Sphere tracing, rendered in ASCII (well, VT100/ANSI terminal emulation really)
This is basically the ASCII equivalent of a basic Shadertoy raymarching demo.
cmake .
make
There are a couple demos in here, one which has a bunch of random objects on top of a checkerboard with the light positioned at the camera, and another one which renders the Square logo (since it was easy to represent with constructive solid geometry, and some of my friends work at Square).
It's pretty slow and unoptimized. I plan on using this technique on a more elaborate obfuscated C demo someday but until then, this is a sandbox for experiments.
There is also my own webgl/glsl sphere tracing sandbox in webgl.html.