OpenGL uses power-of-two textures. This is because some GPUs only accept power-of-two textures due to MipMapping. Using these power-of-two textures causes problems when drawing a texture larger than it is.
I had thought of one way to workaround this, which is to only use the PO2 ratios when we're making the texture smaller than it actually is, and using a 1:1 ratio when we're making it bigger, but will this create compatibility issues with some GPUs?
If anybody knows whether issues would occur (I cannot check this as my GPU accepts NPO2 Textures), or a better workaround, I would be grateful.