private void PreallocateChildAlgorithms(CollisionObject body0, CollisionObject body1)
{
CollisionObject colObj = m_isSwapped ? body1 : body0;
CollisionObject otherObj = m_isSwapped ? body0 : body1;
Debug.Assert(colObj.GetCollisionShape().IsCompound());
CompoundShape compoundShape = (CompoundShape)(colObj.GetCollisionShape());
int numChildren = compoundShape.GetNumChildShapes();
int i;
//m_childCollisionAlgorithms.resize(numChildren);
m_childCollisionAlgorithms.Clear();
for (i = 0; i < numChildren; i++)
{
if (compoundShape.GetDynamicAabbTree() != null)
{
m_childCollisionAlgorithms.Add(null);
}
else
{
CollisionShape tmpShape = colObj.GetCollisionShape();
CollisionShape childShape = compoundShape.GetChildShape(i);
colObj.InternalSetTemporaryCollisionShape(childShape);
CollisionAlgorithm ca = m_dispatcher.FindAlgorithm(colObj, otherObj, m_sharedManifold);
m_childCollisionAlgorithms.Add(ca);
colObj.InternalSetTemporaryCollisionShape(tmpShape);
}
}
}
public override void ProcessCollision(CollisionObject body0, CollisionObject body1, DispatcherInfo dispatchInfo, ManifoldResult resultOut)
{
//resultOut = null;
CollisionObject colObj = m_isSwapped ? body1 : body0;
CollisionObject otherObj = m_isSwapped ? body0 : body1;
Debug.Assert(colObj.GetCollisionShape().IsCompound());
CompoundShape compoundShape = (CompoundShape)(colObj.GetCollisionShape());
///btCompoundShape might have changed:
////make sure the internal child collision algorithm caches are still valid
if (compoundShape.GetUpdateRevision() != m_compoundShapeRevision)
{
///clear and update all
RemoveChildAlgorithms();
PreallocateChildAlgorithms(body0, body1);
}
Dbvt tree = compoundShape.GetDynamicAabbTree();
//use a dynamic aabb tree to cull potential child-overlaps
using (CompoundLeafCallback callback = BulletGlobals.CompoundLeafCallbackPool.Get())
{
callback.Initialize(colObj, otherObj, m_dispatcher, dispatchInfo, resultOut, this, m_childCollisionAlgorithms, m_sharedManifold);
///we need to refresh all contact manifolds
///note that we should actually recursively traverse all children, btCompoundShape can nested more then 1 level deep
///so we should add a 'refreshManifolds' in the btCollisionAlgorithm
{
m_manifoldArray.Clear();
for (int i = 0; i < m_childCollisionAlgorithms.Count; i++)
{
if (m_childCollisionAlgorithms[i] != null)
{
m_childCollisionAlgorithms[i].GetAllContactManifolds(m_manifoldArray);
for (int m = 0; m < m_manifoldArray.Count; m++)
{
if (m_manifoldArray[m].GetNumContacts() > 0)
{
resultOut.SetPersistentManifold(m_manifoldArray[m]);
resultOut.RefreshContactPoints();
resultOut.SetPersistentManifold(null);//??necessary?
}
}
m_manifoldArray.Clear();
}
}
}
if (tree != null)
{
IndexedVector3 localAabbMin;
IndexedVector3 localAabbMax;
IndexedMatrix otherInCompoundSpace;
//otherInCompoundSpace = MathUtil.BulletMatrixMultiply(colObj.GetWorldTransform(),otherObj.GetWorldTransform());
otherInCompoundSpace = colObj.GetWorldTransform().Inverse() * otherObj.GetWorldTransform();
otherObj.GetCollisionShape().GetAabb(ref otherInCompoundSpace, out localAabbMin, out localAabbMax);
DbvtAabbMm bounds = DbvtAabbMm.FromMM(ref localAabbMin, ref localAabbMax);
//process all children, that overlap with the given AABB bounds
Dbvt.CollideTV(tree.m_root, ref bounds, callback, tree.CollideTVStack, ref tree.CollideTVCount);
}
else
{
//iterate over all children, perform an AABB check inside ProcessChildShape
int numChildren = m_childCollisionAlgorithms.Count;
for (int i = 0; i < numChildren; i++)
{
callback.ProcessChildShape(compoundShape.GetChildShape(i), i);
}
}
{
//iterate over all children, perform an AABB check inside ProcessChildShape
int numChildren = m_childCollisionAlgorithms.Count;
m_manifoldArray.Clear();
CollisionShape childShape = null;
IndexedMatrix orgTrans;
IndexedMatrix orgInterpolationTrans;
IndexedMatrix newChildWorldTrans;
for (int i = 0; i < numChildren; i++)
{
if (m_childCollisionAlgorithms[i] != null)
{
childShape = compoundShape.GetChildShape(i);
//if not longer overlapping, remove the algorithm
orgTrans = colObj.GetWorldTransform();
orgInterpolationTrans = colObj.GetInterpolationWorldTransform();
IndexedMatrix childTrans = compoundShape.GetChildTransform(i);
newChildWorldTrans = orgTrans * childTrans;
//perform an AABB check first
IndexedVector3 aabbMin0;
IndexedVector3 aabbMax0;
IndexedVector3 aabbMin1;
IndexedVector3 aabbMax1;
childShape.GetAabb(ref newChildWorldTrans, out aabbMin0, out aabbMax0);
otherObj.GetCollisionShape().GetAabb(otherObj.GetWorldTransform(), out aabbMin1, out aabbMax1);
if (!AabbUtil2.TestAabbAgainstAabb2(ref aabbMin0, ref aabbMax0, ref aabbMin1, ref aabbMax1))
{
m_dispatcher.FreeCollisionAlgorithm(m_childCollisionAlgorithms[i]);
m_childCollisionAlgorithms[i] = null;
}
}
}
}
}
}