glsl techniques

Short explanations of the ideas behind the shaders here. Every page has a minimal example running next to the text — edit it, break it, fork it — and links to every shader in the corpus that uses the technique. All CC0, so take any of it.

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  Raymarching

  How a fragment shader draws 3D without any geometry: march a ray forward in steps that are guaranteed safe, using a function that measures distance to the nearest surface.

  87 shaders →
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  Thin-film interference

  Why soap bubbles and oil slicks have colour when neither the soap nor the oil is coloured — and how to get the same effect from three cosines and a viewing angle.

  28 shaders →
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  Feedback

  Give a shader a memory of its own last frame and it stops drawing pictures and starts growing them — trails, smoke, reaction-diffusion, and most things that look alive.

  29 shaders →

After the API or the agent docs instead? Those live in /docs. Want to add to the corpus? post a shader.