Blender 3D: Noob to Pro/Quickie Texture

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This tutorial was created using Blender v2.49

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. This tutorial uses the file from the previous tutorial. If you didn't do it before, go back and do it now.

A texture may be an image or 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.

[edit] Adding a texture

The file we're working with has a texture already, but if you add a new material to an object, it hasn't got a texture by default. Then add a texture:

• In the Texture panel of the Material buttons click on Add New to add a new texture, or select an existing one with the Drop-Down button.
• Select the Texture Buttons with the spotty square icon (or by pressing F6).
• Select the texture type Clouds from the drop-down list. You can also change the texture's name, as we have done for the material.

A preview appears, as well as some parameters to experiment with. A Clouds texture provides some irregularities.

• Head back to the Material Buttons (Click the red sphere or press F5) and a colored preview of the texture appears. It is purple! All new textures default to this colour.

On the right hand side of the material buttons window there are three tabs: Texture, Map Input, and Map To. Since we want to change a material property that is affected by the texture we have to look at the Map To tab. This means: map the value that a texture provides to a material property. A texture may provide different values:

1. RGB color (all images, Magic, every texture with a colorband)
2. Intensity, either as grey scale or/and an alpha value (most of the procedural textures, image textures with alpha, textures with a colorband)
3. Normal values (Stucci, normal maps)

If you want to use textures you always have to be aware of the value a texture provides and the Map To settings for the material.

• Select the Map To panel.

The activated Col button in the top row shows that the texture affects the color of the material. A Clouds texture provides an intensity value, ranging from 0 (where the texture is black) to 1 (where the texture is white).

The RGB (Red, Green, Blue) sliders here adjust the target color of the texture. This is mixed (Mix) with the material color, where the intensity of the Clouds texture is 1 only the target color is used, where the intensity of the Clouds texture is 0, only the material color is used.

• Set the target color to black.

Procedural textures are not shown in the 3D window (only if you would use excessive amounts of vertices), even if you use GLSL materials. This means that we have to render the image to see the texture properly.

• Render the image (F12), or use the preview to judge the result of the texture.

Next we will add a Stucci texture to make our clouds look bumpy.

[edit] Adding a Stucci texture

• Go back to the Texture Buttons and select the next texture channel (one of the blank buttons under "NewCloudTexture").
• Add a new texture here and set the type to Stucci.
• Back to the Material Buttons, and click the "Map To" tab.
• Turn Col off and Nor on.

Col means the texture affects the colour. Nor means it affects the rendered normal, i.e. the angle the renderer treats the surface as - creating fake shadows on the surface.

• Play with the Nor slider, but leave it on about 4.

Render to see the effect. A texture changing the surface normal is called a "Bump" map or "Normal" map. Since that is fake 3D, you don't see it under every circumstance, you will get a greater effect on smoothly curved surfaces with high specularity, only a little or no effect on flat surfaces with low specularity.