Program Listing for File hierarchy_tree-inl.h
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#ifndef HPP_FCL_HIERARCHY_TREE_INL_H
#define HPP_FCL_HIERARCHY_TREE_INL_H
#include "hpp/fcl/broadphase/detail/hierarchy_tree.h"
namespace hpp {
namespace fcl {
namespace detail {
//==============================================================================
template <typename BV>
HierarchyTree<BV>::HierarchyTree(int bu_threshold_, int topdown_level_) {
root_node = nullptr;
n_leaves = 0;
free_node = nullptr;
max_lookahead_level = -1;
opath = 0;
bu_threshold = bu_threshold_;
topdown_level = topdown_level_;
}
//==============================================================================
template <typename BV>
HierarchyTree<BV>::~HierarchyTree() {
clear();
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::init(std::vector<Node*>& leaves, int level) {
switch (level) {
case 0:
init_0(leaves);
break;
case 1:
init_1(leaves);
break;
case 2:
init_2(leaves);
break;
case 3:
init_3(leaves);
break;
default:
init_0(leaves);
}
}
//==============================================================================
template <typename BV>
typename HierarchyTree<BV>::Node* HierarchyTree<BV>::insert(const BV& bv,
void* data) {
Node* leaf = createNode(nullptr, bv, data);
insertLeaf(root_node, leaf);
++n_leaves;
return leaf;
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::remove(Node* leaf) {
removeLeaf(leaf);
deleteNode(leaf);
--n_leaves;
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::clear() {
if (root_node) recurseDeleteNode(root_node);
n_leaves = 0;
delete free_node;
free_node = nullptr;
max_lookahead_level = -1;
opath = 0;
}
//==============================================================================
template <typename BV>
bool HierarchyTree<BV>::empty() const {
return (nullptr == root_node);
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::update(Node* leaf, int lookahead_level) {
// TODO(DamrongGuoy): Since we update a leaf node by removing and
// inserting the same leaf node, it is likely to change the structure of
// the tree even if no object's pose has changed. In the future,
// find a way to preserve the structure of the tree to solve this issue:
// https://github.com/flexible-collision-library/fcl/issues/368
// First we remove the leaf node pointed by `leaf` variable from the tree.
// The `sub_root` variable is the root of the subtree containing nodes
// whose BVs were adjusted due to node removal.
typename HierarchyTree<BV>::Node* sub_root = removeLeaf(leaf);
if (sub_root) {
if (lookahead_level > 0) {
// For positive `lookahead_level`, we move the `sub_root` variable up.
for (int i = 0; (i < lookahead_level) && sub_root->parent; ++i)
sub_root = sub_root->parent;
} else
// By default, lookahead_level = -1, and we reset the `sub_root` variable
// to the root of the entire tree.
sub_root = root_node;
}
// Then we insert the node pointed by `leaf` variable back into the
// subtree rooted at `sub_root` variable.
insertLeaf(sub_root, leaf);
}
//==============================================================================
template <typename BV>
bool HierarchyTree<BV>::update(Node* leaf, const BV& bv) {
if (leaf->bv.contain(bv)) return false;
update_(leaf, bv);
return true;
}
//==============================================================================
template <typename S, typename BV>
struct UpdateImpl {
static bool run(const HierarchyTree<BV>& tree,
typename HierarchyTree<BV>::Node* leaf, const BV& bv,
const Vec3f& /*vel*/, FCL_REAL /*margin*/) {
if (leaf->bv.contain(bv)) return false;
tree.update_(leaf, bv);
return true;
}
static bool run(const HierarchyTree<BV>& tree,
typename HierarchyTree<BV>::Node* leaf, const BV& bv,
const Vec3f& /*vel*/) {
if (leaf->bv.contain(bv)) return false;
tree.update_(leaf, bv);
return true;
}
};
//==============================================================================
template <typename BV>
bool HierarchyTree<BV>::update(Node* leaf, const BV& bv, const Vec3f& vel,
FCL_REAL margin) {
return UpdateImpl<FCL_REAL, BV>::run(*this, leaf, bv, vel, margin);
}
//==============================================================================
template <typename BV>
bool HierarchyTree<BV>::update(Node* leaf, const BV& bv, const Vec3f& vel) {
return UpdateImpl<FCL_REAL, BV>::run(*this, leaf, bv, vel);
}
//==============================================================================
template <typename BV>
size_t HierarchyTree<BV>::getMaxHeight() const {
if (!root_node) return 0;
return getMaxHeight(root_node);
}
//==============================================================================
template <typename BV>
size_t HierarchyTree<BV>::getMaxDepth() const {
if (!root_node) return 0;
size_t max_depth;
getMaxDepth(root_node, 0, max_depth);
return max_depth;
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::balanceBottomup() {
if (root_node) {
std::vector<Node*> leaves;
leaves.reserve(n_leaves);
fetchLeaves(root_node, leaves);
bottomup(leaves.begin(), leaves.end());
root_node = leaves[0];
}
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::balanceTopdown() {
if (root_node) {
std::vector<Node*> leaves;
leaves.reserve(n_leaves);
fetchLeaves(root_node, leaves);
root_node = topdown(leaves.begin(), leaves.end());
}
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::balanceIncremental(int iterations) {
if (iterations < 0) iterations = (int)n_leaves;
if (root_node && (iterations > 0)) {
for (int i = 0; i < iterations; ++i) {
Node* node = root_node;
unsigned int bit = 0;
while (!node->isLeaf()) {
node = sort(node, root_node)->children[(opath >> bit) & 1];
bit = (bit + 1) & (sizeof(unsigned int) * 8 - 1);
}
update(node);
++opath;
}
}
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::refit() {
if (root_node) recurseRefit(root_node);
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::extractLeaves(const Node* root,
std::vector<Node*>& leaves) const {
if (!root->isLeaf()) {
extractLeaves(root->children[0], leaves);
extractLeaves(root->children[1], leaves);
} else
leaves.push_back(root);
}
//==============================================================================
template <typename BV>
size_t HierarchyTree<BV>::size() const {
return n_leaves;
}
//==============================================================================
template <typename BV>
typename HierarchyTree<BV>::Node* HierarchyTree<BV>::getRoot() const {
return root_node;
}
//==============================================================================
template <typename BV>
typename HierarchyTree<BV>::Node*& HierarchyTree<BV>::getRoot() {
return root_node;
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::print(Node* root, int depth) {
for (int i = 0; i < depth; ++i) std::cout << " ";
std::cout << " (" << root->bv.min_[0] << ", " << root->bv.min_[1] << ", "
<< root->bv.min_[2] << "; " << root->bv.max_[0] << ", "
<< root->bv.max_[1] << ", " << root->bv.max_[2] << ")" << std::endl;
if (root->isLeaf()) {
} else {
print(root->children[0], depth + 1);
print(root->children[1], depth + 1);
}
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::bottomup(const NodeVecIterator lbeg,
const NodeVecIterator lend) {
NodeVecIterator lcur_end = lend;
while (lbeg < lcur_end - 1) {
NodeVecIterator min_it1 = lbeg;
NodeVecIterator min_it2 = lbeg + 1;
FCL_REAL min_size = (std::numeric_limits<FCL_REAL>::max)();
for (NodeVecIterator it1 = lbeg; it1 < lcur_end; ++it1) {
for (NodeVecIterator it2 = it1 + 1; it2 < lcur_end; ++it2) {
FCL_REAL cur_size = ((*it1)->bv + (*it2)->bv).size();
if (cur_size < min_size) {
min_size = cur_size;
min_it1 = it1;
min_it2 = it2;
}
}
}
Node* n[2] = {*min_it1, *min_it2};
Node* p = createNode(nullptr, n[0]->bv, n[1]->bv, nullptr);
p->children[0] = n[0];
p->children[1] = n[1];
n[0]->parent = p;
n[1]->parent = p;
*min_it1 = p;
Node* tmp = *min_it2;
lcur_end--;
*min_it2 = *lcur_end;
*lcur_end = tmp;
}
}
//==============================================================================
template <typename BV>
typename HierarchyTree<BV>::Node* HierarchyTree<BV>::topdown(
const NodeVecIterator lbeg, const NodeVecIterator lend) {
switch (topdown_level) {
case 0:
return topdown_0(lbeg, lend);
break;
case 1:
return topdown_1(lbeg, lend);
break;
default:
return topdown_0(lbeg, lend);
}
}
//==============================================================================
template <typename BV>
size_t HierarchyTree<BV>::getMaxHeight(Node* node) const {
if (!node->isLeaf()) {
size_t height1 = getMaxHeight(node->children[0]);
size_t height2 = getMaxHeight(node->children[1]);
return std::max(height1, height2) + 1;
} else
return 0;
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::getMaxDepth(Node* node, size_t depth,
size_t& max_depth) const {
if (!node->isLeaf()) {
getMaxDepth(node->children[0], depth + 1, max_depth);
getMaxDepth(node->children[1], depth + 1, max_depth);
} else
max_depth = std::max(max_depth, depth);
}
//==============================================================================
template <typename BV>
typename HierarchyTree<BV>::Node* HierarchyTree<BV>::topdown_0(
const NodeVecIterator lbeg, const NodeVecIterator lend) {
long num_leaves = lend - lbeg;
if (num_leaves > 1) {
if (num_leaves > bu_threshold) {
BV vol = (*lbeg)->bv;
for (NodeVecIterator it = lbeg + 1; it < lend; ++it) vol += (*it)->bv;
int best_axis = 0;
FCL_REAL extent[3] = {vol.width(), vol.height(), vol.depth()};
if (extent[1] > extent[0]) best_axis = 1;
if (extent[2] > extent[best_axis]) best_axis = 2;
// compute median
NodeVecIterator lcenter = lbeg + num_leaves / 2;
std::nth_element(lbeg, lcenter, lend,
std::bind(&nodeBaseLess<BV>, std::placeholders::_1,
std::placeholders::_2, std::ref(best_axis)));
Node* node = createNode(nullptr, vol, nullptr);
node->children[0] = topdown_0(lbeg, lcenter);
node->children[1] = topdown_0(lcenter, lend);
node->children[0]->parent = node;
node->children[1]->parent = node;
return node;
} else {
bottomup(lbeg, lend);
return *lbeg;
}
}
return *lbeg;
}
//==============================================================================
template <typename BV>
typename HierarchyTree<BV>::Node* HierarchyTree<BV>::topdown_1(
const NodeVecIterator lbeg, const NodeVecIterator lend) {
long num_leaves = lend - lbeg;
if (num_leaves > 1) {
if (num_leaves > bu_threshold) {
Vec3f split_p = (*lbeg)->bv.center();
BV vol = (*lbeg)->bv;
NodeVecIterator it;
for (it = lbeg + 1; it < lend; ++it) {
split_p += (*it)->bv.center();
vol += (*it)->bv;
}
split_p /= static_cast<FCL_REAL>(num_leaves);
int best_axis = -1;
long bestmidp = num_leaves;
int splitcount[3][2] = {{0, 0}, {0, 0}, {0, 0}};
for (it = lbeg; it < lend; ++it) {
Vec3f x = (*it)->bv.center() - split_p;
for (int j = 0; j < 3; ++j) ++splitcount[j][x[j] > 0 ? 1 : 0];
}
for (int i = 0; i < 3; ++i) {
if ((splitcount[i][0] > 0) && (splitcount[i][1] > 0)) {
long midp = std::abs(splitcount[i][0] - splitcount[i][1]);
if (midp < bestmidp) {
best_axis = i;
bestmidp = midp;
}
}
}
if (best_axis < 0) best_axis = 0;
FCL_REAL split_value = split_p[best_axis];
NodeVecIterator lcenter = lbeg;
for (it = lbeg; it < lend; ++it) {
if ((*it)->bv.center()[best_axis] < split_value) {
Node* temp = *it;
*it = *lcenter;
*lcenter = temp;
++lcenter;
}
}
Node* node = createNode(nullptr, vol, nullptr);
node->children[0] = topdown_1(lbeg, lcenter);
node->children[1] = topdown_1(lcenter, lend);
node->children[0]->parent = node;
node->children[1]->parent = node;
return node;
} else {
bottomup(lbeg, lend);
return *lbeg;
}
}
return *lbeg;
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::init_0(std::vector<Node*>& leaves) {
clear();
root_node = topdown(leaves.begin(), leaves.end());
n_leaves = leaves.size();
max_lookahead_level = -1;
opath = 0;
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::init_1(std::vector<Node*>& leaves) {
clear();
BV bound_bv;
if (leaves.size() > 0) bound_bv = leaves[0]->bv;
for (size_t i = 1; i < leaves.size(); ++i) bound_bv += leaves[i]->bv;
morton_functor<FCL_REAL, uint32_t> coder(bound_bv);
for (size_t i = 0; i < leaves.size(); ++i)
leaves[i]->code = coder(leaves[i]->bv.center());
std::sort(leaves.begin(), leaves.end(), SortByMorton());
root_node = mortonRecurse_0(leaves.begin(), leaves.end(),
(1 << (coder.bits() - 1)), coder.bits() - 1);
refit();
n_leaves = leaves.size();
max_lookahead_level = -1;
opath = 0;
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::init_2(std::vector<Node*>& leaves) {
clear();
BV bound_bv;
if (leaves.size() > 0) bound_bv = leaves[0]->bv;
for (size_t i = 1; i < leaves.size(); ++i) bound_bv += leaves[i]->bv;
morton_functor<FCL_REAL, uint32_t> coder(bound_bv);
for (size_t i = 0; i < leaves.size(); ++i)
leaves[i]->code = coder(leaves[i]->bv.center());
std::sort(leaves.begin(), leaves.end(), SortByMorton());
root_node = mortonRecurse_1(leaves.begin(), leaves.end(),
(1 << (coder.bits() - 1)), coder.bits() - 1);
refit();
n_leaves = leaves.size();
max_lookahead_level = -1;
opath = 0;
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::init_3(std::vector<Node*>& leaves) {
clear();
BV bound_bv;
if (leaves.size() > 0) bound_bv = leaves[0]->bv;
for (size_t i = 1; i < leaves.size(); ++i) bound_bv += leaves[i]->bv;
morton_functor<FCL_REAL, uint32_t> coder(bound_bv);
for (size_t i = 0; i < leaves.size(); ++i)
leaves[i]->code = coder(leaves[i]->bv.center());
std::sort(leaves.begin(), leaves.end(), SortByMorton());
root_node = mortonRecurse_2(leaves.begin(), leaves.end());
refit();
n_leaves = leaves.size();
max_lookahead_level = -1;
opath = 0;
}
//==============================================================================
template <typename BV>
typename HierarchyTree<BV>::Node* HierarchyTree<BV>::mortonRecurse_0(
const NodeVecIterator lbeg, const NodeVecIterator lend,
const uint32_t& split, int bits) {
long num_leaves = lend - lbeg;
if (num_leaves > 1) {
if (bits > 0) {
Node dummy;
dummy.code = split;
NodeVecIterator lcenter =
std::lower_bound(lbeg, lend, &dummy, SortByMorton());
if (lcenter == lbeg) {
uint32_t split2 = split | (1 << (bits - 1));
return mortonRecurse_0(lbeg, lend, split2, bits - 1);
} else if (lcenter == lend) {
uint32_t split1 = (split & (~(1 << bits))) | (1 << (bits - 1));
return mortonRecurse_0(lbeg, lend, split1, bits - 1);
} else {
uint32_t split1 = (split & (~(1 << bits))) | (1 << (bits - 1));
uint32_t split2 = split | (1 << (bits - 1));
Node* child1 = mortonRecurse_0(lbeg, lcenter, split1, bits - 1);
Node* child2 = mortonRecurse_0(lcenter, lend, split2, bits - 1);
Node* node = createNode(nullptr, nullptr);
node->children[0] = child1;
node->children[1] = child2;
child1->parent = node;
child2->parent = node;
return node;
}
} else {
Node* node = topdown(lbeg, lend);
return node;
}
} else
return *lbeg;
}
//==============================================================================
template <typename BV>
typename HierarchyTree<BV>::Node* HierarchyTree<BV>::mortonRecurse_1(
const NodeVecIterator lbeg, const NodeVecIterator lend,
const uint32_t& split, int bits) {
long num_leaves = lend - lbeg;
if (num_leaves > 1) {
if (bits > 0) {
Node dummy;
dummy.code = split;
NodeVecIterator lcenter =
std::lower_bound(lbeg, lend, &dummy, SortByMorton());
if (lcenter == lbeg) {
uint32_t split2 = split | (1 << (bits - 1));
return mortonRecurse_1(lbeg, lend, split2, bits - 1);
} else if (lcenter == lend) {
uint32_t split1 = (split & (~(1 << bits))) | (1 << (bits - 1));
return mortonRecurse_1(lbeg, lend, split1, bits - 1);
} else {
uint32_t split1 = (split & (~(1 << bits))) | (1 << (bits - 1));
uint32_t split2 = split | (1 << (bits - 1));
Node* child1 = mortonRecurse_1(lbeg, lcenter, split1, bits - 1);
Node* child2 = mortonRecurse_1(lcenter, lend, split2, bits - 1);
Node* node = createNode(nullptr, nullptr);
node->children[0] = child1;
node->children[1] = child2;
child1->parent = node;
child2->parent = node;
return node;
}
} else {
Node* child1 = mortonRecurse_1(lbeg, lbeg + num_leaves / 2, 0, bits - 1);
Node* child2 = mortonRecurse_1(lbeg + num_leaves / 2, lend, 0, bits - 1);
Node* node = createNode(nullptr, nullptr);
node->children[0] = child1;
node->children[1] = child2;
child1->parent = node;
child2->parent = node;
return node;
}
} else
return *lbeg;
}
//==============================================================================
template <typename BV>
typename HierarchyTree<BV>::Node* HierarchyTree<BV>::mortonRecurse_2(
const NodeVecIterator lbeg, const NodeVecIterator lend) {
long num_leaves = lend - lbeg;
if (num_leaves > 1) {
Node* child1 = mortonRecurse_2(lbeg, lbeg + num_leaves / 2);
Node* child2 = mortonRecurse_2(lbeg + num_leaves / 2, lend);
Node* node = createNode(nullptr, nullptr);
node->children[0] = child1;
node->children[1] = child2;
child1->parent = node;
child2->parent = node;
return node;
} else
return *lbeg;
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::update_(Node* leaf, const BV& bv) {
Node* root = removeLeaf(leaf);
if (root) {
if (max_lookahead_level >= 0) {
for (int i = 0; (i < max_lookahead_level) && root->parent; ++i)
root = root->parent;
} else
root = root_node;
}
leaf->bv = bv;
insertLeaf(root, leaf);
}
//==============================================================================
template <typename BV>
typename HierarchyTree<BV>::Node* HierarchyTree<BV>::sort(Node* n, Node*& r) {
Node* p = n->parent;
if (p > n) {
size_t i = indexOf(n);
size_t j = 1 - i;
Node* s = p->children[j];
Node* q = p->parent;
if (q)
q->children[indexOf(p)] = n;
else
r = n;
s->parent = n;
p->parent = n;
n->parent = q;
p->children[0] = n->children[0];
p->children[1] = n->children[1];
n->children[0]->parent = p;
n->children[1]->parent = p;
n->children[i] = p;
n->children[j] = s;
std::swap(p->bv, n->bv);
return p;
}
return n;
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::insertLeaf(Node* const sub_root, Node* const leaf)
// Attempts to insert `leaf` into a subtree rooted at `sub_root`.
// 1. If the whole tree is empty, then `leaf` simply becomes the tree.
// 2. Otherwise, a leaf node called `sibling` of the subtree rooted at
// `sub_root` is selected (the selection criteria is a black box for this
// algorithm), and the `sibling` leaf is replaced by an internal node with
// two children, `sibling` and `leaf`. The bounding volumes are updated as
// necessary.
{
if (!root_node) {
// If the entire tree is empty, the node pointed by `leaf` variable will
// become the root of the tree.
root_node = leaf;
leaf->parent = nullptr;
return;
}
// Traverse the tree from the given `sub_root` down to an existing leaf
// node that we call `sibling`. The `sibling` node will eventually become
// the sibling of the given `leaf` node.
Node* sibling = sub_root;
while (!sibling->isLeaf()) {
sibling = sibling->children[select(*leaf, *(sibling->children[0]),
*(sibling->children[1]))];
}
Node* prev = sibling->parent;
// Create a new `node` that later will become the new parent of both the
// `sibling` and the given `leaf`.
Node* node = createNode(prev, leaf->bv, sibling->bv, nullptr);
if (prev)
// If the parent `prev` of the `sibling` is an interior node, we will
// replace the `sibling` with the subtree {node {`sibling`, leaf}} like
// this:
// Before After
//
// ╱ ╱
// prev prev
// ╱ ╲ ─> ╱ ╲
// sibling ... node ...
// ╱ ╲
// sibling leaf
{
prev->children[indexOf(sibling)] = node;
node->children[0] = sibling;
sibling->parent = node;
node->children[1] = leaf;
leaf->parent = node;
// Now that we've inserted `leaf` some of the existing bounding
// volumes might not fully enclose their children. Walk up the tree
// looking for parents that don't already enclose their children
// and create a new tight-fitting bounding volume for those.
do {
if (!prev->bv.contain(node->bv))
prev->bv = prev->children[0]->bv + prev->children[1]->bv;
else
break;
node = prev;
} while (nullptr != (prev = node->parent));
} else
// If the `sibling` has no parent, i.e., the tree is a singleton,
// we will replace it with the 3-node tree {node {`sibling`, `leaf`}} like
// this:
//
// node
// ╱ ╲
// sibling leaf
{
node->children[0] = sibling;
sibling->parent = node;
node->children[1] = leaf;
leaf->parent = node;
root_node = node;
}
// Note that the above algorithm always adds the new `leaf` node as the right
// child, i.e., children[1]. Calling removeLeaf(l) followed by calling
// this function insertLeaf(l) where l is a left child will result in
// switching l and its sibling even if no object's pose has changed.
}
//==============================================================================
template <typename BV>
typename HierarchyTree<BV>::Node* HierarchyTree<BV>::removeLeaf(
Node* const leaf) {
// Deletes `leaf` by replacing the subtree consisting of `leaf`, its sibling,
// and its parent with just its sibling. It then "tightens" the ancestor
// bounding volumes. Returns a pointer to the parent of the highest node whose
// BV changed due to the removal.
if (leaf == root_node) {
// If the `leaf` node is the only node in the tree, the tree becomes empty.
root_node = nullptr;
return nullptr;
}
Node* parent = leaf->parent;
Node* prev = parent->parent;
Node* sibling = parent->children[1 - indexOf(leaf)];
if (prev) {
// If the parent node is not the root node, the sibling node will
// replace the parent node like this:
//
// Before After
// ... ...
// ╱ ╱
// prev prev
// ╱ ╲ ╱ ╲
// parent ... ─> sibling ...
// ╱ ╲ ╱╲
// leaf sibling ...
// ╱╲
// ...
//
// Step 1: replace the subtree {parent {leaf, sibling {...}}} with
// {sibling {...}}.
prev->children[indexOf(parent)] = sibling;
sibling->parent = prev;
deleteNode(parent);
// Step 2: tighten up the BVs of the ancestor nodes.
while (prev) {
BV new_bv = prev->children[0]->bv + prev->children[1]->bv;
if (!(new_bv == prev->bv)) {
prev->bv = new_bv;
prev = prev->parent;
} else
break;
}
return prev ? prev : root_node;
} else {
// If the parent node is the root node, the sibling node will become the
// root of the whole tree like this:
//
// Before After
//
// parent
// ╱ ╲
// leaf sibling ─> sibling
// ╱╲ ╱╲
// ... ...
root_node = sibling;
sibling->parent = nullptr;
deleteNode(parent);
return root_node;
}
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::fetchLeaves(Node* root, std::vector<Node*>& leaves,
int depth) {
if ((!root->isLeaf()) && depth) {
fetchLeaves(root->children[0], leaves, depth - 1);
fetchLeaves(root->children[1], leaves, depth - 1);
deleteNode(root);
} else {
leaves.push_back(root);
}
}
//==============================================================================
template <typename BV>
size_t HierarchyTree<BV>::indexOf(Node* node) {
// node cannot be nullptr
return (node->parent->children[1] == node);
}
//==============================================================================
template <typename BV>
typename HierarchyTree<BV>::Node* HierarchyTree<BV>::createNode(Node* parent,
const BV& bv,
void* data) {
Node* node = createNode(parent, data);
node->bv = bv;
return node;
}
//==============================================================================
template <typename BV>
typename HierarchyTree<BV>::Node* HierarchyTree<BV>::createNode(Node* parent,
const BV& bv1,
const BV& bv2,
void* data) {
Node* node = createNode(parent, data);
node->bv = bv1 + bv2;
return node;
}
//==============================================================================
template <typename BV>
typename HierarchyTree<BV>::Node* HierarchyTree<BV>::createNode(Node* parent,
void* data) {
Node* node = nullptr;
if (free_node) {
node = free_node;
free_node = nullptr;
} else
node = new Node();
node->parent = parent;
node->data = data;
node->children[1] = 0;
return node;
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::deleteNode(Node* node) {
if (free_node != node) {
delete free_node;
free_node = node;
}
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::recurseDeleteNode(Node* node) {
if (!node->isLeaf()) {
recurseDeleteNode(node->children[0]);
recurseDeleteNode(node->children[1]);
}
if (node == root_node) root_node = nullptr;
deleteNode(node);
}
//==============================================================================
template <typename BV>
void HierarchyTree<BV>::recurseRefit(Node* node) {
if (!node->isLeaf()) {
recurseRefit(node->children[0]);
recurseRefit(node->children[1]);
node->bv = node->children[0]->bv + node->children[1]->bv;
} else
return;
}
//==============================================================================
template <typename BV>
bool nodeBaseLess(NodeBase<BV>* a, NodeBase<BV>* b, int d) {
if (a->bv.center()[d] < b->bv.center()[d]) return true;
return false;
}
//==============================================================================
template <typename S, typename BV>
struct SelectImpl {
static std::size_t run(const NodeBase<BV>& /*query*/,
const NodeBase<BV>& /*node1*/,
const NodeBase<BV>& /*node2*/) {
return 0;
}
static std::size_t run(const BV& /*query*/, const NodeBase<BV>& /*node1*/,
const NodeBase<BV>& /*node2*/) {
return 0;
}
};
//==============================================================================
template <typename BV>
size_t select(const NodeBase<BV>& query, const NodeBase<BV>& node1,
const NodeBase<BV>& node2) {
return SelectImpl<FCL_REAL, BV>::run(query, node1, node2);
}
//==============================================================================
template <typename BV>
size_t select(const BV& query, const NodeBase<BV>& node1,
const NodeBase<BV>& node2) {
return SelectImpl<FCL_REAL, BV>::run(query, node1, node2);
}
//==============================================================================
template <typename S>
struct SelectImpl<S, AABB> {
static std::size_t run(const NodeBase<AABB>& node,
const NodeBase<AABB>& node1,
const NodeBase<AABB>& node2) {
const AABB& bv = node.bv;
const AABB& bv1 = node1.bv;
const AABB& bv2 = node2.bv;
Vec3f v = bv.min_ + bv.max_;
Vec3f v1 = v - (bv1.min_ + bv1.max_);
Vec3f v2 = v - (bv2.min_ + bv2.max_);
FCL_REAL d1 = fabs(v1[0]) + fabs(v1[1]) + fabs(v1[2]);
FCL_REAL d2 = fabs(v2[0]) + fabs(v2[1]) + fabs(v2[2]);
return (d1 < d2) ? 0 : 1;
}
static std::size_t run(const AABB& query, const NodeBase<AABB>& node1,
const NodeBase<AABB>& node2) {
const AABB& bv = query;
const AABB& bv1 = node1.bv;
const AABB& bv2 = node2.bv;
Vec3f v = bv.min_ + bv.max_;
Vec3f v1 = v - (bv1.min_ + bv1.max_);
Vec3f v2 = v - (bv2.min_ + bv2.max_);
FCL_REAL d1 = fabs(v1[0]) + fabs(v1[1]) + fabs(v1[2]);
FCL_REAL d2 = fabs(v2[0]) + fabs(v2[1]) + fabs(v2[2]);
return (d1 < d2) ? 0 : 1;
}
};
} // namespace detail
} // namespace fcl
} // namespace hpp
#endif