x, y, z, t, u, v, w, a, b, c, 
a*b-c*w
u*y+v*x-x*y
-b*t-c*x+t*x
-a*z-w*y+y*z
b*v-c*u+c*z-v*z
-a*u+t*u-t*w+v*w
