Aside from being ugly and probably not great to maintain (and of course why is this happening if texture arrays exist), I bet it's a lot faster than y'all are thinking.

If your 34 textures are varying sizes and formats then I would reconsider your approach to rendering whatever it is you're rendering.

They are varying sizes so texture arrays will probably not work. Its mostly planet textures, and some of those are huge. They dont fit into memory all at once so I have to load/unload them on demand, preferably without the game freezing for multiple seconds while doing so, or worse, crashing. That shader actually runs quite well if not for that artifact..