Most of the more complex shaders on shadertoy are raymarching signed distance fields. There are a good amount of resources covering this technique. A couple o

Most of the more complex shaders on shadertoy are raymarching signed distance fields. There are a good amount of resources covering this technique. A couple of recommendations: http://9bitscience.blogspot.com/2013/07/raymarching-distance-fields_14.html http://9bitscience.blogspot.com/2013/07/raymarching-distance... http://www.iquilezles.org/www/articles/raymarchingdf/raymarchingdf.htm http://www.iquilezles.org/www/articles/raymarchingdf/raymarc... (from Inigo Quilez, founder of shadertoy) http://www.pouet.net/topic.php?which=8177&page=1 http://www.pouet.net/topic.php?which=8177&page=1 I gave a talk at NYU a few years ago about raymarching signed distance fields which is available here (https://www.youtube.com/watch?v=DXFEOI2SsNY https://www.youtube.com/watch?v=DXFEOI2SsNY) One of the best ways to start understanding shader toy shaders is to modify or remove code and run it. This way you can visualize what functions in the shader contribute to the image, and in what ways. In some of the more complex shaders there can be almost random looking strings of math to generate a procedural texture or a specific post process effect, and breaking these down can help you gain an intuitive understanding of how to "paint with math".