} // end spread();
/// search kd-tree starting at *node, looking for overlap with bb, and placing
/// found objects in *tris
protected void search_node(LinkedList <Triangle> tris, Bbox bb, KDNode <Triangle> node)
{
if (node.isLeaf)
{ // we found a bucket node, so add all triangles and return.
foreach (Triangle t in node.tris)
{
tris.AddLast(t);
}
//std::cout << " search_node Leaf bucket tris-size() = " << tris->size() << "\n";
return; // end recursion
}
else if ((node.dim % 2) == 0)
{ // cutting along a min-direction: 0, 2, 4
// not a bucket node, so recursevily search hi/lo branches of KDNode
uint maxdim = (uint)(node.dim + 1);
if (node.cutval > bb[maxdim])
{ // search only lo
search_node(tris, bb, node.lo);
}
else
{ // need to search both child nodes
if (node.hi != null)
{
search_node(tris, bb, node.hi);
}
if (node.lo != null)
{
search_node(tris, bb, node.lo);
}
}
}
else
{ // cutting along a max-dimension: 1,3,5
uint mindim = (uint)(node.dim - 1);
if (node.cutval < bb[mindim])
{ // search only hi
search_node(tris, bb, node.hi);
}
else
{ // need to search both child nodes
if (node.hi != null)
{
search_node(tris, bb, node.hi);
}
if (node.lo != null)
{
search_node(tris, bb, node.lo);
}
}
}
return; // Done. We get here after all the recursive calls above.
} // end search_kdtree();
/// Create a node which partitions(cuts) along dimension d, at
/// cut value cv, with child-nodes hi_c and lo_c.
/// If this is a bucket-node containing triangles,
/// they are in the list tris
/// depth indicates the depth of the node in the tree
public KDNode(int d, double cv, KDNode <Triangle> parentNode, KDNode <Triangle> hi_child, KDNode <Triangle> lo_child, LinkedList <Triangle> tlist, int nodeDepth) // depth of node
{
dim = d;
cutval = cv;
parent = parentNode;
hi = hi_child;
lo = lo_child;
tris = new LinkedList <Triangle>();
depth = nodeDepth;
isLeaf = false;
if (tlist != null)
{
isLeaf = true;
foreach (Triangle bo in tlist)
{
tris.AddLast(bo);
}
}
}
/// string repr
//C++ TO C# CONVERTER WARNING: 'const' methods are not available in C#:
//ORIGINAL LINE: string str() const;
//C++ TO C# CONVERTER TODO TASK: The implementation of the following method could not be found:
// string str();
/// build and return a KDNode containing list *tris at depth dep.
protected KDNode <Triangle> build_node(LinkedList <Triangle> tris, int dep, KDNode <Triangle> par)
{ // parent node
//std::cout << "KDNode::build_node list.size()=" << tris->size() << "\n";
if (tris.Count == 0)
{ //this is a fatal error.
Console.Write("ERROR: KDTree::build_node() called with tris->size()==0 !");
Debug.Assert(false);
return(null);
}
Spread spr = calc_spread(tris); // calculate spread in order to know how to cut
double cutvalue = spr.start + spr.val / 2; // cut in the middle
//std::cout << " cutvalue= " << cutvalue << "\n";
if ((tris.Count <= bucketSize) || GlobalMembers.isZero_tol(spr.val))
{ // then return a bucket/leaf node
//std::cout << "KDNode::build_node BUCKET list.size()=" << tris->size() << "\n";
KDNode <Triangle> bucket; // dim cutv parent hi lo triangles depth
bucket = new KDNode <Triangle>(spr.d, cutvalue, par, null, null, tris, dep);
Debug.Assert(bucket.isLeaf);
spr = null;
return(bucket); // this is the leaf/end of the recursion-tree
}
// build lists of triangles for hi and lo child nodes
LinkedList <Triangle> lolist = new LinkedList <Triangle>();
LinkedList <Triangle> hilist = new LinkedList <Triangle>();
foreach (Triangle t in tris)
{ // loop through each triangle and put it in either lolist or hilist
if (t.bb[spr.d] > cutvalue)
{
hilist.AddLast(t);
}
else
{
lolist.AddLast(t);
}
}
/*
* if (hilist->empty() || lolist->empty()) {// an error ??
* std::cout << "kdtree: hilist.size()==0! or lolist.size()==0! \n";
* std::cout << "kdtree: tris->size()= " << tris->size()<< "\n";
* std::cout << "kdtree: hilist.size()= " << hilist->size()<< "\n";
* std::cout << "kdtree: lolist.size()= " << lolist->size()<< "\n";
* BOOST_FOREACH(Triangle t, *tris) {
* std::cout << t << "\n";
* std::cout << t.bb << "\n";
* }
* std::cout << "kdtree: spr->d= " << spr->d << "\n";
* std::cout << "kdtree: cutvalue= " << cutvalue << "\n";
* assert(0);
* }*/
// create the current node dim value parent hi lo trilist depth
KDNode <Triangle> node = new KDNode <Triangle>(spr.d, cutvalue, par, null, null, null, dep);
// create the child-nodes through recursion
// list depth parent
if (hilist.Count > 0)
{
node.hi = build_node(hilist, dep + 1, node);
}
//else
//std::cout << "hilist empty!\n";
if (lolist.Count > 0)
{
node.lo = build_node(lolist, dep + 1, node);
}
else
{
//std::cout << "lolist empty!\n";
}
lolist.Clear();
hilist.Clear();
spr = null;
lolist = null;
hilist = null;
return(node); // return a new node
}