public void Rotate(double sx, double sy, List <IPointShape> points, ref double rotateAngle)
{
var centerX = Bounds.CenterX;
var centerY = Bounds.CenterY;
var p0 = new Point2(centerX, centerY);
var p1 = new Point2(sx, sy);
var angle = p0.AngleBetween(p1) - 270.0;
var delta = angle - rotateAngle;
var radians = delta * (Math.PI / 180.0);
var matrix = Matrix2.Rotation(radians, centerX, centerY);
TransformPoints(ref matrix, points);
rotateAngle = angle;
Update();
}
