User:Kisubo:sandbox

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(This is a sandbox for user Kisubo 13:09, 6 February 2006 (UTC))






Next Page: Edit Mode HotKeys Review
Previous Page: Modeling a Gingerbread Man

This tutorial needs some more explaining as to what is going (and why) in section 4.

In the following tutorial, you will use:

  • polygon mesh
  • face loop cutting
  • spin dup
  • subdivision surfaces
  • subdivision creases
  • bevel
  • set smooth
  • multiple materials
  • extrusion
  • merge vertices
  • remove doubles
  • constraints


1. Press NUM-1, 7 or 3 then SPACE →add→mesh→cube to make a cube aligned to the axes.


2. Hit tab to go into edit-mode and select all faces to prevent bevel messing up normals. Hit WKEY->bevel, recursion->1 (you'll see why later) then choose bevel size. Bevel of 0.15 is ok.
DieAnotherWay2.png

3. In editmode, go to the Editing tab (F9) and look at the mesh tools 1 panel. In Blender 2.37, there is a set of buttons for edge measuring. Turn on Edge Length and note the length of one of the sides of the square faces. This should be 1.7 if the above settings were used.
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4. A typical die has a grid of 9 possible positions for the dents and the gap between the dents is the dent radius (or half the diameter). So, there are conveniently 10 units on each edge of the square faces, where the gaps use 4 of the units and the 3 dents use two each. This means the gaps are of size 1.7/10 = 0.17 and the dents (1.7x2)/10 = 0.34.
9 posiciones.jpg
Muescas y espacios.jpg


5. To make these segments, use the face loop cut tool. Press KKEY->face loop cut and select one of the edges.
DieAnotherWay5a.png

click and you get a blue line to position.
DieAnotherWay5b.png

Because it's very difficult to position using percentages, especially after the first segment is made because you then have to work out percentages of what's left but also because you can't seem to input exact values, place the blue line to the far left edge and click once. Do not click again because this line is on top of another one and it will be tricky to select it again. If you make a mistake, hit UKEY or CTRL+ZKEY to undo.

Now press GKEY then YKEY to move the line along the axis (this is why the cube needed to be aligned to the axes first). I'm using YKEY because of the way my cube is setup - the blue line moves along the green axis. If you've done it another way round, use the appropriate axis.

After hitting GKEY, YKEY, enter the exact value of the gap that we measured (0.17) and hit return - if you make a mistake before hitting return, hit delete and retype the number or press UKEY or CTRL+ZKEY after hitting return.

Select the remaining segment to the right of the line, cut this and move the blue line as far as you can, which will be to the line you just made. Move this line to 0.34 along y because it is where the dents go.

6. Repeat step 5 with the remaining segment until you have made 6 cuts of alternating size (0.17, 0.34, 0.17, 0.34, 0.17, 0.34) and get something like this:
DieAnotherWay6.png

7. Now turn the cube round and do step 5 for the adjacent edge until you get the grid forming. Note, you move the cuts along the x-axis now so do GKEY, XKEY, 0.17 etc. Don't worry if the last edge says 0.169 instead of 0.17.
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You can see the grid of 9 squares mentioned earlier:
DieAnotherWay7b.png

8. The problem here is that it is very time consuming to do this for the remaining 5 sides of the die. Instead, we will just duplicate the one we have done already. But first the rest needs to be deleted. So go into front view (NUM1) and orthographic mode (NUM5). Also turn off depth buffer clipping. Use vertex select mode and select the bottom vertices:
200px
Make sure these are the right ones by rotating your view with the middle mouse button. Now press x and select 'vertices'. This should leave only the top side of the die:
200px
We now have to duplicate and rotate this side. There is a very handy tool to save doing this manually called spin dup located in the editing tab (F9) in the mesh tools panel. We want to duplicate the side 3 times in both the x and y axes to complete the cube - 3 times isn't necessary in the second axis because we will already have a bottom side but it's easier that way.

Spin Dup works relative to your camera and the cursor. So, put the camera into front view (NUM1) and orthographic mode (NUM5). If you haven't moved the cube, the 3D cursor should be at the center of the cube (at the pink dot). If not, go into object mode (TAB) and select what's left of the cube and press SHIFT+S and select 'cursor to selection'. You can also manually move the cursor by going to the view menu -> view properties and editing the 3D cursor position. In this tutorial, it should be at (0,0,0).

The settings for spin dup are that we need 3 duplicates over a 270 degree rotation with 1 turn. Now press spin dup to get the following:

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You will see the currently selected side is no longer the top side. This means we have to go into top view and duplicate around the z-axis so go into top view (NUM7) and hit spin dup again to fill the remaining sides.

9. There will now be a few overlapping points. To get rid of these, go to the editing tab again (F9) and in the mesh tools, there is a button called rem doubles. Select all the vertices by pressing AKEY and select remove doubles. This may leave some overlapping points because the threshold for removing doubles is set at 0.001 and some points might be just outside that value. Setting it to 0.003 should get rid of all the doubles to leave the die with 384 vertices (this information is at the top of the Blender window). You can check by counting that each side has 8x8 vertices and there are 6 sides on the cube.

200px

10. The die needs the dents added. Select one of the faces where a dent would go and extrude the face by hitting EKEY and then ESC. Do not click after hitting EKEY. Collapse this face by using ALT+M to merge the 4 corners of the extruded face into the centre where it will tell you you have removed 3 vertices. You should get the following:
DieAnotherWay10a.png
 Do this for the configuration of the dots on that side. So for example, 5 would look like this:
DieAnotherWay10b.png

11. Select one of the edges of the dents to check the size is 0.34.
200px
Remember the dent radius was 0.17. We need to use this value to lower the centre point of the dents down. Select all the 5 centre points at once to save time and move them inwards by 0.17. The side I put the 5 dents on here was the top so I move the vertices inwards by pressing GKEY,

ZKEY, -0.17 and hitting ENTER. I then get this:

DieAnotherWay11b.png

12. TAB out of editmode. If you haven't done this already, hit set smooth in the editing panel and turn on subdivision surfaces
200px
It should look something like this:
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13. On a die, the edges of the dents are usually sharp so we'll use subsurface creasing to do that.

Go back into editmode and with the edge select mode on, select all the perimeters of the dents like so (it may help to turn off subsurf for the moment):
DieAnotherWay13.png
Press SHIFT+EKEY to enable creasing and move the mouse until the display says crease is at 1.  After pressing SHIFT+EKEY, you can then set crease values in the information box that you get by pressing NKEY when objects are selected. This can be useful to check if all the edges have the right crease because it gives you the average crease value and if it is less than 1, there is an edge wrong.

14. Repeat steps 10,11 and 13 for all the sides of the die. REMEMBER, a die is numbered so that opposite sides add up to 7. In my example, that means I put 2 on the bottom etc. Once you finish, if you turn on subdiv level 2, you will get something like this:
DieAnotherWay14.png

15. You can make a test render now to see that the dents look the right size and the bevel is right. So, turn the subdivision level for the rendering up to 3. To help position the camera so that you centre the die, you can make the camera look at the die by adding a track-to constraint to it. I prefer to track an empty though, because it is more flexible.

Make an empty by going into top down view (NUM7) and hitting SPACE → add → empty. It's always best to go into one of the set orthographic views so as to align new objects to the axes. If you add something misaligned, just go to the object menu then clear/apply > clear rotation (or ALT+RKEY). Because the empty was created at the origin, you might not be able to see it as it is inside the die. Hit ZKEY to enable wireframe mode and select the empty. Just move it outside the cube until we get the constaint set up.

To add a track-to constraint, select the camera first then SHIFT+RMB the empty and press CTRL+TKEY and choose track-to from the list. Move the empty back inside the die. You edit constraints in the object tab (F7). Add a couple of lamps (both intensity 1) to get the scene like this or feel free to experiment with a more advanced lighting setup:

DieAnotherWay15.png

16. To render, set the size of the image you want. 800x600 is a decent size so put these settings in the format panel in the Scene tab (F10). In the render panel, make sure 100% is selected. If it's 50%, the render will come out as 400x300. For preview renders, don't turn on OSA, which is anti-aliasing because it slows your renders down significantly. Try to only use it for a final render.

Another way to position the camera is by selecting it and then looking through it as you move it. Look through the camera by pressing NUM0. Use the GKEY to pan across and rotate around the local axes of the camera by pressing say RKEY,XKEY,XKEY to rotate in x axis. To zoom in and out press GKEY, ZKEY, ZKEY. The mouse wheel zoom moves your view towards and away from the camera.

Another important point is to set the image format. This is done in the format panel. The listbox has a number of image types. I find that png is generally the best because it is lossless and offers the highest compression among the lossless formats. It also supports an alpha channel for transparency. When rendering an animation, it is better to render as an image sequence than as a movie because it is easier to edit these and repair broken frames. Quicktime supports loading of image sequences and you can save as a movie using a wide range of compression formats.

To save the render, go to the file menu → save image and type in the full name of the image including the extension e.g. die.png.

The output should now be looking something like this:
200px

17. To give it some colour, we will need to use multiple materials because a typical die has dents that are a different colour from the die itself.

Go to the editing section in the button panel again and make sure the die is selected. In the links and materials panel, there is a section for materials and the number in the box should be at zero. It may be at 1 if you have assigned a material to the object already. Add enough to make 2 materials in total.

Go back to the Shading panel (F5) and there is a box at the very top of the material panel with the number 2 beside it. Click this number to make the two materials you've just created independent. Use the arrows to the right of the ME button to switch materials.

Make material 1 bright red by just picking red in the colour picker or by setting the RGB sliders. Make material 2 white by doing the same. Or pick whatever colour you prefer and material settings.

18. These colours need to be assigned to the right parts of the die.

Go into editmode and turn off subsurf to help. Select the inner faces of the dents - if you accidentally don't press the SHIFT, press CTRL+ZKEY or UKEY to undo. Once they are all selected, go to the Editing tab again and the material panel. Select the colour for the dents. There is a button that says assign - press it and it will make the dents white but the die remains red. Turn subsurf back on and render with OSA (only put it up as high as you need for the resolution of the image you are rendering):
DieAnotherWay18.png

Extra:
The reason I modelled the die this way is because it is also very easy to change the sizes of the components e.g. the bevel and the dent size. You do this by selecting the vertical or horizontal segments and just scaling them in one axis. Here we will reduce the dent size and the bevel by half.

Go into front view (NUM1), turn off clipping and select a line containing dents. Then just scale in one axis e.g. SKEY, XKEY, 0.5. Remember to have your pivot point set to median:
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Do this horizontally and vertically around the die. You should need to scale 9 times for the dents and 6 times for the bevel:

200px
You may need to add extra geometry once you are satisfied with the sizes of the dots and the bevel so that the edges of the die don't look warped due to the subdivision. You can use face loop cut again for that and add extra lines in the middle of the gap segments.
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Previous Page: Modeling a Gingerbread Man