Hmm that’s interesting. In the 3.3.0 source, it isn’t final, but in the current version it is. I wonder then if there’s a reason not to have a setter. I’ve found this thread which indicates the setFrameBufferFormat function was contributed through a PR, so there’s a precedent: Ability to change image format for FilterPostProcessor
I’ve never made a PR before, so I’ll have to read up on that. If it gets rejected, maybe at least the reason will shed some light on this topic.
EDIT: I have seen pspeed’s filter in Mythruna, and I think the stencil-based volumetric shadows fit the look I’m going for a bit better. I particularly like how they “flow” all the way down walls instead of wrapping over the edge.