#shadertoy

[chriskotiesen]

mfw I'm playing around with shader programming again

[notsogreeeen]

King Crimson Aura

Okay, my initial approach of creating noise then applying color wasn't very intelligent, but once I rewrote it to mix between an inner and outer color it worked wonders!

A lot of my generative functions are actually Lygia's! (now that I've found the library) I'm loving the ease of just ctrl+c, ctrl+v then calling the functions!

here's the shader for those who want, it's not much to go in depth for though, so no writeup ;-;

Shadertoy

[ompuco]

[agatedragongames]

In this tutorial you will learn how to code a sunburst effect inside a shader, using scanlines and polar coordinates. You will learn how to code the effect using the web based shader editor called Shadertoy.

Shader Tutorial: Coding a Sunburst Effect

In this tutorial you will learn how to code a sunburst effect inside a shader, using scanlines and polar coordinates. You will learn how to

[aer0wave]

accidental glitch art while programming a pathtracer

[sublingual-art]

Recent coding practice:

1 & 2: Messing around in shadertoy

3 & 4: Got subdivision working in my stick generator and branching almost-working, though it strangely fails after one iteration out from the main branch.

[blake447]

Dragon Curves

This is one of my personal favorite fractals, the Harter-Heighway Dragon Curve, featured in the original Jurrassic park book shown skipping a few steps at a time, unpredictably evolving into this shape here to highlight the chaotic but organized mess of nature we struggle to predict and understand. This is among the friends I am most deeply and intimately familiar with. I started playing around with these based off an old ViHart video explaining how to make them in terms of squiggles and folding papers

My traditional method has always been to take a sequence, reverse it, and add one, rolling over when you hit 4. Example 0 01 01 21 01 21 23 21 01 21 23 21 23 03 23 21

If you change each number into a direction, 0 being right, 1 being up, and so on, then follow that path along the sequence you will also get a dragon curve. There are so many wonderful ways to construct these

However, here’s my favorite

This is my Dragon Curve *unity shader* that I wrote. It comes with an editor script that you can use to bake it into a texture, since the process is a bit heavy. Why is this so special you ask? Well it comes down to the fact that this is running in real time, in parallel. See algorithms have two main kinds of families, parallel and serial. A serial algorithm goes step by step, like taking a math test alone. A parallel algorithm runs side by side, like everyone doing one problem on the test. Its much faster, but they aren’t allowed to talk to each other so if the same problem shows up twice, or if a second problem relies on the answer to the first, its much more difficult. This is why dragon curves are hard to parallelize. You take the sequence *before* and reverse / increase. You take the segments *from the last step* and fold them again. You fold the paper *back over itself* referencing previous work. This problem is about as serializable as it comes. So how do you parallelize? Will, you change your perspective

See instead of trying to split everyone up to try to *create* a dragon curve, you give every pixel a job to decide *is it on* a dragon curve. By rotating the space itself in alternating grid patterns you can twist a dragon curve down into a single line. If your point in space ends up on the line, then it was on the dragon curve! Furthermore, the direction it turns due to how the grids line up actually encodes how far along the dragon curve it was in binary (left being a 0, right being a 1), so by keeping track of that and converting it to decimal we can give subtle coloration to points on one dragon curve from 0-2^n, and clip out anything that isn’t on it. As far as I know, I’m the only person to have implemented it this way and it might be a straight up novel algorithm, which I’m super proud of!

And this is how I create these beautiful Dragon Curve Plaids. Since we’re warping the space itself, we do our twisting to collapse it, put some little checker and strip patterns on that space, color it a little bit based on the direction, and unwind it again to twist the pattern into the dragon curve instead of the space. I also have a live demonstration of the algorithm up on shadertoy, though its a very outdated implementation and not well optimized. Here’s one thats animated, and here’s a newer one that tracks the folds in binary. They are rendering in real time, so potatos beware. Finally, here’s a zoom on one of my youtube accounts of a 41st iteration dragon curve zoom, twice as many iterations in realtime as my old laptop could do in 20 minutes. Computer Science enthusiasts will realize how mind boggling cool that is, even if its is entirely useless.

[alexhohlov]

See full project on behance.net/veaone