void Octree::Update()
{
PROFILE(UpdateOctree);
for (auto it = updateQueue.Begin(); it != updateQueue.End(); ++it)
{
OctreeNode* node = *it;
// If node was removed before update could happen, a null pointer will be in its place
if (node)
{
node->SetFlag(NF_OCTREE_UPDATE_QUEUED, false);
// Do nothing if still fits the current octant
const BoundingBox& box = node->WorldBoundingBox();
Vector3 boxSize = box.Size();
Octant* oldOctant = node->octant;
if (oldOctant && oldOctant->cullingBox.IsInside(box) == INSIDE && oldOctant->FitBoundingBox(box, boxSize))
continue;
// Begin reinsert process. Start from root and check what level child needs to be used
Octant* newOctant = &root;
Vector3 boxCenter = box.Center();
for (;;)
{
bool insertHere;
// If node does not fit fully inside root octant, must remain in it
if (newOctant == &root)
insertHere = newOctant->cullingBox.IsInside(box) != INSIDE || newOctant->FitBoundingBox(box, boxSize);
else
insertHere = newOctant->FitBoundingBox(box, boxSize);
if (insertHere)
{
if (newOctant != oldOctant)
{
// Add first, then remove, because node count going to zero deletes the octree branch in question
AddNode(node, newOctant);
if (oldOctant)
RemoveNode(node, oldOctant);
}
break;
}
else
newOctant = CreateChildOctant(newOctant, newOctant->ChildIndex(boxCenter));
}
}
}
updateQueue.Clear();
}
void Octree::RemoveNode(OctreeNode* node, Octant* octant)
{
// Do not set the node's octant pointer to zero, as the node may already be added into another octant
octant->nodes.Remove(node);
// Decrement the node count in the whole parent branch and erase empty octants as necessary
while (octant)
{
--octant->numNodes;
Octant* next = octant->parent;
if (!octant->numNodes && next)
DeleteChildOctant(next, next->ChildIndex(octant->center));
octant = next;
}
}