atoMeow

Blue noise image stippling in Processing (requires GPU)

Many Twitter friends are talking about sample code, and I think Processing is probably the best platform to write a demo. This demo is created for coders who are familiar with this awesome creative coding platform. You may quickly modify the code to work for video or to stipple your own Procssing drawings by turning them into PImage and run the simulation. This demo code also serves as a reference implementation of my article Blue noise sampling using an N-body simulation-based method. If you are interested in 2.5D, you may mod the code to achieve what I discussed in this artist friendly article.

This code has been tested on Processing 3.5.4 (Windows 10 (nVIDIA GPU) and MacOS Big Sur (MBP 2016 with Intel Iris)).


Original atoMeow Moving Stipples on Twitter	My Fav. Hokusai

QuickStart

Many sim-essential global variables are highlighted and documented, please study the usual setup() and draw() functions for how the simulation code works. You may use any PImage as Field image (Electrostatic field) and feed it to void updateField(

) (line #203) function; it will be automatically resized to fit the size int simXY; (line #47). The maximum number of dots to simulate is determined by int bufXY; (line #46), please note that they both shall raise the GPU memory demand. (I find 8192 points reasonable for most laptops). The function void sim(int n); is designed to run a number of steps before return such that you could sub-sample easily the outputs or for creating your image sequence stippling (Yes! Processing Video library reads frames into Processing as PImage ? (I recall …). I believe you will do your homework!

Have Fun! If you have never coded with Processing, you are missing something very important !! Go https://www.processing.org/ (20 Years Anniversary) and you will create your first sketch before you finish your Latte.

Making-Of Note

I have not used Processing for a long time …. so my know-how is rusty; I was looking for the possibility of using compute shaders (render to multiple tragets) but no luck and no time. Please enlighten me if there are better ways, my Twitter @artixels. Anyways, so I actually made a Dirty Hack of encoding 2x Half-precision (I am a VFX guy) float (per-particle pos(x,y), vel(x,y) and acc(x,y)) to fit into a color of Processing. This allows results to be captured using .copy() of PGraphics and pipe them down to next shader via a PImage. I am glad the round-tripping was working quickly too, thanks to the awesome Java function I found in Stackoverflow by x4u. Another good 16-bit Half float by Martijn Courteaux for the range 0.0 – 1.0 (no sign) is also very attractive, it should be great for next creative coding project.