/// <summary>
/// Clears the QuadTree of all objects, including any objects living in its children.
/// </summary>
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;
}
/// <summary>
/// Get the child Quad that would contain an object.
/// </summary>
/// <param name="item">The object to get a child for.</param>
/// <returns></returns>
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);
}
/// <summary>
/// Creates a QuadTree for the specified area.
/// </summary>
/// <param name="x">The top-left position of the area rectangle.</param>
/// <param name="y">The top-right position of the area rectangle.</param>
/// <param name="width">The width of the area rectangle.</param>
/// <param name="height">The height of the area rectangle.</param>
public QuadTree(int x, int y, int width, int height)
{
quadTreeRoot = new QuadTreeNode <T>(new Rectangle(x, y, width, height));
}
private QuadTreeNode(QuadTreeNode <T> parent, Rectangle rect)
: this(rect)
{
this.parent = parent;
}
/// <summary>
/// Creates a QuadTree for the specified area.
/// </summary>
/// <param name="rect">The area this QuadTree object will encompass.</param>
public QuadTree(Rectangle rect)
{
quadTreeRoot = new QuadTreeNode <T>(rect);
}