For the longest time, I've wanted to re-implement the original DOOM engine in Python, and compile it with Shedskin to get reasonable performance. So when I finally ran across a pretty small engine written in Java, by Leonardo Ono, I decided to convert his version to Python.
I left out some optimizations (most notably "visplanes"), for readability and in order to keep everything under 1000 lines of code (while following PEP8). So it could run quite a bit faster still. This is including a WAD loader and interactive Pygame wrapper, that makes it almost feel like you are playing DOOM.
It's interesting how using Python (using just CPython) seems to be about as fast as using assembler back in the day.
This video shows the day-and-night difference in FPS after compilation using Shedskin.
The source code can be found in the Shedskin examples directory.
I may revisit the code now and then, to try and improve readability by adding comments and/or refactoring parts. Patches in this direction very much welcome of course.
In general, we are also always looking to receive more feedback and contributions from the community! While not the 'final' solution to Python performance, Shed Skin is great fun to hack on. See some potential issues for the next release to start looking into.
