2D Filters: checking different pixels?

Hello again, friends. Just wondering if there’s a way to sample/check a pixel slightly offset from the subject pixel, so as to obtain proximity information on the subject pixel… Like to check if the subject pixel is within 5 pixels of a bright area (offset pixel sampled).
Thanks!

There was some kind of HDR 2d filter here , that checks the pixels color and position(by color) on the screen to see if the screen is mostly bright or dark and then applies its self. It might be useful for you, unfortunately , I don’t remember the link, but you can try to find it.

Excellent, thank you. I know MartinsUpitis has one posted somewhere… I’ll look into it again.