Even color is a non-local effect. Turning two colored pixels on side-by-side on an Apple II makes them white. I can give you an unbounded amount of detail why :

Even color is a non-local effect. Turning two colored pixels on side-by-side on an Apple II makes them white. I can give you an unbounded amount of detail why :-) https://zellyn.github.io/apple2shader/ https://zellyn.github.io/apple2shader/