anchor.diff:    WebGLMaterial._internal(Material material) : _material = material;
     
     factory WebGLMaterial(Material material) {
  +
       if (material["__webglMaterial"] == null) {
         var webglMaterial = new WebGLMaterial._internal(material);
         material["__webglMaterial"] = webglMaterial;
  
positive.code:   bool get needsSmoothNormals()
      => (_material != null) && (shading != null) && (shading == Three.SmoothShading);
  
  // only MeshBasicMaterial and MeshDepthMaterial don't need normals
    bool get needsNormals() 
      => ! (( _material is MeshBasicMaterial && (envMap == null) ) || _material is MeshDepthMaterial);
        
  
negative.code: 
  	}
  
  	bool bufferGuessUVType ( material ) {
  
  		// material must use some texture to require uvs
  
  