rgbToHsv function

HSV rgbToHsv(TrueColor color)

Convert a TrueColor color to HSV

Implementation

//
// borrow from https://github.com/Qix-/color-convert/blob/master/conversions.js#L97
HSV rgbToHsv(TrueColor color) {
  final r = color.r / 255;
  final g = color.g / 255;
  final b = color.b / 255;
  final v = math.max(r, math.max(g, b));
  final diff = v - math.min(r, math.min(g, b));
  double diffc(double c) {
    return (v - c) / 6 / diff + 1 / 2;
  }

  var h = 0.0;
  var s = 0.0;

  if (diff != 0) {
    s = diff / v;
    final rdif = diffc(r);
    final gdif = diffc(g);
    final bdif = diffc(b);

    if (r == v) {
      h = bdif - gdif;
    } else if (g == v) {
      h = (1 / 3) + rdif - bdif;
    } else if (b == v) {
      h = (2 / 3) + gdif - rdif;
    }

    if (h < 0) {
      h += 1;
    } else if (h > 1) {
      h -= 1;
    }
  }

  return (h: h * 360, s: s * 100, v: v * 100);
}