Yes I want something to simulate the Game Boy Player, because as far as I know, no emulator can generate it’s border like BSNES generate Super Game Boy border, So what it actually would do is to play a GBA game on a 4:3 aspect without “harming” GBA true aspect ratio which is inside the border. I think I can do it with an overlay, but my ideia was for the border to be whitin the shader for it to get the effects (curvature, scanlines etc.)
Sorry for confusing you man! hahah, If this is to hard, or irrelevant there’s no problem!