gistfile1.nim

proc rotate(axis: TVector, angle: float): TMat4 =
  let cosine    = cos(angle).float32
  let sine    = sin(angle).float32
  let oneminuscos = 1 - cosine
  let xsquared    = axis[0].pow(2.0)
  let ysquared    = axis[1].pow(2.0)
  let zsquared    = axis[2].pow(2.0)
  result = [[cosine + oneminuscos*xsquared, oneminuscos*axis[0]*axis[1] - axis[2]*sine, oneminuscos*axis[0]*axis[2] + axis[1]*sine, 0],
            [oneminuscos*axis[0]*axis[1] + axis[2]*sine, cosine + oneminuscos*ysquared, oneminuscos*axis[1]*axis[2] - axis[0]*sine, 0],
            [oneminuscos*axis[0]*axis[2] - axis[1]*sine, oneminuscos*axis[1]*axis[2] + axis[0]*sine, cosine + oneminuscos*zsquared, 0],
            [0f32,                                                0f32,                                        0f32,             1f32]]