the following is the demo of pure CPU implementation of the
famous "raymarching" algorithm. of course, doing that in GLSL
shader will be many times faster (10x? 20x? dunno), but i'm too
lazy to port the necessary gl headers (and don't want to use
derelict for some random reason ;-), so i did it on CPU.
it's basically the fragment shader code, executing on CPU instead
of course, one can use more threads to render image parts, but
i'm too lazy to implement that (let's say that i left this as an
excercise for a reader; i know you all love such "excercises").
you will need Adam's simpledisplay.d and color.d from here.
no OpenGL required.