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

        public Perspective premultiply(Affine b)
        {
            Perspective a = new Perspective(this);
            sx = a.sx * b.sx + a.shx * b.shy;
            shx = a.sx * b.shx + a.shx * b.sy;
            tx = a.sx * b.tx + a.shx * b.ty + a.tx;
            shy = a.shy * b.sx + a.sy * b.shy;
            sy = a.shy * b.shx + a.sy * b.sy;
            ty = a.shy * b.tx + a.sy * b.ty + a.ty;
            w0 = a.w0 * b.sx + a.w1 * b.shy;
            w1 = a.w0 * b.shx + a.w1 * b.sy;
            w2 = a.w0 * b.tx + a.w1 * b.ty + a.w2;
            return this;
        }