This wouldn't run in FS-UAE, right?
We're at the cutting edge on soon-to-be-released Open BSD 6.3 with SDL2.0.8. I'm the new maintainer of that port.
The only function that's not working is SDL_GetBasePath. Seems to be used rarely and usually can be worked around.
OpenBSD's API/ABI and the libs are updated regularly, so bundled libs usually don't work (short lifetime until they would need recompiling/relinking).
If Tower 57 is written in c++/SDL2, the best (only?) chance for us OpenBSD folks would be an open-source version of the game engine (assets an still be sold). We have a few examples, like Tales of Maj'Eyal (in ports) or Eldritch (port in development)... I know that's probably not the right thing at the moment - maybe keep it in the back of your head...
It does, when I tried it ran on FS-UAE but was way too slow. *BUT*:
it runs in latest WinUAE 3.6.1 (earlier versions had broken sound here) under AmigaOS4. Right now fullscreen-mode doesn't work (at least not with the std. PicassoIV emu, I will change that soon though), but window-mode works flawlessly.
In fact, when running the game inside that WinUAE in a 480x270 window, then it runs almost as fast as the native official PC Steam version on my same PC (i7 4790K), which should give you a nice hint by how much I accelerated the original code...
It won't run playable in FS-UAE, only WinUAE 3.6.1 so far.
An A4000 3.1 40.68 Kickstart is good. But as being said: forget it with FS-UAE.
But why not use Wine? Dunno if their PC version works, but:
While I developed the Amiga version and completely minced the original code I also created a Win32 "waste product" en passant.
It's practically identical to the Amiga version (e.g. software rendering, OpenAL for sound, all fixes and optimizations I made) and uses the techniques I also used for other games I wrote before - which all work flawlessly via Wine.
Besides that: that Win32 build runs circles around the official PC version performance-wise (~ 850 to more than 1000 fps on my Windows machine, or even better: more than 300 fps on my i5 notebook in situations where the official Steam version drops to 15 fps on that machine... ). Only drawback: like the Amiga versions it's based on version 19.44 of the game.
Who knows, maybe Pixwerk donate me enough to get it :D
Well, maybe use case is unusual in that I'd like to explore if it can run on OpenBSD, and there's no wine on OpenBSD (and based on prior discussions/efforts never will be), but there's fs-uae. I understand it likely won't be playable based on your description. Would try it anyway just to see - maybe one day computers and/or FS-UAE get faster.
We are essentially limited to open-source games, whatever can run in an emulator, and (lately) FNA games. Tower 57 would be an interesting entry if one day it actually runs okay inside FS-UAE.