message: Make sure sun in the skybox blooms enough
  This is a temporary (hopefully) hack to make the skybox sun look
  better when bloom is enabled (this doesn't affect how the "sun" lights
  objects, only how it looks in the skybox).
  This scale factor was adjusted empirically.
diff: @@ -28,6 +28,7 @@ fragment {
  if (materialParams.showSun && frameUniforms.sun.w >= 0.0f) {
  vec3 direction = normalize(variable_eyeDirection.xyz);
  vec3 sun = frameUniforms.lightColorIntensity.rgb * frameUniforms.lightColorIntensity.a;
  + sun *= 4.0 * PI; // emprirical factor to make the sun look better with bloom
  float cosAngle = dot(direction, frameUniforms.lightDirection);
  float x = (cosAngle - frameUniforms.sun.x) * frameUniforms.sun.z;
  float gradient = pow(1.0 - saturate(x), frameUniforms.sun.w);
  