Inigo Quilez   ::     ::  
How many raytracers have you written? I think I must have done 50 or so by now, some really simple and specific for a demo, others more generic and one even professional. This is just one more of those raytracers, done during 2003 after I read read about Renderman (by Pixar) and I encountered the word "shader" for the first time in my life. Well, then since everything has been about shaders around me.

This page contains some images and a video of the first raytracer I wrote that supported light and surface shaders as standlone little programs to run during surface and light evaluation. I did everything in software rendering of course, and I implemented all of the basic shaders I could find in that paper. This paper by Pixar was such a true revelation to me, and the reason for me to buy a graphics card that same week and start learning OpenGL and hardware shaders the month after (which result was Paradise). The two weeks test raytracer contained the following features:

Raytracing experiments of 2001 and 2003

Reflecions - 2001

Polyon meshes - 2001

Procedural shader, motion blur - 2003

Ambient occlusion - 2003

Volumetric raymarching - 2003

Light scattering - 2003

Julia sets (raymarching) - 2001

Julia sets (raymarching) - 2001