouse in Gnome's Desktop Settings and uncheck the box Find Pointer.

### Ubuntu

As of Ubuntu versions prior to about 09.10 (“Karmic Koala”), there was a known incompatibility between Blender and the Compiz Fusion accelerated (OpenGL) window manager used in Ubuntu. By default, Compiz Fusion is enabled in Ubuntu, causing the problems to manifest themselves in Blender as flickering windows, completely disappearing windows, inconsistent window refreshes, and/or an inability to start Blender in windowed mode.

The fix for this is simple. Install compiz-switch (might be in universe). Go to Applications → Accessories → Compiz-Switch. This will disable compiz temporarily. Do the same to turn compiz back on when you're done using Blender.

This is no longer needed for current releases of Ubuntu.

## Mac OS X

On Macs with the new thin Apple Keyboard, you may need to press  Fn  in order to use the  F1  through  F12  keys.

To expand a section in Blender, you would usually press  Ctrl + UpArrow . On a Mac, if “Spaces” is enabled, you may have to use  Ctrl + Alt + UpArrow .

NOTE: On Yosemite 10.10.1 with "Spaces" enabled and Blender 2.72b,  Ctrl + UpArrow  doesn't seem to work.

## Microsoft Windows

### Two Ways to Launch Blender

Blender requires a console for displaying error messages, so if you launch Blender by means of an icon, two windows will appear: the graphical user interface plus a console window. Closing either window will terminate Blender. These windows are indistinguishable in the Windows taskbar in versions of Windows before Windows 7, which leads to confusion. Also, launching this way does not provide any way to pass command-line arguments to Blender.

Launching Blender from a command prompt is extra work, but it overcomes these issues:

1. Start → Run...
2. enter cmd
3. enter cd c:\Program Files\Blender Foundation\Blender
4. enter blender

EDIT: Blender version 2.6 onwards doesn't have this problem, and hides the console window by default. You can show it by clicking Window > Toggle system console

### Sticky Keys

Pressing  Shift  five times in a row may activate StickyKeys, an accessibility option which alters how the computer recognizes commands. If a StickyKeys dialog box appears, you should  LMB  the "Cancel" button.

If you don't need the accessibility features, you can disable sticky keys:

1. Start → Control Panel
2. double-click on Accessibility Options
3.  LMB  the Keyboard tab
4. for each of the options StickyKeys, FilterKeys, and ToggleKeys:
1. clear the Use … checkbox
2.  LMB  the Settings button
3. uncheck the Use Shortcut checkbox in the settings
4.  LMB  the OK button for the settings
5.  LMB  the OK button for Accessibility Options

### Multiple Keyboard Layouts

On systems with multiple keyboard layouts, pressing  Shift + Alt  can alter the layout. (For instance, it might change from QWERTY to AZERTY or vice versa.) Because of this issue, Noob to Pro avoids  Shift + Alt  hotkeys.

If you find your keyboard layout altered, press  Shift + Alt  again to change it back.

You can also disable the hotkey:

1. Start → Control Panel
2. double-click on Regional and Language Options
3.  LMB  the Languages tab
4.  LMB  the Details button
5.  LMB  the Key Settings button
6.  LMB  the Change Key Sequence button
7. uncheck the Switch Keyboard Layout checkbox
8.  LMB  the OK button

# Blender User Interface

Here's a preview screenshot of Blender's interface.

For those familiar with older (pre-2.5x) versions of Blender, this will look very different. The redesign makes it much easier to find things.

For a detailed rationale explaining the redesign, read this.

## Why Doesn’t It Follow UI Conventions For [Insert OS Of Choice Here]?

Blender follows its own user interface conventions. Instead of making use of multiple windows as defined by your particular OS/GUI, it creates its own “windows” within a single OS/GUI window, which is best sized to fill your screen. Many people accustomed to how applications normally work on their platform of choice, get annoyed by Blender’s insistence on being different. However, there is a good reason for it.

The essence of the Blender UI can be summed up in one word: workflow. Blender was originally created by a 3D graphics shop for their own in-house use. Being a key revenue engine for them, they designed it for maximum productivity, speed and smoothness of operation. That means avoiding “bumps” that slow down the user. For example, windows never overlap, so there’s no need to keep reordering them. You don’t have to click in a window to make it active, just move the mouse. There is a minimum of interruption from popups asking for more information before performing some action. Instead, the action is immediately performed with default settings, which you can adjust afterwards and get immediate feedback on the results.

Blender may not be “intuitive” to start learning, in that you cannot simply sit down in front of it and figure out things on your own, especially from a position of knowing nothing at all. But once you have picked up some basic conventions, you will find it starts to make sense and then you will be free to experiment and discover things on your own.

## Why Doesn’t It Prompt To Save Changes?

Most modern applications will ask for confirmation if you try to close a document that has unsaved changes. Blender is frequently criticized for not doing so.

But think about it. What constitutes an “unsaved change”? Are switching tools or adjusting the window layout changes worth saving? In Blender’s case, the answer is “yes”, because all that is part of the document state to be restored upon opening. So Blender would have to prompt for confirmation practically every time you closed a document or quit Blender.

Instead, Blender always saves changes when it closes, to a file called 'quit.blend'. The next time you use Blender, simply select File --> Recover Last Session and you can resume right where you left off.

# Blender Windowing System

The Blender user interface may appear daunting at first, but don't despair. This book explores the interface one step at a time.

In this module, you'll learn about Blender windows:

• recognizing windows and their headers,
• the different types of windows,
• how to activate and resize windows,
• how to split and join windows.

You'll also practice launching and leaving Blender.

## An Interface Divided

Blender's user interface is divided into rectangular areas called windows (or sometimes, areas). The overall arrangement of windows is called a workspace.

If you haven't already launched Blender, go ahead and do so. You should soon see something that resembles the following.

Blender has had some major changes to its user interface (UI) since version 2.4x. Some of these changes include moving buttons and changing the space bar hot key from the “add menu” to the “search menu” ( SHIFT + A  is now the "add menu” hot key). This is important to know when trying to follow tutorials.

Other changes include the addition of the tool bar and window splitting widget. The shelf widget (indicated by a plus sign) opens hidden tool shelves. The object tool shelf can be toggled on and off by pressing  T . The properties tool shelf can be toggled on and off by pressing the  N . The split window widget allows you to split and join windows. Blender 2.69 is shown below.

If you see something substantially different...
• You may be running a different version of Blender - perhaps a newer version. The screenshot was made using the 2.69 release.
• The user-interface settings on your computer may have been changed.
Try resetting the user interface with File → Load Factory Settings.
To take a screenshot in Blender, press  Alt + F3 , and click Make Screencast. This will record what's on your screen until you click the red Close button on the info header. The screencasts will be saved in the tmp folder. In Microsoft Windows, the tmp folder is located at 'C:\tmp'.

Did you find all five headers?

Every Blender window has a header. A header can appear at the top of the window, at the bottom of the window, or it can be hidden. Let's take a closer look at the headers.

The header of the Info window is outlined in green.

The header of the 3D View window is outlined in red. Note that it runs along the bottom of the 3D View window, not the top.

The header of the Properties window is outlined in blue.

The header of the Outliner window is outlined in white.

The header of the Timeline window is the one on the bottom (not outlined)

If you click with  RMB  on the header, a menu pops up which lets you move the header (to the top if it’s at the bottom, or vice versa), or maximize the window to fill the entire workspace:

To hide the header completely, move the mouse to the edge of the header furthest from the edge of the window (i.e. the top edge of the header if it is at the bottom of the window, or vice versa); it will change into a vertical double-headed arrow. Now click with  LMB  and drag towards the window edge, and the header will disappear. In its place, you will see the following symbol appear at the corner of the window: . Click this with  LMB  to bring the header back.

## Window Types

Blender has many types of windows (there are 16 of them in Blender 2.69) and a Console for the Python programming language. You've just encountered the Info, 3D View, Properties, and Outliner windows. The rest will be introduced as needed in later modules.

Every window header in Blender has an icon at the left end to indicate the window type. For instance:

• = Info
• = User Preferences
• = 3D View
• = Outliner
• = Properties

If you  LMB  on the icon, a menu will pop up. (If you don't know what  LMB  means, please review the Keystrokes, Buttons, and Menus Notation module.)

By matching the icon in the header to the icons in the menu, you can tell that the window here is a 3D View window.

The menu can be used to alter a window's type. In this screenshot, the user is about to change the window into a Properties window.
 Any window can be changed to any type. Blender doesn't mind if there are multiple windows of the same type.

 The workspace layout is saved along with the document. Anybody subsequently opening the document will see the last-saved layout.

If you've changed any window's type, please change it back (or reload the factory settings with File → Load Factory Settings) before continuing with this tutorial.

## The Active Window

The active window is the one that will respond if you press a key. Only one Blender window is active at any given time.

The active window is usually the one containing the mouse pointer. (Blender uses a "focus follows mouse" user interface model. When a hotkey fails to work as expected, it is often because the mouse pointer has strayed into a neighboring window.) To change the active window, simply move the mouse pointer into the window you wish to activate.

Practice changing the active window by moving your mouse between the 3D View and the Timeline windows. The Timeline window is directly below the 3D View header. At this point, it's worth mentioning that the header for the 3D View window and Timeline window is at the BOTTOM of its own window instead of the top as the name "header" implies.

 When a window becomes active, its header gets brighter.

## Resizing Windows

Resizing windows is easy.

### Dragging on a Border

Step 1
Move the mouse pointer to the border between two windows (the area outlined in red below. The pointer will change to an up/down arrow.
Steps 2-4
Press and hold  LMB .
Drag with the mouse to move the border up and down.
When the border is where you want it, release  LMB .

Whenever you increase the size of one window, you decrease the size of another. That's because Blender has a non-overlapping window interface: unlike many other programs, it does not permit windows to overlap.

### Maximizing a Window

Another way to resize a window is to maximize it. When Blender maximizes a window, it makes the window as large as possible. The previous window configuration is saved.

• To maximize the active window, press  Ctrl + UpArrow  ,  Ctrl + DownArrow  or  Shift + Space .
• When a window is maximized, use  Ctrl + UpArrow  ,  Ctrl + DownArrow  or  Shift + Space  to restore the previous (unmaximized) window configuration.

Practice maximizing and un-maximizing the 3D View and Timeline windows.

 If you are running a version of Blender before 2.57, you cannot maximize a User Preferences window.

## Shelves

You will notice that the 3D View window (the largest window in the screenshots above) has several buttons down the left side. This rectangular portion is called the Tool Shelf. This is like a window within a window - you can drag the boundary between it and the main part of the 3D View to resize.

If you drag all the way to the window boundary, the shelf will disappear. In its place, the following symbol will appear: . Click it to bring the shelf back.

## Too Much To Fit

If a window or shelf contains too much information to fit within its display area, scrollbars will appear along the bottom or right edge. You can scroll the contents by dragging these with  LMB ; alternatively you can drag with  MMB  directly within the contents.

A window header may also contain more than fits within its displayable area. There is no explicit visual clue for this (though some of the widgets at the right edge might not be visible), but if that happens, you can drag sideways within the header with  MMB  to scroll its contents.

## Splitting And Joining Windows

At the top right and bottom left of every window, you will see something like this: . If you move the mouse over the icon, you will see the pointer turn into a cross. At that point, you can do one of the following by clicking and dragging with  LMB :

• Split the window into two copies horizontally by dragging horizontally away from the edge.
• Split the window into two copies vertically by dragging vertically away from the edge.
• Join the window to the adjacent one horizontally (getting rid of it and taking over its space) by dragging towards it.
• Join the window to the adjacent one vertically (getting rid of it and taking over its space) by dragging towards it.

Of course, the last two are only possible if there is in fact another window in that direction. Note: you can only join windows horizontally that are the same height, and windows vertically that are the same width.

## The Default Workspace

If you look at the above screenshot of the default workspace, you will see the following window types:

• The menu bar at the top (outlined in green) is actually a window, called Info . In previous versions of Blender, you could resize this to reveal the User Preferences, but in 2.5x they have been moved to their own window type. Instead, all you can see here if you enlarge the window are some debug messages, which may be removed in a future version of Blender. As of 2.70, the debug messages are still present in this menu.
• The largest window on the screen is the 3D View . This is where you work on your model.
• The Properties window is the tall area on the right; this is where most of the functions are located for performing operations on models, materials etc. In previous versions of Blender this was called the Buttons window. Over time, it evolved into a disorganized area that made it difficult to find things. It has been cleaned up significantly in 2.5x. Note that it defaults to a vertical layout, rather than the horizontal one of previous versions. The new design prefers a vertical layout, which better suits today’s widescreen monitors.
• The Outliner (at the top right) gives you an overview of the objects in your document. As your models get more complex, you will start to appreciate the ability to quickly find things here.
• The Timeline (across the bottom) becomes important when you’re doing animation.

The default layout may not be optimal. For example, if you’re doing a static model or scene, not an animation, you can get rid of the Timeline. If you’re doing heavy script development, you’ll probably want the Console available to try things out. And so on.

## Workspace Presets

In the Info window/titlebar, you will see a menu with an icon like this . Clicking on it with  LMB  will show the following menu:

Selecting from this menu lets you quickly switch between various predefined workspace layouts, tailored to various workflows. Try it and see. You can return to the default layout by selecting “Default” (but note that any changes you make to the layout are immediately associated with the name being displayed here). The menu has a search box at the bottom. Typing text here will restrict the menu to showing items containing only that text. It might not appear to have much use, but in a complicated project that needs dozens of different layouts, the search function could become very useful indeed!

The name of the currently selected item appears to the right of the menu icon. In the illustration above, this is "Default". Blender allows you to rename the current menu item by clicking on it with the  LMB  and typing a new name, so take care not to do so unless you actually want to rename the menu item. For example, if you replace the name "Default" with "MyDefaults", you will subsequently see that "MyDefaults" appears in the list of menu items.

Note also the “+” and “X” icons to the right of the menu; clicking “+” creates a new entry which is a duplicate of the last-selected entry, while clicking “X” gets rid of the currently-selected entry. You will see these conventions appear consistently in menus elsewhere in Blender’s new, revamped interface.

## One Document At A Time

Blender can only work with one open document at a time. To save changes to the current document, select one of the Save options from the File menu (or press  Ctrl + S  to save under the last-saved name). To open a new document (actually load a copy of your last-saved user preferences), select “New” from the File menu (or press  Ctrl + N ), and select “Reload Start-Up File” from the popup that appears, but be aware this will not automatically save any changes to the previous document.

## Scenes

A scene is like a separate Blender-document within-a-document. Different scenes within the same document can easily share objects, materials etc. You can define them once and make different renderings and animations from them. You create, delete and switch scenes using the scene menu in the info header. A new document starts by default with just one scene, called “Scene”.

## Leaving Blender

To exit Blender:

1. If there's a tool active, press  Esc  to exit the tool.
2. Press  Ctrl + Q . This brings up an OK? menu.
3. Confirm Quit Blender by clicking  LMB  or pressing  Enter .
 Blender will not prompt you to save your work. However, you can easily pick up where you left off by using File → Recover Last Session.

# User Preferences Windows

In this module, we'll take a closer look at the User Preferences window. In the process, you'll encounter three different user-interface controls: radio buttons, toggle buttons, and sliders.

## Saving User Preferences

Most applications have a place to keep user-configured settings (including document defaults), separate from any user-created documents. Blender works in a slightly different fashion. All user-configured settings are saved in every document you create. Each time you create a new Blender document, it reloads your default document, which is called .B.blend. To save your current state as the default document, press  CTRL + U . This will save everything you’ve done to the current in-memory document, including objects and materials created, to .B.blend.

## Accessing the User Preferences

First we must open the User Preferences window. There are 3 ways to do this:

• Click  LMB  File → User Preferences...
• Change the window type of the top header to User Preferences and drag the header down.
• Press  CTRL + ALT + U , which will open the User Preferences into a separate window which you can resize at will.

The User Preferences window should look something like the screenshot below.

In order to get to modeling and rendering sooner, this tutorial will cover only a few of the many user-settable preferences.

### Auto Save

As the name suggests, Auto Save automatically saves the current .blend after a specified period of time. The settings are:

• Auto Save Temporary Files: This enables/disables the auto save feature.
• Timer (mins) slider: This specifies the time in minutes between each auto save.
 In Blender 2.66 and later, an additional option is available: "Keep Session". This option always saves a quit.blend at Quit, and loads it on starting Blender. If you close Blender with an "empty file" session (the startup.blend), it keeps the Window header name "Blender" and treats the session as if no file was loaded. For the purposes of this tutorial, it can be left disabled.

### Number of Undo Levels

Next we'll look at the undo settings. By default, Blender remembers your last 32 actions and allows you to undo them one at a time by pressing  Ctrl + Z . If your computer has plenty of memory, you may wish to increase that number. If it has relatively little memory, you might consider decreasing it to 10 or 20. The Memory Limit slider specifies the amount of RAM (in megabytes) to use for storing the undo levels. Undo level "0" is unlimited.

Blender uses numberpad keys (such as  7 ) to control the 3D View and ordinary numeral keys (such as  7 ) to change layers. If you are working on a laptop or if you find the numberpad inconvenient, you can select Emulate Numpad to reassign the 3D View controls to the ordinary numeral keys.

If you ever need to restore Blender to its factory settings, you can delete your personal ".blend" file then restart Blender, or click  LMB  File → Load Factory Settings

 The second method only affects the current session. To make the settings persist, you would need to save them with  Ctrl + U  or File → Save User Settings - This menu name has been changed to Save Startup File in Blender 2.67b.

# Properties Window

The Properties window is where you will find most of the functions that Blender can perform with objects and materials, animation, rendering, etc. It is the area where you will see the greatest number of changes from earlier versions of Blender (in which, it was called the Buttons window). Hopefully you’ll agree the new layout makes it much easier and quicker to find things!

In the header of the Properties window, you will see a row of buttons that looks like this: The actual icons will vary depending on the type of object selected in the 3D view. In the default layout, the Properties window may be too narrow to show the entire row, in which case you can widen the window, click drag across the buttons with  MMB  to scroll the button row, or use your mouse wheel within them. Each of these buttons gives you access to a different context, or subsection of the Properties settings. Unlike older verions of Blender, there are no more “subcontexts” — no additional buttons will appear in the header when you click any of these.

# The Contexts

## Render Context

Here we find the settings that control overall rendering of the final images, i.e. what resolution to use, output format, performance, post processing, etc.

## Render Layers Context

Additional settings that offer finer control over rendering of the final images: which scene layers to render, which separate parts (passes) of the rendering process to actually perform, and how to group them into render layers (not to be confused with the scene layers) for input into subsequent compositing.

 In versions of Blender prior to 2.67, these settings were combined into the Render Context.

## Scene Context

Contains settings for colour management, choosing which camera to use for rendering, and units and gravity settings for physical modeling.

You can also select another scene to be a “background” for this scene. That is, all renders of this (foreground) scene will also include the contents of the background scene, as though they had been copied into this scene. While the background appears in the 3D viewport when editing this scene, none of its contents are editable, or even selectable; that has to be done in the background scene itself.

## World Context

Settings that govern the environment in which the model is rendered. e.g. background sky color, mist and star settings, lighting etc.

## Object Context

Settings that apply to all types of objects. e.g. overall transformations, layer assignments, grouping etc. The settings shown here (and any changes made) apply to the last object selected. This is also the case for the following object-specific contexts.

## Object Constraints Context

These settings limit the motion of the object for animation purposes. The limits can also be tied to the motion of other objects in various ways.

## Object Modifiers Context

Settings for applying modifiers to the object geometry. These make changes to the geometry that only take effect at rendering time. Note: lamps, cameras and empty objects cannot have modifiers.

## Object Data Context

Settings specific to the type of object, e.g. mesh vertex groupings, text font, lamp settings, camera settings, etc. This is reflected in the icon, which changes according to the type of object selected.

## Material Context

The material settings for an object control its appearance, e.g. its colour, whether it has a shiny or dull surface, how transparent it is, and so on.

 The chosen rendering engine — Blender Internal (the default), Blender Game, or Cycles — will impact the choices available for material and texture settings.

## Texture Context

The texture settings specify patterns that break up the uniform appearance of a material. These patterns can affect the colour of the material, give it a rough surface, or modify it in other ways.

## Particles Context

An object can be set to emit particles, like smoke, flames or sparks. The concept of “particles” (and the underlying algorithms) also includes the generation of hair or fur. Particles can be entirely custom objects, to produce effects like blades of grass interspersed with flowers in a field, water droplets on a wet surface, or even scatterings of entire buildings to make up a large cityscape!

## Physics Context

Settings that control how the object reacts to forces similar to objects in the real world, e.g. whether it behaves like a rigid body that keeps its shape but can be knocked around, something soft e.g a pillow, or a flowing liquid.

## Where Did The Old Stuff Go?

For those used to older (pre-2.5x) versions of Blender...

The old Logic Context has been moved into its own window type, the Logic Editor.

The old Script Context is gone. Python scripting is now much more closely integrated into the Blender UI, and old scripts will not work anyway.

The functions of the other contexts have been rearranged into the new contexts as listed above. Once you get used to the new arrangement, it should make much more sense than the old one.

# 3D View Windows

3D View windows are used to visualize 3D scenes. You’ll do a lot of work in these windows, so you will need to learn your way around.

 The 3D view only shows an approximation of the final appearance of the scene. The overall geometry should be correct, but don’t expect accurate rendition of materials, textures, lighting etc, since that can be very time consuming. The 3D view is designed to respond to your actions at interactive speeds. There are additional view options (wireframe, hiding etc) that make it easier to see which parts of the model you’re working on, have no effect on the final render. You can change your viewpoint at any time (which will be essential while working on your model/scene), while the viewpoint of the render is controlled by the camera position.

In this module, you'll learn:

• to recognize 10 things commonly seen in viewports
• to tell which mode Blender is in
• how to change viewport options and viewpoints
• how to position the 3D cursor

You'll also learn the fundamentals of:

• visibility layers

## The Viewport and its Contents

Aside from its header, the remainder of a 3D View window is its viewport. You use viewports any time you need an up-to-date view of the scene you're working on.

Viewports are busy places. Go on a scavenger hunt and see what you can find in a simple viewport.

1. Launch Blender.
2. Just so we're all looking at the same scene, load the factory settings using File → Load Factory Settings.
3. Confirm the “Load Factory Settings” popup with  LMB  (or  Enter ).
4. If the NumLock indicator on your keyboard is unlit, press  NumLock  so that numpad hotkeys will work properly.

(If you're unsure what  LMB  means, please review the Keystroke, Button, and Menu Notation module.)

You should see something like this:

Here the viewport has been outlined in red to focus your attention on it.

### A Virtual Scavenger Hunt

Look at the default scene and find the following eight items:

In the Center

1. a solid gray cube with orange edges.

• This is the default cube, your first Blender object!

2. Three arrows, one red, one green and one blue, their tails joined to a white circle

• This is not an object (part of your model/scene), but part of Blender’s user interface for manipulating objects. It is the manipulator, also known as the 3D transform widget.
• The arrows represent the directions of the X, Y and Z axes of the currently chosen transform orientation coordinate system. Initially this is the global coordinate system.
• The circle represents the center of the selected object (the cube).
• If you don't know what the "global coordinate system" is, please review the module on Coordinate Spaces in Blender.
If you don't see the manipulator...
• It's possible that a tool is active. Press  Esc  to cancel any tool action.
• Another possibility is that the manipulator has been disabled:
• Toggle it on or off with  Ctrl + Space .

3. A red-and-white striped circle with black cross-hairs

• This is not an object. It is the 3D Cursor, which indicates where newly-created objects will appear in the scene.
• The cursor is similar to the insertion point in a text editor, which indicates where new text will be inserted in a document.
In the Lower Left Corner

4.

• This is not an object. It is the mini axis, and its orientation matches that of the global coordinate system, with the usual conventions: red for X, green for Y and blue for Z. Think of it as a little compass, reminding you which way is left/right, front/back and up/down.

5. The notation "(1) Cube"

This is not an object. It is object info, indicating that:
• You're viewing the first frame of an animation.
and
• The current or most recently selected object is named "Cube".
In the Upper Left Corner

6. The notation “User Persp”

This is not an object. This tells you which mode the viewport is in. The first word will change if you select one of the perfect views or the camera view (see below), otherwise it just says “User”, and the second word is “Persp” or “Ortho” to indicate whether this is a perspective or orthographic view.
To the Right of Center

7. A black round thing that resembles a sun symbol

This represents a lamp, a light source for the scene. (It is an object.)

8. A pyramidal wireframe item

This represents a camera, a viewpoint that can be used for rendering. (It too, is an object.) The direction it is looking is out the base of the pyramid. The solid triangle attached to one side of the base is to remind you which way is up in the image that the camera takes.
On a small display, the camera might initially lie outside of the viewport and thus be invisible. In that case, zoom out by scrolling with  MMB  until it becomes visible.
Throughout

9. A dark gray background, divided into squares by lighter lines. This is the grid floor, which you can (but don’t have to) use as a ground plane for positioning your models.

Each grid square is one blender unit (or BU) on a side. A BU can be whatever you wish, e.g. an inch, a centimeter, a mile, or a cubit. Blender lets you choose your scene scale in the Scene tab of the Properties Panel.

10. Three mutually perpendicular coloured lines associated with the grid floor: the red and green ones lying horizontally in the floor and the blue one running vertically. These are the global coordinate axes for orienting your scene. Red is the X-axis, green the Y-axis, and blue the Z-axis.

• In Blender 2.67a, you can't see the blue line for Z-axis here, but you can see it in Front or Side view.

## Modes

Blender has many modes, i.e. settings that affect its behavior, and this is especially true of the 3D View window.

Sometimes it's not obvious which mode is active. This leads to mode errors where Blender will do something you didn't expect because you thought it was in one mode and it was actually in another.

The function performed by a hotkey or mouse button can depend on:

• what mode the user interface is in,
• whether the keyboard is in NumLock mode,
• which window is active,
• the mode the active window is in,
• which item or items are selected,
• whether you've initiated a hotkey sequence.

It helps to recognize the common modes and how to get out of them.

### Object Mode vs. Edit Mode

The 3D View windows are normally in Object Mode. In this mode:

• The mouse pointer is a white arrow (on MacOS it is black).
•  RMB  is used to select objects in the scene

If there are objects in the scene, you can get into five other modes:

• Edit Mode: used to edit the shapes of objects
• The mouse pointer is a thin inverse-video cross.
•  RMB  is used to select vertices, faces or edges of the current object.
• Press  Tab  to enter/exit this mode.
• Sculpt Mode
• The mouse pointer is now a thin, orange circle.
• Vertex Paint
• The mouse pointer is the same as in sculpt mode, a thin, orange circle.
• Texture Paint
• The mouse pointer is a thin white circle.
• Weight Paint
• The mouse pointer is again, a thin orange circle

These modes are also indicated by a menu in the 3D View header. You can use this menu to change modes.

These modes are a setting shared by all 3D View windows. In other words, when you change the mode in one window, any other 3D View windows change mode also.

## Viewport Options

 The options in this section only affect 3D View viewports. They do not affect renders.

### Solid vs. Wireframe

By default, the 3D View window draws objects using the Solid drawtype, in which surfaces are opaque. To toggle between Solid and Wireframe drawtype (edges only, no faces) for a particular viewport:

1. Activate the 3D View window.
2. Press  Z .

Alternatively, you can choose these and other drawtypes from the "Viewport shading" menu in the 3D View window header.

### Orthographic vs. Perspective

By default, viewports draw orthographic views. To toggle a viewport between orthographic and perspective views:

1. Activate the 3D View window.
2. Press  Num5 .

(If you're unsure what the difference is, please review the "Orthographic Views" module and the "Perspective Views" module.)

Note this perspective versus orthographic setting for the 3D viewport is completely separate from the similar setting in the camera properties. The former takes effect while you’re working on the model, the latter when you render.

So why have a separate setting for the 3D view? Because certain aspects of modelling are easier in one view than another. If the final render will be using perspective, then showing perspective in the 3D view naturally gives you a better idea of how the final render will look. But perspective foreshortening can sometimes make it hard to ensure the model has the proper shape, which is why there is the option to switch to orthographic view.

If you have trouble distinguishing between orthographic view and perspective view

... you should activate the View Name option. This is enabled by default and causes the name of the current view ("User Persp", for instance) to appear in the upper left corner of every viewport. If there is no text, then you can enable it by:

1. Accessing the User Preferences window.
2. Click on the Interface tab.
3. Enable View Name.

## Changing Your Viewpoint, Part One

Each viewport has a viewpoint, which takes into account:

• the location of the viewer in the 3D scene (There doesn't need to be an object at that location.)
• the direction the viewer is looking
• the magnification (or zoom factor) used

Changing your viewpoint allows you to navigate your way through a 3D scene.

• Zooming
• Orbiting/View Rotation
• Perfect Views.

Additional techniques will be covered later in this module.

### Zooming

Blender offers several ways to zoom in and out:

• Use  SCROLL
• Click and drag vertically with  Ctrl + MMB .
• Use  Num+  and  NUM−  to zoom in and out in small increments.

Note the following limitations of Blender's zoom feature:

• If the viewport is in orthographic mode, Blender zooms as if looking through a telescope. You can increase the magnification, but the viewpoint's location doesn't change. For this reason, you cannot zoom into or through objects in orthographic mode.
• If the viewport is in perspective mode, Blender zooms to the center of the viewport. The viewpoint can pass through objects, but can't pass beyond this point, no matter what you do. Zooming only gets slower and slower and slower. If the center of the viewport is somewhere you don't expect, zooming may appear to be broken.

### Orbiting and View Rotation

Let's fly around in the default cube, viewing it from different angles. In this way you'll see that it really is a cube, centered on the origin, half above the X-Y plane and half below it.

1. Activate the 3D View window by placing the mouse pointer inside it.
2. Now you can:
• Click and drag with  MMB  to orbit freely around the center of the view.
• Use  Shift + Alt + SCROLL  to rotate the viewpoint vertically around the center of the view.
• Use  Num2  and  Num8  to rotate the viewpoint vertically around the center of the view in 15-degree increments.
• Use  Ctrl + Alt + SCROLL  to rotate the viewpoint around the Z axis.
• Use  Num4  and  Num6  to rotate the viewpoint around the Z axis in 15-degree increments.

If this is all very confusing for you, don't worry! You'll learn as you get more experience.

When you are finished flying around the cube, you can restore the original view by reloading the factory settings with File → Load Factory Settings.

If the hotkeys don't work...

You may have pressed number keys above the letters instead of the ones on the numpad. If you do, the default cube will vanish. This is because the scene consists of multiple layers. The default cube is in layer 1, and you've told Blender to switch to the layer of the number you just pressed. The selected object (the cube in this case) remains in layer 1, which is no longer visible. For instance,  2Key  tells Blender to switch to layer 2. To switch to layer 1 again, press  1Key . You can view the different layers by clicking on the little squares on the layer map:

 The center of the viewport is not marked, i.e. it's difficult to tell where it is. This can cause unexpected behavior during rotation. 

### Perfect Views

It's often useful to get a perfect view of a scene, i.e. to view it along one of the main axes, with the other two main axes oriented up-down and left-right.

Perfect View Hotkeys
Hotkey View Axis Pointing Right Axis Pointing Up
Num7  "top" +X +Y
Ctrl + Num7  "bottom" +X -Y
Num1  "front" +X +Z
Ctrl + Num1  "rear" -X +Z
Num3  "right side" +Y +Z
Ctrl + Num3  "left side" -Y +Z

The following screenshot shows all three perfect views plus camera perspective for the Suzanne primitive:

This layout is used so often, it has a keyboard shortcut: ( CTRL + ALT + Q ).

## Positioning the 3D Cursor

Positioning the 3D cursor is a very basic operation, yet one that many beginners find challenging. It touches on an issue common to all 3D graphics software: "How do you specify points in a 3D scene when we can only see two dimensions at a time?"

### Basic Technique

1. Go into either Object Mode or Edit Mode.
2. Move the mouse pointer to the desired position (in any viewport).
3. Click  LMB .

### Two Challenges

Challenge #1. Using only tools presented thus far, try positioning the 3D cursor on the virtual camera.

Try it!

When you're done, check your work by orbiting the camera.

Perhaps you thought you were done when you clicked on the camera. But the moment you changed your viewpoint, you probably found that the 3D cursor was actually behind (or in front of) the camera.

Hints:

• Try positioning the cursor in two different perfect views.
• Use orthographic, not perspective, view.

Challenge #2. Using only tools presented thus far, try repositioning the 3D cursor at the origin (that is, at the center of the cube).

As before, check your work by orbiting the cube. Don't spend too much time on this.

"I found that I would select the cube when left clicking on it in object mode, if the "Use 3d transform manipulator" button was enabled. To toggle this off, you click on the gray pointing hand in the 3d panel header, or (Ctrl Space)."

"When you want the cursor back into the cube, just select the camera with RMB, put the cursor into the cube following the steps above, and re-select the cube with RMB."

"I've discovered it helps a lot if you are in Object Mode and not in Edit Mode. I wrote the following before discovering this: The problem with this exercise, for me, is that left clicking on the cube selects the cube instead of moving the 3d cursor. If I click on the cube outside of its central white circle I can get the cursor to move there, but only to outside of this white circle, and even then this only works sometimes."

"I failed at this until I had zoomed in close enough to the cube. When I was too far zoomed out I kept selecting the cube rather than creating an edit point."

"I had the same problem and found it was because the cube was selected. I made sure I was in object mode, right clicked on the camera to select the camera instead of the cube, and I could then position the edit point in the cube. However, doing this messed up the next part of the tutorial because you cannot switch into edit mode with the camera selected! Perhaps the suggestion of trying to put the 3D cursor in the cube should be dropped as it raises too many questions at this stage."

"You can deselect all by pressing the AKEY or the select button in the 3D View."

"Use wireframe mode works better to get the cursor in."

"To get it back in the cube: 1) Make sure you're in object mode. 2) Select the cube. 3) Object > Snap > Cursor to selection (cursor refers to the 3D cursor here) so it puts it right in the middle of the cube."

"I think it's an essential point to note that in order to place the cursor inside the cube, the cube must NOT be selected. AKEY was probably the best way to deselect the object."

"If I remember correctly, undo history gets cleared when you switch between object and edit mode."

"I wasted a lot of time here. Thank you to the reader who suggested (on the 3D view header) Object > Snap > Cursor to selection. It was the only thing that worked to get the cursor visible again and placed where clicked."

"I missed the point of the exercise first time around. You can't set a 3D point on a 2D screen without technique. Orthographic views are crucial. I am just learning, but take that, at least, away from it."

"Positioning the 3D cursor in othographic views always made it snap to the cube surface, making it impossible to center precisely. Fix this by disabling "Cursor Depth" on the "interface" tab under "User Preferences".

"The phrase check your work by orbiting the camera needs additional clarification, such as a referenced section or the precise commands to use."

### More Ways to Position the Cursor

Here's an easy way to position the cursor at the center of an object:

1. Make sure Blender is in Object Mode, with the object selected.
2. Move the mouse pointer to any 3D View window.
3. Snap the cursor to the selected object using either:
•  Shift + S Cursor to Selected
or
• Object → Snap → Cursor to Selected

Here's 2 easy ways to relocate the cursor to the scene's origin (0, 0, 0):

1. Move the mouse pointer to any 3D View window.
2. Press  Shift + C  to reset the cursor to the origin.
• Note that this also changes the view location, meaning that when you zoom in, you won't zoom in to the scene origin.
3. A better way is to click Object → Snap → Cursor to Center
• You can also do this by  Shift + S Cursor to Center.

## Changing Your Viewpoint, Part Two

Now you'll learn some additional techniques for obtaining the view you want:

• Panning
• Centering
• Jumping to the camera's viewpoint
• Zooming in on a selected area

### Panning

When you orbited the cube, the viewpoint's position and direction both changed at the same time. You also can shift the viewpoint up-down or left-right without changing its direction. (This is similar to the side-scrolling effect in the classic Mario and Sonic video games.)

This is called panning, and it's an important skill to master. Try it now:

1. Activate a 3D View window by placing the mouse pointer inside it.
2. Now you can:
• Use  Shift + SCROLL  to pan up and down.
• Use  Ctrl + Num2  and  Ctrl + Num8  to pan up and down in small increments.
• Use  Ctrl + SCROLL  to pan left and right.
• Use  Ctrl + Num4  and  Ctrl + Num6  to pan left and right in small increments.
• Click and drag with  Shift + MMB  or  Shift + Alt + LMB  to pan freely in the viewplane.

You will likely find this to be a distraction in some cases. To move the viewpoint position back to the center, snap the cursor to the center, then click View → Align View → Center View to Cursor. You could also snap the cursor to the center then press  Ctrl + Num. .

In version 2.74 use  Alt + Home.  to center the view to the cursor.

### Centering

When you zoom or rotate the view, you always zoom or rotate around the center of the view.

To make sure everything in your scene is visible:

1. Press  Home .

To center the view on an arbitrary point:

1. Move the 3D cursor to the point of interest.
2. Verify the cursor position from a second viewpoint.
3. Press  Alt + Home  to center the view.

To center the view on an object in the scene:

1. Make sure Blender is in Object Mode.
2. Zoom out until the object is in the viewport.
3. If any objects are selected, use  A  (or Select → Select/Deselect All) to deselect them.
4. Select the object of interest by clicking  RMB  on it.
5. Press  Num.  to center the view.

### Jumping to the Camera's Viewpoint

To see the scene as the virtual camera sees it, press  Num0 . Afterwards, you can rotate, pan, and zoom normally, but the virtual camera will not follow. To go back to your previous view, press  Num0  again. (In the latest versions of Blender, the virtual camera can be made to follow all the changes made in viewpoint while in camera view by checking the option "Lock Camera to View" on the Transform panel. Hit  N  on your keyboard to bring up the transform panel. To disable this option uncheck "Lock Camera to View.")

### Zooming into a Selected Area

Suppose you want to get an extreme closeup of a particular area. Because there's no center mark on the viewport, you might have to pan and zoom several times to get the desired view.

The shortcut for zooming to an area is:

1. Activate a 3D view window that contains the area of interest.
2. Press  Shift + B . A crosshair appears in the viewport.
3. Click and drag with  LMB  to draw a rectangle around the area of interest.
4. When you release  LMB , the viewport will zoom in on the area you selected.

You can also change your viewpoint in the 3D view by “walking” or “flying” through it. To activate this, press  SHIFT + F . By default in Blender 2.70, this puts you in “walk” mode. Earlier versions only offered “fly” mode. (In Blender 2.70 and later, you can choose which one you prefer in User Preferences, under the Input tab.)

In both modes, helpful prompts appear in the header of the 3D view window to remind you of the key functions while the mode is in effect. When you have reached the position and orientation you want, press  LMB  or  ENTER  or  SPACE  to end the navigation mode and stay there, or  RMB  or  ESC  to abandon the navigation mode and be teleported immediately back to your original position and orientation.

### Walk Mode

In this mode, you move the mouse to turn your view up/down/left/right, and  W ,  A ,  S  and  D  or the corresponding arrow keys to move forward, left, back or right, and  E  and  Q  to move up or down respectively. Hold a movement key down to keep moving. Movement stops as soon as you release it. Pressing  MMB  will “teleport” you close to whatever objects lie within the crosshairs at the centre of the view.

You can also use  TAB  to turn on gravity. Make sure there is a floor or other object under you to land on! With gravity on, you can no longer use the vertical movement keys, but you can use  V  to make jumps. Press  TAB  again to turn gravity off.

### Fly Mode

In this older mode, moving the mouse to change the view works the same as in Walk mode, but the above direction keys ( W ,  A ,  S ,  D ,  E ,  Q  and the arrows) apply “thrust” in the respective directions, so you keep moving after releasing the key. Press the key repeatedly to increase your speed in that direction, or press the key for the opposite thrust direction to reduce your speed. You can roll the mouse wheel up to apply forward thrust, or roll it down to apply backward thrust.

Your current velocity vector automatically changes direction with you when you turn. Thus, you can apply a single burst of sideways thrust while facing an object, then, without applying any additional thrust, keep turning to face the object, and you will go right around it.

## Visibility Layers

Every object in the scene is assigned to one or more of 20 visibility layers.

Visibility layers have many uses:

• You can put scenery, characters, particles, and lamps in different layers, to help organize your scene.
• By changing which layers are visible, you can simplify your view of the scene and work with only one or two layers at a time.
• When rendering, only visible layers are included. You can use this to render your scene layer by layer, checking each layer separately.
• You can configure lamps to illuminate only objects in the same layer.
Left: Viewing layer 1 only.
Right: Viewing all 20 layers.

In Object Mode, you can tell which layers are visible by looking at the twenty small boxes located in the 3D View header between the Transform Orientation menu and the "Lock" button. The top row of boxes represents layers 1 through 10, with 1 being the leftmost and 10 being the rightmost. Similarly, the bottom row of boxes represents layers 11 through 20.

### Hotkeys

• To view just one of layers 1 .. 9, press  1KEY  ..  9KEY .
• To view just layer 10, press  0Key .
• To view just one of layers 11 .. 19, press  ALT + 1KEY  ..  ALT + 9KEY
• To view just layer 20, press  ALT + 0KEY .
• To toggle the visibility of one of layers 1 .. 9 without affecting the visibility of the other layers, press  SHIFT + 1KEY  ..  SHIFT + 9KEY .
• To toggle the visibility of layer 10 without affecting the visibility of the other layers, press  SHIFT + 0KEY .
• To toggle the visibility of one of layers 11 .. 19 without affecting the visibility of the other layers, press  ALT + SHIFT + 1KEY  ..  ALT + SHIFT + 9KEY .
• To toggle the visibility of layer 20 without affecting the visibility of the other layers, press  ALT + SHIFT + 0KEY .
• To make all layers visible at once, press  ~ . Press  ~  again to return to your previous layer visibility setting.
 The hotkeys in this section will not work if you've enabled numpad emulation in the User Preferences window. See the "User Preferences Windows" module for more details.

Note to AZERTY users:

On the AZERTY keyboard layout, the standard number keys are the &é"'(-è_çà keys. Do not use  Shift  unless you want to toggle visibility as explained below.

Holding down  Shift  while selecting a layer (by keyboard or mouse) will, instead of making only that layer visible, toggle the visibility. In this way, you can select combinations or to hide particular layers.

The key to press to select all layers at once differs by keyboard layout. It is:

•  ¬'  (the key under Esc) on UK keyboards,
•  ~  US,
•  ö  German, Swedish, Finnish and Hungarian,
•  ¨  Swiss German,
•  æ  Danish,
•  ù  AZERTY,
•  ø  Norwegian,
•  Ñ  Spanish,
•  ç  Portuguese,
•  "  Brazilian Portuguese,
•  ò  Italian, and
•  ё  Russian.

After pressing the aforementioned key, holding down  Shift  while pressing it again will restore the visibility settings you had before you made all layers visible.

When only one layer is selected, new objects are automatically assigned to that layer. When two or more layers are visible, new objects are assigned to the most recently visible layer.

If you want to count the polygons in your scene, the data is available in the Info Header.

As you can see in the above image, this scene has 507 vertices and 500 faces (polygons).

# Object Mode

## Introduction

In this module, you will learn some basics about operating in Object mode. This is normally the initial mode Blender is in when you open a new document. It is the mode where you operate on whole objects, rather than on their parts.

Many of the conventions involving selection and manipulation of objects or parts of objects apply to other modes as well, so this is a good place to become familiar with those conventions.

Cube selected in Object mode.

Open a new document, then confirm you are in Object mode by checking the mode menu.

Select the default cube by clicking on it with  RMB . You will see it framed in an orange outline.

## Object Origin

When you select an object, you will notice a round dot appears, normally in the middle of the object, the same orange-yellow as the rest of the selection.

This is the object’s origin. It is the reference point for the object’s local coordinate system. Certain kinds of edits to the object can cause this origin to end up at a position well outside the object. If that happens, operations like transformations applied with reference to the origin may not behave as expected. However, Blender has capabilities to deal with this. They will be explained when you need them.

## Multiple Selections

You can select more than one object at a time. With the cube still selected, change your view until you can see both it and the default lamp. Select the lamp by clicking on it with  SHIFT + RMB , so both it and the cube are selected. You will notice that the lamp takes on the orange-yellow colour, but the cube now has a more reddish highlight.

The active object is the last one selected. Other objects can be part of the selection, but the reddish-orange highlight indicates that they are not active. The Properties window shows properties for the active object, not the entire selection, although operations in the 3D view like moving and deleting objects will affect the entire selection. Some operations (like parenting, which you will learn about later) set up a special relationship between the active object and the rest of the selection, so for these, the order of selection of objects becomes important.

You can remove the active object from the selection with  SHIFT + RMB ; the small spot indicating the origin of the object’s geometry stays highlighted in the yellow-orange colour, even though the rest of the object loses the selection highlight. If you do this to an inactive object, it will make that object active.

Pressing  CTRL + I  inverts the selection. i.e. it deselects what was previously selected, and selects everything else instead. It does not change the active object.

## Selecting Obscured Objects

If multiple objects lie under the mouse, you can choose which one to select by clicking  ALT + RMB : this will bring up a menu listing the names of the selectable objects.

Alternatively, you can add an object to the current selection, or remove it from the current selection, by clicking  ALT + SHIFT + RMB  and selecting it from the menu.

On Ubuntu 16.04 LTS, it appears that  ALT + RMB  has the same effect as  RMB  on a Window's title bar. But  ALT + SHIFT + RMB  does the trick of Selecting Obscured Objects.

## Selecting Everything and Nothing

Pressing  A  does one of two things: if anything is selected, it clears the selection (i.e. selected objects are no longer selected). But if nothing is selected, then it selects everything. You will often see instructions to press  A  either once or twice, to ensure that either nothing is selected, or everything is selected.

## Hiding Things

When working on a complex model or scene, things are likely to get cluttered, making it hard to see the specific part you’re working on. It is possible to hide objects, so they no longer appear in the 3D view. Select the object(s) you wish to hide, and press  H . This is purely a convenience for working in the 3D view, i.e. hidden objects remain unchanged when you render them.

Pressing  SHIFT + H  hides everything except the current selection. This is a quick way to remove the clutter and narrow the view to the objects of interest.

Pressing  ALT + H  brings back all hidden objects and selects them. If you lose track of what is hidden and what is visible, press this to bring everything back.

## Local Versus Global View

Local view is another way of selectively hiding parts of the scene. Pressing  NUM/  (no substitute key provided for emulated numpad) hides everything that is not selected, and automatically zooms in or out as necessary so the selected objects fill the 3D view. Pressing  NUM/  again, restores the items to the normal global view.

This differs from simple hiding with  H  in that a render done in local view only shows the objects currently visible in that view. In particular, if your lights are excluded from the local view, you are liable to see black blobs in place of your objects.

How do I determine the viewing mode? Look at the at the words in the upper-left corner of the 3D view. They indicate your current view orientation and perspective settings (e.g. “User Persp”). If the word “(Local)” appears at the end of the string, you are in local view. Otherwise, you are in global view.

## Border Select (Box Selection)

A quick way to select many objects at once is with the Border Select (box selection). Press  B  to activate it. You will see a pair of dotted crosshairs appear centred at the current mouse position. Drag diagonally with  LMB  to mark a selection rectangle, then release the  LMB . Everything within the rectangle will be added to the selection. If you didn’t mean to engage box-selection mode, pressing  ESC  exits border select mode.

Alternatively, to remove things from the current selection, after pressing  B , drag the selection rectangle with  MMB . When you release the mouse button, everything in the drawn box will be deselected.

## Circle Select (Brush Selection)

Another way to select several objects at once is with the Circle Select (brush selection), engaged by pressing  C . In this mode, clicking or dragging on objects with  LMB  adds them to the selection, while  MMB  removes them from the selection. Thus the mouse becomes a brush that you can use to “paint” objects in or out of the selection.

The circle showing the size of the brush can be adjusted with the mouse wheel. This allows you to use a broad brush for selection of lots of objects at once, or a finer one for better control.

Clicking  RMB  or pressing  ESC  terminates Circle Select mode.

## The Manipulator

Manipulator transformation buttons & orientation menu
Manipulator—translation
Manipulator—rotation
Manipulator—scaling

The manipulator appears in the middle of the selection. There are three kinds of manipulator as shown in the illustrations. It can be used to apply translation (position changes), rotation and scaling (size changes) to objects. Its appearance changes according to which of these functions are enabled. You can click on the menu transformation buttons that appear when the manipulator is visible, to choose a single transformation, or shift-click to enable more than one simultaneously. You can toggle the visibility of the manipulator with  CTRL + SPACE , or by clicking the menu button with the red, green and blue arrows.

Transform orientations: the “Orientation” menu governs how the axes of the manipulator are aligned, with the default “Global” corresponding to the global coordinate system. Other useful options are “Local”, which corresponds to the local coordinates system of each object, and “View”, which is always aligned to your view.

To demonstrate this, click on the camera with  RMB  so that it is the only object selected. Set the manipulator to do only translations (blue arrow button is selected in menu), and ensure the orientation is set to “Global”. Drag any of the manipulator's coloured arrows with  LMB  to move the camera in the corresponding direction.

Now switch the orientation to “Local”. You will see the manipulator arrows re-orient themselves. Note that the Z-direction (blue arrow) is now in the direction of the camera view. The local co-ordinates of the camera have the optical axis of the camera running along the Z axis. By default, that is pointing towards the cube object.

The cube, by default, has its own local Z-direction running vertically.

With the manipulator orientation still set to Local, add the cube to the selection with  SHIFT + RMB . You will see the manipulator move so it is in the centre of the selected objects. It is now between the camera and the cube. Now if you drag the manipulator Z axis arrow with  LMB , each object will move along its own version of that axis. The camera moves towards or away from the cube and the cube rises or falls.

Switch the orientation to “Global”, and try dragging a manipulator arrow again. This time, both objects will appear locked together and will move in the same direction, along the same (global) axis.

## Transformation Hotkeys

The manipulator is not the only way to apply transformations to objects. That can also be done via keyboard shortcuts.

Hide the manipulator to reduce clutter. Select the cube, and only the cube, with  RMB . Now press  G  to Grab the object. The selection outline around the object turns white, as it did when you were dragging with the manipulator, except this time, you didn’t press any mouse buttons. Now move the mouse without pressing any buttons, and you will see the object move along with it. Press  LMB  or  ENTER  to terminate the movement and leave the selected object at the new position, or  RMB  or  ESC  to cancel the operation and leave the object at its original location.

Similarly, use  R  to Rotate the object, and  S  to Scale it.

You can constrain the movement to particular axes by pressing the appropriate axis key. For example, press  G  to start moving the cube again, then press  X  and you will see a bright colored line appear parallel to the global X-axis. Now when you move the mouse, the cube will move along only that colored line. Similarly  Y  and  Z  constrain movement to the Y and Z axes respectively. The colored lines that appear are a brighter reddish, green or blue that correspond to the red, green or blue lines for the X, Y or Z axes, respectively.

Transform orientations: to constrain the transformation to a different set of axes, press the constraint key twice. The coordinate system used depends on the selection in the Transform Orientation menu:

• Local or Global — the transformation happens in the object’s local coordinate system.
• View — the transformation is aligned to view coordinates.

For example, with the default “Global” selection from this menu, select the camera with  RMB , press  G  to move it, then press  Z  twice, and you will see the coloured line orient itself along the direction of view of the camera.

The axis constraints also work with scaling, and rotation (which only happens around the specified axis).

You can also constrain movement and scaling to happen along two axes, but not the third one, by holding down  SHIFT  when typing the axis constraint. For example,  G  followed by  SHIFT + Z  will constrain movement to the global X-Y plane (i.e. any direction except along the Z-axis). To constrain movement to the local X-Y plane, type the contraint twice:  G   SHIFT + Z   SHIFT + Z .

Here’s a summary of what the transformation hotkeys do, with and without constraints:

Key without constraint followed by axis followed by  SHIFT -axis
G  moves in plane perpendicular to view direction moves along axis moves in plane perpendicular to axis
S  scales uniformly along all axes scales along axis scales uniformly in plane perpendicular to axis

In addition, the hotkey sequence  R   R  enables free rotate, i.e. the object can rotate around all three axes as you move the mouse.

### Transforming by Numbers

Sometimes you need to position things accurately, using calculated numbers, instead of estimating by eye. Blender can do that too. Simply type the number after the transformation hotkeys before pressing  ENTER  to confirm the operation. For example,  G   X   1KEY   ENTER  will move the selection by 1 unit in the positive X direction.  G   X   −KEY   1KEY   ENTER  will move by 1 unit along negative X. Decimal points are allowed, thus  S   0KEY   .KEY   5KEY   ENTER  will scale the selection by a factor of 0.5, or 50%.

Rotation works similarly, using degrees clockwise around the selected X, Y or Z axis.

Yet another way is shown at right, in the Transform panel that appears at the top of the Properties shelf (press  N  to toggle its visibility at the right side of the 3D view). Here you can see the existing transformations values. You can drag the sliders to change them, or click on them and enter new values.

## Choosing the Pivot Point

When you do a scaling or rotation operation, you can choose the pivot point, which is the central origin point that remains unaffected by the operation. By default this is the “Median Point”, or centre point of the selection, but the Pivot Point menu lets you choose some other options. For example, select both the cube and the camera, and rotate them ( R ). By default they will rotate around their common centre. Now go to the Pivot Point menu and choose “Individual Origins” and rotate your two selected objects with  R  again, and you will see each one now rotates about its own centre, rather than the common one.

Another useful pivot option is “3D Cursor”, which places the transformation origin at the 3D cursor location.

Finally, the button with three dots and a double-headed arrow immediately to the right of the one that pops up the Pivot Point menu is titled “Manipulate center points.” Selecting this means transformations do not rotate the actual objects themselves, only their positions. To see the effect, you need to choose a pivot point that is not the object’s origin. Now try rotating the object. You will see its centre describes an arc around the pivot point, without changing the object's orientation. Think how the seats in a Ferris Wheel rotate around the wheel's pivot, yet still maintain their orientation.

Similarly scaling will change the distance between the chosen pivot point and the object’s origin, but will not affect the size of the object itself. A bursting firework scales rapidly in this way.

Why can’t I rotate or scale objects? One pitfall you might encounter is that you select an object, try rotating with  R  or scaling with  S , and nothing happens, though moving with  G  still works. It’s quite likely you have the “Manipulate center points” button active when you didn’t mean to. Check if it’s active, and click it to deactivate if so.

Hotkeys — there are keyboard shortcuts for all the above options:

Pivot Option Key
Active Element  ALT + .KEY
Median Point  CTRL + ,KEY
Individual Origins  CTRL + .KEY
3D Cursor  .KEY
Bounding Box Center  ,KEY
Toggle Manipulate Center Points  ALT + ,KEY

## Basic Camera Technique

The camera view  NUM0  is very useful for making adjustments to your camera while getting continuous feedback on how the render will look. This view shows a framing rectangle covering the area that will appear in the render, surrounded by a passepartout which gives a darkened view of the surrounding part of the scene. You can use the mouse wheel to zoom in and out, adjusting how much of your view is the rendered area and how much is passepartout.

In this view, use  RMB  on the framing rectangle to select the camera, and it will show the usual orange-yellow highlight. The manipulator will not appear even if enabled, so you must use the transformation hotkeys to perform camera transformations.

Use  G  to move the camera around parallel to the view plane. Since the view stays locked to the camera, you will see the scene move in the direction opposite of what you might expect.

The camera’s local Z-axis lies along its direction of view. This allows useful operations like  G   Z   Z  to move the camera in or out without affecting the direction in which it’s pointing. Also the X axis runs left to right in the camera view so rotating around X  R   X   X  will adjust the up-and-down pitch angle. Rotating around the vertical Y axis  R   Y   Y  will change the yaw (left-right) angle, and you can rotate around the optical axis of the camera using  R   Z   Z  to produce an effect of rolling the view around the visual axis.

Another useful technique is to position the 3D cursor at a point of interest, set the pivot point to the 3D cursor, then rotate the camera about a global axis, like the global Z-axis ( R   Z ), to adjust the angle of view while keeping the same objects in view, and without altering the distance of the camera from the point of interest. In real life you'd get that effect by walking in a circle around your subject with your camera mounted on a Steadicam rig.

Scaling the camera object changes its size as shown in the 3D view, but has no effect on the actual render. Regardless of what axis constraints you try to apply, the camera object will always scale uniformly along all axes.

You can also use Fly mode  SHIFT + F  in camera-view mode to fly around the scene, taking the camera with you.

Another choice for moving your camera in Camera View is to bring up the Properties panel ( N ) and, in the View section, tick the box next to Lock Camera to View. Now you will be able to use the  MMB  to "move objects" just as you move things around in other views such as the 3D view. Holding down the  MMB  and dragging will rotate,  Shift + MMB  will allow you to "move the object" around in the view (panning), and the scroll wheel will allow you to "move the object" closer or farther from the camera. You are actually moving the camera with these manipulations and not the object(s) themselves.

 Scaling the Camera: You can scale the camera object with  S  as you can most other objects. However, this has no effect on what is seen with that camera. Think of it as strictly a cosmetic thing to make the camera object easier to spot (if it’s too small relative to other objects in the scene), or scale it down to keep it in proportion when working with smaller objects. Another way of changing the displayed size of the camera is to look in the Camera data context in the Properties window, in the Display panel. Here there is a Size field that you can use to increase or reduce the size of the camera

Select the cube with  RMB  again. Press either  X  or  DEL  and, after confirming the popup, the cube disappears! It has been deleted from your scene. Unlike mere hiding, it really has disappeared. Press  CTRL + Z  to undo your last operation, and it reappears.

Click with  LMB  to position the 3D cursor away from the default cube. Press  SHIFT + A  to bring up the Add menu, go to its Mesh submenu, and add another cube to the scene. Again, undo with  CTRL + Z , and you are back to a single cube again.

Now press  CTRL + SHIFT + Z : this will undo the undo, and redo the last operation you undid, bringing back the second cube.

Try adding a third cube. Now  CTRL + Z  should undo that and take you back to two cubes, and pressing  CTRL + Z  again should undo the addition of the second cube, taking you back to one. Try  CTRL + SHIFT + Z  at this point to restore the second cube, then  CTRL + SHIFT + Z  again to restore the third one.

Blender remembers up to the last 32 things you did (depending on the limit set in your user preferences) in its undo stack. You can go backward and forward through it with  CTRL + Z  and  CTRL + SHIFT + Z .

Sometimes you want to perform an action repeatedly. To repeat the last action, type  SHIFT + R .

## Assigning Layers

Earlier, you learned about showing and hiding layers in the 3D view. To assign layers for selected objects, press  M . The same keyboard shortcuts apply here as when choosing which layers to display, i.e.  1KEY  for only the first layer,  2KEY  for only the second etc,  SHIFT + 1KEY  to include/exclude the first layer and so on.

After assigning an object to a different layer, it disappears! If this happens to you, it’s because the layer(s) you assigned to the object, and the layer(s) you currently have visible in the 3D view, have nothing in common. Simply change the visible layers to include at least one of those you assigned the object to, and it will reappear. For example, if currently only layer 1 is visible, and you assign an object to only layer 2, it will disappear, but reappear when you change the visible layer to layer 2.

## Object, Action, Settings

Bring up the Add menu again ( SHIFT + A ). This time, add a new cylinder mesh to the scene. Look to the left of the 3D view, in the Tool Shelf (toggle its visibility with  T  if it’s not visible), at the bottom you should see a new panel has appeared, titled “Add Cylinder”. Near the top of it is the “Vertices” number, initially defaulting to 32, which gives a fairly round-looking cylinder. Reduce it to 6, and adjust the view as necessary to get a good view of your “cylinder”, and you will see it is now a hexagonal prism. Change the number of vertices to 3, and it becomes a triangular prism.

This is an example of an important user-interface convention that runs right through Blender: first you select the object you want to perform an operation on as appropriate (not applicable here because we are creating a new object), then you perform the specified action with some default settings, and finally you adjust the settings to give the exact result you want. This way, instead of getting a popup before the action is performed, into which you have to put the right settings and hope they will give the right result, you get to interactively adjust the settings and immediately see the results, without having to continually redo the operation and deal with popups.

# Meshes and Edit Mode

Blender 3D: Noob to Pro/Mesh Edit Mode/

Open a new Blender document. Delete the default cube, and add a “UV Sphere” mesh. In the “Add UV Sphere” (Picture shows Ico Sphere) panel which appears at the lower left of the Toolshelf (press  T  to make the Toolshelf visible if it’s not), set both the Segments and Rings to a low number, e.g. 8. The result will be very angular, as shown to the right, not round like you would expect a sphere to be.

Press  F12  to do a quick render. The 3D view will be replaced with the UV/Image Editor view, showing the rendered image, as at right. Press  F11  to return to the 3D view .

Select the sphere object ( RMB ). Now look in the Toolshelf for the shading buttons: , and click on “Smooth”. Now try a new render with  F12 .

As you can see, the surfaces of the object look a lot smoother and curved, even though the outline or silhouette is just as angular as before.

Return to the 3D view with  F11 . Ensure the UV sphere object is selected, and you are in Edit mode. Bring up the Properties shelf at the right side of the 3D view with  N  if it’s not already visible. Look for the Mesh Display panel, and find the settings for Normals. . If you check both icon boxes, the display of the UV sphere should change to look something like the image to the right.

Those spiky little lines are the normals; the green ones in the middle of each face are face normals, the blue ones protruding from each vertex are vertex normals.

In the physical theory of light, the normal is a line perpendicular to the surface of the object the light is hitting. When your eye (or the camera) C is positioned on a plane through the normal of a particular surface observing a certain surface point P illuminated by a coplanar light source L, a specific amount of light will be reflected and hence be registered by the camera depending on the physical characteristics of the surface. The observed intensity of reflected light is at a maximum if the angle C-P-L is divided into two equal halves by the normal.

In the real world, a lot of surfaces are curved or otherwise not flat. But a mesh can only be made up of straight edges and flat faces. So how can it represent an object with a curved surface?

When you added the UV sphere to your scene, you had the option of specifying how many segments and rings it was made from. The more of those present, the closer the geometry approximates a curve. However, the more there are, the longer the render will take, and the more memory the model will consume to hold information about all the extra vertices, edges and faces.

Which is where that “Smooth” shading button you clicked comes in. It applies a trick called Phong shading. Instead of doing the lighting calculation based on a normal for each face as the physical theory says you should, it starts with a normal assigned to each vertex, and interpolates the normal at each point on a face from the vertex normals at its corners, based on the distance at that point to those corners. The result fools the eye into seeing curved, rounded surfaces where there aren’t any.

This completely violates the laws of physics. To start with, how can you define a “normal” which is perpendicular to a point? But as you can see, the results look rather good, with relatively little extra computation involved, much less than actually generating all the extra geometry.

As you learn more about computer graphics, you will come across more tricks like this. Physically accurate modelling is still very difficult to do, even with modern computers, and the results may not look all that good. But by adopting a bit of lateral thinking that goes completely against physics, we can often, ironically, come up with much more realistic-looking results.

## Not So Smooth?

If you have been adding lots of vertices, edges and faces to your mesh, you may end up with discontinuities in smooth shading causing unsightly blotches, as shown to the right.

Assuming your mesh is constructed properly (e.g. no edges and faces cross each other in physically impossible ways), the most likely reason for this is the normals in the newly added vertices and faces are pointing the wrong way. To fix it, select the troublesome part of the mesh (or select the whole thing) in Edit mode, and press  CTRL + N  to recalculate all the normals. Re-render the scene to confirm the shading discontinuity has disappeared.

 Note the different meaning of  CTRL + N  in Edit mode. In all other modes, it opens a new default Blender document!

# More Mesh Editing Techniques

You previously scratched the surface of the tools that Blender provides for editing meshes. This page will introduce more of them.

Start with the default cube again. Select it and  TAB  into Edit mode. Press  SHIFT + A  to bring up the Add menu. Instead of all the submenus with all the objects you could add in Object mode, you will see only a single menu containing only mesh objects. Select another cube, and use  G  to move it away from the first cube.

If you  TAB  into Object mode, you will see that the two cubes look like separate, disconnected objects, but they are in fact one object, and cannot be selected separately in Object mode. You can  TAB  back into Edit mode, and make connections between the vertices of the two cubes, which you cannot do with separate objects. Therefore:

 A single mesh object can be made of separate, disconnected pieces.

If you have some part of a mesh selected, pressing  CTRL + L  will select all other parts of the mesh that are connected to the already-selected parts. In the above case of the object made up of two disconnected cubes, you can  RMB  on a single vertex of one cube, then use  CTRL + L  to select all the rest of that cube but not the other.

Another way to do linked selections is to simply move the mouse over some part of the piece you want to select, and press  L  to immediately select everything connected to that. Conversely,  SHIFT + L  will unselect everything connected to the vertex under the mouse.

## Separating and Joining Meshes

You can separate a part of a mesh into its own object. The part you are separating doesn’t have to be disconnected from the rest of the mesh. Simply select the part you want to separate in Edit mode, and press  P , and in the menu that appears, choose “Selection”. You will see the selected part immediately change to a reddish-orange highlight, indicating it is part of the object selection but not the active object.

Conversely, you can join two or more mesh objects into one. Select all the desired objects in Object mode, and press  CTRL + J , and you will see them all immediately take on the orange-yellow highlight indicating they are all the active object.  TAB  into Edit mode, and you can confirm all are editable as part of the same mesh object.

## Proper Extrusion

You previously discovered how to add whole new sections to a mesh with  CTRL + LMB . Blender also has a proper Extrude function, which lets you do this with a bit more control.

Start with the default cube, as usual. Go into Edit mode. Select just the top four vertices. Press  E  to start extruding, and move the mouse roughly along the direction of the Z-axis. You will find yourself dragging out a whole new face formed from four new vertices connected to the ones you previously selected. You will notice also that the movement of the newly-added part of the mesh is automatically constrained to be parallel to the Z-axis. Press  LMB  or  ENTER  to finish the extrusion operation.

Deselect everything. Now try selecting another four vertices of the original cube, say making up a face pointing along the X-axis. Now if you extrude these, you will see that the extrusion is automatically constrained to move only parallel to the X-axis.

A quirk of the extrusion function is that if you press  E  and then immediately abort with  RMB  or  ESC , the additional mesh piece is still created, but it is left in the same position as the original mesh. To really abort the extrusion, you have to undo it with  CTRL + Z .

### More Extrusion Options

ALT + E  brings up the Extrude menu, which gives you access to more options, depending on what you have selected:

• “Region”—extrude the entire selected area as one, exactly equivalent to  E .
• “Individual Faces”—if you have more than one face selected, then they are extruded separately. In particular, any edge common to two selected faces will give rise to two separate extruded edges, rather than one.
• “Edges Only”—extrudes only the edges; new faces are created only connecting the new edges to the existing ones, not between the new edges.
• “Vertices Only”—extrudes only the vertices; edges are created only connecting the new vertices to the existing ones, not between the new vertices, and no new faces are created.

## Edge Loop Selection

Edge loops are an important concept when constructing meshes. They are so important that Blender provides a shortcut for selecting an entire edge loop with one click:  ALT + RMB  on an edge or vertex that is part of the loop you want to select, and it will select the entire loop. Alternatively,  ALT + SHIFT + RMB  adds an edge loop to the selection; or, if the part you click on is already selected, it will deselect the entire loop.

For example, try experimenting with a UV sphere: every line of “latitude” and “longitude” in this mesh is an edge loop.

## Loop Cuts

Sometimes you need to add more vertices to the interior part of a mesh, perhaps to flesh in some detail. The loop cut function lets you add more edge loops between existing ones.

Ensure you are in Edit mode. It doesn’t matter what parts of the mesh are currently selected. Press  CTRL + R  to activate the Loop Cut function. You will see a magenta-coloured loop wrap itself around different parts of the mesh as you move the mouse. You can press  RMB  or  ESC  to abandon the operation at this point, or once you see the loop appearing around the correct part of the mesh, you can use  LMB  or  ENTER  to proceed. Now the magenta colour changes to the usual orange-yellow selection highlight, and will now restrict itself to sliding along this section of the mesh as you move the mouse. If you press  LMB  or  ENTER  at this point, you will end up with a new loop of vertices and edges at the last-shown point, while  RMB  or  ESC  will still create the new loop, but leave it positioned at the midpoint.

When the loop is still at the magenta stage, you can use the mouse wheel to increase the number of cuts to 2 or more. You can also type a number of cuts using  0KEY  ...  9KEY .

## Edge Loop Deletion

Conversely, you can get rid of edge loops as well, reducing the complexity of the surface without leaving holes in it. Select the edge loop (the quick way is  ALT + RMB  on a component edge or vertex as described above), then bring up the deletion menu ( DEL  or  X ) and select “Edge Loop”. The selected loop will disappear, and adjacent edges and faces will be merged.

## Subdividing Parts

A loop cut always cuts a complete loop. Alternatively, you can subdivide just a selected part of the mesh: make your selection, then press  W  to bring up the Vertex Specials menu, and select the top option, “Subdivide”. This will create one cut, but a panel will appear at the lower left of the Toolshelf ( T  to make it visible at the left of the 3D view if it’s not), where you can alter the number of cuts and other settings. This same option is also available on Edge Specials  CTRL + E .

Another option is the second one on the  W  menu: “Subdivide Smooth”. This one computes a Catmull-Clark interpolation to give more of a curve rather than a flat subdivision.

## Subdivision Surface Modifier

A modifier causes some change to the geometry of an object just before it gets rendered. The change does not affect the object as you view and edit it in the 3D view, or as it is stored in the document (unless you apply the modifier, which makes the change permanent). This allows you to create some complicated effects at render time, while the original mesh stays simple and easy to edit. Modifiers for the active object are applied and controlled in the Modifiers tab in the Properties window.

A subdivision surface modifier (also known as a “subsurf” modifier) applies the Catmull-Clark interpolation discussed above as a modifier. Being a modifier, it applies to the entire object, not just to selected vertices. But since the original mesh is preserved, you use it as a control cage to adjust the shape of the interpolated curve.

Start with the default cube selected in Object mode, as usual. Go to the Modifiers tab in Properties. When you select “Subdivision Surface” from the “Add Modifier” menu, a new panel appears as at right. Notice the two value sliders under the “Subdivisions” heading; 'View' controls the level of subdivision within the 3D view, while 'Render' applies to the actual render; the higher the number of levels, the closer to a curve the interpolated geometry becomes. Having two separate settings for working environment and render allows for faster operation in the 3D view, with the usual tradeoff of lower quality, while still allowing maximum quality for the final render.

 Keyboard shortcuts: Because the Subdivision Surface modifier is so heavily used, there is a set of hotkeys for adding the modifier to the current object if it doesn’t already have one, and setting the number of subdivision levels in the 3D view:  CTRL + 1KEY  ..  CTRL + 5KEY  for setting the view levels to 1 .. 5 respectively.

As soon as you add the modifier, the appearance of the cube should change to look something like at right (here shown with just one level of subdivision).

The upper part of the panel (from the “Apply” and “Copy” buttons upwards) is common to all modifiers. Note the X button at the right. Clicking it gets rid of the modifier. Notice also a group of 4 icon buttons in the middle, the leftmost two look like a camera and an eye. The icons are defined as follows (from left to right):

• Use the modifier during rendering
• Show the modifier effect in the 3D view
• Show the modifier effect in the 3D view in Edit mode (if this is unchecked and the previous one is checked, the modifier effect disappears while in Edit mode)
• Show the mesh as though the modifier were applied to it in Edit mode.

Unchecking the first one lets you disable the modifier without losing its settings. The remaining three can be handy if you’re trying to disentangle the effects of different modifiers during editing.

When the third button is enabled, the mesh will look like this in Edit mode. The original mesh remains highlightable and editable. A preview of the effect of the modifier is also visible, and responds immediately to any changes made to the original mesh. (Try moving some vertices around, and see what happens.)

The fourth button goes one step further and acts as if the modifier has already been applied, while allowing you to edit only those parts corresponding to the original mesh. (This button affects the behavior of the third button. It cannot be used independently, and may disappear if the third button is unchecked.)

## Sharpening the Curves

The subdivision surface modifier offers much more control over the resulting shape than might be apparent from above. For example, you may not want uniform curvature everywhere, you may want some parts of the shape to have sharper edges. This can be achieved in two ways:

• by applying a crease value to selected edges
• by strategic positioning of additional vertices in the control-cage mesh.

### Applying a Crease

Select the edges where you want the curve to be sharper. Press  SHIFT + E . Note how the curve gets pulled more or less closer to those edges as you move the mouse. The selected edges take on a magenta colour, indicating they have a nonzero crease value applied.

The crease value can be seen and edited in the Transform panel at the top of the Properties Shelf at the side of the 3D view (you can toggle its visibility with  N . Values can range from 0.0 (no crease, the default) to 1.0 (maximum sharpness of the edge).

For example, start with the subdivided cube example as above. Press  CTRL + R  to start a loop cut, and position the magenta outline something like this:

Press  LMB  or  ENTER  ...

... and move the mouse so the newly-added loop moves closer to one side of the cube. See how the subdivided mesh develops a sharper curve on this side?

To confirm the placement of the new loop, press  LMB  or  ENTER .

### Which to Use?

The basic principle is, the closer together the vertices are, the more control you have over the curve at that point. So the question is, do you just want a sharper edge, or do you want more detail? That will govern whether you need to add vertices, or just apply a crease to the existing edges.

# Quickie Lighting

Open a new default Blender document. Without doing anything else, hit  F12  to render the default cube with the default settings. The result should look something like the image to the right.

Note the lower left visible face of the cube is completely black because the default light is at the upper right.

Go back from the render to the 3D view ( F11 ). Now select (with  RMB ) the default light, and either delete it or move it to another layer (with  M ). Go to your World tab in the Properties window, and look for the Environment Lighting panel:

Check the box next to the title, and leave the “E:” (energy) value at its default 1.0. This gives us a pervasive, directionless light, illuminating all objects equally from all directions, which means there will be no shadows. Do another render, and it should now look like the image to the right.

See how we have gone from inky-black shadows to no shadows at all. In the real world, lighting is almost never perfectly uniform, and this variation of light and shade is important to help us distinguish details of the scene around us Without such variations, everything devolves into featureless blobs.

Now undo your deletion of the default lamp (or move it back to layer 1). Enable Environment Lighting again, but this time lower the Energy value to 0.1. Do another render, and it should now look like the image to the right. The shadowed face is still shadowed, but not enough to make it impossible to see any details it may have. This is usually the type of effect you want, unless you are aiming for really dramatic contrasts.

So the lesson is:

 A single light is rarely enough for a good looking scene.

As you learn more, you will find that it is common to use two or three lights, or even more, to ensure proper illumination of a scene. In simple tutorials, where no explicit details are given about lighting, you can probably get by with the default light, plus some environment lighting (as we added earlier) to soften the shadows.

# Quickie Model

In this module, you'll learn how to extrude and merge vertices of a mesh and how to save a model. This module also introduces the File Browser window type.

Your first model will be a house, which we will develop over the course of several modules. Here we will start with four walls and a pyramidal roof. Simple! Since you're going to use the default cube as a base, all you actually need to build is the roof!

Editing in Blender generally involves four steps:

1. Selecting an object to edit.
2. Activating Edit Mode on that object.
3. Selecting part(s) of the object to act upon.
4. Specifying the action(s) to be performed on those parts.

## Bring up the Default Cube

The default cube in Object Mode.
1. Launch Blender.

This should give you a perspective view of a scene containing three objects:

• a cube,
• a light source,
• a camera.

## Setting up the Viewport

It will be easier to work on the roof of your house in a perspective side view:

1. Press  Num3  to switch to a "perfect" right side view.
 Num5  puts the viewport into perspective only if it's not already in perspective. Otherwise,  Num5  switches the viewport back to orthographic view.

"Right Persp" will be shown on the top left of the 3D View. The "up" (Z) direction in the scene is now "up" on your monitor as well.

It will also help to zoom in a bit:

1. Make sure the 3D View window is active (which means your mouse cursor is in it).
2.  SCROLL  or press  Num+  a few times until the cube is about 1/3 the height of the viewport.

Because you just loaded the factory defaults, the 3D transform manipulator will be enabled. For mesh editing, it will help to turn the manipulator off:

1. Make sure the 3D View window is active.
2. Press  Ctrl + Space  to toggle the manipulator on or off.

Press  Tab  once. This puts you into Edit Mode on the selected object, i.e. the cube.

 If the lamp and/or camera were selected instead of (or in addition to) the cube, you wouldn't be able to enter Edit Mode. (Cameras and lamps are edited in a different fashion.)

Here's how the cube should look at this point:

Examine the 3D View header to verify Blender is in Edit Mode and Vertex select mode with Occlude background geometry "on".
 The Occlude Background Geometry button is only visible when Blender is in Edit Mode and the draw type is Solid, Shaded, or Textured.

The default cube is constructed as a mesh. Now that you're in Edit Mode, you can access the individual vertices, edges, and faces that make up the mesh. The default cube consists of eight vertices, twelve edges, and six faces.

Right now, all eight vertices are selected, so any vertex edits you make will affect them all. For instance, if you were to move a vertex, the other seven vertices would follow. In order to build a roof peak for the house, you need to alter just the four top vertices of the cube. To do that, you must change the selection so that only those vertices are selected.

1. Turn 'Occlude Background Geometry' off, so you can see all vertices. Note, in newer versions, this button is called "Limit Selection to Visible." It is one of the buttons to the right of transform orientation which is to the right of the mode select which should be currently set to "edit mode".
2. Deselect the bottom four vertices, one by one, using  Shift + RMB .

The picture to the right shows the cube (in right perspective view and occlude background geometry "off") with the correct vertices selected.

 Remember, if you make a mistake, you can undo your work step-by-step by pressing  Ctrl + Z .

Now you'll adjust the height of your house's ceiling. Activate the grab tool:

1. Make sure Blender is in Edit Mode, with the relevant part(s) of the object selected.
2. Make sure the 3D View window is active.
3. Press  G .

The 3D View header will be replaced by numbers: "Dx: 0.0000 Dy: 0.0000 Dz: 0.0000 (0.0000)".

You want to lower the ceiling without making the walls crooked. This is hard to do freehand, but happily the grab tool provides an option for doing just that.

With the grab tool activated:

1. Press  Z  to limit movement to the global Z-axis.
Now when you move the mouse pointer around, Blender will adjust the height of your ceiling without making the walls crooked. (You can also limit grabs to the X and Y axes and in many other ways.)

When your ceiling is the height you want, confirm the grab with  LMB  (or  Enter ).

## Extruding

Step 7: the extruded attic, ready to confirm

Now you're going to "add on" to your house by extruding. Extrusion begins by duplicating selected parts of an object. Then the new parts are pulled away from the old ones, with new faces and edges created as necessary.

1. Make sure Blender is in Edit Mode, with the top four vertices selected.
2. Make sure the 3D View window is active.
3. Press  E  to activate the extrude tool.
4. Restrict movement to the Z axis and move the mouse pointer upward.
5. When the attic is the height you want, confirm the extrude with  LMB  or  Enter .
 At the end of this process only the four new vertices (the upper corners of the attic) will be selected. The others (including the four that were originally selected) will not be selected.

 If you cancel an extrude operation without confirming it, duplicate vertices and edges have already been created. If this isn't what you wanted, use  Ctrl + Z  to undo the duplication.

## Merging

You can change the roof from a flat one to a pyramidal one by merging the vertices of the roof:

1. Make sure Blender is in Edit Mode, with the four top-most vertices selected.
2. Make sure the 3D View window is active.
3. Press  W  to bring up the Specials menu.
4. Select Merge. (You can also access this by pressing  Alt + M .)
5. The Merge menu should pop up, select At center.

A message should appear on the Info header saying that 3 vertices have been deleted, this is because in order to merge four vertices into one, three vertices must be deleted.

Your house now has a pyramidal roof!

Saving the .blend

We will be developing the house in later modules, so save your work now. To save the current scene in a .blend file:

1. Press  F2  (or select File → Save As). The active window temporarily changes into a File Browser window.
2. Navigate to the directory (folder) where you want to write the file by clicking  LMB  on directory names in the File Browser window. (Clicking on ".." will take you up one level.)
3. If you wish to name the file something other than "untitled.blend", type a filename in the text box to the left of the "Cancel" button. (The .blend suffix will be added automatically.)
4. Click  LMB  on the "Save File" button. As soon as the save operation is complete, the window will automatically revert to its former type.

### Saving Further Changes

Once you have saved your work to a file for the first time, you can save subsequent changes to the same file name by pressing  CTRL + S  and confirming you want to overwrite the existing file.

# Quickie Render

If you haven't completed the "Quickie Model" module, do so now. You will need the resulting model for this module.

Now that you've created your first model, you'll probably want to try rendering it. Your first render, with a single light source and only nine faces, should finish quickly. However, as your 3D scenes become more complex, you'll find that rendering can take a long time.

In this module, you'll render your quickie model and save the result in various file formats. You'll also learn how to aim cameras and create lamps.

## Rendering the Quickie Model

1. Launch Blender and load factory settings.
2. To load the house model from the previous module, select File → Open Recent, and select the file you saved. Alternatively, press  F1  or select File → Open, find the file, and open it. As soon as the operation is complete, the window will revert back to its former type.
3. Press  F12  or select Render → Render Image. This opens the Image Editor so you can watch the render progress.
If F12 is in use by the window manager...
• With the new Apple keyboard, use  Fn + F12  to avoid the Mac Dashboard.
• With Macintosh OS X 10.5, use  Alt + Fn + F12 .
• With Gnome, use  Alt + F12  to avoid the Gnome Search Dialog.

 You can stop a render in progress by pressing  Esc  any time the render window has the focus. Bear in mind this will stop the rendering of the current frame and abandon any partial results. Pressing  F12  will start rendering the image from the beginning again.

By default, pressing  F12  will switch to the UV/Image Editor window, and show your render there. You can switch back to the 3D view with  F11 . Pressing  F11  in the 3D view will switch you to the UV/Image Editor window without redoing the render, i.e. you will see the same image as last time.

## Aiming the Camera

If you don't get a picture of the house, or if the picture is not framed well, try moving or re-aiming the camera:

1. Press  Esc  to get back to Edit Mode, if needed.
2. Press  Num0  to take the camera's viewpoint.
3. Press  Shift + F  to put the 3D View window into camera fly mode.

In camera fly mode, you can:

• Pan and tilt by moving the mouse pointer up, down, left, or right.
• Accelerate by  SCROLL  forwards.
• Decelerate by  SCROLL  backwards.
• Press any key or button to exit fly mode.

(It works differently in version 2.70 and later, more like a FPS game with possibility to slide and so on, buttons are regular FPS controls)

When you're done positioning the camera, try rendering again.

## Lighting

If your cube is completely black, you may not have a lamp in the scene. Either the default lamp got deleted, or you're using a version of Blender that doesn't provide a default lamp.

1. Make sure Blender is in Object Mode.
2. Place the 3D cursor where you want the lamp to go; or add the lamp then immediately grab it, and move it somewhere else.
3. Press  Shift + A .
4. In the popup menu, select Lamp → Point.

## Saving the Render

Saving the scene (with  F2 , for instance) does not save any renders. Saving renders is a separate step.

1. Make sure you are in the Image Editor. If not press  F12  to render
2. Press  F3 . This temporarily changes the active window into a File Browser window.
3. Navigate to the directory (folder) where you want to write the file.
4. Type a filename in the text box (to the left of the "Cancel" button).
5. To the left of the window, choose your preferred file type.
6. Click  LMB  on the "Save as Image" button. As soon as the save operation is complete, the window will revert back to its former type.

## Renderer Selection

Blender offers a choice of different rendering engines for producing images. The menu for selecting from these appears in the Info window (the thin one that contains the menu bar at the top of the default layout). In most of these tutorials, you will leave this choice set at Blender Render. But it is worth knowing what other choices are available:

• Blender Render—the oldest renderer, commonly known as the Blender Internal renderer. Built into Blender right from its early days. Can still produce good results with the right tricks, but considered by the Blender developers to be antiquated and not worthy of continuing development.
• Blender Game—this is the renderer used by the Blender Game Engine. Designed to be fast enough for interactive use in a game, which means there are limitations in the quality of renders it produces. You also use this renderer to create rigid-body physics simulations.
• Cycles Render—for this and other choices, see Advanced Rendering.

## Render Control

The top panel under the Render tab in the Properties window shows 3 buttons and a menu. The first button renders a single frame, equivalent to  F12 . The other two buttons are more relevant to animations.

The “Display:” menu controls what happens when you press  F12 : the default “Image Editor” causes the 3D view to be switched to the UV/Image Editor showing the rendered image. “Full Screen” causes the UV/Image Editor display to take over the entire screen, while “New Window” makes it appear in a separate OS/GUI window (similar to how older versions of Blender used to work). Finally, “Keep UI” causes no changes to your window layout at all; you have to explicitly bring up the Image Editor with  F11  to see the rendered image.

## Render Image Dimensions

You can control the size of the image that Blender creates when rendering. This is specified in the “Dimensions” panel under Render properties. Apart from the menu at the top, the settings in this panel are grouped into two columns:

• The column on the left controls settings for a single image.
• The column on the right specifies additional settings for rendering a whole sequence of images as part of an animation. These settings will be discussed later.

At the upper left, under “Resolution:”, we have the dimensions in pixels of the image (the default settings are 1920×1080 as shown in the screenshot), plus an additional scale factor slider below (showing 50% by default). With these settings, the image will actually be rendered at (1920×50%)×(1080×50%) = 960×540. Having the scale factor is a convenience. Rendering smaller, lower-quality images is faster, which speeds up initial work on your model, but you'll want full quality for the final result. Instead of mentally having to work out numbers for render quality, you can simply set the resolution to full quality, and use the scale factor to reduce this to, say, 50% or 25% for interim work, then set it to 100% for the final output.

## Image File Formats

You set the format and location for saving rendered images in the “Output” panel under the Render properties.

In current versions of Blender, the default format for saving rendered images is PNG. This is a lossless format which has the option for alpha transparency (which means the sky background is replaced by transparent pixels—enabled by clicking the “RGBA” button). This is a good format if you intend to do further work with the image (e.g. in an image editor like Gimp or Photoshop), but the files can be large.

JPEG is a lossy image format, which means it throws away information that the human eye doesn’t see. This produces much smaller files than PNG, and is adequate if you just want to upload the render directly for use in a Web page or other such document, but is not the best choice if you intend to do further processing of the image. It also doesn’t support alpha transparency.

To change the render file format:

1. Switch to the Render tab in the Properties window.
2. Look for the “Output” panel.
3. Click  LMB  on the popout menu with the current file format.

# Enter the World

Blender 3D: Noob to Pro/World Settings/

# Understanding the Camera

## Real-World Cameras

Before discussing the camera in Blender, it helps to understand something about how cameras work in real life. We have become accustomed to so many of their quirks and limitations when looking at real photographs, that 3D software like Blender often expends a lot of effort to mimic those quirks.

When taking a photo with a real camera, a number of important factors come into play:

• the focus — because of the way lenses work, only objects within a certain distance range from the camera (the depth of field) will appear sharp in the image. Objects outside this range will begin to appear noticeably blurred, the blur getting worse the farther they are outside the focus range. The narrower the range of in-focus distances (the shallower the depth of field), the more quickly this blurring happens with objects outside it.
• the exposure time — how long the shutter remains open. The longer this is, the more light is captured, but also the more likely the image is to pick up motion blur from moving objects.
• the aperture — how wide the iris opening is. This is expressed, not as an actual distance measurement, but as a fraction of the focal length of the lens (loosely, distance between the lens and the image-capturing surface when the image is properly focused), written as f: thus, say, f/2.8 (“f over 2.8”, not “f 2.8”) is a larger number, hence representing a wider aperture, than f/8. A wider aperture increases the amount of light being captured without contributing to motion blur, but it reduces the depth of field. The extreme case of a pinhole camera has a very tiny aperture with infinite depth of field (no need to focus at all), but captures very little light, so it needs a very well-lit scene, a long exposure, or a very sensitive image-capturing surface.
• the sensitivity of the image-capturing surface to light. In the days of film cameras, we talked about film sensitivity (“fast” film being more sensitive to light than “slow” film). Nowadays, with digital cameras we talk about the gain of the light-amplification system. High-sensitivity film was more likely to produce a grainy image. In a somewhat similar manner, high light-amplification in a digital camera is more likely to produce a noisy-looking image under low-light conditions.
• the field of view — how much of the scene the camera can see at once. A wide-angle lens gives a wider field of view, but you have to be closer to objects to be able to see them, and there is greater perspective distortion. At the other extreme, a telephoto lens gives a very narrow field of view, but can take pictures of things from much further away. A wide-angle lens also has a shorter focal length than a narrow-angle one (remember that aperture is expressed as a ratio of the focal length f), therefore the telephoto lens is going to capture less light than the wide-angle one with the same aperture width. You may also have heard of the zoom lens, i.e. one with a variable focal length. It can be adjusted from a wide-angle mode to a telephoto mode.

As you can see, many of these different factors interact with each other. The brightness of the image can be affected by the exposure time, the aperture, the gain sensitivity and the focal length of the lens. Each of these have side-effects on the image in other ways.

Blender and other computer graphics software are, in principle, free of the problems of focus, exposure time, aperture, sensitivity and focal length. Nevertheless, it is common to want to introduce deliberate motion blur into an image, to give the impression of movement. Sometimes it is useful to introduce a deliberately shallow depth of field, blurring objects in the background in order to draw emphasis to the important part of the image, i.e that which is in focus.

Exposure (the total amount of light captured in the image) is also less of a problem in computer graphics than in real-world photography, because in computer graphics you always have total control over the amount and placement of lighting in the scene. Nevertheless, if you’re not careful, you can produce overexposed (bright parts losing detail by saturating to a solid, featureless white) or underexposed images (dark parts losing detail by becoming solid black).

The field of view issue arises from basic principles of geometry, and Blender’s camera is just as much subject to that as real cameras.

## The Camera In Blender

Here we are going to concentrate on the important issue of field of view.

You can change the field of view in two ways - move the camera closer to or farther from the scene (called dollying in film/TV production parlance), or change the angle of the lens (zooming). You do the latter in the Object Data tab in the Properties window (the Camera has to be selected by  RMB  in Object Mode, or the required tab will not be visible).

Perspective is the phenomenon where objects that are farther away from the viewer look smaller than those nearby. More than that, different parts of the same object may be at different distances from the eye, leading to a change in the apparent shape of the object called perspective distortion. The mathematical theory of perspective was worked out by Alhazen in the 11th century, and famously adopted by the Italian Renaissance painters four hundred years later.

Here are two renders of the same scene with two different cameras, to illustrate the difference.

This one moves the camera closer but gives it a wider field of view:

This one moves the camera back, while narrowing its field of view, to try to give the scene the same overall size.

The latter is like using a “telephoto” lens with a real camera. Notice how the wider field of view gives you a greater perspective effect. The boxes are all cuboids, with parallel pairs of opposite faces joined by parallel edges, yet there is a noticeable angle between notionally-parallel edges in both images, which is more pronounced in the upper image. That is what perspective distortion is all about.

### Specifying the Field of View

When you select a camera object, its settings become visible in the Camera Context in the Properties window, which should initially look something like at right.

Photographers are accustomed to working in terms of the focal length of the lens - longer means narrower field of view, shorter means wider field of view. But the field of view also depends on the size of the sensor (image capture area). Modern digital cameras typically have a smaller sensor size than the exposed film area in older 35mm film cameras. Thus, the focal length measurements have to be adjusted accordingly, in order to give the same field of view.

Blender allows you to work this way, by specifying the focal length in the “Lens” panel, and the sensor size in the “Camera” panel. It even offers a “Camera Presets” menu, which sets the sensor size for any of a range of well-known cameras.

Also, you might be doing compositing of your computer-generated imagery on top of an actual photograph. In which case, to make the results look realistic, you need to closely match the characteristics of the camera and lens that were used to take the photo. If you know the lens focal length and camera sensor size, it makes sense to be able to plug those values in directly.

But if you’re not doing photo compositing, but generating completely synthetic imagery, you might consider this a somewhat roundabout way of working. Why not specify the field of view directly as an angle?

Blender allows for this as well. From the popup menu in the Lens panel that says “Millimeters”, select “Field of View” instead, and the Focal Length field will turn into a Field of View field, showing the angle in degrees directly. This is much easier to relate to the geometry of the scene!

 Relationship between the two: If the width of the sensor is d, the focal length of the lens is f, and the angle of view is θ, then they are related by ${\displaystyle {\frac {d}{2f}}=\tan {\frac {\theta }{2}}}$.

In this module, you'll refine the house model you created two modules ago. In the process, you'll learn how to access Blender's predefined meshes and how to set a pivot point. You'll also learn how to select, extrude, delete, and subdivide the edges and faces of a mesh model.

To begin, set up Blender as follows:

1. Launch Blender and load the factory settings.
2. If you have a numpad, make sure NumLock is on.
3. Load the house model you created in the "Quickie Model" module.
4. If the 3D manipulator is active, disable it.
5. Adjust the viewpoint until you can clearly see two walls of the house and two sides of the roof.

Your house needs some ground to rest on. You can model the ground as an object in your scene. Blender has many predefined mesh objects built in. Happily, one of these is a flat, square surface.

Recall that new objects are added at the 3D cursor. Before creating the ground, you should position the cursor at ground level:

1. Select the house by clicking  RMB  on it.
2. Enter Edit Mode by pressing  Tab .
3. Select one of the bottom vertices by clicking  RMB  on it.
4. Bring up the Snap menu by pressing  Shift + S .
5. Choose Cursor to Selected.
6. Leave Edit Mode by pressing  Tab  so your ground is created as a separate object.
 There's an "Aligned To View" setting in the "Editing" tab of User Preferences which is off by default in Blender 2.5x. When this setting is on, the orientation of new objects depends on the current viewpoint. Pre-2.48a releases of Blender had "Aligned To View" on by default. If you've turned this setting on (or are using an old release) go to "top view" (by pressing  Num7 ) before creating the ground object.

Now create the ground object:

1. Activate a 3D View window.
2. Press  Shift + A .
3. Choose Mesh → Plane.
The scaled ground.

To enlarge (or scale) the ground object, use the scale tool:

1. Make sure Blender is in Object Mode.
2. Select the ground by clicking  RMB  on it.
3. Activate the scale tool by pressing  S .
4. Type  7key  to enlarge the ground 7x.
5. Press  Enter  or  LMB  to confirm and exit the scale tool.

## Scaling with a Pivot

Suppose you want to shrink the house by 50%. As you can probably guess, this would be done with the scaling tool. However, if you did so right now without the right pivot point, the reduced house would no longer rest on the ground. Blender scales (and rotates) objects around a pivot point, which by default is located at the median point (geometric center) of the selected object(s).

In order to scale the house while keeping its base on the ground, you need the pivot point to be at ground level. Since the 3D cursor is at ground level, you can do this as follows:

Origin to 3D Cursor Menu Item.
1. Make sure Blender is in Object Mode.
2. Select the house by clicking  RMB  on it.
3. In the 3D View header, click  LMB  on menu item "Object" and put the mouse cursor over Transform and select Origin to 3D Cursor from the pop-up menu. This can also be done with Ctrl+Shift+Alt+C, select Origin to 3D Cursor from the pop-up menu. (A.K.A. select "Object" which is just left of where you've been going into object mode/edit mode, as shown in the image. So Object>Transform>Origin to 3D Cursor)

The origin of the house is now at the center of the 3D cursor. If you scale the house, the place where the 3D cursor is located will remain fixed, and everything else will expand or contract from that point. The pivot is marked with an orange-filled circle. Do not mistake it for a selected vertex.

## Edge Selection

It is often useful to select edges instead of vertices.

The select mode buttons.
1. Make sure Blender is in Object Mode.
2. Select the house by clicking  RMB  on it.
3. Press  Tab  to enter edit mode.
4. Click  LMB  on the Edge select mode button in the 3D View header.

In Edge select mode, edges appear as orange or white line segments when they're selected and as black line segments when they're not.

Just as you selected vertices in Vertex select mode, you can now select (and deselect) edges in the same way as vertices. This is also the same for Face select mode.

If you have difficulty selecting particular edges with the mouse...

It may be because those edges are doubled. This can happen if you cancel an extrude operation and forget to undo the duplication. Here's a solution:

1. Switch to Vertex select mode.
2. Activate a 3D View window.
3. Select all vertices by pressing  A  once or twice.
4. Press  W  to bring up the "Specials" menu.
5. Choose Remove Doubles.

## Extruding Edges

You can extrude edges in much the same way as you extrude vertices.

Step 5

To add an overhang to the roof of your house, first move the pivot point to the peak of the roof:

1. Switch to Vertex select mode.
2. Select just the vertex at the peak of the roof.
3. Press  Shift + S  to bring up the Snap menu.
4. In the Snap menu, choose Cursor to Selected to move the 3D cursor to the peak.
5. Use the "Pivot" menu (located to the left of the 3D Manipulator button) in the 3D View header to change the pivot to "3D Cursor".
After step 2

Now extrude by scaling from that point:

1. Switch to Edge select mode.
2. Select just the four edges at the base of the roof.
3. Press  E  to activate the extrude tool.
4. Press  S  to extrude by scaling uniformly from the pivot point.
5. As you move the mouse pointer away from the pivot point, the roof of your house will expand.
6. When the roof is the size you want, confirm by  LMB  (or pressing  Enter ).
7. Press  CTRL + SPACE  to toggle the manipulator on then make the overhangs slanted by holding  LMB  on the blue arrow that appears in the center of the house, and dragging down.
After step 7

## Face Selection

It is often useful to select faces.

The select mode buttons after step 2
1. Make sure you're in Edit Mode on the house.
2. Click  LMB  on the Face select mode button in the 3D View header.

In Face select mode, the center of each face is marked with a small square. Faces appear as orange or stippled grey areas with orange edges when they're selected (depending on which face is active), and as grey areas when they're not.

Just as you selected edges in Edge select mode, you can now select (and deselect) faces:

• If any faces are selected, press  A  to deselect all faces.
• If no faces are selected, press  A  to select all faces.
• To select a single face (and deselect the rest), click  RMB  (or  Cmd + LMB ) on the center of the face.
• To toggle the selection status of a face (without affecting the rest), click  Shift + RMB  on the center of the face.
The three faces on the +X side, selected

Use these techniques to select all three faces (two roof and one wall) on the +X side of your house, as shown.

• This reader would like to remind others that the positive direction of the axis is the direction the arrows point.

## Extruding Faces

Just as you extruded edges to grow the roof, you can extrude faces to grow the entire house.

After step 6

To double the size of your house without changing the pitch of the roof:

1. With the three faces on the +X side selected, activate a 3D View window.
2. Press  E  to activate the extrude tool.
3. Press  X  to extrude along the X axis
4. As you move the mouse pointer in the +X direction, the +X half of your house will expand.
5. Press  2  to expand by exactly 2 Blender units. (If you scaled your house earlier, you must change this value accordingly, e.g. scaling by 50% means you press  1 .)
6. Confirm and exit the extrude tool by clicking  LMB  (or pressing  Enter ).

## Deleting Edges

After step 2

If you look closely at the model, you'll notice an extra edge connecting the seams between the two halves of the roof. To delete this edge:

1. Edit the house object in Edge select mode.
2. Select just the edge you want to delete.
3. Press  X  or  Delete .
4. When the "Delete" menu comes up, choose Edges.
 Deleting an edge automatically deletes any face(s) that include that edge.

## Subdividing Faces

In order to add openings such as doors or windows to the walls of your house, you'll need to subdivide the wall (vertical) faces into smaller faces.

After step 2

To subdivide each wall face into a 10x20 grid:

1. Make sure you are not in wire-frame mode (otherwise the occlude hidden geometry button will not appear)
2. Edit the house object in Face select mode.
3. Select all six wall faces of your house.
4. Press  W  to bring up the Specials menu.
5. Choose Subdivide.
6. Set the number of cuts to 9 in the Operator panel (also accessible through F6).
 In some versions of Blender other than v2.70, there may be a bug that prevents the subdivide function from operating properly.

You might be wondering why to make 9 cuts instead of 10, the reason is that in case of dividing a finite surface along one axis there will be always n-1 cuts to generate n single faces. Here the number of cuts is applied in 2 dimensions. So, if you count the number of faces on the subdivided walls, you will find a 10x20 grid. The reason why there are 20 faces instead of 10 lengthwise is because you doubled the size of the house along the X axis (lengthwise).

After step 6
Step 2
After step 3.2

Now you can extrude windows and doors:

1. Edit the house object in Face select mode.
2. Turn on the "Limit selection to visible (clipped with depth buffer)" (for old Blender versions "Occlude background geometry") option by clicking  LMB  on the toggle button in the 3D View header.
3. For each wall of the house:
1. Go to the perfect view for that wall:
•  Num1  for "front"
•  Ctrl + Num1  for "back"
•  Num3  for "right"
•  Ctrl + Num3  for "left"
2. Select faces where you want to create a window or door. An easy way to do this is by:
1. Deselecting all faces by pressing  A  once or twice.
2. Pressing  B  to activate the Border Select tool.
3. Clicking and dragging  LMB  to delimit a rectangular area.
4. After you release  LMB , all faces in the rectangular area will be selected.
3. Press  E  to activate the extrude tool.
4. Extrude inward 1/10th of a BU by typing  -.1  and confirming it with  Enter  or  LMB .

## Final Steps

1. Adjust the position of the lamp and aim the camera until you obtain a good render.

# Extruding a Simple Person

Your simple person will look like this.

In this module, you will model a simple human figure. Along the way, you will practice using extrusion and learn additional ways to select vertices, edges, and faces.

## Start a New Scene

2. Press  Tab  to edit the cube.
3. Scale the cube down 50% by pressing  S   .   5KEY   ENTER .

## Selection Methods

Just as you did for the house model, you will begin by selecting the top four vertices of the cube. This section presents six methods for doing so.

Ease of selection depends partly on the viewport settings and viewpoint. For greatest ease, you want a view in which the parts you are trying to select are both visible and close together.

For clarity, use a view of the cube in which all vertices are visible:

• Go to right side view with  Num3 .
• Disable the manipulator widget with  Ctrl + Space .
• Make sure the Limit selection to visible option is "off".

The picture on the right shows the cube with the correct vertices selected.

To begin, make sure you start in Vertex select mode.

### Border Select Tool

The border select tool selects things that lie in a rectangular region of the viewport.

1. Activate (place the mouse pointer in) a 3D View window.
2. Deselect all vertices by pressing  A .
3. Press  B  to activate the border select tool. Two dashed gray lines should appear, one vertical and one horizontal, forming a crosshair in the viewpoint.
4. Click and drag  LMB  diagonally across the area you want to select. The area will be outlined in dashed gray lines.
5. When you release the mouse button, the vertices inside the rectangle will be added to the selection.

Practice selecting the top four vertices this way. If you make a mistake, press  A  and try again.

### Circle Select Tool

The circle select tool selects or deselects things that lie in a circular region of the viewport.

1. Activate a 3D View window.
2. Deselect all vertices by pressing  A .
3. Press  C  to activate the circle select tool. A dashed gray circle should appear. note: Prior to Blender 2.5  B  B  twice.

When this tool is active, you can do various things:

• To move the select area, simply move the mouse pointer.
• To resize the select area, use  SCROLL  or  Num+ / NUM− ..
• To select all vertices within the circle, click  LMB .
• To deselect all vertices within the circle, click  MMB  or  Shift  +  LMB .
• To deactivate the tool, press  Esc  or  RMB .

Practice selecting the top four vertices this way. If you make a mistake, press  A  and try again.

### Lasso Select Tool

Like many graphics programs, Blender 3D has a lasso select tool.

1. Activate a 3D View window.
2. Deselect all vertices by pressing  A .
3. Click and hold  Ctrl + LMB .
4. Drag the mouse pointer in a loop around the vertices you want to select. As you drag, a dashed gray line will appear.
5. You can deselect with lasso by pressing  Ctrl + Shift + LMB .
6. Release the  LMB  when you're done.

### Vertex by Vertex Selection

You can select (or deselect) vertices one by one, as you did in the "Quickie Model" module.

1. Click  RMB  on a vertex to make it the only selected vertex.
2. Toggle the select state of additional vertices by clicking  Shift + RMB .

### Edge Select Mode

You can select (or deselect) edges one by one, as you did in the "Improving Your House" module.

1. Click  LMB  on the Edge select mode button in the 3D View header.
2. Select the top left edge of the cube by clicking on it with  RMB .
3. Toggle the select state of top right edge of the cube by clicking on it with  Shift + RMB .
4. Switch back to Vertex select mode by clicking  LMB  on the Vertex select mode button in the 3D View header.

After you switch back to Vertex select mode, all four vertices in the two selected edges are selected.

### Face Select Mode

You can select (or deselect) faces one by one, as you did in the "Improving Your House" module.

1. Click  LMB  on the Face select mode button in the 3D View header.
2. Select the top face of the cube by clicking on its center dot with  RMB .
3. Switch back to Vertex select mode by clicking  LMB  on the Vertex select mode button in the 3D View header.

After you switch back to Vertex select mode, all four vertices in selected face are selected.

## Extruding Limbs

The illustrations in this section are in front orthographic view, so:

• Use  Num5  (or View → Orthographic) to switch to orthographic view.
• Use  Num1  (or View → Front) to switch to front view.

### Region Extrusion

1. Make sure you're still in Edit Mode, with the top four vertices selected. (Only two will be visible in front ortho view.)
2. Activate the extrude tool by using  E  (or Mesh → Extrude Region).
3. Move the mouse pointer upwards. As you do, four new vertices will appear, each connected to one of the four that were previously selected.

The new vertices and their associated edges will move with the mouse pointer. You can lock them into place with  LMB  or  Enter ).

### Extruding a Leg

Suppose you want to extrude a region the same size as the default cube -- in other words, one Blender unit on a side.

1. Undo your previous extrude by pressing  Ctrl + Z .
2. Activate the extrude tool again by using  E  (or Mesh → Extrude Region).
3. This time, as you're moving the extruded vertices around, hold down the  Ctrl  key. You'll see that the new vertices will only move in multiples of a Blender unit. This is called snapping, and it makes it easy to extrude by exactly one blender unit. The size of the snapping depends on the zoom level; if you are zoomed out a long way from the object the snapping will be done in large increments and if you are zoomed in close you can snap in finer amounts.

Continue extruding until you have five cubes of equal size stacked atop one another. This will be one leg of your figure.

 Another way to extrude by exactly one Blender unit is to press  1key  while the tool is active. If you press  2key  when no tool is active, Blender will switch to the second layer, and your (first-layer) object will disappear. To make it visible again, press  1key .

 If you are not using Front Ortho view, the blender unit will be much larger than the cube. Switching to that view will allow for the proper size, although you can manually enter the extrusion as 0.4 units.

 Don't extrude any cube more than a unit at a time. You'll want those extra vertices, edges and faces later in this tutorial.

 If the mesh gets too big for your view, you can zoom out using  SCROLL  or  NUM−

### Extruding the Pelvis

1. Press  A  until all vertices are deselected.
2. Rotate the view (by dragging  MMB ) so you can see all four vertices on the right face of the top cube.
3. Select those four vertices.
4. Extrude twice to the right.

### Extruding the Rest of the Body

The same trick is repeated over and over to build the rest of our simple body.

 To speed things up, you may want to switch to Face select mode. In Face select mode, you can select a face with a single click.

1. Create a second leg by extruding down four times from the last cube of the pelvis.
2. Create the torso by extruding up five times from the middle cube of the pelvis.
3. Extrude to each side from the next-to-top cube of the torso to create arms. (Making sure there are five on each side. Refer to the picture on the top of the page)

To be safe, remove any double vertices you may have inadvertently created:

1. In Vertex select mode, press  A  until all vertices are selected.
2. With a 3D View window active, press  W  to bring up the Specials menu.
3. Choose Remove Doubles.

2. Make sure the viewport draw type is Solid. (Press  Z  if it isn't.)
3. Rotate the viewpoint and examine the body from every side (it might be useful to return to perspective view for this).
If any faces are missing...

This is easily fixed. To create a face:

1. Press  Tab  to go back into Edit Mode.
2. Select four vertices.
3. Press  F  (or choose Mesh → Faces → Make Edge/Face from the 3D View header).
• Note that you can also make edges with this tool if you select two vertices.

1. Move the 3D cursor to a point above the neck by clicking with the  LMB .
2. Adjust the cursor position in orthographic top, front and side views ( Num7 ,  Num1 , and  Num3  respectively) until the 3D cursor is about where the center of the head should be. It may help to use  Shift + S SnapCursor to Grid.
3. Make sure you're in Edit Mode with a 3D View window active. (If you create the head in Object Mode, it will be a separate object from the body, and changes to the body later in this tutorial won't affect the head.)
4. Create a sphere using  Shift + A MeshIcosphere.
5. Leave the default settings for subdivisions and size in the bottom left of the screen. (Note: Your computer may slow down if you set subdivisions above 6)

You should now have a small sphere at the top of the body. To make it more proportional to the body, resize it using the scale tool:

1. Make sure you're still in Edit Mode, with a 3D View window active and the head selected.
2. If necessary change the pivot point to Median Point.
3. Activate the scale tool by pressing  S  (or Mesh → Transform → Scale).
4. Move the mouse pointer until the head is the size you want.

You may also adjust its position using the grab tool:

1. Make sure you're still in Edit Mode, with a 3D View window active and the head selected.
2. Activate the grab tool by pressing  G  (or Mesh → Transform → Grab/Move).
3. Move the mouse pointer until the center of the head is where you want it.
 If you deselect the head and then decide that you want to select it again: Hover the mouse pointer over any vertex/edge/face. Press  L . In Edit Mode this will select all vertices that are linked to the vertex nearest the mouse pointer.

2. Make sure the viewport draw type is Solid. (Press  Z  if it isn't.)
3. Rotate the viewpoint and examine the body from every side. Make sure that the head connects properly to the neck.

You will continue working on your simple person model in the next module.

To save the scene in a .blend` file:

1. Press  ctrl  +  S  (or select File → Save).
2. Navigate to the directory (folder) where you want to write the file.
3. Type a filename in the text box to the left of the "Cancel" button.
4. Click  LMB  on the "Save Blender File" button.

Few real-life objects have perfectly sharp edges. People, in particular, consist of mainly smooth surfaces. How does one model a smooth object using flat faces and sharp edges?

In this module, you'll learn how to smooth a mesh by using subsurfaces and smooth shading.

You'll need the simple person model from the previous module. If you haven't done it, either go back and do it now or download the pre-made model from Yosun Chang's website at http://www.nusoy.com/blender.

If the model doesn't look solid, your Viewport Shading setting may be set to Wireframe. To switch to Solid shading:

1. Activate the 3D View window.
2. Press  Z .

## Subsurfaces

The sub surface modifier.

So far, all the meshes you've created have had sharp edges, giving them a faceted appearance like that of a cut diamond. To model a smooth object (like a human body) you might think you need a huge number of vertices and faces. Subsurfaces partly solves this problem by automatically subdividing a mesh into a finer mesh suitable for smooth rendering.

You subsurface in Blender by adding a subsurf modifier to an existing mesh object. A modifier is simply an algorithm (automatic process) which can be added to an object. (Blender modifiers are analogous to Photoshop adjustment layers.)

To get started, make sure Blender is in Object Mode, with only the simple person object selected:

1. If Blender is in Edit Mode, press  Tab .
2. To select the simple person,  RMB  on it.

To add a subsurf modifier to the selected object:

1. Click on the modifiers tab (wrench icon) in the Properties window.
2. Add Modifier → Subdivision Surface.

You could also add subsurf modifier by pressing  Ctrl + 1Key .

The object's appearance should immediately become more faceted and more rounded. In addition, several subsurface controls will appear in the Modifiers tab.

 The modifier has been added, but it hasn't actually been "applied" yet. (Applying a Blender modifier is analogous to flattening a Photoshop adjustment layer.)

If a few faces don't subsurf...

The model may include some double vertices. To get rid of these:

1. Edit the model in Vertex select mode.
2. Select all vertices.
3. Mesh → Vertices → Remove Double
4. Try again.
If Blender crashes when you attempt to subsurf an object...

You need to look in to upgrading (or possibly even downgrading) your graphics drivers. Having the right graphics driver can avert many problems.

What just happened? The default subsurf modifier (one level of Catmull-Clark) subdivided each face of the object into four smaller faces that are progressively angled. This softened the sharp edges of the original model where faces met at 90-degree angles.

### Controls

For this model, one level of subsurf isn't quite enough. To increase the number of levels to two, just increase the number in the text box directly underneath Subdivisions. The View setting controls the number of subdivision levels visible in the viewport. This is very useful when you have a high-poly scene, just decrease the number of visible subdivisions to speed up viewport action.

You can specify additional levels of subsurfing to be used during renders. For extra smooth renders, you might want three levels of subsurfing. Set this with the Render control immediately below the View control.

The Apply button applies the modifier to the mesh. Do not click it yet. We'll be playing with the model a bit longer before we apply the changes. While useful with some modifiers, applying a subsurf modifier produces a very complex mesh, and there's no need to do so here.

Remember that you can undo any accidental modifications with  Ctrl + Z .

Blender can combine a series of modifiers by stacking them. For this reason, the Modifier tab includes buttons for arranging and removing modifiers.

You can hide edges created by the modifier by activating the Optimal Display toggle button. The effect is especially clear with the Wireframe draw type.

You can edit the mesh in modified form (without actually applying the modifier) by activating the Adjust edit cage to modifier toggle button, a small button with a triangle and vertices, to the left of the Up/Down arrows (the arrows are for changing the position of the modifier in the stack) in the Modifier panel.

Try this out:

1. Press  Tab  to enter Edit mode.
2. Make sure Blender is in Vertex select mode.
Note that the vertices no longer lie on the surface of the object.
3. Activate the Adjust edit cage to modifier button.
Now all vertices lie on the surface of the object, and you can adjust the (modified) vertices directly. However, any additional vertices created by the modifier cannot be directly edited without applying the modifier.

You will be editing the boxy version of the simple person awhile longer, so before continuing, deactivate the Apply modifier to editing cage during Editmode button.

Your simple person after setting smooth.

Subsurfaces do a good job of smoothing out corners in meshes. Even with two levels of subsurfaces, however, the simple person does not look completely smooth; when viewed close up, it has a scaly appearance. This is because each face is flat shaded—shaded to resemble a flat surface—resulting in sudden changes in brightness at most edges. For a smooth object, you want smooth shading, which smooths out the changes in brightness.

1. Go to Object Mode.
2. Set the draw type of a 3D View window to "Solid".
4. In the Toolshelf on the left, look for a caption called Shading. Under it should be a button called Smooth.
All the mesh edges will be smoothed out, leaving no sudden changes in brightness. The faces blend smoothly into one another, making the edges nearly invisible. If the icosphere has not smoothed properly and is dimpled, enter Edit Mode by pressing  Tab , select all vertices (A) and recalculate the normal direction (CTRL+N). This is also available in the Toolshelf under Normals.
5. Click the other button under Shading in the Toolshelf, named 'Flat'.
The edges will reappear. Now you know the difference between Flat and Smooth.
6. Since the model looks better with smooth shading, click  LMB  on the "Smooth" button again.

Note that if you didn't have subsurf enabled, then the mesh wouldn't look much different. This is because smooth shading doesn't affect the mesh shape, it just changes how the computer draws the triangles.

Smooth shading also removes a lot of definition. A good way to get rid of this is simply to add a subsurf modifier like you just did. The modifier will not only require fewer vertices, but add definition.

Save your work. You will continue refining this model in the next module.

In this module, you'll edit a subsurfed mesh using the scale and grab tools, all the while improving your character.

You'll need the simple person model from the previous module. If you haven't done it, either go back and do it now or else download the pre-made model from Yosun Chang's website at http://www.nusoy.com/blender.

## Widening the Torso

To be realistic, the simple person's torso needs to be three times wider. In order to keep the torso symmetrical, you'll expand it by scaling both sides from a central point.

Select the sides of the torso:

1. Enter edit mode on the simple person.
2. In the 3D View header, set Face select mode.
3. From the 3D View header, choose Pivot → Median Point.
4. In the 3D View header, make sure Proportional Edit button is off.
5. Select the two faces on both the left and right sides of the torso, between the armpits and the waist.
 The cube icon toggles the visibility of certain components. When editing in solid mode, the vertices, edges and faces on the back side of the model are, by default, invisible. This feature can be toggled by clicking  LMB  on the Limit selection to visible (called in older versions, "Occlude Background Geometry") button in the 3D View header. Toggle it on and off a few times and observe how the back faces appear and disappear.

We will now scale the torso with the scaling tool:

1. Activate the 3D View window and press  S ,  X .
2. Adjust the amount of scaling. Either:
• Move the mouse pointer until the torso is the width you want.
or
• Press  3
3. Confirm and exit by pressing  Enter or clicking  LMB .
 Scaling faces causes adjacent edges and faces to move, due to their shared vertices. You cannot separate a face or edge from its vertices.

Continue selecting different parts of the torso and scaling them to get more practice using the above scaling methods.

## Bending the Arms

Removing the forearm

When you've got the basic shape of the torso, make the person hold up his hands. You'll do this by deleting the forearms and then extruding upward from the elbows.

Select both forearms:

1. Enter edit mode on the simple person.
2. In the 3D View header, set Face select mode.
3. With the 3D View window active, press  A  until all vertices are deselected.
4. Select the five faces at the end of the forearm.

Now erase them:

1. Press  X  to open the Delete menu.
2. Choose Faces.

The forearm will disappear, leaving a hole. Don't panic; we'll fix it later. Now to make the arm point upwards:

1. Select the top face of the last remaining "arm cube".
2. Extrude the region upward by two Blender units  E ,  Z ,  2  and confirm with  LMB  or  Enter .

(Newbie comment: on my system, using Blender 2.70a, you want E-2 above, not E-Z-2. Z-axis constraint is on by default, so pressing Z turns it off and causes trouble. Confirmed by second newbie in Blender 2.78.4.)

The hole in the elbow is caused by a missing face. To fill in the missing face:

1. Deselect all vertices.
2. Select the four vertices surrounding the missing face.
3. With the 3D View window active, create the face using either
• Mesh → Faces → Make Edge/Face
or
•  F
 If a Make Faces menu appears when you try to fill the hole, it may be that you have some doubled vertices. You can remove doubles by selecting the whole mesh in edit mode, then pressing  W  and in the appearing menu "Remove Doubles" and try again.

The new face should be smooth. If it isn't, make it so, using Mesh → Faces → Shade Smooth.

Repeat on the other side

Go through the same steps (erase, extrude, and fill) on the other arm. Be sure to deselect all vertices in the first arm before selecting any in the other arm. If you have difficulty making the arms symmetrical, undo your work and go through the steps simultaneously on both arms.

## Making Feet

To make feet for your simple person, you subdivide the ends of the legs and pull the front edges forward.

1. Edit the simple person in Face select mode.
2. Select the two bottom faces of the legs (front of the feet) by clicking  RMB  on the first and then  Shift + RMB  on the other.
3. Subdivide both faces, either with:
•  W  Subdivide
or
• Mesh → Edges → Subdivide

Each face gets subdivided into four smaller faces.

Now select the front edges and pull them forward:

1. Switch to Edge select mode.
2. Press  A  until no edges are selected.
3. Select the four bottom front edges of the soles (two for each feet) (where the toes should be).
4. Press  G  and limit movement to the Y axis.
5. Move the mouse pointer until the feet are the length you want.
6. Confirm and exit by pressing  Enter  or  Space  or clicking  LMB .
Congratulations! You now have feet.

When you're satisfied with the torso and limbs, you should do something about that head. A bit too spherical, isn't it? You can elongate it by scaling along the Z axis.

When scaling the head, you want to make sure that it stays connected to the neck.

First, place the 3D Cursor at the base of the head, where it meets the neck. An easy way to do this is as follows:

1. Go into Vertex select mode.
2. Make sure the Limit selection to visible option is "off".
3. Select the vertex at the base of the head using  RMB .
4. Snap the cursor to this vertex using  Shift + S  Cursor to Selected

1. Hover the mouse over a vertex/edge/face of the head
2. Press  L  to select all parts linked to that part.
 This works even when the head and body meshes overlap, so long as they aren't linked together anywhere.

Tell Blender that you want to pivot around the 3D Cursor by changing the pivot point to 3D Cursor on the Pivot menu (the small button located to the left of the 3D Manipulator button).

Now scale the head along the Z-axis, using the scale tool ( S , scaling by 1.5 should be about right).

You'll need this simple person later, so remember to save your work!

# Spinning a Simple Hat

In this module, you'll create a hat for your simple person. Along the way, you'll learn how to use the Spin tool and use layers.

## Creating a Generatrix

For future convenience, you'll create the hat as a new object in the scene containing the simple person. If you haven't created the simple person, either go back and do it now or else download the pre-made model from Yosun Chang's website at http://www.nusoy.com/blender.

Start by changing layers to layer two, then add the basis for your hat:

1. Make sure you're in Object Mode (so that a new object will be created).
2. Click  LMB  on the second little square, this will make the viewport display layer two. (The top row is for layers 1 to 10, the bottom for 11 to 20, so layer 2 is immediately to the right of layer 1; layer 6 is across the space from layer 5.)
3. Go to orthographic front view by pressing  Num1 .
4. Create a mesh circle at the cursor, by activating the 3D View window, pressing  shift  +  A  and choosing Mesh → Circle.
 The new circle will probably look more like a line segment than a circle. If so, it's because you're viewing the circle edge-on.

The new mesh object doesn't actually have to be a circle. You could use any sort of mesh object here because you're about to reshape it into a custom 2D mesh (called a generatrix) that describes the profile of your hat. More precisely, the generatrix describes one side of a vertical cross-section through the hat. You'll want your generatrix to have a slope; it should be higher on one side (which will become the top of the crown) than on the other (which will become the brim).

1. The newly-created mesh should be selected. If it isn't, select it by clicking  RMB  on it.
2. Press  Tab  to edit the mesh.
3. Activate Vertex select mode.
4. Press  A  until all vertices are selected.
5. Press  X  to erase all vertices.
 Some users are confused as to the purpose of creating the mesh only to delete it afterwards. The point of this process is to create a new "blank" object which you can then shape into a hat.

Now draw your generatrix, starting with the brim and sloping upwards toward the top of the crown:

1. Make sure you're still in orthographic front view.
2. Press  Ctrl + LMB  to create the first vertex.
3. Press  Ctrl + LMB  to one side of that vertex to extrude another vertex, connected to the first by an edge.

(If this doesn't work, make sure you are in vertex select mode.)

Keep adding vertices until you're satisfied with the shape of your generatrix. You can always undo using  Ctrl + Z  or go back and adjust the positions of particular vertices using the grab tool.

The mesh is then spun around an axis perpendicular to the viewplane. You want to spin around a vertical axis, so press  Num7  to switch to top view.

## Spinning the Hat

The spun hat, drawn as wireframe in orthographic front view.

Now, let's actually spin the hat:

1. Move the 3D cursor to the vertex you want to spin around by pressing  LMB  on it. You can also use the snapping tool for positioning the cursor more precisely by pressing  Shift+S  after selecting that specific vertex. Cursor to selected positions the cursor.
2. Press  A  to select all the vertices. The Spin control only spins vertices that are selected.
3. Press  Alt+R  to activate the Spin tool.
• The Spin tool is also available in the Tool Shelf under Add
If you spin the hat in front view, your hat will be flat. You have to spin the hat in top view.

You should now see 90° of a generatrix! To spin your hat all the way round, press  F6  or look in the Operator Panel just below the Tool Shelf. There should be an input slider named Angle, change this value from 90 to 360. There should also be a slider called Steps, increase the value from 9 to 15.

If your hat has a large hole in the center, you must have accidentally moved the 3D cursor away from the vertex you picked in step 1. Try again.

Remember that if you spin an object 360° there will be a double row of vertices at the row of vertices you spun. To fix this, press  A  to select all vertices, press  W  and select Remove Doubles. Note that this will only work in vertex select mode.

You may also want to merge the vertices at the top of the hat. Do this by selecting all the vertices at the top with  C  and pressing  Alt + M At Center. You may have to do this twice as some vertices might be beneath each other.

If the mouse pointer changes to a question-mark (?)...

You have more than one 3D View window, so Blender is asking which window to perform the spin in. Click  LMB  on the window that is showing top view.

The finished product!

You'll probably have noticed that normal hats aren't usually as faceted as yours! To change this, first press  Tab  to go back to Object mode then change the shading to Smooth (available on the Tool Shelf). If there are unexpected black marks, try recalculating the normals.

1. Switch to Edit mode and open the Mesh menu in the 3D View Header.
2. Normals → Recalculate Outside.

Next, add a Subsurf modifier to the hat and set the subdivisions to two, as you did in the "Detailing Your Simple Person 1" module.

1. Click on the modifiers tab (wrench icon) in a Properties window.
2. Add Modifier → Subdivision Surface.

Save your work. You'll need this scene for the next module.

# Putting the Hat on the Person

Once you're satisfied with the shapes of individual objects, you'll want to combine them into a coherent scene. You do this in Object Mode.

In this module, you'll learn how to move objects to and from layers. You'll also learn how to rename and parent objects, and you'll get an introduction to Outliner Windows.

You'll need the person-and-hat scene from the previous module. If you haven't done it, either go back and do it now or else download the pre-made model from Yosun Chang's website at http://www.nusoy.com/blender.

## Adjusting an Object's Median Point

The person that you (yeah you!) made with the origin in his geometric center.
2. Make sure Blender is in Object Mode.
3. Switch to Layer 2, select the hat and press  M . A dialog box will pop up for you to choose which layer to move it to. Either press 1 (the number on top of the keyboard, not the numberpad) or select the first box in the popup.
4. Select the person you made earlier.

Just as you did in Edit Mode, you can specify the pivot for rotating and scaling objects in Object Mode. If you just finished the previous module, the pivot is probably set to "3D Cursor". If so, change it back to "Median Point".

In Edit Mode, the "Median Point" for pivoting is the geometric center of all selected vertices, edges, or faces. In Object Mode, however, it's the origin of the selected object's local coordinates, indicated by an orange dot. In other words, the origin might lie far from the object's geometric center.

You can use buttons in the Tools Shelf to reunify an object's origin with its geometric center:

1. With Blender in Object Mode, click  LMB  on Set Origin in the Tool Shelf (under the "Edit" sub menu of Tools) and select Origin To Geometry (Blender 2.70: "Object" -> "Transform" -> "Origin to Geometry") to move the selected object's origin to its geometric center (without changing the object's appearance).
 When more than one object is selected, Blender uses the average of their median points as the median point for pivoting.

This can be useful when you want a better picture of your object. With the origin set to the person's geometric center, you can now snap the object with  Shift+S  to the 3D cursor. This will let you view more of the model at one time and make for a faster editing workflow.

## Positioning the Hat

Positioning the hat

Once you have the hat properly oriented, move it into position on the person's head. The grab tool enables you to position objects in Object Mode in the same way you positioned vertices, edges, and faces in Edit Mode.

1. Make sure Blender is in Object Mode.
2. Click  RMB  on the hat object to select it.
3. Activate the grab tool by pressing  G .

As you move the mouse pointer, the hat will move around in the viewport. By default, the movement plane is perpendicular to the view axis, so the hat will move differently depending on which viewpoint you're working in.

Just as in the Edit Mode grab tool, you can:

• Restrict the direction of motion by pressing  X ,  Y , or  Z . Press once to move parallel to a global axis, twice to use a local axis. (Press the same key a third time to return to view-plane motion.)
• To restrict motion to the global X-Y plane, lock the global Z by pressing  Shift + Z .
• Hold down  Ctrl  to restrict motion to discrete steps (typically one Blender unit).
• Hold down  Shift  to get finer control over the motion.
• Click  LMB  or press  Enter  to finalize the position and exit the tool.
• Click  RMB  or press  Esc  to return the object to its previous position and exit.

Use two different orthographic views to position the hat on the person's head. You will probably want to scale the hat to make it fit the person's head better. When you are doing this along the X or Y axis, make the changes symmetrical by specifying the axes you want scaling to be constrained to. This option is available in the Operator panel (just below the Tool Shelf) and also by pressing F6.

## Parenting the Hat to the Person

Once you have the hat properly sized and positioned on the person's head, you'll want it to stay there. In order to maintain such a cozy relationship between two objects, you'd have to remember to select them both before rotating, moving, or scaling. A drastic solution might be to join them into a single object using  Ctrl + J .

A better compromise is to Parent the hat to the person. Parenting creates a relationship between two objects, such that certain changes to one object (called the Parent object) automatically affect the other (called the Child object). Changes to the child, however, do not affect the parent.

Note that an object can have many children, but only one parent.

Since the person is bigger than the hat, it's logical to parent the hat to the person (meaning: parent = person, child = hat) instead of vice versa.

1. Make sure Blender is in Object Mode.
2. Click  RMB  on the hat object to select it.
3. Click  Shift + RMB  on the person object.
Both the person and the hat should now be selected. The order of selection is important here.
4. Press  Ctrl + P  to parent the hat to the person.
5. Select Object. The most recently selected object becomes the parent of all other selected objects.
 Pressing  P  in the object mode instead of  Ctrl + P  will start the Blender game engine. To stop the game engine, press  Esc .

Now when you move the hat you will see a line from the hat to the person, indicating that the person is the hat's parent. And if you move the person, the hat will move with it.

You may get an error saying something like Loop to Parents, fix this by clearing all previous parents with  Alt + P .

## Renaming Objects

The renaming dialog

When you have multiple objects in a scene, it helps to give each one a name.

Click on the Objects tab in the Properties panel (the one with a box icon).

1. Now select the hat by clicking  RMB  on it.
2. At the very top of the tab you should see a dialog box with the name of your object
• The hat's name might be something like "Circle" depending on which mesh primitive you first built the hat from.
3. Click  LMB  on the dialog box and type in a more descriptive name like "Hat".

You have now changed the name of the hat's object datablock. This name change will be reflected in the Outliner, which we will look at shortly.

Now select your person by clicking  RMB  on it and repeat the process, changing the name to something like "Person".

## Outliner Windows

The Outliner window.

Once you give objects names, it helps to have a way to find objects by their name and parent. This is exactly what the Outliner is for and it comes in very handy when you are working with a large scene. The Outliner is usually just above the Properties panel. You may want to pull it down a bit to see it more clearly.

You'll notice that all the objects in your scene (Person, camera etc) are listed and that you can select these objects by clicking  LMB  on them. And if you click  RMB  on an object, a menu will pop up with options like Select, Deselect, Delete etc. If you select the Person and then click the "+" sign to its left, you will see that the Hat is listed below the person. This is because Blender lists all children objects beneath their parents.

On the right of each object there are a series of icons which represent the state of the object. For example, the eye icon means that your object is visible in the 3D viewport. You can turn off its visibility by clicking  LMB  on the eye, which will turn grey; click again on the eye to make it visible. If you hover the mouse over the icons a text box will pop up with a description of what that particular icon does.

## Good on ya' mate!

Congratulations!! You have now finished your simple character. Pat yourself on the back, and have a celebratory coffee! (Or pop!)

# Overview

Blender 3D: Noob to Pro/Materials and Textures/

# Quickie Material

In this module, you will create a new material called "Green Ooze". Along the way, you will learn how to alter the diffuse, specular, and mirror colors of a material.

Figure 1: The Materials context in the Properties window.

The cube in the default scene (which you get from File → Load Factory Settings) has a simple grey color. Now click on the Materials context in the Properties window.

The materials context contains various menus, but for now you only need diffuse, specular and mirror. The material is named and linked in the panel above the preview window. (Linking is a feature that allows materials to be shared between multiple objects (or datablocks). Changing a material affects the appearance of everything it is linked to.)

The first row of the window above the preview window indicates that:

• there is one material assigned to this object and its name is "Material".

The second row of controls indicates that:

• The current selected material's name is "Material".
• This material will only be saved if it's in use.
• It is not a "Nodes" material.
• Instead of being linked directly to an object, the current material is linked to a datablock.

To rename the material, click  LMB  on the name and enter the name you want.

To unlink the material, click  LMB  on the X button to the right of the material name ("Material"). Do this now. This deletes the link to the datablock, removing the material from the mesh. As a side-effect, most of the panels in the Material context disappear. You will see in a moment, however, that the material still exists. It hasn't been deleted; it is simply no longer in use.

At this point, you could click  LMB  the "New" button to create a new material, but instead we are going to reapply the old material:

1. Click  LMB  on the button to the left of the "New" button.
2. You'll see a nifty drop-down list containing all materials you've created so far. Choose 0 Material.

Materials whose names are preceded by "0" in this list are not in use. By default, Blender doesn't save such materials when it saves the scene. Thus, you can delete a material from the list by saving the scene and then reopening it. You can override this behavior by toggling the "F" button "on" for unused materials you want saved.

Your materials will be much easier to find and manage if you give them brief, descriptive names you can recognize at a glance. Change this one's name to "Green Ooze". In addition, naming of your materials and other objects in your scene is useful when such components of your scene will be appended in another scene of a different Blender file. Naming your materials and other stuff in the scene will enable you to choose the right objects and materials you need whenever you wish to append just a portion of a whole bunch of work you did. For instance, you're working on a new Blender project, but felt the material you used in this Blender file is worth it. Instead of going through the pain of creating a new material (of course you guessed in the initial one in getting the right material appearance), you just append the material to your new work. Pretty simple! Make naming a habit, as it's much used in a production environment.

## Specifying Colors

Simple materials are specified by three colors: diffuse, specular and mirror. Rectangular patches (swatches) of the colour in their own panel in the Material context allow you to see and change each of these. Diffuse color is the basic underlying color of the material, rendered by the diffuse shader. Specular color is for highlights (small bright spots on a shiny surface) as rendered by the specular shader. Mirror color is for true reflections rendered using ray-tracing.

There are many ways to define colours. Blender supports three:

• RGB: By specifying relative amounts of red, green and blue primary colours, by giving a number from 0.0 to 1.0 for each component. For example, (R, G, B) = (0, 0, 0) specifies black (no colour at all); (0, 1, 0) is full green; (1, 1, 0) (full red + full green) is yellow; (0.5, 0.5, 0.5) is 50% grey, and (1, 1, 1) is full white (maximum intensity of all components). Note that this is additive mixing of colours, which is what happens when you shine lights of different colours onto a white screen, not the subtractive mixing that takes place when you mix different-coloured paints or inks on paper or canvas.
• HSV: By specifying a hue (colour position on the rainbow) together with a saturation (strength of colour, from garish down to pastel, with zero giving shades of grey) and value (brightness). This is generally considered to be easier to use than RGB notation when you are trying to create new colours (as opposed to copying a colour spec from somewhere else), since it is easier to predict what the likely result will be. HSV is commonly represented on a colour wheel, where the hue is the angle around the circle, saturation the distance from the centre, and value controlled by a separate brightness slider (as shown below).
• By specifying a 6-digit hexadecimal number. This is just an alternative form of RGB notation, commonly used for colour specifications in Web pages.
Figure 2: Blender’s colour picker popup

If you click on any colour swatch, the colour picker will pop up, allowing you to change the values. This is the most intuitive way. The window that appears will look like this and will include the following (Figure 2):

1. A color wheel to change the color as you want. In HSV mode, H corresponds to angle around this wheel, while S corresponds to distance from the centre.
2. Three color sliders that will change if you change the color in the colorwheel. You can also change the values with the sliders.
3. A slider that controls the intensity of the color. This corresponds to the V in HSV.
4. A pipette capable of sampling colors from any Blender window or render window.
5. Buttons that can change it to "HSV" or "HEX" mode.
• Alternatively you can specify hue, saturation and value components by clicking  LMB  on the "HSV" button and pushing the sliders around accordingly.
• You can also press the last button and enter the hexadecimal (or HEX) code. This is simply a different representation for RGB, where the hex digits represent rrggbb.

HSV is probably the most easily understandable way of specifying and experimenting with colours. However, as is common with most computer systems, all colours in Blender are represented internally as RGB.

If you want to get rid of the window just click  LMB  anywhere else.

 Duplicate intensity sliders? There are two ways to control the intensity of the colour: there is the vertical intensity slider at the right of the colour picker popup, and there are also the intensity fields at the bottom of the Diffuse and Specular panels (above), the final intensity being the combination of both values. Why two different ways? Partly this is to allow a quick way to moderate or intensify the diffuse or specular components, without having to change the actual colour specification. But more importantly, this is to ensure that intensities are never set to 100%. The reason is that this can cause rendering calculation problems, leading to total light intensities accumulating to infinity instead of converging to a finite value. This is probably not a big issue with the Blender Internal renderer, but can become a problem with more advanced renderers.

The most used method of creating a color of your own is using the color wheel, but because we want to be sure you will get the exact same color as us we will use the sliders. Use the above methods to set the diffuse color to R=0.149, G=1.000, B=0.446 (or use the HEX code: 6CFFB2). If you look in the "Preview" panel, you will see that the material is now bright green.

Most real-life materials (other than metals) don't alter the color of specular light. For this reason, Specular and Mirror are usually left at their default values (white). For green ooze, however, you'll disregard this rule-of-thumb:

1. Click  LMB  the sample rectangle below the Specular window.
2. Use the color selection dialog to adjust the specular color and watch the Preview panel to see how this color affects the sample sphere's highlight.
3. Set the specular color to R=0.640, G=0.990, B=0.566 (or use the HEX code: D1FEC6).

With these values for Color and Specular, you should be able to get a good ooze later on. The Preview, Diffuse and Specular panel should now look like this:

As you can see, there are many other material buttons. Many of these will be explained in later modules. Suggestions for creating specific materials may be found in the "Every Material Known to Man" module.

Save this scene before proceeding. You will need it for the "Quickie Texture" module, in which you will perfect your ooze.

 Copying/Pasting Colours: Quite often, you will want to duplicate or move a colour specified in one place to another. If the two colour swatches are simultaneously visible, you can use the eyedropper button in the colour picker. But if they are not, then the easiest way is to bring up the colour picker for the colour you want to copy, switch to the hex display, select the 6 hex digits, and copy them with  CTRL + C . Then go to the colour you want to make the same, bring up its picker in hex mode, select the hex digits, and replace them with what you copied using  CTRL + V .

# Multiple Materials per Object

The finished render.

In this module, you'll create a beach ball with two alternating colours. Along the way, you'll learn how to apply multiple materials to a single object.

Many real-life objects have parts which are different colours, or are even made of different materials. One way to model such objects is to make each part a separate Blender object. However, Blender also allows you to assign different materials to parts of a single object.

## Set the Scene

Begin by opening Blender and removing the default cube. Then select the lamp and change its type from 'Point' to 'Hemi' in the Light settings in the properties window (object data button), this has the advantage of it giving more light.

The options for changing lamp type in the properties window

Now create a mesh for the beach ball:

1. With the 3D View window active, press  Shift + A ) and choose Add → Mesh → UV Sphere.
2. In the "Add UV Sphere" panel in the bottom of the tool shelf, specify 8 segments and 4 rings.
The initial result will be crude, but meshes with fewer vertices are easier to edit.

Make the mesh rounder and more organic using automatic subdivision:

1. In the "Properties" editor, select the "Modifiers" context (wrench icon).
2. Select "Add Modifier" and click Generate → Subdivision Surface.
3. For the number of subdivisions, set both the 'View' and 'Render' count to 2.

Get rid of that blocky look:

1. Ensure you're in Object Mode.
2. In the tool shelf, select the "Tools" tab.
3. In the "Edit" panel of that tab, set the shading to Smooth.

The ball is now round, but a bit prolate. To make it more spherical, scale it by about 1.1 along the X and Y axes. To select the X-Y plane, you select ′not Z′, by using the key combination  Shift + Z . The complete sequence is, then,  S ,  Shift + Z ,  1.1 .

## Colorize Time

1. Press  Tab  to put Blender into Edit mode.
2. In the Properties editor, select the "Material" button .
3. Press "+ New".
A new material appears in the material slot list, and several additional panels appear below to edit the created material.
4. In the "Diffuse" panel, click on the default white diffuse color and change it to a nice yellow.
At this point, the entire ball is yellow.

In the "Materials" panel click the "+" button (indicated by the red box in the picture, below) next to the material slot list to create a new blank slot. The "+ New" button will reappear (indicated by the blue box, in the picture below).

Click the "+ New" button and a new material will be created and assigned the empty slot in the materials slot list. Ensure that the new material is selected, then change the diffuse color to blue. Nothing will happen to the beach ball, yet.

Now make a single blue stripe on the ball:

1. All the vertices should still be selected from before; make sure the 3D view is active, then hit  A  to deselect them.
2. Switch to front view with  NUM1 , and to "Face Select" mode with  Ctrl + Tab  then  F .
3. To avoid accidents, make sure that the "Limit selection to visible" option is enabled in the 3D View header bar.
4. Select a column of four faces that will make up one stripe of the beach ball (using  SHIFT + RMB  on each face):
5. In the "Material" property window, select the blue material slot in the list, then click the "Assign" button.

Rotate the view (e.g.  NUM6 ) so you can skip past a yellow stripe adjacent to the blue stripe, and select the second column that will become a blue stripe. Work your way around the ball to do this two more times. (Remember we made the sphere with 8 segments; four of these are yellow, and four are blue).

Now you see the benefit of making a sphere with only 4 rings: more rings would have meant more faces in each stripe, and more clicking to select them.

# Metal Versus Plastic

There are different kinds of shiny materials. Consider the difference between a shiny metallic object, and one made out of a glossy nonmetallic material (like plastic or ceramic). This page will explain some simple techniques for (approximately) mimicking the appearances of these materials using shader settings in the Blender Internal renderer.

For all the following manipulations, start a new Blender document, get rid of the default cube, and replace it with a UV sphere. Set it to be smooth-shaded. Change the lamp falloff to be inverse linear, just to make the scene brighter. Assign the sphere a new default material. It is the settings of this material we will now proceed to play around with.

## Making It Plastic

For a plastic or glossy effect, give the material a diffuse colour, but leave the specular colour at white. Increase the specular intensity to something like 0.9.

(In this and the following examples, I used a diffuse colour of #E7398B.)

## Making It Metal

Now change the specular colour to be the same as the diffuse colour. (The easy way to do this is to bring up the specular colour picker, click on its eyedropper icon, and use the eyedropper tool to click on the swatch showing the diffuse colour.) Also lower the specular hardness from its default value of 50, to something like 25 or even 12. This will spread out the specular highlight, giving the impression of a surface that is shiny, but not perfectly smooth. Also lower the diffuse intensity, to something like 0.05.

To make the metal more convincing, you may want to choose a more typical metal colour, like grey, copper or bronze.

## Making It Ceramic

Let’s try for a glazed-ceramic look, or perhaps some dark, shiny stone like obsidian. Set the specular colour back to white (the easiest way to do this is to switch to HSV view in the colour picker and set the S(aturation) value to 0). Increase the hardness to something like 200 to narrow and intensify the specular highlight. Leave the specular intensity high and the diffuse intensity low.

To get an even more sharply-focused highlight, change the specular shader model from its “CookTorr” default to “WardIso”. The “Hardness” parameter gets replaced with a “Slope” instead; leave this at the default 0.1.

# Texture Settings

Material texture settings

In the Properties window, you will find the Texture context, which looks like at right.

At the top you will see a row of three icons , which indicate texture settings to view and change:

• World Texture — a texture to use for the sky backdrop
• Material Texture — a texture associated with the currently-selected material
• Brush Texture — a texture used for some other purpose.

There are two main types of textures in Blender:

• Image/Movie textures
• Procedural textures (all other types in the Type menu).

An image/movie texture allows a two-dimensional image (which might be static or moving) to be wrapped around the surface of a three-dimensional object in some way. Alternatively, a procedural texture directly maps a predefined three-dimensional mathematical function to the surface coordinates of the object.

The “Coordinates:” popup menu defines how positions on the object surface are mapped to positions within the texture coordinate space. All of these options specify automatic mapping algorithms, except one: the “UV” option. This one lets you work within the UV/Image Editor, where you unwrap the surface of the mesh onto a flat rectangle showing the texture image (this really only works with Image/Movie textures), and then move sections of the mesh around to make them show corresponding parts of the texture.

The “Projection:” popup menu further controls how the two-dimensional surface of the object is mapped to a two-dimensional Image/Movie texture. It seems to have no effect for procedural textures.

The “Offset:” and “Size:” X, Y and Z values allow simple adjustments of the position and scaling of the texture. Note that the size values work the opposite way to what you might expect: larger values here make the texture smaller along the corresponding dimension.

The image at right shows the common settings panels for all material texture types. Additional panels will appear depending on the chosen texture type; the settings shown are for the “None” texture, which is the same as having no texture at all.

## Material Textures

A material may have more than one texture associated with it. At the top of the material texture settings (see above), is a list of the texture slots associated with the material. Slots may be empty (unused), and slots containing a texture may be enabled or disabled, by checking or unchecking the box at the right of the list item. Disabling a texture slot stops it having an effect on the material, which is the same as deleting the texture from the slot altogether, except it is easier to revert. This can be useful when trying to debug the effect of a combination of textures on the material.

## World Textures

You previously saw how to set up colours for the sky in the World Settings; you can also add a sky texture as well.

World texture settings look similar to texture settings: again there are a number of slots, and there are mapping and influence options. But the mapping coordinates types are different (and there is no UV option), and the influence types are more limited.

 Note that the only Influence checkbox checked by default is “Blend”.

If you’re wondering why your texture definition here is making no difference to your sky, either make sure the “Blend” checkbox is checked in your World settings, or check the “Horizon” Influence box here if you don’t want a sky gradation.

# Image Textures

## Image Texture Settings

Simple checkerboard

To understand how the texture settings apply to image/movie textures, start with an example texture. A nice simple one is this checkerboard at right—don’t forget to download it in (or convert it to) PNG format, as Blender cannot use an SVG file as a texture.

Start a new Blender document. Note the default cube already has a a default grey material, called “Material”, and this already has a single texture, called “Tex”, of type “None”, which means it has no effect.

 Before proceeding, go to the World context and turn on Environment Lighting (you can leave its default energy at 1.0). This will ensure the cube is more evenly lit, for easier visibility of the texture effect.

Under the Texture context of the Properties window, with Material Texture selected, change the texture type to “Image or Movie”. You will immediately see some new panels pop up in the texture context. Look for the Image panel, as at right. This initially contains a popup menu icon for selecting from any previously-loaded images (this will start out empty), a “New” button for using one of Blender’s predefined test textures, and an “Open” button for loading an image from a file.

Click the “Open” button, and select your previously-downloaded or converted PNG version of the example checkerboard texture.

Now a whole lot more settings will become visible. From the top, the panels are:

• Preview — gives you a simple display of how the texture looks.
• Colors — lets you make simple adjustments to the image brightness, contrast etc.
• Image — lets you choose from any already-loaded images, and shows you the pathname of the file the image was loaded from. Note the two arrows in a circle to the right of the pathname display: clicking this will tell Blender to reload the image from the file, which is useful if you make changes to it in an external image editor.
• Image Sampling — controls how the image can be interpreted in a different way from straight pixel values.
• Image Mapping — lets you crop the input image, and apply fixed numbers of repetitions to it along each axis, even before it goes through the usual texture-tiling repetition process.
• Mapping, Influence — these are more general panels that apply to all types of textures. They will be discussed in more detail shortly.
 Image packing: the icon to the left of the image pathname lets you pack a complete copy of the image into the .blend file, so it no longer keeps reading the original image file. This can be useful if you want your .blend file to be self-contained, particularly if you want to send it to others. On the other hand, if your workflow depends on coordinating with someone else doing the image editing, it may be more convenient to leave it linking to a separate image file.

Projection: flat; axes: X→X, Y→Y, Z→Z

If you render  F12  now, you should end up with an image like this. Notice in the Projection menu (TextureMapping) the initial selection is “Flat”: this means that the texture X and Y coordinates go straight to object X and Y coordinates. Thus, the texture only appears on the top (and also bottom) of the cube, not on its sides. See also the three little popup menus just below the Projection menu, each containing the items X, Y and Z. These let you rearrange the object coordinates that the texture coordinates map to. If you change the first two, you can get the texture to appear on other pairs of sides of the cube, other than the top and bottom. The third menu (corresponding to the Z axis of the texture) has no effect (yet), because a flat image texture is only two-dimensional.

Texture size increased to 3.

Now try changing the three “Size” fields in the Mapping panel: give them all a value of 3. This will uniformly shrink the texture pattern to one-third of its original size. Or alternatively, it will require three times the number of texture repetitions to span the same distance as the original.

Texture projection set to Sphere

Now let’s try the other Projection types. Here’s what “Sphere” looks like. Imagine the texture pattern as a flat sheet stretched and curved around, and its edges joined to form a sphere surrounding the actual object; then the sphere is shrinkwrapped down onto the object.

Note the top and bottom edges of the sheet shrink down to single points at the north and south poles; this is why the squares of the checkerboard pattern turn into triangles next to these points.

 Z-axis now works: because these projection types other than “Flat” turn the texture into a 3-dimensional object, you can now use all 3 of the axis-rearrangement menus to reorient the texture in interesting, not to say confusing, ways. What happens when you assign the same texture axis to more than one object axis?

Texture projection set to Tube

Here’s a Tube mapping. Here the texture pattern sheet is rolled round into a cylinder, with only one pair of edges joined together, the top and bottom left open.

Texture projection set to Cube

And lastly, here is a Cube mapping. Here 6 copies of the texture pattern are arranged parallel to the faces of a cube, before being shrinkwrapped onto the actual object. Which in this case, happens to be a cube.

Cube mappings are very commonly used in game engines, because they are just about the simplest way to wrap a texture around an entire object.

“Mapping” versus “Image Mapping”

Procedural texturing is very powerful; however, sometimes it is difficult or impossible to generate the desired realism with them. Image texturing is there for you when you need it. To review, the basic idea is to take an outside image and wrap it around your model. You can use any texture, or a seamless one if you want it to repeat to get a tiled effect. The following shows how you create a seamless texture, and then how to apply any texture (seamless or otherwise) to an object.

### The difference between 'tiled' and 'seamless'

In many cases a simple material will just not cut it for an object, and you will want to apply a texture to it. However, depending on the object, you may want to apply either a seamless or tileable texture. A seamless texture is an image that will, when applied to an object, spread evenly across the surface of the object without any visible borders or 'seams' even if the object is many times larger than the resolution of the image (also called 'procedural textures' in Blender). These can be useful in many situations; such as when you want a texture for a carpet to seamlessly repeat itself without having a huge resolution.

A tileable texture on the other hand, is an image that will repeat itself across an object, but with noticeable seams. Any image can be used as a tileable texture, but often they will only be used in specific instances such as a vinyl floor with a tiled pattern on it.

See Using Textures for more details on applying images as textures, and using them to affect many other surface attributes such as luminosity, reflectivity, translucency, displacement etc.

### How to make a tileable texture with the GIMP

It is easy to create a tiling texture image with the GIMP. Start with the photo you want to use. Crop out any part you don’t want. Here’s an example random photo of some plants in my garden:

Go to Gimp’s “Filters” menu, and find the “Map” submenu. In here you will find the entry “Make Seamless”. Select it. That’s it:

Just to prove it works, here’s a (scaled-down) use of the result as a tiled fill pattern:

### Other Image Texture Editors

• Wood Workshop A free utility (Requires Operating System: Windows 2000/XP) that generates surprisingly high quality tiling wood texture images. These textures can be exported as standard image files for use within Blender.
• MapZone A free utility for Windows (works perfectly in Wine) that generates node based procedural texture maps. Mapzone can export diffuse, normal and alpha texture maps as standard image files. It can also import SVG regions created with Blender's UV mapping tools.

# Procedural Textures

Procedural Textures

Texturing objects can be broken down into two categories: procedural and image texturing. Procedural texturing makes use of mathematical formulas to generate textures. This is nice because it can be used to make relatively nice looking textures without external images which are very temperamental where you put them. Procedural Textures are all stored in the .blend file. These textures are obviously generated within Blender itself. Image texturing uses images created or captured outside of Blender, either from an image manipulation program such as the Paint.NET, GIMP or Photoshop, or captured on a camera. We have already learned about image texturing, so let's move on to procedural texturing.

Current Procedural Textures

Blender currently supports many procedural textures, including: Clouds, Marble, Stucci, Wood, Magic, Blend, Noise, Musgrave, Voronoi and DistortedNoise.

## A Simple Wood Texture

Let's define a simple wood texture:

• Start a new Blender document containing the default cube.
• Select the cube (and nothing else).
• In the Properties window, go to the World tab and turn on Environment Lighting (you can leave its default energy at 1.0).
• Go to the Materials tab , and rename the default "Material" to "Wood Material". Alternatively, delete the default material using the X to the right of the name field and add a new material.

Let's add some color and texture. You can see the results at any time by pressing F12 to re-render the scene.

Start by painting the cube a base color using the Wood Material's "diffuse" color:

• In the “Material” tab,
• Scroll down to the “Diffuse” properties panel and choose a darker brown color e.g. #A57E3F.

See http://en.wikipedia.org/wiki/HSL_and_HSV for where brown fits in the color wheel.

Next, let's add a texture to give the material some highlights.

• Switch to the “Texture” properties tab , and again rename the default "Tex" to "Wood Texture" or create a new texture. Notice at the very top of the "Texture" tab "Cube > Wood Material > Wood Texture"
• Change the Type of the material to “Wood” using the pop-up menu.

The texture sample will show parallel alternating black and white bars that don’t look very woody at all. Never fear! The black regions will be the material's base "diffuse" color. The white regions are like "highlights" that will be painted over the base.

Let's make some improvements to the texture:

• While still in the “Textures” tab,
• Scroll to the “Wood” properties panel that appears, change the waveform from “Sine” to “Saw”.
• In the next row of buttons down, change the type from the default “Bands” to “Ring Noise”.
• Increase the Noise Size to 1.0.

Now the texture sample should show something resembling wavy tree-rings. If you hit F12 to render now, you will see these rings covering your cube, except a) the colour is wrong, and b) normal wood patterns aren't so nearly circular.

To make the pattern more elongated:

• Scroll to the “Mapping” properties panel,
• Change the Size X value to 2.0 and Y to 0.4. This squishes the pattern down along the X-axis, and stretches it out along the Y-axis, giving the elliptical tree-ring shapes you commonly see on wood planks and boards.

Hit F12 to render again, and the shape of the texture should be looking a lot more woody now.

The final step is to color the highlights in the texture:

• In the “Textures” tab,
• Scroll to the “Influence” properties panel further down,
• Click on the color swatch, and choose a nice brown colour.

For a nicer effect, I chose a very light brown e.g. #DEB887.

The result should look very woody indeed!

• Remember that you need to Render to see the wood grain on your object.

# Quickie Texture

Textures are laid on top of materials to give them complicated colors and other effects. An object is covered with a material, which might contain several textures: An image texture of stone, a texture to make the stone look bumpy, and a texture to make the stone deform in different ways.

A texture may be an image orTemplate:LCMS a computed function. What the texture does and how it is mapped onto your object is set in the material buttons. Some commonly used texture types are shown on the page Using Textures.

This tutorial uses the file from the Quickie Material tutorial. If you didn't do it before, go back and do it now.

## Making It Mottled

Texture Context with all the relevant panels.
##### Step 1: Adding Texture to the Material
• In a Properties window, switch to Texture context.
• A default texture, Tex, should already be available and set to Type: None.
• If not, click one of the Texture Slots (the ones with chequered icons) and click the New button.
• Set the Type to Clouds.
• The Texture Preview panel will now reflect this change. However, said change will not be reflected in the 3D view window.
• You can do a quick render (F12) to see the change. However, you'll have to re-render every time you change a setting to see its effect.
• Otherwise you can click the Material button in the Texture Preview panel to see the changes to the material. (Click Both to see them side-by-side.)
• A better, albeit more resource intensive option would be to change the Display Mode to Rendered. (Shift+Z in the 3D view window or Selecting the Display mode from the 3D view Header.
##### Step 2: Refining the Texture
• Once you use one of the ways to preview your work, you'll see Green and Magenta mixed in resembling a polished granite texture.
• This is the default colour for any generated texture. Now all you have to do is change it to black.
• But before that scroll down to the Mapping panel and make sure that Coordinates is set to Generated, Global or Object (for best results).
• Scroll down to the Influence panel, and click on the colour swatch and drag the reticule in the bar to the right all the way down.
• Now the texture should look more or less like green granite
Render result in 3D view.

## Making It Bumpy

##### Step 1: Adding a second Texture to the Material
• In a Properties window, switch to Texture context.
• The Cloud texture you just created will be listed in a slot.
• To create an additional texture click a second texture slot and then click New button.
• Change the texture Type to Stucci.
• Now if you preview this texture you'll only notice a bit of magenta mixed in with the previous texture.
##### Step 2: Making the texture a Bump-Map
• Scroll down to the Mapping panel and make sure the Coordinates is set to Generated, Global or Object for best results.
• Scroll down to Influence panel uncheck Color and check Normal under Geometry, then set it to 4.
• If required, set the Method under Bump Mapping to a higher Quality.

The render result should look like the one on the right.

Now mess around with the various settings we discussed, Particularly the settings in Clouds/Stucci, Mapping and Influence panels. Also try the whole tutorial (Quickie Material & Quickie Texture) with a sphere and other shapes.

## Some Closing words

The downside of bump-mapping, as you may have noticed, is that it only provides an illusion of depth/bumpiness. The edges will still be straight as in the render. For curved surfaces the outline will still look spotless while the centre looks deformed, plus shadows will still render smooth compromising the illusion. An alternative technique is displacement-mapping which actually deforms the mesh as per a texture to produce depth in the mesh, with the downside of creating a higher poly mesh.

With bump-mapping in general, you will get a greater effect on smoothly curved surfaces with high specularity as compared to flat surfaces with low specularity.

# Halo Materials

## Introduction

Halos are a neat effect. Instead of giving a colour/texture to the faces of a mesh, like normal Surface materials do, the Halo material ignores the faces and renders representations of the vertices instead. This can produce all kinds of ethereal, even ghostly, fantasy effects, of objects that look like they’re made out of light rather than ordinary solid matter.

A halo material can also produce a flare effect. This is the “lens flare” that happens when a physical camera is aimed at a very bright light source; the spillage of light bouncing around inside the optics produces coloured rings and other interesting artifacts on top of the image. This has become such an accepted part of photography that computer graphics programs like Blender, which do not suffer the imperfections of physical lenses, go to a great deal of trouble to offer a realistic flare effect.

Flare effects can also be achieved using compositing node and a material with an "emit" value, such flares may in some circumstances render faster and be simpler to control. This works for the Blender internal render engine, as do flares generated with halos. This is done by opening the node editor (switching the 3d viewer tab to one of these for example) then clicking "compositing nodes" and "use nodes", "filters" can then be added to produce these effects.

This tutorial will show you how to create an image representing a flare effect in a picture of the Sun.

## Setting The Scene

Open a new default Blender document. Get rid of the default cube. Insert a new UV Sphere mesh in its place, and set the number of segments and rings to 24 each. Also set Smooth shading. This will be your Sun. Create a new material for it, set the Diffuse colour to a suitable yellow. Under the Shading panel in the material settings, look for the “Emit:” slider and give it a value of 1.0 to make it look bright. Since the Sun emits its own light, you don’t need the separate default light, so get rid of that.

Go to the World properties tab . In the “World” sub-header, click on the colour swatch labelled “Horizon Color” and assign a nice deep blue colour for your sky.

If you do a render now, you should see your bright yellow orb, but without any flare effect.

Now add a new Circle mesh; the default 32 vertices should be enough. By default it lies in the X-Y plane, which again is fine. Move it along the Y-axis a little closer to the camera (negative-Y direction), until it lies outside your Sun sphere, but still close to it. Scale its size down by 0.5. (It will probably be invisible when first created, because it is initially inside your Sun sphere, but it will be initially selected, so you can immediately press  G   Y  and start moving the mouse without pressing any buttons, and make it appear from inside the Sun). Create a new material for it, and set the type to Halo.

In the Halo panel in the Material settings, increase the size to 3.0—this is the size of the fuzzy image that is rendered around each vertex, and this value is sufficient for them all to run together into a continuous ring. Reduce the Alpha to 0.05 to avoid overpowering the image with the halo effect.

Go further down the halo Material settings, and find the Flare panel (in Blender 2.75 you can check "Flare" but what settings you do, nothing will work). Check the title box to enable this. Set the number of Subflares to, say, 8 (this controls the number of separate halo reflections that will be generated, though you probably won’t be able to distinguish that many). Set the Boost to 10 to make the subhalos brighter than the original parent halo.

The Seed value in the Flare panel controls the particular flare pattern that you see; each number produces a different effect. I chose the value 3 for this example.

Where did the circle go? Like any object with a halo material, the circle object can be quite hard to see when it’s not selected. If you lose track of it, there are a couple of ways to find it again:

• Select everything with  A . Now you can look for the ring of dots and  RMB  on it to select it exclusively.
• Use the outliner window at the upper right. You should see it listed here under its default name of “Circle”; click with  LMB  to select it, and you should see the ring of dots appear in the 3D view.

If the circle object is still inside the Sun, then wireframe  Z  or bounding-box view modes may be helpful to find it again.

## The Final Result

Now hit  F12  to render, and you should see something like this (the flare effect may not appear immediately with the rest of the image, give it a few more seconds to appear):

Exercises: Try different positions for the circle mesh; move it near to the Sun (even partly in it), far from it, move it around to different sides. How does this affect the flare pattern? Also try changing the size of the circle mesh.

# Blender Memory Management

 This section may be a bit bewildering on first reading. If you don’t understand it right away, don’t worry too much; but as you work more and more with Blender, making copies of objects, or sharing settings between objects, feel free to come back and re-read this and hopefully it will make some subtleties of Blender’s behaviour clearer.

## Datablocks And Users

It is helpful to understand how Blender manages memory. Just about everything in a Blender document—objects in scenes, scenes themselves, materials, textures, whatever—is stored in a datablock. Each datablock has a name, which must be unique among datablocks of the same type. Each datablock may be referenced from one or more places, mostly in other datablocks—in Blender parlance, it has one or more users. For example, several different objects might share the same material, so when you change the characteristics of the material, it automatically changes the appearance of all those objects.

If the number of users of a datablock drops to zero, it still stays around in memory, but it will not be saved when the document is saved. Thus, if you save and reload the document, all the datablocks with zero users will disappear. (In some cases you may need to save and reload a couple of times before all zero-user datablocks disappear.)

But up until that point, the datablock will continue to appear in the relevant popup menus, so you can reassign it to more users.

You can also assign a fake user to a datablock; this is what the “F” button is for in the popup menus that list datablocks of that type. This ensures that the user count never goes to zero, so the datablock always gets saved in the document even if it has no real users. This is useful for “library” documents, which can contain collections of useful materials and textures, say, that can be linked or imported into other documents, without also having to include dummy objects in the library just to ensure those materials and textures get saved.

For example, here is the widget that lets you choose the material for an object:

The main part shows the name of the current material, which is editable. The X button breaks the link to this material and decrements its number of users by one, while the F button assigns a fake user to this material. The + button lets you create a new material.

The material symbol on the left pops up a list of existing materials to choose from, plus a search box to search all existing materials:

Note the entry with the 0 symbol next to it; that currently has a user count of zero, and will disappear when the document is saved and reloaded, if it is not further used.

The widget also displays the current user count if it is greater than 1:

In this case the count was incremented because the F button was selected.

 Clicking the number (if it’s greater than 1) makes a copy of the Material, attached only to this particular user. The copy has a user count of 1, while the original has its user count decremented by 1.

This is the basis of the (slightly confusing) distinction in Blender between object datablocks and object data datablocks. Object datablocks contain the information common to all the types of objects in the 3D scene, regardless of whether they’re mesh objects, lamp objects, camera objects or whatever; whereas the object data datablocks contain the information specific to that instance of the type of object, e.g. the vertex, edge and face definitions for this particular mesh you might be using, or the colour and energy of a lamp you've set up for your project, or the field of view of a camera you have.

Which leads us to the difference between the two object duplication commands,  SHIFT + D  and  ALT + D : the former duplicates both the object datablocks and the object data datablocks (though this can be controlled in your User Preferences), while the latter only duplicates the object datablock. What that means is that in the first case the two objects are truly independent, but in the second case the new object continues to share the same object data datablock so a change in one will result in a change in both of them. So, for instance, if you use  ALT + D  on a mesh object and edit the vertices, edges or faces on one copy, the other copy will also be affected.

# A Common Pitfall in Older Tutorials (Align to View Issue)

For fast reference, Just Click after every new created mesh on "align to view" in the tool shelf.

After much struggling to follow many tutorials based on older versions of Blender, I have downloaded multiple versions to discover why the tutorials based on versions such as 2.43 don't work when attempted on updated versions such as Blender 2.48a and above. Newer versions such as 2.48 have added a new option to /not/ have added objects rotated to the current viewpoint. With older versions, being in top, front or side view would cause any newly added objects to face different directions on creation.

The location of the button to make the circle show up in the correct orientation

Newer versions of Blender introduced the ability to force all objects into the same global orientation; even worse, they set it up that way BY DEFAULT! This means that unless the user deliberately changes the settings in the new versions, many older tutorials will act as if they are broken.

Newer versions of Blender (such as version 2.48, or 2.49b ) can be set to act in the same way as the older versions, by setting the Align to view on the (i): USER PREFERENCES menu in the right way.

Making this simple changes will "unbreak" tutorials written under Blender version 2.43, by allowing new objects to be automatically oriented to whatever viewscreen orientation is selected in the active viewscreen.

Any time object rotations, lattices or whatever else end up completely out of alignment with what older tutorials say should happen, these steps are your first best fix for almost every such situation.

In 2.58 and 2.61

The settings mentioned above are found in "File->User Preferences" (shortcut: Ctrl+Alt+U) under the "Editing" tab. There's a drop-down called "Align To" where you can set "View" or "World".

Noob Note: What actually happens by default on newer versions of Blender is that the axis of rotation is perpendicular to the screen. It means that, instead of revolving around the vertical axis, the object will revolve in the plane of the screen. Another way to deal with this is to change the view just before performing the rotation (I used NUM1 view) and come back to NUM7 once done.

Noob Note: In version, 2.63 for Linux, after changing "Align To" to "View", when adding through "Add" menu, the mesh will still be aligned to "World". To get it aligned to "View" You have to add it with SHIFT-A.

Align to view

Noob Note: In version 2.68a (unknown for older versions) there is a option to Align newly created mesh individually. When you create a mesh, (for ex. cylinder) there is a panel beneath the toolbox panel(left side of the 3D view) that shows up: Add "Mesh Name" (ex. Cylinder). Scroll down a bit and you'll see a check-box to enable "align to view". Checking it will align the mesh you added to the current view. Re-checking it after rotating the view around will align the mesh to new view.

# Using Bones

Blender 3D: Noob to Pro/Bones/

# Mountains out of Molehills

Now that we've created our simple person, it's time to give him somewhere to go. In this tutorial we'll create a mountain range using a few simple, and handy tools.

## Creating a simple plane

First we need a clean area to work with.

• Start off with a new project, using File → New, or hit  Ctrl + N . If you have a default cube or plane just delete them now (select them with  RMB  and press  X ).

Our first step is to create a large grid plane that we'll use for the ground and grow our mountains out of.

• Press NUM7  to enter top view. This way our grid plane will be lying flat when we create it.
• Press  Shift + C . This sets the 3D cursor to (0,0,0) which will be the center of the grid we will add (or use -  Shift + S Cursor to Center).
• Now add the grid with  Shift + A MeshGrid. This will be our canvas.
• Now add more vertices to the grid. In the bottom of the toolbox window, change the number of X and Y subdivisions somewhere from 15 to 20.
• Change to Edit Mode using  Tab
• Scale the grid plane up by about 15
First put the mouse close to the center of the grid plane and press  S  and drag the cursor away and watch the numbers in the bottom left of the 3D View. Hold  Ctrl  while dragging to increment by 0.1 for a more precise measurement. Alternatively, to enter the exact amount yourself, press  S , then simply type 15 and hit  Enter .

## First mountain

Now that we have the ground, it's time to start growing our mountains.

• Make sure you have nothing selected  A .
• Select a random vertex with  RMB . I usually start at the one that is 4 down from the top and 4 in from the left (the 4th vertex if you count the edges).
• Change to the side view with  Num3 .
• Press  O  to change to proportional edit mode or use the button which shows a grey ring on the header of the 3D View. The button will change its color to blue. You can also use  Space Transform→Proportional Edit (By default this button is located just below the 3D view).
• Once you've turned proportional edit mode on, another button appears to its right, the falloff button. Select Smooth Falloff here. Alternatively you can use the menu on the header of the 3D View (Mesh → Proportional Falloff → Smooth) or, using  Shift + O  will cycle through all of the different falloff types while using the Proportional editing tool.
• Press  G  to grab the vertex. We should now have a circle surrounding the vertex, this is our radius of influence. Basically any vertices inside this circle will be affected by any changes to the vertex itself.

Noob Note: If you're having trouble seeing or changing the radius of influence, try saving your scene and restarting Blender.

• Use  SCROLL  or  PgUp  and  PgDown  to adjust the radius of influence to include just over 2 vertices on each side of our selected vertex. (Depending on your version of Blender, you may need to use  LMB + SCROLL  to adjust the radius of the influence. On Mac, use  Fn + PgUp  and  Fn + PgDown ).
• Move the vertex up about 8 units on the Z-Axis. Do this by dragging the cursor up a little, and press the  MMB ; this should restrain the movements along the Z-axis. Now use  Ctrl  to move it precisely. Alternatively you can use  Z  to restrain movements to the Z-Axis, type  8  and hit  Enter . In older versions of Blender you may need to hit  N  before typing  8 .

Congratulations, we just created our first mountain. Now it's time to see what other things we can accomplish with the proportional editing tool.

## Peaks vs. hills

The 2.37 and onward releases offer at least 6 types and 2 modes of proportional editing. The previous release only has 2 of these types: Smooth and Sharp Falloff. We'll take a look at the difference between these two now.

• Change to top view again with  Num7 . You'll notice that now your "mountain" looks like a few differently shaded squares in the grid; you're looking down on shaded tiles, but in the Z axis, they're all still perfectly aligned with the original grid.
• Select another vertex away from the first. Let's say 4 from the bottom 4 from the right (counting the vertices on the edges).
• Change back to the side view with  Num3
• Select Sharp Falloff from the menu on the bar of the 3D View. Alternatively, using  Shift + O  will switch from one to the next of the 6 proportional editing modes while using the Proportional editing tool.
• As before, move the vertex up 8 units on the Z-Axis (Note: The radius of influence will still be the same size as when we last used it).
•  G
•  Z
• Type  Num8  and hit  Enter

Now we can see the differences between the sharp and smooth falloff. The same number of vertices are affected in both cases; only the degree to which they are affected is different.

The different proportional editing modes can be selected from the box immediately to the left of the proportional editing type box. The mode box contains four options: Disabled, Enabled, Connected, and Projected (2D). "Disabled" means that proportional editing will not be used. "Connected" means that only vertices linked to the selected vertices will be affected by the radius of influence. "Enabled" means that all vertices will be affected.

## Shaping the world

Now that we've created a couple of Mountains, it's time to see how we can use proportional editing to shape them.

• First make sure we're in side view ( Num3 ).
• Then on the smooth falloff mountain, the first one we created, select the vertex that is immediately down and left from the topmost point.
• Press  R  to rotate, scroll the  MMB  to change effective radius so it includes other points. Your screen should look like the photo to the right.

You can see the size of the proportional editing circle, and that there is only one vertex on the mountainside selected.

• Next hold  Ctrl  and rotate everything by -90. Alternatively, use  R ,  N , and type -90 and press  Enter . Your mountain should now look like this:

Noob note: be careful about the range of affected vertices. If the range is too small, then rotating will affect just the selected vertex. If the range is too large, it will rotate everything together. You can adjust the range by using  SCROLL .

Notice that the vertex itself did not move; since it is at the center of the circle it had no effect. The adjoining vertices within the edit circle were rotated around it in decreasing amounts the further from the center they are. Try doing it again with a larger proportional editing circle. Feel free to play around with scaling or rotating from different view points (don't forget that you can also use  G  to move vertices vertically or horizontally).

Try viewing your world from top view while rotating with a large effective radius. You will see the nearby vertices move close to the full amount while vertices further away move less.

## Smoothing things out

Now that we have a couple of budding mountains, you probably think they look kind of choppy. Sure they would be good if we were making an 8-bit console game, but we're working with 3D here, we want things to look sharper (or maybe smoother) than that. There are a couple of approaches to this. The first is to use more vertices when we create our plane. And I won't lie, it works. But it's also a HUGE resource hog. It would take your home computer hours of work just to keep things updated, let alone run it. So instead, we fake it. The easiest way to do this is to turn on SubSurfaces (we saw this in Detailing Your Simple Person 1.) For our purposes, let's set the subdivision (Levels) to 2. Also, ensure our SubSurf algorithm is set to Catmull-Clark (this is the default setting).

Now, you'll notice that with SubSurf on, we lose a lot of hard edges that we had, essentially we have no sharp corners any more. I don't know about you, but to me that doesn't make for a very interesting mountain range. So to restore our corners, we are going to use Weighted Creases for Subsurfs.

• First turn off proportional editing with  O  , and ensure we're in side view with  Num3
• Next, while still in edit mode, change to Edge Select mode with  Ctrl + Tab  and select Edges. Alternatively press Edge Select Mode button at the bottom of the object window.
• In the Tool Shelf at left, select the Options tab, then under Edge Select Mode, choose Tag Crease.
• On our Sharp Falloff mountain, the second one we did, select the two edges on the right. (see image below)
• Press  Shift + E  or  Space Edit → Edges → Crease SubSurf, then move the mouse away from the edge until the edge Crease reads 1.000 in the 3D viewport header. If moving the cursor there seems to be impossible, just hit 1 and enter.

As you move the cursor away from the edge you will notice two things. The first is that the edge becomes thicker as we move from it; this is showing how much of a crease we have (with Draw Creases turned on). The second is that you will notice the subsurfed mesh moving closer to the edge as the sharpness increases.

## Naturalness

Press  Ctrl + Tab  to enter Edit Mode and select vertices. Then go into front view  Num1 . Select the second vertex from the top in the centre of our Sharp Falloff mountain, then go into side view  Num3 . Hold  G  and drag the vertex inwards, not too far or your mountain will come out of itself on the other side. Just bring it in enough to make a small indent.

Then grab the top vertex and pull it down a small amount. You will notice that there is a small "crunch" in your mountain.

Don't forget to select all with  A , then  W  Shade Smooth button to smooth everything out.

OK, so your mountains are starting to shape up. But they still look a bit too neat. You could spend time moving each individual vertex but the chances are your model will still lack the natural feel. What we need is some chaos. Thankfully this is quite easy to accomplish. Firstly select the vertices that make up your mountains, all of them and a few around the base (box and circle select will make this easier). Select a few vertices between the mountains too. Next we use something called fractals. Fractals are chaotically (i.e. randomly) generated variables. In short you can use these variables to give your mountains a "wobbly" look.

Fractal option in 2.72

In the Tools tab of the Tool Shelf, press Subdivide (under Mesh Tools), then look at the Subdivide submenu below. The value in the Fractal box is the strength of the fractal. 1 is very low and will barely change your model. 10 is very high and will twist your models into very odd shapes indeed. Have a play with different values until you find one that you like. Around about 4.0 should do it. Hit OK and presto, your mountains have been transformed from clinical neatness, to lumpy chaos.

• If you make too many fractals, your computer will slow down. However, the more you add, the more bumpy and realistic it looks!

Repeatedly using the fractal tool seems to rapidly multiply the amount of vertices on your canvas. I suggest using the tool once, and if the result isn't satisfying, undo the result ( Ctrl + Z ) and try it again with a different fractal strength. Helpfully, even after undo, your selected vertices remain selected.

Now go back into Object mode and view the result.

# Modeling a Volcano

In this module, you will create a volcano using the proportional edit fall-off tool. You should be comfortable with deleting and adding meshes.

Delete the basic cube. Add a plane, and  S cale it up by 10. Rotate it so you see it in top-view (make sure it's in Orthographic view too).

Enter Edit mode and subdivide (with  W ) 5 or 6 times. More subdividing will give you a "smoother" volcano, but it also needs more CPU power.

The difference between "Subdivide" and "Subdivide Multi"...

"Subdivide" divides every square in the plane into four new squares. So every time you press "Subdivide" you will have four times as many squares as before. "Subidivide Multi" will make x horizontal and x vertical lines through your existing squares, so the new number of squares is: (squares_old)*(x+1)2, where x is the number you enter.

## Making the Mountain

In top view, select one of the points in the middle of the plane. With this point selected change to side view. Press the  O , which enables the "Proportional Edit Falloff" tool in the Menu-Panel beneath the 3-D-Window. As seen in the previous tutorial Blender 3D: Noob to Pro/Mountains Out Of Molehills when you move a vertex while edit falloff is enabled, all vertices in a defined radius of the selected vertex will align with the selected vertex when its position is altered. How they are adjusted can be chosen in the tab on the right of the yellow dot. I propose using "smooth falloff".

Now grab the vertex with  G . You will now see a gray circle. You can change its size with the mouse wheel. Every vertex inside this radius will be affected by the falloff. Change the size of the circle so almost the whole plane is in it.

Now move the vertex a bit upwards, as seen in the picture. Optionally you can lock the z-axis to make the volcano go straight up by pressing  Z .

As you can see all the other vertices will shift upward. We could keep moving this vertex at the same rate, but that would cause the plane itself to rise and bend, and that's not very good. So press  LMB  to apply the changes, grab the same vertex a second time and repeat the previous exercise as before, except now choose a smaller radius for the circle, about half the diameter of the plane ( G  Z  → scroll  MMB ).

Repeat this two or three more times and you will get something like this:

## Forming the Crater

Now we're going to create the "hole" on the volcano. First change the falloff to "root". Grab the vertex one more time, change the size of the circle so it's more or less as seen in the picture.

Grab this vertex down a bit, apply, grab it one more time with a smaller circle. You now should have something like this:

Just leave the border jagged and just smooth (Subdivision Surface) the whole volcano cause it is much more realistic. Go to Object mode, select the volcano, go to the "Modifier" menu in the "Properties" Header and just click on "Add Modifier" -> Subdivision surface (you can leave "view" on 1). Do not apply these settings yet.

First we'll do a test-render. Still in "Object mode" Delete the default Lamp point with "X" or "Delete" and place your 3D cursor behind the camera and press  Shift + A  -> "Lamp" -> "Point". With the Lamp Point still selected Click on The Lamp point Properties ("Data") in the "Properties" Header then change "Energy" to "10". Press F12 to enter Render, after adjusting the camera.

## Finishing the crater

You can very easily make a nice looking crater. Just go into "Edit Mode", touch "Num1". Make sure "limit selection to visible" is off and "proportional editing" is on and set it to "sharp" falloff. Select about the upper vertices with "border select" (Press "B key").

After that, scale (press "S key") it 'till it's a nice crater with a circle as large as mine.

And that's it, you just created a nicer looking crater.

Let's add some "magma" using lighting.

1. Make sure you're in "Object Mode"
2. Press  Shift + S  and choose Cursor to Center.
3. Press  Shift + A  and choose Lamp → Point.
4. In the Properties window, click the Data tab.
5. In the colour box (white by default) in the Lamp section, change the color to reddish-orange. (Red: 1, Green: 0.1, Blue: 0)
6. Set the Energy to around 7.
7. Raise the light until it's just above the bottom of the crater ( G rab along the  Z  axis).
8. If the ground level of your plane is reflecting light from the lava lamp this is because the bottom of your crater is above ground level of the plane you created; you'll need to turn on ray-tracing. in the object data menu for the light, open the Shadow menu and click "Ray Shadow"
• Alternate 1: Spot Lamp
1. Change the light's type to Spot.
2. Raise the light until it's covering most of the crater. If the light is not pointing down,  R otate and angle it downwards.You can also scale the radius of the light by press  S  to fit the rim of the crater.
• Alternate 2: Area Lamp
1. Change the light's type to Area.
2.  R otate along the  Y  axis: 180 degrees.
3. Set Gamma to 2.
4. Set Distance to around 5.

Experiment with the values and positioning to get something that works with your volcano.

It should now look like this:

## Varying the Terrain

Next, let's set the volcano's material.

1.  RMB  on the volcano plane.
2. Select the "Material" button and press New.
3. Change the Diffuse color to ashen gray. (Red: 0.260, Green: 0.230, Blue: 0.230)
4. Select the "Texture" button and press New.
5. Change the Type to Stucci.
6. In the Influence panel, uncheck Color, and check Normal. Set the Normal slider to 0.5. This will render the texture as a bump-map.

(Note: In version 2.77 you may need to change the texture Mapping -> Coordinates option from UV to Generated before you see bumps appear.)

(Note: In version 2.78c you may need to change the texture Mapping -> Coordinates option from UV to Global or Object before you see bumps appear.)

Older versions:

Select the volcano and press F5. Keep Pressing F5 until the Materials Buttons (symbolized by a red ball) is highlighted. Then add a new material. You do this by clicking the Add New button in the Links and Pipeline Panel. Once you've done that, set the settings similar to the picture below. Now press F6, then add a new texture to the material. Choose a stucci texture, set the noise size to 0.15. Now switch back to the materials-window (F5) and click on the "map to" tab. Deselect the "col" button and select the "nor" button. This will render the texture as a b