internal static RectangleF Intersect( RectangleF lhs, RectangleF rhs )
{
RectangleF r;
r._left = lhs._left > rhs._left ? lhs._left : rhs._left;
r._top = lhs._top > rhs._top ? lhs._top : rhs._top;
r._right = lhs._right < rhs._right ? lhs._right : rhs._right;
r._bottom = lhs._bottom < rhs._bottom ? lhs._bottom : rhs._bottom;
return r;
}
}