#Fractalfriday
I updated my #Shadertoy #fractal explorer. Link: https://www.shadertoy.com/view/33sSRf
It now supports skewing the C-plane using a quad of four draggable points. The coefficients 'a' and 'b' can now also changed by the mouse. To show the points, simply hold the space bar.
Here is a video which demonstrates that.
The formula is \(z_{n+1}=z_n^2*\frac{z_n-a}{z_n-b}+c\)
where a and b are the blue points in the video.
So I was making a random 2d map in #shadertoy, and I was trying to understand the effect of the rotation of the coordinate in a fbm 2d #noise loop, so I plugged the mouse coordinates onto the rotation angle and started to play with it to see what it did.
To my surprise, it felt like a "fire" effect, directed in one direction or the other. I feel like this could really be used to make an actual fire effect, though I'm not sure if I'm doing the rotation right at the moment...
So here is what the length of the derivatives look like on a 3D noise. I'm starting to see why it's useful for emulating terrain erosion ️
Took me several days (including so many checks like manual unrolling), but here are the 3d gradient noise derivatives¹ from iquilezles expressed with mix instead of unrolled.
Reason I did that? Well let's pretend it's for clarity and numerical stability (it's all a lie, I was just trying to understand wth was going on here).
Icosagon fractal
\( z_{n+1}=fold(z_n)^2+c \)
with 10 folds total.
Colors produced by blending multiple color gradients of escape time, distance estimation, atom domain, phase and triangle inequality average together.
After trying several broken repos/scripts, I made a Python script for rendering #ShaderToy shaders to antialiased video (or rather, image sequences):
https://github.com/keenancrane/ShaderDump
(This one will surely be broken too someday, but for now it works nicely 
)
Discovered something in @piko's #Mandelbrot workshop, which I hadn't seen before!
For each number in the complex plane c, start with x = 0, calculate x' = x^2 + c, and repeat this calculation n times!
If the result is then a+bi, draw the color (a, b, 0) for that pixel!
Here's the result for n = 1, 2, 3, ...:
Code on #Shadertoy: https://www.shadertoy.com/view/W3sSWr
Wondering if there's a continuous version?
My new Shadertoy pathtracing - all in playlist - https://www.shadertoy.com/playlist/cX3SDf
Today, I published two new #shaders on #Shadertoy. They are nothing exceptional, but they are pretty cute in their simplicity.
- andbin's Curious Geometries #1: https://www.shadertoy.com/view/w3l3Rr
- RGB Isobars Mixing: https://www.shadertoy.com/view/t3s3zr
First instance featuring #Shadertoy bridge. Subscribe to categories and follow new shaders in your #RSS reader:
https://rssbridge.flossboxin.org.in/?action=display&bridge=ShadertoyBridge&category=sotw&format=Html
Today, I published a new #shader on #Shadertoy. The code is very short, but the result is nice since I also carefully chose a pleasant color palette!
Yesterday, I published a new #shader on #Shadertoy. It’s a sort of animated “smoke cloud”.
Hi, recently, I started studying and developing simple #GLSL #shaders, “fragment shaders”, to be precise. I discovered there are various little platforms like https://www.shadertoy.com but also the less-known https://oneshader.net (and even https://editor.thebookofshaders.com) where it’s possible to develop and share “toy” shaders without the need to have ultra-advanced skills on OpenGL, WebGL, etc.
Developing these shaders is a fun (really entertaining!) activity that nicely combines #programming, #math, and #graphics. I have already made some shaders on Shadertoy, which you can see here:
https://www.shadertoy.com/user/andbin
At this time, I am unable to develop very sophisticated/stunning shaders. Anyway, my actual shaders seem nice and pleasant. Feel free to comment here (or on Shadertoy) if you like my shaders. Clearly, I am still at the beginning! Thanks.
https://www.shadertoy.com/view/ldl3W8
Classic, from 2013, by https://iquilezles.org .
Don't "optimize" conditional moves in shaders with mix()+step()
https://iquilezles.org/articles/gpuconditionals/
#ycombinator #quilez #inigo #iñigo #fractals #demoscene #computer_graphics #mathematics #rendering #demo #realtime #shader #raytracing #shadertoy #glsl #raymarching #painting_with_maths
Usually I'm thinking "wow, the real world has really good graphics", but today I spotted real-world low-quality cloud setting: upscaled low-res textures, and gaps between raymarched samples!
#shadertoy
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