hydra sketch with custom glsl (against hydra-synth dev branch)

hydra_custom_glsl.js

synth.setFunction('josh', { type: 'src', inputs: [], glsl: `
float josh_circle(vec2 st, float cr, float cx, float cy) {
  float dx = cx-st.x, dy = cy-st.y;
  float z = cr*cr - dx*dx - dy*dy;
  return (z < 0.) ? 0. : sqrt(z)/cr;
}
vec4 josh(vec2 st){
  float z = josh_circle(st, .35, .5, .5);
  z = z-josh_circle(st, .25, .5, .5)+josh_circle(st, 0.2, 0.5, 0.5)*0.75;
  for(int i = 0; i < 10; i+=1) {
    float angle = 6.28 * float(i) / 10.;
    z = max(z, josh_circle(st, .1, cos(angle)/3.+.5, sin(angle)/3.+0.5)/2.5);
  }
  return vec4(z, z, z, 1.);
}`})

josh().contrast(1.5).out()
const π = Math.PI
osc(π,1/π,10)
  .diff(
    josh()
    .rotate(0,3)
    .repeat(4)
    .contrast(1.5)
    .rotate(0,0.5)
  )
  .mult(
    josh()
    .contrast(1.5)
    .mult(voronoi(150,1),0.15)
    .rotate(0,-.25)
    .scrollX(0.1)
    .rotate(0,-0.75)
  )
  .out()