storm.sksl

uniform float3 iResolution;      // Viewport resolution (pixels)
uniform float  iTime;            // Shader playback time (s)
uniform float4 iMouse;           // Mouse drag pos=.xy Click pos=.zw (pixels)
uniform float3 iImage1Resolution; // iImage1 resolution (pixels)
uniform shader iImage1;          // An input image.

// Source: @zozuar https://twitter.com/zozuar/status/1492217553103503363

vec3 hsv(float h, float s, float v){
    vec4 t = vec4(1.0, 2.0 / 3.0, 1.0 / 3.0, 3.0);
    vec3 p = abs(fract(vec3(h) + t.xyz) * 6.0 - vec3(t.w));
    return v * mix(vec3(t.x), clamp(p - vec3(t.x), 0.0, 1.0), s);
}

vec4 main(vec2 FC) {
  float e=0,R=0,t=iTime,s;
  vec2 r = iResolution.xy;
  vec3 q=vec3(0,0,-1), p, d=vec3((FC.xy-.5*r)/r.y,.7);
  vec4 o=vec4(0);
  for(float i=0;i<100;++i) {
    o.rgb+=hsv(.1,e*.4,e/1e2)+.005;
    p=q+=d*max(e,.02)*R*.3;
    float py = (p.x == 0 && p.y == 0) ? 1 : p.y;
    p=vec3(log(R=length(p))-t,e=asin(-p.z/R)-1.,atan(p.x,py)+t/3.);
    s=1;
    for(int z=1; z<=9; ++z) {
      e+=cos(dot(sin(p*s),cos(p.zxy*s)))/s;
      s+=s;
    }
    i>50.?d/=-d:d;
  }
  return vec4(o.rgb, 1);
}