(defn
look-at-matrix
[target up]
(let
[z-axis
(normalize target)
x-axis
(normalize (cross up z-axis))
y-axis
(normalize (cross z-axis x-axis))]
[(nth x-axis 0)
(nth x-axis 1)
(nth x-axis 2)
(nth y-axis 0)
(nth y-axis 1)
(nth y-axis 2)
(nth z-axis 0)
(nth z-axis 1)
(nth z-axis 2)]))