@Override
public Optional<TRSRTransformation> apply(Optional<? extends IModelPart> part)
      {
          if(part.isPresent())
          {
              // This whole thing is subject to change, but should do for now.
              UnmodifiableIterator<String> parts = Models.getParts(part.get());
              if(parts.hasNext())
              {
                  String name = parts.next();
                  // only interested in the root level
                  if(!parts.hasNext() && hidden.contains(name))
                  {
                      return value;
                  }
              }
          }
          return Optional.absent();
      }
 

@Override
public IBakedModel load(final Map<String, Float> key) throws Exception {
	final IModelState clipTransform = part -> {
		if (!part.isPresent()) return Optional.empty();

		final IModelPart maybeJoint = part.get();
		if (!(maybeJoint instanceof IJoint)) return Optional.empty();

		final IJoint joint = (IJoint)part.get();
		return Optional.of(evaluator.evaluate(joint, key));
	};
	return bakeModelWithTransform(clipTransform);
}
 

@Override
public Optional<TRSRTransformation> apply(
		Optional<? extends IModelPart> part) {
	return Optional.empty();
}