anchor.diff:    return [h, s, v];
   }
   
  -hsv_irga(List<double> hsv) {
  +hsv_irgba(List<double> hsv) {
   
     var h = hsv[0] * 6;
     var s = hsv[1];
  
positive.code: import 'dart:math' as math;
  import 'package:vector_math/vector_math.dart';
  
  irgba_r255(int v) => ((v & 0xff000000) >> 24);
  irgba_r1(int v) => ((v & 0xff000000) >> 24) / 255.0;
  irgba_g255(int v) => ((v & 0x00ff0000) >> 16);
  irgba_g1(int v) => ((v & 0x00ff0000) >> 16) / 255.0;
  irgba_b255(int v) => ((v & 0x0000ff00) >> 8);
  irgba_b1(int v) => ((v & 0x0000ff00) >> 8) / 255.0;
  irgba_a255(int v) => ((v & 0x000000ff));
  irgba_a1(int v) => ((v & 0x000000ff)) / 255.0;
  
  int rgb1_irgba(double r, double g, double b) {
    return 0x000000ff | ((r * 255).toInt() << 24) | ((g * 255).toInt() << 16) | ((b * 255).toInt() << 8);
  
negative.code: 
  
  // Converts an rgba (int) color value to [h, s, l] each value in [0.0, 1.0].
  List<double> irgba_hsl(int c) {
    var r = irgba_r1(c);
    var g = irgba_g1(c);
    var b = irgba_r1(c);
  
    var max = math.max(math.max(r, g), b);
    var min = math.min(math.min(r, g), b);
  