public static Vector2 CGSizeApplyAffineTransform(Vector2 size,CGAffineTransform xform){
Vector2 s;
s.x=xform.a*size.x+xform.c*size.y;
s.y=xform.b*size.x+xform.d*size.y;
return s;
}
public static Rect CGRectApplyAffineTransform(Rect rect, CGAffineTransform transform)