QuadTree *AllocTree(LRect rect, QuadTree *tree)
{
var ptr = QuadTreeFactory.AllocQuadTree();
*ptr = new QuadTree(rect, tree);
return(ptr);
}
private void Split()
{
var hx = _bounds.width / 2;
var hz = _bounds.height / 2;
var sz = new LVector2(hx, hz);
//split a
var aLoc = _bounds.position;
var aRect = new LRect(aLoc, sz);
//split b
var bLoc = new LVector2(_bounds.position.x + hx, _bounds.position.y);
var bRect = new LRect(bLoc, sz);
//split c
var cLoc = new LVector2(_bounds.position.x + hx, _bounds.position.y + hz);
var cRect = new LRect(cLoc, sz);
//split d
var dLoc = new LVector2(_bounds.position.x, _bounds.position.y + hz);
var dRect = new LRect(dLoc, sz);
fixed(QuadTree *thisPtr = &this)
{
_childA = AllocTree(aRect, thisPtr);
_childB = AllocTree(bRect, thisPtr);
_childC = AllocTree(cRect, thisPtr);
_childD = AllocTree(dRect, thisPtr);
}
//assign QuadTrees
for (int i = _bodyCount - 1; i >= 0; i--)
{
var child = GetQuadrant(_bodies[i]->pos);
child->AddBody(_bodies[i]);
_bodies[i] = null;
}
}
private void _GetBodies(LRect rect, List <long> bods)
{
//no children
if (_childA == null)
{
for (int i = 0; i < _bodyCount; i++)
{
bods.Add((long)(_bodies[i]));
}
}
else
{
if (_childA->ContainsRect(rect))
{
_childA->_GetBodies(rect, bods);
}
if (_childB->ContainsRect(rect))
{
_childB->_GetBodies(rect, bods);
}
if (_childC->ContainsRect(rect))
{
_childC->_GetBodies(rect, bods);
}
if (_childD->ContainsRect(rect))
{
_childD->_GetBodies(rect, bods);
}
}
}
public QuadTree(LRect bounds, int maxBodiesPerNode = 6, int maxLevel = 6)
{
_bounds = bounds;
_maxBodiesPerNode = maxBodiesPerNode;
_maxLevel = maxLevel;
_childA = null;
_childB = null;
_childC = null;
_childD = null;
_curLevel = 0;
_parent = null;
_bodyCount = 0;
_debugId = curDebugId++;
_bodies = QuadTreeFactory.AllocPtrBlock(_maxBodiesPerNode);
}
public bool ContainsRect(LRect rect)
{
return(_bounds.Overlaps(rect));
}
public List <long> GetBodies(LRect rect)
{
_tempPtrList.Clear();
_GetBodies(rect, _tempPtrList);
return(_tempPtrList);
}
private QuadTree(LRect bounds, QuadTree *parent)
: this(bounds, parent->_maxBodiesPerNode, parent->_maxLevel)
{
_parent = parent;
_curLevel = parent->_curLevel + 1;
}