BETTER METHOD: https://scratch.mit.edu/projects/101029636/ @ilikelegos made an awesome tile-based scrolling engine, but if you played in fullscreen there were gaps between the tiles. I 'fixed' them. If you set the size of the tiles to 204% and the background to 102%, there are no white lines but the art isn't distorted. To keep the smaller tiles on screen, they costumes need to be redrawn 8 times bigger, with a half-pixel in 2 opposite corners. Ok, it is a little distorted, but you don't notice it that much if you aren't looking for it, and it's a heck of a lot less noticeable then a huge white grid.