void drawTree <T>(QuadTree <T> qt) where T : IRegion
{
Vector2 p1 = new Vector2(qt.Span.XMax, qt.Span.YMin);
Vector2 p2 = new Vector2(qt.Span.XMin, qt.Span.YMin);
Vector2 p3 = new Vector2(qt.Span.XMin, qt.Span.YMax);
Vector2 p4 = new Vector2(qt.Span.XMax, qt.Span.YMax);
float t = 3f;
GraphicsUtils.DrawLineTop(p1, p2, Color.GreenYellow, t);
GraphicsUtils.DrawLineTop(p2, p3, Color.GreenYellow, t);
GraphicsUtils.DrawLineTop(p3, p4, Color.GreenYellow, t);
GraphicsUtils.DrawLineTop(p4, p1, Color.GreenYellow, t);
if (qt.SubTrees != null)
{
foreach (var qtsub in qt.SubTrees)
{
drawTree <T>(qtsub);
}
}
}