public void Expand(IntPoint2D point)
{
if (point.X < _min.X)
_min.X = point.X;
if (point.Y < _min.Y)
_min.Y = point.Y;
if (point.X > _max.X)
_max.X = point.X;
if (point.Y > _max.Y)
_max.Y = point.Y;
}