[ODE] fall through a TriMesh

Simon Adler s.adler at sensator.com
Mon Oct 17 15:39:12 MST 2005


I need some help with TriMesh Collision. I already looked at
the examples, but my objects are falling through the Trimesh.
I've a not plane Ground as a TriMesh and an Object with a
Box as Geom.

My Object if falling through the Ground and I've no Idea why.
I hope for some help or some Ideas how I can debug this.

All Densities are 5.0

My Callback Code:
    const int NoCollision = 100;
    dContact * hitspace = new dContact[NoCollision];
    int hits = dCollide(geom1, geom2, NoCollision, &hitspace[0].geom,

    while (hits--)
        hitspace[hits].surface.mode = dContactBounce | dContactSoftCFM;
        hitspace[hits].surface.mu = dInfinity;
        hitspace[hits].surface.mu2 = 0;
        hitspace[hits].surface.bounce = 0.0f;
        hitspace[hits].surface.bounce_vel = 0.1f;
        hitspace[hits].surface.soft_cfm = 0.01f;

        dJointID joint = dJointCreateContact(world->id, ContactGroup ,
        dJointAttach(joint, GeomGetBody(geom1), GeomGetBody(geom2));
      delete[] hitspace;

If enabled Gravity just for my Object and not for the Ground.

I've a second thought. What If my Object collides, how can I fix the
Ground, so the ground is not moving, because something hit the Surface.

I found something interesting. If my Object hits the TriMesh, the callback
is called, but (hits == 0). I read something about normal Problems
by the Vertexorder, so I tried to collide from the other side, but the
Problems are still there.

I will be greatfull for any advice

Simon Adler

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