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some rayTest improvements in btDbvt::rayTestInternal, it avoids/reduces memory allocations during stack allocation (by sharing a persistent m_stack)

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and rayTestInternal re-uses precomputed invRayDirection/signs.
also did some performance comparison with different ray-AABB test, from 
http://jgt.akpeters.com/papers/EisemannEtAl07/

In short: it is faster, but it is not clear how to cull ray segments using ray slopes: when rays starts inside the AABB, we get a negative t value, but negatives also get false t-values...
This commit is contained in:
erwin.coumans
2008-10-16 20:00:47 +00:00
parent 60ce828419
commit 675c45f42d
4 changed files with 203 additions and 27 deletions
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46
src/BulletCollision/CollisionDispatch/btCollisionWorld.cpp
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@@ -414,6 +414,7 @@ void btCollisionWorld::objectQuerySingle(const btConvexShape* castShape,const bt
{
if (collisionShape->isConvex())
{
btConvexCast::CastResult castResult;
castResult.m_allowedPenetration = allowedPenetration;
castResult.m_fraction = btScalar(1.);//??
@@ -608,6 +609,10 @@ struct btSingleRayCallback : public btBroadphaseRayCallback
btVector3 m_rayFromWorld;
btVector3 m_rayToWorld;
btTransform m_rayFromTrans;
btTransform m_rayToTrans;
btVector3 m_hitNormal;
const btCollisionWorld* m_world;
btCollisionWorld::RayResultCallback& m_resultCallback;
@@ -617,9 +622,32 @@ struct btSingleRayCallback : public btBroadphaseRayCallback
m_world(world),
m_resultCallback(resultCallback)
{
m_rayFromTrans.setIdentity();
m_rayFromTrans.setOrigin(m_rayFromWorld);
m_rayToTrans.setIdentity();
m_rayToTrans.setOrigin(m_rayToWorld);
btVector3 rayDir = (rayToWorld-rayFromWorld);
#ifdef TEST_RAY_SLOPES
btMakeRaySlope(rayFromWorld.getX(),rayFromWorld.getY(),rayFromWorld.getZ(),rayDir.getX(),rayDir.getY(),rayDir.getZ(),&m_ray);
#else
rayDir.normalize ();
///what about division by zero? --> just set rayDirection[i] to INF/1e30
m_rayDirectionInverse[0] = rayDir[0] == btScalar(0.0) ? btScalar(1e30) : btScalar(1.0) / rayDir[0];
m_rayDirectionInverse[1] = rayDir[1] == btScalar(0.0) ? btScalar(1e30) : btScalar(1.0) / rayDir[1];
m_rayDirectionInverse[2] = rayDir[2] == btScalar(0.0) ? btScalar(1e30) : btScalar(1.0) / rayDir[2];
m_signs[0] = m_rayDirectionInverse[0] < 0.0;
m_signs[1] = m_rayDirectionInverse[1] < 0.0;
m_signs[2] = m_rayDirectionInverse[2] < 0.0;
#endif
m_lambda_max = rayDir.dot(m_rayToWorld-m_rayFromWorld);
}
virtual bool process(const btBroadphaseProxy* proxy)
{
///terminate further ray tests, once the closestHitFraction reached zero
@@ -639,20 +667,14 @@ struct btSingleRayCallback : public btBroadphaseRayCallback
collisionObject->getCollisionShape()->getAabb(collisionObject->getWorldTransform(),collisionObjectAabbMin,collisionObjectAabbMax);
#else
//getBroadphase()->getAabb(collisionObject->getBroadphaseHandle(),collisionObjectAabbMin,collisionObjectAabbMax);
btVector3& collisionObjectAabbMin = collisionObject->getBroadphaseHandle()->m_aabbMin;
btVector3& collisionObjectAabbMax = collisionObject->getBroadphaseHandle()->m_aabbMax;
const btVector3& collisionObjectAabbMin = collisionObject->getBroadphaseHandle()->m_aabbMin;
const btVector3& collisionObjectAabbMax = collisionObject->getBroadphaseHandle()->m_aabbMax;
#endif
btScalar hitLambda = m_resultCallback.m_closestHitFraction;
btVector3 hitNormal;
if (btRayAabb(m_rayFromWorld,m_rayToWorld,collisionObjectAabbMin,collisionObjectAabbMax,hitLambda,hitNormal))
//btScalar hitLambda = m_resultCallback.m_closestHitFraction;
//culling already done by broadphase
//if (btRayAabb(m_rayFromWorld,m_rayToWorld,collisionObjectAabbMin,collisionObjectAabbMax,hitLambda,m_hitNormal))
{
btTransform rayFromTrans,rayToTrans;
rayFromTrans.setIdentity();
rayFromTrans.setOrigin(m_rayFromWorld);
rayToTrans.setIdentity();
rayToTrans.setOrigin(m_rayToWorld);
m_world->rayTestSingle(rayFromTrans,rayToTrans,
m_world->rayTestSingle(m_rayFromTrans,m_rayToTrans,
collisionObject,
collisionObject->getCollisionShape(),
collisionObject->getWorldTransform(),