source 2008 Bernstein--Lange--Rezaeian Farashahi
assume Z2 = 1
compute W1 = X1 + Y1
compute w2 = X2 + Y2
compute A = X2^2 + X2
compute B = Y2^2 + Y2
compute D = W1 Z1
compute E = d1 Z1^2
compute H = (E + d2 D) w2
compute I = d1 Z1
compute U = E + A D
compute V = E + B D
compute Z3 = U V
compute X3 = Z3 Y2 + (H + X1(I + A(Y1 + Z1))) V
compute Y3 = Z3 X2 + (H + Y1(I + B(X1 + Z1))) U