0 0 0 a
0 1/2 1/2 a
1/2 0 0 b
1/2 1/2 1/2 b
0 0 1/2 c
0 1/2 0 c
1/2 0 1/2 d
1/2 1/2 0 d
x y z e
-x y+1/2 -z+1/2 e
-x -y -z e
x -y+1/2 z+1/2 e