Build Minimal Little Voxel Sandbox

At some point I wanted a voxel building sandbox in the vein of Minecraft Classic (if anyone remembers that anymore). I had some free time, and a laptop that only supported OpenGL 1.* so I threw something together. It's now really really old, it ought to still work but the programming style is probably awful. It's world is also a tiny finite cube.

Features:

lightweight cross-platform voxel sandbox
built on C, SDL, and OpenGL 1.5 (supposedly, I may have messed parts of it up?)
coloured lighting
liquid physics and cellular automata

Screenshot: some glass vats of water and lava with fancy lighting
Screenshot: flying above a tiny island (running under Windows XP)

Usage

Source code is available below. It compiles under Linux, and I did at some point cross compile it for Windows, but I'm afraid anyone not running Linux is on their own.

Build dependencies:

C compiler (tested with GCC)
SDL2
SDL2 image
SDL2 mixer
OpenGL 1.5

Further instructions are given in README.md

Source code

License

I'm not actually sure, looks like a variant of MIT or BSD.