I believe a combo would be the best bet for this.
Essentially I want to do 2 things. First, I want to be able to accomplish the same thing this shader accomplishes:
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Basically specify 4 colors and the shader applies that palette to ALL objects automatically.
The second thing I need would most likely require an extension?
I want to be able to loop through all pixels of an object or the screen and compare where they overlap.
I want to then be able to apply a color to any overlapping pixels. Example below:
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Compensation is negotiable.