Hi - (and if I may interfere…)
I end up using the Technologicat system ( CommonFilters - some new filters, and the future - Panda Features in Development - Panda3D), as it enables you to easily use multi stacked filters. I use it, with some adaptations (e.g. simplification, convertion from cg to GLSL, and python upgrade).
One thing that is still a little bit annoying is that FilterManager depends on the camera. This implies to regenerate all the Filters at each camera change. I don’t know whether or not this can be addressed by another design in a next future…
Having an easy-to-use, customizable and multi-stacked post processing “framework” is one thing that could be interesting for P3D 11.