690e07b509
Complete rewrite of spatial partitioning using a bounding volume hierarchy rather than octree. Switchable in project settings between using octree or BVH for rendering and physics.
221 lines
6.1 KiB
C++
221 lines
6.1 KiB
C++
|
|
// for slow incremental optimization, we will periodically remove each
|
|
// item from the tree and reinsert, to give it a chance to find a better position
|
|
void _logic_item_remove_and_reinsert(uint32_t p_ref_id) {
|
|
// get the reference
|
|
ItemRef &ref = _refs[p_ref_id];
|
|
|
|
// special case of debug draw
|
|
if (ref.item_id == BVHCommon::INVALID)
|
|
return;
|
|
|
|
BVH_ASSERT(ref.tnode_id != BVHCommon::INVALID);
|
|
|
|
// some overlay elaborate way to find out which tree the node is in!
|
|
BVHHandle temp_handle;
|
|
temp_handle.set_id(p_ref_id);
|
|
_current_tree = _handle_get_tree_id(temp_handle);
|
|
|
|
// remove and reinsert
|
|
BVH_ABB abb;
|
|
node_remove_item(p_ref_id, &abb);
|
|
|
|
// we must choose where to add to tree
|
|
ref.tnode_id = _logic_choose_item_add_node(_root_node_id[_current_tree], abb);
|
|
_node_add_item(ref.tnode_id, p_ref_id, abb);
|
|
|
|
refit_upward_and_balance(ref.tnode_id);
|
|
}
|
|
|
|
// from randy gaul balance function
|
|
BVH_ABB _logic_abb_merge(const BVH_ABB &a, const BVH_ABB &b) {
|
|
BVH_ABB c = a;
|
|
c.merge(b);
|
|
return c;
|
|
}
|
|
|
|
//--------------------------------------------------------------------------------------------------
|
|
/**
|
|
@file q3DynamicAABBTree.h
|
|
@author Randy Gaul
|
|
@date 10/10/2014
|
|
Copyright (c) 2014 Randy Gaul http://www.randygaul.net
|
|
This software is provided 'as-is', without any express or implied
|
|
warranty. In no event will the authors be held liable for any damages
|
|
arising from the use of this software.
|
|
Permission is granted to anyone to use this software for any purpose,
|
|
including commercial applications, and to alter it and redistribute it
|
|
freely, subject to the following restrictions:
|
|
1. The origin of this software must not be misrepresented; you must not
|
|
claim that you wrote the original software. If you use this software
|
|
in a product, an acknowledgment in the product documentation would be
|
|
appreciated but is not required.
|
|
2. Altered source versions must be plainly marked as such, and must not
|
|
be misrepresented as being the original software.
|
|
3. This notice may not be removed or altered from any source distribution.
|
|
*/
|
|
//--------------------------------------------------------------------------------------------------
|
|
|
|
// This function is based on the 'Balance' function from Randy Gaul's qu3e
|
|
// https://github.com/RandyGaul/qu3e
|
|
// It is MODIFIED from qu3e version.
|
|
// This is the only function used (and _logic_abb_merge helper function).
|
|
int32_t _logic_balance(int32_t iA) {
|
|
// return iA; // uncomment this to bypass balance
|
|
|
|
TNode *A = &_nodes[iA];
|
|
|
|
if (A->is_leaf() || A->height == 1)
|
|
return iA;
|
|
|
|
/* A
|
|
/ \
|
|
B C
|
|
/ \ / \
|
|
D E F G
|
|
*/
|
|
|
|
CRASH_COND(A->num_children != 2);
|
|
int32_t iB = A->children[0];
|
|
int32_t iC = A->children[1];
|
|
TNode *B = &_nodes[iB];
|
|
TNode *C = &_nodes[iC];
|
|
|
|
int32_t balance = C->height - B->height;
|
|
|
|
// C is higher, promote C
|
|
if (balance > 1) {
|
|
int32_t iF = C->children[0];
|
|
int32_t iG = C->children[1];
|
|
TNode *F = &_nodes[iF];
|
|
TNode *G = &_nodes[iG];
|
|
|
|
// grandParent point to C
|
|
if (A->parent_id != BVHCommon::INVALID) {
|
|
if (_nodes[A->parent_id].children[0] == iA)
|
|
_nodes[A->parent_id].children[0] = iC;
|
|
|
|
else
|
|
_nodes[A->parent_id].children[1] = iC;
|
|
} else {
|
|
// check this .. seems dodgy
|
|
change_root_node(iC);
|
|
}
|
|
|
|
// Swap A and C
|
|
C->children[0] = iA;
|
|
C->parent_id = A->parent_id;
|
|
A->parent_id = iC;
|
|
|
|
// Finish rotation
|
|
if (F->height > G->height) {
|
|
C->children[1] = iF;
|
|
A->children[1] = iG;
|
|
G->parent_id = iA;
|
|
A->aabb = _logic_abb_merge(B->aabb, G->aabb);
|
|
C->aabb = _logic_abb_merge(A->aabb, F->aabb);
|
|
|
|
A->height = 1 + MAX(B->height, G->height);
|
|
C->height = 1 + MAX(A->height, F->height);
|
|
}
|
|
|
|
else {
|
|
C->children[1] = iG;
|
|
A->children[1] = iF;
|
|
F->parent_id = iA;
|
|
A->aabb = _logic_abb_merge(B->aabb, F->aabb);
|
|
C->aabb = _logic_abb_merge(A->aabb, G->aabb);
|
|
|
|
A->height = 1 + MAX(B->height, F->height);
|
|
C->height = 1 + MAX(A->height, G->height);
|
|
}
|
|
|
|
return iC;
|
|
}
|
|
|
|
// B is higher, promote B
|
|
else if (balance < -1) {
|
|
int32_t iD = B->children[0];
|
|
int32_t iE = B->children[1];
|
|
TNode *D = &_nodes[iD];
|
|
TNode *E = &_nodes[iE];
|
|
|
|
// grandParent point to B
|
|
if (A->parent_id != BVHCommon::INVALID) {
|
|
if (_nodes[A->parent_id].children[0] == iA)
|
|
_nodes[A->parent_id].children[0] = iB;
|
|
else
|
|
_nodes[A->parent_id].children[1] = iB;
|
|
}
|
|
|
|
else {
|
|
// check this .. seems dodgy
|
|
change_root_node(iB);
|
|
}
|
|
|
|
// Swap A and B
|
|
B->children[1] = iA;
|
|
B->parent_id = A->parent_id;
|
|
A->parent_id = iB;
|
|
|
|
// Finish rotation
|
|
if (D->height > E->height) {
|
|
B->children[0] = iD;
|
|
A->children[0] = iE;
|
|
E->parent_id = iA;
|
|
A->aabb = _logic_abb_merge(C->aabb, E->aabb);
|
|
B->aabb = _logic_abb_merge(A->aabb, D->aabb);
|
|
|
|
A->height = 1 + MAX(C->height, E->height);
|
|
B->height = 1 + MAX(A->height, D->height);
|
|
}
|
|
|
|
else {
|
|
B->children[0] = iE;
|
|
A->children[0] = iD;
|
|
D->parent_id = iA;
|
|
A->aabb = _logic_abb_merge(C->aabb, D->aabb);
|
|
B->aabb = _logic_abb_merge(A->aabb, E->aabb);
|
|
|
|
A->height = 1 + MAX(C->height, D->height);
|
|
B->height = 1 + MAX(A->height, E->height);
|
|
}
|
|
|
|
return iB;
|
|
}
|
|
|
|
return iA;
|
|
}
|
|
|
|
// either choose an existing node to add item to, or create a new node and return this
|
|
uint32_t _logic_choose_item_add_node(uint32_t p_node_id, const BVH_ABB &p_aabb) {
|
|
|
|
while (true) {
|
|
BVH_ASSERT(p_node_id != BVHCommon::INVALID);
|
|
TNode &tnode = _nodes[p_node_id];
|
|
|
|
if (tnode.is_leaf()) {
|
|
// if a leaf, and non full, use this to add to
|
|
if (!node_is_leaf_full(tnode))
|
|
return p_node_id;
|
|
|
|
// else split the leaf, and use one of the children to add to
|
|
return split_leaf(p_node_id, p_aabb);
|
|
}
|
|
|
|
// this should not happen???
|
|
// is still happening, need to debug and find circumstances. Is not that serious
|
|
// but would be nice to prevent. I think it only happens with the root node.
|
|
if (tnode.num_children == 1) {
|
|
WARN_PRINT_ONCE("BVH::recursive_choose_item_add_node, node with 1 child, recovering");
|
|
p_node_id = tnode.children[0];
|
|
} else {
|
|
BVH_ASSERT(tnode.num_children == 2);
|
|
TNode &childA = _nodes[tnode.children[0]];
|
|
TNode &childB = _nodes[tnode.children[1]];
|
|
int which = p_aabb.select_by_proximity(childA.aabb, childB.aabb);
|
|
|
|
p_node_id = tnode.children[which];
|
|
}
|
|
}
|
|
}
|