Right now I'm working on the backgrounds for my shoot'em up game. It's a classic "plane shoots planes" game, but with model kits fighting in homes, museums, hobby shops etc! Right now I'm working on the French levels, I'm touring without buying these flats in France (for free, thanks to th...

If it beats 24 fps on my garbage laptop, it's good to go, it means it'll hav at least 30 fps on a Nokia 3310

Are you sure it's not something working "behind" your program on your computer? Sometimes, you're searching for an issue somewhere and it's in a completely different place.
Edit, I'm stupid, I've just read as I posted that it happens on a Raspberry Pi and not on a PC. Sorry!

Looks like a cool project, I'll definitely be following that. I have a lot of work these days so I can't really play the demo, but I may get some free time by April!

Man, someone should give you a medal already. I'm looking at your images for my game, and I'm fairly sure I'm far from being the only one!