Real-Time Physics Simulation Forum

There are a couple of ways to do this one way is to implement is world->setInternalTickCallback( tickcallback, user_data ) and tickcallback()will be called after every tick and you can do the processing there or if you want the callback to be called after the collision point is processed there's a g...

thank you - it seems to work.

I am assuming this is what you want
and iterate through the collision manifolds

from the dispatcher
There are some demos which do this. CollisionInterfaceDemo is something which does this.

Thanks
Ram.

Thanks Erwin. I will look into patching GImpactShape and in the meantime also submit an issue tracker for that.

Ram.

Hi, I was wondering if its possible detecting self collisions for deformable bodies using GImpact or any other object in Bullet. It seems to be possible to use btSoftBody for self collisions but ideally I would like to use only collisions and not the solver. I would really appreciate any pointers on...

thank you flix, I will try your suggestions and post my findings when i have them. Yes, I had registered the GImpact collision algorithm.

ram.

hello, i was wondering if anyone has experience of dynamically updating GImpact Mesh shape vertices for doing collision detection of deforming bodies. i was wondering what is the exact procedure for modifying GImpact mesh vertices before doing a postUpdate(). when i looked at the concave demo which ...

hello, thanks for your demo. i am trying to use GImpact shapes with GImpact, both deforming shapes as collision shapes..., I update the positions and am calling postUpdate(), but for some reason the collision detection fails. i was wondering what you had to do in special to get bullet to recognize c...

Yes, I was able to get it to work with modifications to bullet. In bullet 2.70 source code under the directory /src/BulletDynamics/ConstraintSolver and filename btGeneric6DofConstraint.cpp I changed the following line m_linearLimits.solveLinearAxis( m_timeStep, jacDiagABInv, m_rbA,pointInA, m_rbB,po...

In my personal experience there are a few things which have to be done in order to trigger collision detection between kinematic & static objects and to populate the contact manifold with these objects as well included The mass has to be set to some value for these objects and then the collision...

In line with this, the solveGroup func doesn't seem to set the m_appliedImpulse for the manifold point. It seems to be set only in solveGroupCacheFriendly, Is that on purpose ? So, If the contact solver info is not set to cache friendly, then the m_appliedImpulse for the manifold point always seems ...

Thanks for your response Erwin. Actually in running more tests constraining between STATIC & DYNAMIC objects do seem to operate properly. However my issue might be something different. It is because of my system being over constrained and due to the sequential nature of the constraint handling i...

There is probably an obvious answer to this question , my apologies. I was wondering if its possible to constrain dynamic objects to static objects. (since static objects have mass=0, I am curious how its handled). When I tried it out, there were no errors, but it didn't seem like the constraints we...

I use m_appliedImpulse on the btManifoldPoint from looping through the list from btDispatcher::getInternalManifoldPointer()...and it seems to be getting valid values and not 0. but on browsing the bullet source code I can see a situation where the m_appliedImpulse can be 0. my is observation is base...

I guess I can answer my question based on what I found. btPersistantManifold's getNumManifolds() seems to indeed point to the number of Broadphase collisions which seemed to have happened and the manifold's getNumContacts() seems to report the number of actual contacts in the Narrowphase collision c...