private void Subdivide()
{
Point size = new Point(rect.Width / 2, rect.Height / 2);
Point mid = new Point(rect.X + size.X, rect.Y + size.Y);
childTL = new QuadTreeNode <T>(this, new Rectangle(rect.Left, rect.Top, size.X, size.Y));
childTR = new QuadTreeNode <T>(this, new Rectangle(mid.X, rect.Top, size.X, size.Y));
childBL = new QuadTreeNode <T>(this, new Rectangle(rect.Left, mid.Y, size.X, size.Y));
childBR = new QuadTreeNode <T>(this, new Rectangle(mid.X, mid.Y, size.X, size.Y));
for (int i = 0; i < objects.Count; i++)
{
QuadTreeNode <T> destTree = GetDestinationTree(objects[i]);
if (destTree != this)
{
destTree.Insert(objects[i]);
Remove(objects[i]);
i--;
}
}
}
internal void Clear()
{
// Clear out the children, if we have any
if (childTL != null)
{
childTL.Clear();
childTR.Clear();
childBL.Clear();
childBR.Clear();
}
// Clear any objects at this level
if (objects != null)
{
objects.Clear();
objects = null;
}
// Set the children to null
childTL = null;
childTR = null;
childBL = null;
childBR = null;
}
private QuadTreeNode <T> GetDestinationTree(QuadTreeObject <T> item)
{
// If a child can't contain an object, it will live in this Quad
QuadTreeNode <T> destTree = this;
if (childTL.QuadRect.Contains(item.Data.Rect))
{
destTree = childTL;
}
else if (childTR.QuadRect.Contains(item.Data.Rect))
{
destTree = childTR;
}
else if (childBL.QuadRect.Contains(item.Data.Rect))
{
destTree = childBL;
}
else if (childBR.QuadRect.Contains(item.Data.Rect))
{
destTree = childBR;
}
return(destTree);
}
public QuadTree(int x, int y, int width, int height)
{
quadTreeRoot = new QuadTreeNode <T>(new Rectangle(x, y, width, height));
}
public QuadTree(Rectangle rect)
{
quadTreeRoot = new QuadTreeNode <T>(rect);
}
private QuadTreeNode(QuadTreeNode <T> parent, Rectangle rect)
: this(rect)
{
this.parent = parent;
}