bool BVH4BuilderFast::splitParallel(BuildRecord ¤t, BuildRecord &leftChild, BuildRecord &rightChild, const size_t threadID, const size_t numThreads)
{
const unsigned int items = current.end - current.begin;
assert(items >= BUILD_RECORD_SPLIT_THRESHOLD);
/* mark as leaf if leaf threshold reached */
if (items <= QBVH_BUILDER_LEAF_ITEM_THRESHOLD) {
current.createLeaf();
return false;
}
/* use primitive array temporarily for parallel splits */
PrimRef* tmp = (PrimRef*) primAllocator.base();
/* parallel binning of centroids */
g_state->parallelBinner.bin(current,prims,tmp,threadID,numThreads);
/* find best split */
Split split;
g_state->parallelBinner.best(split);
/* if we cannot find a valid split, enforce an arbitrary split */
if (unlikely(split.pos == -1)) split_fallback(prims,current,leftChild,rightChild);
/* parallel partitioning of items */
else g_state->parallelBinner.partition(tmp,prims,split,leftChild,rightChild,threadID,numThreads);
if (leftChild.items() <= QBVH_BUILDER_LEAF_ITEM_THRESHOLD) leftChild.createLeaf();
if (rightChild.items() <= QBVH_BUILDER_LEAF_ITEM_THRESHOLD) rightChild.createLeaf();
return true;
}
bool BVH4BuilderFast::splitSequential(BuildRecord& current, BuildRecord& leftChild, BuildRecord& rightChild)
{
/* mark as leaf if leaf threshold reached */
if (current.items() <= QBVH_BUILDER_LEAF_ITEM_THRESHOLD) {
current.createLeaf();
return false;
}
/* calculate binning function */
Mapping<16> mapping(current.bounds);
/* binning of centroids */
Binner<16> binner;
binner.bin(prims,current.begin,current.end,mapping);
/* find best split */
Split split;
binner.best(split,mapping);
/* if we cannot find a valid split, enforce an arbitrary split */
if (unlikely(split.pos == -1)) split_fallback(prims,current,leftChild,rightChild);
/* partitioning of items */
else binner.partition(prims, current.begin, current.end, split, mapping, leftChild, rightChild);
if (leftChild.items() <= QBVH_BUILDER_LEAF_ITEM_THRESHOLD) leftChild.createLeaf();
if (rightChild.items() <= QBVH_BUILDER_LEAF_ITEM_THRESHOLD) rightChild.createLeaf();
return true;
}