@vaadin-component-factory/vcf-network/src/utils/pSBC.js

Hierarchical network visualizing web component

// Shade, Blend and Convert a Web Color
// https://github.com/PimpTrizkit/PJs/wiki/12.-Shade,-Blend-and-Convert-a-Web-Color-(pSBC.js)

export function pSBC(p, c0, c1, l) {
  let r;
  let g;
  let b;
  let P;
  let f;
  let t;
  let h;
  let a = typeof c1 == 'string';
  const i = parseInt;
  const m = Math.round;
  if (typeof p != 'number' || p < -1 || p > 1 || typeof c0 != 'string' || (c0[0] != 'r' && c0[0] != '#') || (c1 && !a))
    return null;
  if (!this._pSBCr)
    this._pSBCr = d => {
      let n = d.length;
      const x = {};
      if (n > 9) {
        ([r, g, b, a] = d = d.split(',')), (n = d.length);
        if (n < 3 || n > 4) return null;
        (x.r = i(r[3] == 'a' ? r.slice(5) : r.slice(4))), (x.g = i(g)), (x.b = i(b)), (x.a = a ? parseFloat(a) : -1);
      } else {
        if (n == 8 || n == 6 || n < 4) return null;
        if (n < 6) d = '#' + d[1] + d[1] + d[2] + d[2] + d[3] + d[3] + (n > 4 ? d[4] + d[4] : '');
        d = i(d.slice(1), 16);
        if (n == 9 || n == 5)
          (x.r = (d >> 24) & 255), (x.g = (d >> 16) & 255), (x.b = (d >> 8) & 255), (x.a = m((d & 255) / 0.255) / 1000);
        else (x.r = d >> 16), (x.g = (d >> 8) & 255), (x.b = d & 255), (x.a = -1);
      }
      return x;
    };
  (h = c0.length > 9),
    (h = a ? (c1.length > 9 ? true : c1 == 'c' ? !h : false) : h),
    (f = this._pSBCr(c0)),
    (P = p < 0),
    (t = c1 && c1 != 'c' ? this._pSBCr(c1) : P ? { r: 0, g: 0, b: 0, a: -1 } : { r: 255, g: 255, b: 255, a: -1 }),
    (p = P ? p * -1 : p),
    (P = 1 - p);
  if (!f || !t) return null;
  if (l) (r = m(P * f.r + p * t.r)), (g = m(P * f.g + p * t.g)), (b = m(P * f.b + p * t.b));
  else
    (r = m((P * f.r ** 2 + p * t.r ** 2) ** 0.5)),
      (g = m((P * f.g ** 2 + p * t.g ** 2) ** 0.5)),
      (b = m((P * f.b ** 2 + p * t.b ** 2) ** 0.5));
  (a = f.a), (t = t.a), (f = a >= 0 || t >= 0), (a = f ? (a < 0 ? t : t < 0 ? a : a * P + t * p) : 0);
  if (h) return 'rgb' + (f ? 'a(' : '(') + r + ',' + g + ',' + b + (f ? ',' + m(a * 1000) / 1000 : '') + ')';
  else
    return (
      '#' +
      (4294967296 + r * 16777216 + g * 65536 + b * 256 + (f ? m(a * 255) : 0)).toString(16).slice(1, f ? undefined : -2)
    );
}