message: Fix a little bit..
diff: @@ -116,16 +116,16 @@ inline vector<3, T> xyz_to_rgb(vector<3, T> const& xyz)
  template <typename SPD, typename T = float>
  VSNRAY_FUNC
  -inline vector<3, T> spd_to_rgb(SPD const& spd, T lmin = T(400.0), T lmax = T(700.0), T step = T(1.0))
  +inline vector<3, T> spd_to_rgb(SPD const& spd, float lmin = 400.0f, float lmax = 700.0f, float step = 1.0f)
  {
  T x(0.0);
  T y(0.0);
  T z(0.0);
  T n(0.0);
  - for (T lambda = lmin; lambda <= lmax; lambda += step)
  + for (float lambda = lmin; lambda <= lmax; lambda += step)
  {
  - auto p = spd(lambda);
  + auto p = spd(T(lambda));
  x += p * cie_x(lambda);
  y += p * cie_y(lambda);
  