programming GEGL operations through node properties
Submitted by Joao S. O. Bueno
Link to original bug (#161449)
Description
I had initially thought of this for the GIMP - a way to have a custom compositing mode that would have,as one of it's parameters, a bytecode stack allowing almost programaticaly operations between two pixel values.
I had built a patch for it, back in GIMP 1.3.15 - the code won't apply to anything existing today. Either, I did not find at the time a way to pass down the opcode string to function, so it is sort of hardcoded in the compositing code.
Anyway, the part that parses the bytecode and composites 8 bit RGBA pixels using intermediary 16.16 fixed point values for the channels used to work.
I will attach the patch here, so that people can have an idea of how it worked, and make use of any concept in there that could be used in GEGL.