Inigo Quilez   ::     ::  
Thanks to the demoscene outreach group guys me and few other demosceners could give some seminars at nvscene in San Jose (California) back in 2008. It was some very interesting days, where we enjoyed a nice party, learned a lot with cool seminars and met the American demoscene. The hotel was in the very same conference center, so it was really cool :) Ah yes, my presentation was about rendering procedural images based on raymarching in the GPU, in the context of four kilobytes demos.

The presentation does first introduce the four kilobytes demos produced by the demosceners. This was a good chance to show the world what amazing things demosceners are doing today, so I showed all sort of 1k and 4k intros featuring raytracing, raymarching and similar techniques. Then I quickly introduced the concept of raymarching into voxels, analytic surfaces, and procedural surfaces without any close analytical expression. Then I introduced the concept of distance fields as a rendering acceleration technique and procedural modeling tool. This was quite a forgotten field of CG, and I like to think I somehow rebumped it by showing the making of Slisesix (the image on the right) what is computed by rendering on distance fields, and fits in 3 kilobytes (that includes the models, textures, lighting, materials, and renderer).

I quickly introduced some of the most basic operations in procedural distance fields as cloning, deforming and blending. I also explained how to efficiently compute ambient occlusion and soft shadows.

I think it's a rather complete and fun read.

The presentation was a real time with interactive slides, but since 2008 tech has changed a lot and it's no longer compatible with modern systems. So instead I'm linking to a static PDF version of it for you to download: Rendering Worlds With Two Triangles.