ColorGenerator Class — react Architecture

Source Code

packages/react-devtools-timeline/src/content-views/utils/colors.js lines 70–113

export class ColorGenerator {
  _hueSpace: ColorSpace;
  _satSpace: ColorSpace;
  _lightnessSpace: ColorSpace;
  _alphaSpace: ColorSpace;
  _colors: Map<string, HslaColor>;

  constructor(
    hueSpace?: ColorSpace,
    satSpace?: ColorSpace,
    lightnessSpace?: ColorSpace,
    alphaSpace?: ColorSpace,
  ) {
    this._hueSpace = hueSpace || {min: 0, max: 360};
    this._satSpace = satSpace || 67;
    this._lightnessSpace = lightnessSpace || 80;
    this._alphaSpace = alphaSpace || 1;
    this._colors = new Map();
  }

  setColorForID(id: string, color: HslaColor) {
    this._colors.set(id, color);
  }

  colorForID(id: string): HslaColor {
    const cachedColor = this._colors.get(id);
    if (cachedColor) {
      return cachedColor;
    }
    const color = this._generateColorForID(id);
    this._colors.set(id, color);
    return color;
  }

  _generateColorForID(id: string): HslaColor {
    const hash = hashCode(id);
    return {
      h: indexToValueInSpace(hash, this._hueSpace),
      s: indexToValueInSpace(hash >> 8, this._satSpace),
      l: indexToValueInSpace(hash >> 16, this._lightnessSpace),
      a: indexToValueInSpace(hash >> 24, this._alphaSpace),
    };
  }
}