Real-Time Physics Simulation Forum

I'm not sure. I am not familiar with that struct. This sounds like a different question though, in which case it's best to make a new post.

Glad to help. On a related note, another theory I had about the rarely seen positive contact point distances was if the shape margins - but not the shapes themselves - are overlapping. These margins are typically very thin. Not sure though. Maybe someone else has figured it out and can enlighten us ...

I've also considered doing (numContacts > 0) as opposed to checking their distances, though from some testing I've found that sometimes contact points have a positive distance, which means they do not actually represent a shape overlap. This seems to occur for a very short time when objects are movi...

Yes. Assuming, of course, that the shape is part of a btCollisionObject:

btCollisionObject::setWorldTransform(btTransform &worldTransform)

I don't believe so. Instead, just use a very flat box shape.

mm try btGImpactMeshShape instead. It is supposed to be for dynamic meshes, while btBvhTriangleMeshShape is meant for static meshes (though frankly I've had times where btBvhTriangleMeshShape seems to work better, so who knows). Though this may not be the cause of your problem.

Yeah I think you'd want to check out systems specialized for particle systems (like the OpenCL demo). Loading/unloading rigid bodies based on aabb overlap might not be an efficient approach depending on how dense your particle system is (in a sufficiently dense system you could have frequent loading...

Could you provide more information about the error? What is the assertion that failed?

Unless I am mistaken, I think SPH is more about simulating fluids (as many particles) or perhaps interactions between objects in fluids. That wouldn't solve the question of how to have the undulating flowing motion (though it could still add some nice effects to collections of interacting objects fl...

If you give your rigid bodies a constant linear damping of some value between 0 and 1 (maybe something like 0.9) and then intermittently apply a force to them in the desired direction of flow, I would think that would give the undulating flow motion.

I imagine you could perhaps intercept the total force to be applied on a body at each time step, project its vector onto the plane of interest, and then let Bullet continue using that projection as the force to be applied. The code would be quite simple, though offhand I'm not sure where you would i...

I'm looking for confirmation/clarification of how I think manifold contact points work. From testing and from what I've read, it seems that a manifold (btPersistentManifold) is created for 2 bodies as long as their aabb's overlap. I also understand that if the manifold has no contact points, the act...

Hm, you're right. I just tried it out and the sphere bounces nicely on a plane, but only a little bit or not at all when dropped on a box shape (with the exact same rigid body settings as the plane). Offhand I don't know why...though I seem to recall this being discussed before. I know other people ...

In the HelloWorldApp, the object is to get a ball bouncing on a box right? If I wanted to test a plane, could I just add in a btCollisionObject with a btStaticPlaneShape instead of the box? In the current version of the Hello World tutorial I see, it is already using btStaticPlaneShape, not btBoxSh...

Hm I'm not sure one is able to get something like the shape of the collision intersection. Also keep in mind that convex primitives (boxes, spheres, cones, etc) do not have triangles. They are implicit representations of a shape. Interesting painting idea though. One random thought about how you mig...