message: gltfio: do not set clear coat in GLTFIO_LITE config.
  This avoids an assertion in debug builds. We will document this behavior
  much more thoroughly in a subsequent PR.
  Fixes
diff: @@ -191,9 +191,12 @@ MaterialInstance* UbershaderLoader::createMaterialInstance(MaterialKey* config,
  mi->setDoubleSided(config->doubleSided);
  mi->setCullingMode(config->doubleSided ? CullingMode::NONE : CullingMode::BACK);
  + #if !GLTFIO_LITE
  +
  + // Initially, assume that the clear coat texture can be honored. This is changed to false when
  + // running into a sampler count limitation. TODO: check if these constraints can now be relaxed.
  bool clearCoatNeedsTexture = true;
  - #if !GLTFIO_LITE
  mat3f identity;
  mi->setParameter("baseColorUvMatrix", identity);
  mi->setParameter("metallicRoughnessUvMatrix", identity);
  @@ -229,6 +232,14 @@ MaterialInstance* UbershaderLoader::createMaterialInstance(MaterialKey* config,
  getUvIndex(config->transmissionUV, config->hasTransmissionTexture));
  }
  }
  + #else
  +
  + // In the GLTFIO_LITE configuration we do not support UV matrices, clear coat, sheen, specular
  + // glossiness, or transmission. For more details, see `gltflite.mat.in`. To configure a custom
  + // set of features, create your own MaterialProvider class, perhaps using UbershaderLoader as a
  + // starting point.
  + const bool clearCoatNeedsTexture = false;
  +
  #endif
  TextureSampler sampler;
  