message: use mipmaps when doing importance sampling
diff: @@ -295,7 +295,8 @@ vec3 isEvaluateIBL(const PixelParams pixel, vec3 n, vec3 v, float NoV) {
  vec3 Fr = F * (D * V * ipdf * NoL);
  - vec3 env = decodeDataForIBL(textureLod(light_iblSpecular, l, mipLevel));
  + // we use texture() instead of textureLod() to take advantage of mipmapping
  + vec3 env = decodeDataForIBL(texture(light_iblSpecular, l, mipLevel));
  indirectSpecular += (Fr * env) * invNumSamples;
  }
  }
  