[ODE] Trimesh problems

[Geoff Carlton]

The standard Trimesh code has some problems - for example, colliding 
objects with a completely flat trimesh will end up with many 
non-vertical contact normals.  This occurs because the flat triangles 
try to push the sphere "away" towards an edge, sometimes with almost 
horizontal normals.  Its unworkable in its current form, and I can't see 
how anybody uses it without hacking away into the code in ODE (as I did).

Thanks,
Geoff

Anders Olofsson wrote:

>Well, I did my little test, download it here (254 kb, source and windows 
>exe, OpenGL):
>
>http://www.biologigrand.ac/lgh255/trimeshtest.zip
>
>Keyboard input:
>
>Steering: W,A,S,D and mouse
>Toggle wireframe/fill: F
>3 different scenes: 1, 2, 3
>
>Scene 1: just a plane (normal 0,1,0)
>Scene 2: 2 large triangles (normals 0,1,0)
>Scene 3: 2 small triangles (normals 0,1,0)
>
>In scene 1 the 2 spheres stop bouncing, in scene 2 the spheres starts to 
>jump after a few seconds and scene 3 seems to work like the plane scene.
>
>So large triangles is causing some problems. Haven't someone else 
>discovered this?. I'm probably doing something wrong!, but what?
>
>Thanks for helping!
>
>--Anders Olofsson
>
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