A few simple raytracers that I have written.
List of them
raytracer.cpp- I think this one works fully.
tracer2.cpp- This one has depth of field and a neat scene. Takes a few hours to render at max settings.
minimal.cpp- Not sure if this works.
refraction.cpp- Outputs a render, but not sure if it's correct glass refraction.
/raymarcher- This one is pretty neat. Has rough reflections and OK-organized code. Check out the readme in there.
/simple- Looks the same as raytracer.cpp to me. Not sure what this is for.
All of the renderers output images in the NetPPM format. OpenSeeIt works well for Windows to view these.
You can find renders from some of the programs in the