02-15-2015, 05:24 AM
Do you mean upscaling in-game programmatically? If so, I don't know if it's possible to do so, most engines blur it.
However, if you want to upscale the graphics before putting them in the game, you can do so without blurring it. With GIMP, you can upscale by 200% (or any multiple of 100%) with interpolation set to "None" (Photoshop and other programs probably have similar settings), and it won't blur it. If you upscale it to a weird number though, like 137%, it still won't necessarily blur it, but the sprites will look weird and not very pleasant.
However, if you want to upscale the graphics before putting them in the game, you can do so without blurring it. With GIMP, you can upscale by 200% (or any multiple of 100%) with interpolation set to "None" (Photoshop and other programs probably have similar settings), and it won't blur it. If you upscale it to a weird number though, like 137%, it still won't necessarily blur it, but the sprites will look weird and not very pleasant.