-static const Vec3 grid_color = Vec3(1.0, 0.07, 1.0);
-static const Vec3 mid_color = Vec3(0.133, 0.006, 0.612);
-static const Vec3 horiz_color = Vec3(0.612, 0.006, 1.0);
-static const Vec3 zenith_color = Vec3(0.029, 0.029, 0.029);
-static const Vec3 fog_color = Vec3(0.01, 0.01, 0.01);