I just finished a long running goal of mine of duplicating the Photoshop “color dodge” effect in OpenGL with a very simple register combiner.
I spent an hour or so today trying to figure out what it does at work, then I got home and couldn’t get it just right, and then and ONLY then I realized it was as simple as:
result=(background color)+(overlay color)
And I had a nice long equation too and a very elegant two stage combiner, but that produced too dim results. Oh well, it looks nice and will serve my purposes. Thanks, nVidia!