it looks like i will just make a tilesheet/spritesheet generated on the fly, at init time. since i hate spritesheets so i'm not using them in my actual game, just behind the scenes. since texture2darrays apparently have not wholly great hardware support, and if i send a texture2darray composed of 16x16 textures, i heard from a gpu dev that it'll probably get padded out to 128x128 automatically..