1. Start by finding a very good map of the track you want to create or simply
draw one yourself
2. Gather as much data of the elevations you can get. It is
very hard to correct any mistakes you make in elevations afterwards!
3. Fire
up 3ds MAX
4. Draw the layout as a simple line. use "smooth" type and use as
few vertices as is possible to avoid complex curves;
5. You can finetune the line by selecting a
vert, click right mouse and select "bezier". Now you can use the handles to
control the curvature;
6. Position the vertices along the z-axis to create
the elevations. You can also rotate the handles to control the curvature in the
z-plane;
7. Create a shape from a simple "corner" type line. This will be the
cross-section of your track. In the example there is one segment for the road
(vertices are highlited), the others are for the inner-grass, walls, outer-grass
and fences. You might want to extend even more segments for grass outside the
fence.
IMPORTANT: give each segment a different material ID ! We'll use this
later on. You can give some segments the same material ID if the are oriented
the same (wall sides etc).
8. Select
the layout line and choose "compound objects"-> "loft"
9. Select "Get Shape" and click on the
shape you just created. Voila, You will already see a 3d trackshape
appear.
However, there are some things
to adjust:
10. Open the "Skin parameters" rollout
11. Enter "0" for Shape
Steps.
12. Increase "Path Steps" until you have smooth corners everywhere.
This will determine your eventual polycount, so choose wisely! Check in 3d as
well, since it may look smooth in the editor, but in the game the corners can
look very crude. You will now have something similar like this:
There are some interesting parameters in
the rollouts to toy with however:
-Contour: must be turned
on
-Banking: Usually turned off, we'll use other ways to create
banking
-Constant cross section: what it says...
-Flip normals: Sometimes
the faces on the track are inverted
13. Adding banking and stuff. In the
"Path parameters" rollout choose "path steps". You will see a yellow dot on the
track which is the position of your current shape (A loft is a whole lot of
shapes/cross sections tied together). With the up and down button you can
navigate the dot along the track.
Select a shape and select "Get Shape" again
and click on the original shape you used. You will see the shape appear in the
place where the yellow dot is (when you're editing that is, otherwise it's
invisble).
Move the yellow dot some distance from the point where you added
the "new shape" and select "Get Shape" again and click on the original shape.
When all is well, no changes where made to the track. You just defined two extra
shapes in the loft, but since they are the same as the original nothing
happens.
Now comes the fun part: Select one of the "new" shapes: In the
modifier menu choose "shape" as sub-object.
Now select a shape by clicking or using
the selection box (somehow I can't see them when they are not selected). It is
now possible to Scale or Rotate that shape and you will see that the loft will
change:
View while editing the shape:
View after editing:
14. You can now apply a material to the
loft and work on the uv mapping:
In the "surface parameters" rollout
select "Generate material ID's", "Use Shape ID's" and "Apply mapping". Now
change "length repeat" and "width repeat" to get some sort of presentable
mapping on your track. If you have used a material with multiple
textures/material ID's you'll get the idea...
The UV mapping isn't finished,
but because you gave each segment a different material ID it's very easy to
select the faces (once it's a mesh) you want by using "Select by ID".
To
get the track in the game you have to collapse the loft to a mesh (make a copy
first) and cut the track up in parts. Use big parts for initial testing and keep
the original layout line/shape and loft! That way you can always change parts
later on.
The actual exporting to MTS etc. is already coverd in other
tutorials....