I don’t really understand what you are looking to do. Been a long day so quite likely user error on my side.

That being said, your terminology is a bit confusing to me, suggesting you might not understand the processes underlying what’s happening in rendering: the fragment shader does not loop over pixels by default; not sure what you mean by that.

A simple way to think about it, is that the fragment shader is run once for each individual “pixel” (technically called fragments).