To watch first

In fact it’s simple, all the links to start about shaders are at the bottom of the Shadertoy main page !
Fabrice Neyret’s blog is very usefull for beginners. Like IQ pages, a lot of usefull functions by MERCURY group, a gold mine. A lot of functions like polyhedrons and domain repetition functions.

References :

• Shadertoy’s main page
• Inigo page 2D distance functions
• 3D distance functions

Templates and tutorials

Inigo Quilez

• Youtube
• Starter shader
• Catalog of 3D SDF

  Art of Code

• Youtube
• Ray marching starting point

  Fabrice Neyret

• Generate colors using short Hue function
• Catalog of tools code iResolution, iMouse, iDate, etc
• Catalog of widgets digits/sliders/kbd widgets - 2
• Desmos graphes
• Shadertoy unofficial

  Other sources

• Demofox blog
• Blackle blog and youtube
• Nathan Vaughn’s Blog tutorials
• Cineshader template : CineShader Lava
• Font texture explanation
• Mercury library
• port on Shadertoy of Mercury library
• MathUtils.frag of Syntopia’s Fragmentarium
• Fold space and build some Fractals (The Kaleidoscopic IFS fractals)