In october 2012, Andrew Baldwing started publishing a series on articles on his blog (http://thndl.com/) about GLSL (OpenGL Shading Language). 

In Andrew's own words: “When I first heard about shaders, I have to admit they sounded like scary arcane magic that I would never be able get to grips with. But it turned out that the magic was mostly just boilerplate setup code you needed to get started, and once you got past that they were actually quite simple.”

His blog includes a GLSL interpreter that gets the “boilerplate” code out of the way and lets you experiment with the core instructions of the shader. I thought it would be interesting though to see if these examples could be ported to Processing so here they are.

The sketch folder, includes a glsl file (with explanatory comments) that regroups all the shaders from the ThNdl articles published so far.

The sketch and shader file are intended to accompany the reading of the tutorials. You will need Processing 2.0b6 or superior.

Note: If you want to edit your shader files in the same editor as your .pde, you should have a look at Sublime Text 2 with this Processing package installed (https://github.com/b-g/processing-sublime).

Note for mac users: Xcode also does syntax coloring for GLSL.

Many thanks to Adrew Baldwing and to Andres Colubri for his work on shaders in Processing 2.0 and his articles that were a lot of help (http://codeanticode.wordpress.com/).

Happy shading!

See original discussion on the Processing forums: https://forum.processing.org/topic/thndl-shader-tutorial-in-processing-get-started-with-glsl