I’m using Jitter Physics to create a game. For testing, I have ball (a spherical rigid body) falling onto a small box-like mesh. The problem is that the ball falls straight through the floor, even though the collision seems to be detected properly. The mesh’s rigid body is created using a triangle mesh shape. In the code below, model is the floor’s 3D model Octree octree = PhysicsUtilities.ExtractOctree(model); octree.BuildOctree(); Body body = new RigidBody(new TriangleMeshShape(octree)); body.IsStatic = true; The PhysicsUtilities.ExtractOctree function extracts vertices from the 3D model in order to create the rigid body. As far as I can tell, that function is working correctly (i.e. all vertices and indices look correct). To check if the collision was detected, I added a callback function as follows. CollisionSystem collisionSystem = new CollisionSystemSAP(); collisionSystem.CollisionDetected += OnCollisionDetected; World world = new World(collisionSystem); The ball-floor collision is detected and everything about the collision looks correct. I’ve even tried changing values in world.ContactSettings, but nothing worked. Has anyone else experienced this problem? I’ve tried everything I can and Jitter’s documentation is pretty low.