Random color

color.js

// http://martin.ankerl.com/2009/12/09/how-to-create-random-colors-programmatically/


function hsv_to_rgb(h, s = 0.5, v = 0.95) {
  
  let _h = ( Math.random() + 0.618033988749895 ) % 1;
  
  h = h || _h;

  let h_i = Number((h*6).toFixed(0));
  let f = h*6 - h_i;
  let p = v * (1 - s);
  let q = v * (1 - f*s);
  let t = v * (1 - (1 - f) * s);
  let r=0,g=0,b=0;
  
  if(h_i === 0) {
    [r, g, b] = [v, t, p]
  }
  else if(h_i === 1) {
    [r, g, b] = [q, v, p]
  }
  else if(h_i === 2) {
    [r, g, b] = [p, v, t]
  }
  else if(h_i === 3) {
    [r, g, b] = [p, q, v]
  }
  else if(h_i === 4) {
    [r, g, b] = [t, p, v]
  }
  else if(h_i === 5) {
    [r, g, b] = [v, p, q]
  }
  
  return `rgb(${(r*256).toFixed(0)},${(g*256).toFixed(0)},${(b*256).toFixed(0)})`;
}