RenderObjects is very powerful and allows for some cool new artist friendly work flows. But we are still tied to using the old layer system to filter out what we need to render which restricts its functionality. For example, with the 'outline' example here: You could put all enemy entity renderers into one renderer layer mask, and all friendly entities into another. Then you could have a Red outline and a Blue outline effect, and only the entities could be colored appropriately for their team. It allows us to create some interesting rendering effects like the Outlines example, and allows us to expose the effects to our artists in a way where they can pick which objects opt in to the effect simply by assigning it to the appropriate renderer layer mask. And since objects can be part of multiple renderer layer mask, they can even opt in to multiple effects, etc.