Real-Time Physics Simulation Forum

Ah, are convex hulls that stable in Bullet? That is really nice!

Hmm, I gave the use of addTriangle a try, but that did not change anything: still the exact same crash. I think I am going to try to add code to the Bullet source to see what kind of data is being added to the list that crashes. I am still not sure whether the bug is in my code or in Bullet code (al...

Might someone have time to check whether the BVH code is correct?

One way would be to create vertical collision triangles on each of the edges. However, triangles are relatively instable compared to collision boxes, because they are infinitely thin. Therefore instead you could make the walls with collision boxes, but you would have to be carefull at corners of mor...

I don't know the exact formula, but I think you need to take a look at the intertia tensor and do something with that. The intertia tensor is like mass, only for rotation. So if the x in the interia tensor is very high, then rotating over the x-axis requires a lot of force. It seems like rotating to...

Instead of directly changing the lineair velocity, you could also try applying a force. That is more "physics-like" and might work better.

Hmm, memory problems with the bvh sounds like a logical cause for the problem. However, I am not aware of what I am doing wrong there and debug mode does not tell me that something is wrong there. Could you have a look at my code for filling the bvh? This is the code (it copies vertices from the gra...

Doing that would cost a lot of time, as the whole thing is already quite complex. Also, I depend on graphics libraries to create triangle meshes for collision detection. Can you not give me some pointers what might be going wrong here? Is the problem really in this code, or might some other part of ...

Does no one have a clue what is causing this crash?

I am getting a crash deep inside Bullet code. The crash happens in the function bool MyContactDestroyedCallback(void* userPersistentData). This is the error I am getting: "Unhandled exception at 0x78160f82 in IceMagnet.exe: 0xC0000005: Access violation reading location 0xfffffff8." The wei...

I think I am getting it now. The problem is, I think, that the one object cannot move without the other, so if one is given a speed, then it must propagate part of that speed to the other. I would expect dampened movement because of that, however, not no movement at all. Have you tried using the app...

Air friction is incredibly difficult to do, because it depends on the shape of the object and the angle under which it is moving and in fact also on things like turbulence and material smoothness. Simulating that correctly is something I never heard of anyone doing for games or something real-time, ...

Bullet would only be of help with particle systems if you were really doing physics on them, like forces or collisions. However, most games do not do that at all. Most games do not do particle collisions (although on multicore it is becoming more mainstream these days). The most interesting aspects ...

Deleting and removing from the simulation are separate steps. Can't you remove an object from the simulation through dynamicsWorld->removeCollisionObject(banana); and then instead of deleting it, inserting it's pointer in a std::vector (i.e. a memory pool, indeed). Later on, you can grab it from the...

Didn't you mean to ask "Can no one help me?" ;) Anyway: I still am not sure I understand your question. Is the problem that you want object A get a certain speed, but you want object B to be modified through the constraint instead of doing it directly? That sounds like you need to apply ex...