miscela is an openFrameworks app i use to layer GLSL fragment shaders and np-pixelscript lua scripts. Still highly experimental.
usage is something like this:
miscela path/to/optional/config.json path/to/shader.frag path/to/pixelscript.lua other/shader.frag some/image/overlay.png
Fragment shader use the last script/fragment output as uniform u_tex0, png/jpg/gif/bmp images and mov/mp4 video can be passed and they are overlayed. .json files can be passed to set some configs.
You need ofxDotFrag and np-pixelscript
miscela Nicola Pisanti MIT License 2019