The David Li work.

This author of adultswim.com choir uses a neural network I trained on choral pieces to generate the harmonization for your melody.
Today I will show you a good painting tool idea created by the same author: David Li.
The twitter account can be found at david li twitter. You can follow the source code on GITHUB account of this author:

Shadertoy: Shader objects with raymarching technique.

Another article about shader raymarching technique for today.
It's like the previous article created from the official video channel named The Art of Code.
The source code show how to create the basics objects like: capsule, torus, cube and cylinder.
The result of the source code of raymarching objects can be found on my account of ShaderToy website named catafest.

Shadertoy: About raymarching technique with source code.

The raymarching technique is a fairly new technique used to render realtime scenes and it is entirely computed in a screen-space shader.
The raymarching is similar to traditional raytracing (in that a ray is cast into the scene for each pixel) but is not the same technique.
How this works:
We have in a fragment shader is the position of the point we are rendering in world 3D coordinates and the view direction from the camera.
For each ray is extended by step in the view direction, until it hits something and creates a point.
This is the simple raymarching used a constant step.
The next step is the optimization calls for the use of signed distance fields.
A distance field is a function that takes in a point as input and returns the shortest distance from that point to the surface any object in the scene similar with a sphere around the hit point.
Distance fields allow us to limit how often we need to sample when marching along the ray, this is the reason of the named raymarching.
You can follow this technique on the official video channel named The Art of Code.
The result of the source code of raymarching example from this video tutorial can be found on my account of ShaderToy website.

Shadertoy: Flame 2D by catafest.

I create another shader using the shadertoy online tool.
This online tool helps users to understand the shaders theory.
All of the shaders theory is based on the math of graphics.
My example uses the basic shader for a 2D flame with minimal parameters to understand easier the math of this shader.
Let's see the source code:

// define iTime like Shader Inputs
#define time iTime
void mainImage( out vec4 fragColor, in vec2 fragCoord )
{
    // Normalized pixel coordinates (from 0 to 1)
    // vec2 uv = fragCoord/iResolution.xy;
 // create center of position of flame by xy and sized
 vec2 pos = ( fragCoord.xy / iResolution.xy )*2.0-vec2(1.,1.);
    // create flame variation 
    if(pos.y>-3.0){
  // variation by time and set up to -3.0
        // the 0.1 and 30 parameters create the variation of flame 
        // with ths sin and fract functions
        pos.y += 0.1*fract(sin(30.0*time));
 }
    // select background to black
 vec3 color = vec3(0.0,0.0,0.0);
 // set scale of flame 
 float p =.001;
    // create shape of flame (output y)
 float y = pow(abs(pos.x),3.0)/(1.0*p)*1.0;
 // create the hight of flame 
 float flame_out = length(pos+vec2(pos.x,y))*sin(0.9);
 // fix colors flame by RGB 
 if(flame_out < 0.9){
        // color for RG (red green)
  color.rg += smoothstep(0.0,0.3,0.6-flame_out);
        // fix color of flame by G (green)
  color.g /=2.4;
 }
 color += pow(color.r,1.0);
 // output color
    fragColor = vec4(color,1.0);

}

The result can be found here.