anchor.diff:    // Must be in sync with UnpackSpotLightInfo
     @override
     void ExtractInfo(Float32List m, int o) {
  -    m[o + 0] = _pos.x;
  -    m[o + 1] = _pos.y;
  -    m[o + 2] = _pos.z;
  +    m[o + 0] = pos.x;
  +    m[o + 1] = pos.y;
  +    m[o + 2] = pos.z;
       //
       m[o + 4] = dir.x;
       m[o + 5] = dir.y;
  
positive.code: }
  
  class SpotLight extends Light {
    VM.Vector3 _pos;
    VM.Vector3 dir;
    VM.Vector3 _colDiffuse;
    VM.Vector3 _colSpecular;
  
negative.code: }
  
  class PointLight extends Light {
    VM.Vector3 pos;
    VM.Vector3 _colDiffuse;
    VM.Vector3 _colSpecular;
    double _range;
    double _glossiness;
  
    PointLight(String name, this.pos, this._colDiffuse, this._colSpecular,
        this._range, this._glossiness)
        : super(name, lightTypePoint);
  
    // Must be in sync with UnpackPointLightInfo
    @override
    void ExtractInfo(Float32List m, int o) {
      m[o + 0] = pos.x;
      m[o + 1] = pos.y;
      m[o + 2] = pos.z;
      //
      m[o + 8] = _colDiffuse.x;
      m[o + 9] = _colDiffuse.y;
  