NewTOAPIA.Graphics.Perspective.Transform C# (CSharp) Method

        public void Transform(ref double px, ref double py)
        {
            double x = px;
            double y = py;
            double m = 1.0 / (x * w0 + y * w1 + w2);
            px = m * (x * sx + y * shx + tx);
            py = m * (x * shy + y * sy + ty);
        }

 public void scaling(out double x, out double y)
 {
     double x1 = 0.0;
     double y1 = 0.0;
     double x2 = 1.0;
     double y2 = 1.0;
     Perspective t = new Perspective(this);
     t *= Affine.NewRotation(-rotation());
     t.Transform(ref x1, ref y1);
     t.Transform(ref x2, ref y2);
     x = x2 - x1;
     y = y2 - y1;
 }