How to create non coliding rigid body in PhysX

Question

I need to make a NULL like rigid body in PhysX 3.2. A non-colliding one - only as an anchor point. Is there anyway to do it? I just need it to resolve some joints combination. Thanks in advance

Answer 1

First create a filter for pairs:

PxFilterFlags Simplefilter( PxFilterObjectAttributes attributes0, 
     PxFilterData filterData0, 
     PxFilterObjectAttributes attributes1, 
     PxFilterData filterData1, 
     PxPairFlags& pairFlags, 
     const void* constantBlock,
     PxU32 constantBlockSize )
     {
        if(filterData0.word0 = -99) //-99 is random                                        
        {
            return PxFilterFlag::eKILL;
        }
        pairFlags =  PxPairFlag::eRESOLVE_CONTACTS;
        pairFlags |= PxPairFlag::eCONTACT_DEFAULT;
        pairFlags |= PxPairFlag::eNOTIFY_TOUCH_FOUND;
        pairFlags |= PxPairFlag::eNOTIFY_CONTACT_POINTS;
        return PxFilterFlag::eDEFAULT;
     }

Then, while creating the PxScene add this line:

PxSceneDesc sceneDesc(gPhysicsSDK->getTolerancesScale());
...
sceneDesc.filterShader = Simplefilter;
gScene = gPhysicsSDK->createScene(sceneDesc);

Finally, make the shapes of your actor (gSphere in my example) not collidible by:

unsigned int nbShapes = gSphere->getNbShapes();

PxShape** shapes = new PxShape*[nbShapes];
if(nbShapes > 0)
{
    gSphere->getShapes(shapes,nbShapes,0);
    for(unsigned int j = 0; j< nbShapes; j++)
    {
        PxFilterData data;
        data.word0 = -99; // the same number above

        shapes[j]->setSimulationFilterData(data);
    }
}