here
p -0.5 0.5 0.75
p 0.5 0.5 0.75
p 0.5 0 0
p -0.5 0 0
p -0.75 0 0.75
p 0.75 0 0.75

p -0.5 0.5 2.25
p 0.5 0.5 2.25
p 0.5 0 2.25
p -0.5 0 2.25
mtl klaashele
f 0 1 2 3
f 0 3 4
f 1 2 5

f 0 1 7 6
f 1 5 8 7
f 0 4 9 6
f 6 7 8 9