private bool OverlapNode()
{
// Calculate bulk hull for _object
_objectHullX = (_object.X < _object.Last.X) ? _object.X : _object.Last.X;
_objectHullY = (_object.Y < _object.Last.Y) ? _object.Y : _object.Last.Y;
_objectHullWidth = _object.X - _object.Last.X;
_objectHullWidth = _object.Width + ((_objectHullWidth > 0) ? _objectHullWidth : -_objectHullWidth);
_objectHullHeight = _object.Y - _object.Last.Y;
_objectHullHeight = _object.Height + ((_objectHullHeight > 0) ? _objectHullHeight : -_objectHullHeight);
// Walk the list and check for overlaps
bool overlapProcessed = false;
FlxObject checkObject;
while (_iterator != null)
{
checkObject = _iterator.FlxObject;
if (_object == checkObject || !checkObject.Exists || checkObject.AllowCollisions <= 0)
{
_iterator = _iterator.Next;
continue;
}
// Calculate bulk hull for checkObject
_checkObjectHullX = (checkObject.X < checkObject.Last.X) ? checkObject.X : checkObject.Last.X;
_checkObjectHullY = (checkObject.Y < checkObject.Last.Y) ? checkObject.Y : checkObject.Last.Y;
_checkObjectHullWidth = checkObject.X - checkObject.Last.X;
_checkObjectHullWidth = checkObject.Width + ((_checkObjectHullWidth > 0) ? _checkObjectHullWidth : -_checkObjectHullWidth);
_checkObjectHullHeight = checkObject.Y - checkObject.Last.Y;
_checkObjectHullHeight = checkObject.Height + ((_checkObjectHullHeight > 0) ? _checkObjectHullHeight : -_checkObjectHullHeight);
// Check for intersection of the two hulls
if ((_objectHullX + _objectHullWidth > _checkObjectHullX) &&
(_objectHullX < _checkObjectHullX + _checkObjectHullWidth) &&
(_objectHullY + _objectHullHeight > _checkObjectHullY) &&
(_objectHullY < _checkObjectHullY + _checkObjectHullHeight))
{
// Execute callback functions if they exist
if (_processingCallback == null || _processingCallback(_object, checkObject))
{
overlapProcessed = true;
_notifyCallback?.Invoke(_object, checkObject);
}
}
if (_iterator != null)
{
_iterator = _iterator.Next;
}
}
return(overlapProcessed);
}
public bool Execute()
{
bool overlapProcessed = false;
if (_headA.FlxObject != null)
{
var iterator = _headA;
while (iterator != null)
{
_object = iterator.FlxObject;
if (_useBothLists)
{
_iterator = _headB;
}
else
{
_iterator = iterator.Next;
}
if (_object != null && _object.Exists && _object.AllowCollisions > 0 && _iterator != null && _iterator.FlxObject != null && OverlapNode())
{
overlapProcessed = true;
}
iterator = iterator.Next;
}
}
// Advance through the tree by calling overlap on each child
if ((_northWestTree != null) && _northWestTree.Execute())
{
overlapProcessed = true;
}
if ((_northEastTree != null) && _northEastTree.Execute())
{
overlapProcessed = true;
}
if ((_southEastTree != null) && _southEastTree.Execute())
{
overlapProcessed = true;
}
if ((_southWestTree != null) && _southWestTree.Execute())
{
overlapProcessed = true;
}
return(overlapProcessed);
}
private void AddToList()
{
FlxLinkedList ot;
if (_list == A_LIST)
{
if (_tailA.FlxObject != null)
{
ot = _tailA;
_tailA = FlxLinkedList.Recycle();
ot.Next = _tailA;
}
_tailA.FlxObject = _object;
}
else
{
if (_tailB.FlxObject != null)
{
ot = _tailB;
_tailB = FlxLinkedList.Recycle();
ot.Next = _tailB;
}
_tailB.FlxObject = _object;
}
if (!_canSubdivide)
{
return;
}
if (_northWestTree != null)
{
_northWestTree.AddToList();
}
if (_northEastTree != null)
{
_northEastTree.AddToList();
}
if (_southEastTree != null)
{
_southEastTree.AddToList();
}
if (_southWestTree != null)
{
_southWestTree.AddToList();
}
}
public void Dispose()
{
_headA = null;
_headB = null;
_tailA = null;
_tailB = null;
_northWestTree = null;
_northEastTree = null;
_southEastTree = null;
_southWestTree = null;
_object = null;
_processingCallback = null;
_notifyCallback = null;
Exists = false;
next = _cachedTreesHead;
_cachedTreesHead = this;
_NUM_CACHED_QUAD_TREES++;
}
public void Reset(float x, float y, float width, float height, FlxQuadTree parent = null)
{
Exists = true;
Set(x, y, width, height);
_headA = _tailA = FlxLinkedList.Recycle();
_headB = _tailB = FlxLinkedList.Recycle();
if (parent != null)
{
FlxLinkedList iterator;
FlxLinkedList ot;
if (parent._headA.FlxObject != null)
{
iterator = parent._headA;
while (iterator != null)
{
if (_tailA.FlxObject != null)
{
ot = _tailA;
_tailA = FlxLinkedList.Recycle();
ot.Next = _tailA;
}
_tailA.FlxObject = iterator.FlxObject;
iterator = iterator.Next;
}
}
if (parent._headB.FlxObject != null)
{
iterator = parent._headB;
while (iterator != null)
{
if (_tailB.FlxObject != null)
{
ot = _tailB;
_tailB = FlxLinkedList.Recycle();
ot.Next = _tailB;
}
_tailB.FlxObject = iterator.FlxObject;
iterator = iterator.Next;
}
}
}
else
{
_min = (int)Math.Floor((Width + Height) / (2 * Divisions));
}
_canSubdivide = Width > _min || Height > _min;
_northWestTree = null;
_northEastTree = null;
_southWestTree = null;
_southEastTree = null;
_leftEdge = X;
_rightEdge = Right;
_halfWidth = Width / 2;
_midpointX = _leftEdge + _halfWidth;
_topEdge = Y;
_bottomEdge = Bottom;
_halfHeight = Height / 2;
_midpointY = _topEdge + _halfHeight;
}