color.C

/*
 * This file is part of the "Archon" framework.
 * (http://files3d.sourceforge.net)
 *
 * Copyright © 2002 by Kristian Spangsege and Brian Kristiansen.
 *
 * Permission to use, copy, modify, and distribute this software and
 * its documentation under the terms of the GNU General Public License is
 * hereby granted. No representations are made about the suitability of
 * this software for any purpose. It is provided "as is" without express
 * or implied warranty. See the GNU General Public License
 * (http://www.gnu.org/copyleft/gpl.html) for more details.
 *
 * The characters in this file are ISO8859-1 encoded.
 *
 * The documentation in this file is in "Doxygen" style
 * (http://www.doxygen.org).
 */

#include <iostream>

#include <archon/math/functions.H>

#include <archon/util/color.H>

namespace Archon
{
  namespace Utilities
  {
    namespace Color
    {
      Vector3 convertRGBtoHSV(Vector3 c)
      {
        double v = c.max();
        double d = v - c.min();
        if(d == 0) return Vector3(0, 0, v); // Achromatic
        double h =
          (v == c[0] ? (c[1] - c[2]) / d :
           v == c[1] ? 2 + (c[2] - c[0]) / d :
           4 + (c[0] - c[1]) / d) * 60;
        if(h<0) h += 360;
        return Vector3(h, d/v, v);
      }

      Vector3 convertHSVtoRGB(Vector3 c)
      {
        if(c[1] == 0)
          return Vector3(c[2], c[2], c[2]); // Achromatic

        double h = modulo<double>(c[0], 360)/60;
        int i = static_cast<int>(h);
        double f = h - i;
        double c0 = c[2] * (1 - c[1]);
        double c1 = c[2] * (1 - (c[1] * f));
        double c2 = c[2] * (1 - (c[1] * (1 - f)));
        switch(i)
        {
        case 0: return Vector3(c[2], c2, c0);
        case 1: return Vector3(c1, c[2], c0);
        case 2: return Vector3(c0, c[2], c2);
        case 3: return Vector3(c0, c1, c[2]);
        case 4: return Vector3(c2, c0, c[2]);
        default: return Vector3(c[2], c0, c1);
        }
      }

      Vector3 interp(double x, double x1, double x2, Vector3 y1, Vector3 y2)
      {
        Vector3 z1 = convertRGBtoHSV(y1);
        Vector3 z2 = convertRGBtoHSV(y2);

        // Pick a sensible value for hue when it is arbitrary/undefined
        if(z1[1] == 0) z1[0] = z2[0];
        else if(z2[1] == 0) z2[0] = z1[0];

        // Pick a sensible value for saturation when it is arbitrary/undefined
        if(z1[2] == 0) z1[1] = z2[1];
        else if(z2[2] == 0) z2[1] = z1[1];

        // Pick the shortest hue arc
        double d = z2[0] - z1[0];
        if(d < -180) z2[0] += 360;
        else if(d > 180) z1[0] += 360;

        return convertHSVtoRGB(linInterp(x, x1, x2, z1, z2));
      }

      const Vector3 aliceblue(240/255.0, 248/255.0, 255/255.0);
      const Vector3 antiquewhite(250/255.0, 235/255.0, 215/255.0);
      const Vector3 aqua(0/255.0, 255/255.0, 255/255.0);
      const Vector3 aquamarine(127/255.0, 255/255.0, 212/255.0);
      const Vector3 azure(240/255.0, 255/255.0, 255/255.0);
      const Vector3 beige(245/255.0, 245/255.0, 220/255.0);
      const Vector3 bisque(255/255.0, 228/255.0, 196/255.0);
      const Vector3 black(0/255.0, 0/255.0, 0/255.0);
      const Vector3 blanchedalmond(255/255.0, 235/255.0, 205/255.0);
      const Vector3 blue(0/255.0, 0/255.0, 255/255.0);
      const Vector3 blueviolet(138/255.0, 43/255.0, 226/255.0);
      const Vector3 brown(165/255.0, 42/255.0, 42/255.0);
      const Vector3 burlywood(222/255.0, 184/255.0, 135/255.0);
      const Vector3 cadetblue(95/255.0, 158/255.0, 160/255.0);
      const Vector3 chartreuse(127/255.0, 255/255.0, 0/255.0);
      const Vector3 chocolate(210/255.0, 105/255.0, 30/255.0);
      const Vector3 coral(255/255.0, 127/255.0, 80/255.0);
      const Vector3 cornflowerblue(100/255.0, 149/255.0, 237/255.0);
      const Vector3 cornsilk(255/255.0, 248/255.0, 220/255.0);
      const Vector3 crimson(220/255.0, 20/255.0, 54/255.0);
      const Vector3 cyan(0/255.0, 255/255.0, 255/255.0);
      const Vector3 darkblue(0/255.0, 0/255.0, 139/255.0);
      const Vector3 darkcyan(0/255.0, 139/255.0, 139/255.0);
      const Vector3 darkgoldenrod(184/255.0, 134/255.0, 11/255.0);
      const Vector3 darkgray(169/255.0, 169/255.0, 169/255.0);
      const Vector3 darkgreen(0/255.0, 100/255.0, 0/255.0);
      const Vector3 darkkhaki(189/255.0, 183/255.0, 107/255.0);
      const Vector3 darkmagenta(139/255.0, 0/255.0, 139/255.0);
      const Vector3 darkolivegreen(85/255.0, 107/255.0, 47/255.0);
      const Vector3 darkorange(255/255.0, 140/255.0, 0/255.0);
      const Vector3 darkorchid(153/255.0, 50/255.0, 204/255.0);
      const Vector3 darkred(139/255.0, 0/255.0, 0/255.0);
      const Vector3 darksalmon(233/255.0, 150/255.0, 122/255.0);
      const Vector3 darkseagreen(143/255.0, 188/255.0, 143/255.0);
      const Vector3 darkslateblue(72/255.0, 61/255.0, 139/255.0);
      const Vector3 darkslategray(47/255.0, 79/255.0, 79/255.0);
      const Vector3 darkturquoise(0/255.0, 206/255.0, 209/255.0);
      const Vector3 darkviolet(148/255.0, 0/255.0, 211/255.0);
      const Vector3 deeppink(255/255.0, 20/255.0, 147/255.0);
      const Vector3 deepskyblue(0/255.0, 191/255.0, 255/255.0);
      const Vector3 dimgray(105/255.0, 105/255.0, 105/255.0);
      const Vector3 dodgerblue(30/255.0, 144/255.0, 255/255.0);
      const Vector3 firebrick(178/255.0, 34/255.0, 34/255.0);
      const Vector3 floralwhite(255/255.0, 250/255.0, 240/255.0);
      const Vector3 forestgreen(34/255.0, 139/255.0, 34/255.0);
      const Vector3 fuchsia(255/255.0, 0/255.0, 255/255.0);
      const Vector3 gainsboro(220/255.0, 220/255.0, 220/255.0);
      const Vector3 ghostwhite(248/255.0, 248/255.0, 255/255.0);
      const Vector3 gold(255/255.0, 215/255.0, 0/255.0);
      const Vector3 goldenrod(218/255.0, 165/255.0, 32/255.0);
      const Vector3 gray(128/255.0, 128/255.0, 128/255.0);
      const Vector3 green(0/255.0, 128/255.0, 0/255.0);
      const Vector3 greenyellow(173/255.0, 255/255.0, 47/255.0);
      const Vector3 honeydew(240/255.0, 255/255.0, 240/255.0);
      const Vector3 hotpink(255/255.0, 105/255.0, 180/255.0);
      const Vector3 indianred(205/255.0, 92/255.0, 92/255.0);
      const Vector3 indigo(75/255.0, 0/255.0, 130/255.0);
      const Vector3 ivory(255/255.0, 255/255.0, 240/255.0);
      const Vector3 khaki(240/255.0, 230/255.0, 140/255.0);
      const Vector3 lavender(230/255.0, 230/255.0, 250/255.0);
      const Vector3 lavenderblush(255/255.0, 240/255.0, 245/255.0);
      const Vector3 lawngreen(124/255.0, 252/255.0, 0/255.0);
      const Vector3 lemonchiffon(255/255.0, 250/255.0, 205/255.0);
      const Vector3 lightblue(173/255.0, 216/255.0, 230/255.0);
      const Vector3 lightcoral(240/255.0, 128/255.0, 128/255.0);
      const Vector3 lightcyan(224/255.0, 255/255.0, 255/255.0);
      const Vector3 lightgoldenrodyellow(250/255.0, 250/255.0, 210/255.0);
      const Vector3 lightgreen(144/255.0, 238/255.0, 144/255.0);
      const Vector3 lightgrey(211/255.0, 211/255.0, 211/255.0);
      const Vector3 lightpink(255/255.0, 182/255.0, 193/255.0);
      const Vector3 lightsalmon(255/255.0, 160/255.0, 122/255.0);
      const Vector3 lightseagreen(32/255.0, 178/255.0, 170/255.0);
      const Vector3 lightskyblue(135/255.0, 206/255.0, 250/255.0);
      const Vector3 lightslategray(119/255.0, 136/255.0, 153/255.0);
      const Vector3 lightsteelblue(176/255.0, 196/255.0, 222/255.0);
      const Vector3 lightyellow(255/255.0, 255/255.0, 224/255.0);
      const Vector3 lime(0/255.0, 255/255.0, 0/255.0);
      const Vector3 limegreen(50/255.0, 205/255.0, 50/255.0);
      const Vector3 linen(250/255.0, 240/255.0, 230/255.0);
      const Vector3 magenta(255/255.0, 0/255.0, 255/255.0);
      const Vector3 maroon(128/255.0, 0/255.0, 0/255.0);
      const Vector3 mediumaquamarine(102/255.0, 205/255.0, 170/255.0);
      const Vector3 mediumblue(0/255.0, 0/255.0, 205/255.0);
      const Vector3 mediumorchid(186/255.0, 85/255.0, 211/255.0);
      const Vector3 mediumpurple(147/255.0, 112/255.0, 219/255.0);
      const Vector3 mediumseagreen(60/255.0, 179/255.0, 113/255.0);
      const Vector3 mediumslateblue(123/255.0, 104/255.0, 238/255.0);
      const Vector3 mediumspringgreen(0/255.0, 250/255.0, 154/255.0);
      const Vector3 mediumturquoise(72/255.0, 209/255.0, 204/255.0);
      const Vector3 mediumvioletred(199/255.0, 21/255.0, 133/255.0);
      const Vector3 midnightblue(25/255.0, 25/255.0, 112/255.0);
      const Vector3 mintcream(245/255.0, 255/255.0, 250/255.0);
      const Vector3 mistyrose(255/255.0, 228/255.0, 225/255.0);
      const Vector3 moccasin(255/255.0, 228/255.0, 181/255.0);
      const Vector3 navajowhite(255/255.0, 222/255.0, 173/255.0);
      const Vector3 navy(0/255.0, 0/255.0, 128/255.0);
      const Vector3 oldlace(253/255.0, 245/255.0, 230/255.0);
      const Vector3 olive(128/255.0, 128/255.0, 0/255.0);
      const Vector3 olivedrab(107/255.0, 142/255.0, 35/255.0);
      const Vector3 orange(255/255.0, 165/255.0, 0/255.0);
      const Vector3 orangered(255/255.0, 69/255.0, 0/255.0);
      const Vector3 orchid(218/255.0, 112/255.0, 214/255.0);
      const Vector3 palegoldenrod(238/255.0, 232/255.0, 170/255.0);
      const Vector3 palegreen(152/255.0, 251/255.0, 152/255.0);
      const Vector3 paleturquoise(175/255.0, 238/255.0, 238/255.0);
      const Vector3 palevioletred(219/255.0, 112/255.0, 147/255.0);
      const Vector3 papayawhip(255/255.0, 239/255.0, 213/255.0);
      const Vector3 peachpuff(255/255.0, 218/255.0, 185/255.0);
      const Vector3 peru(205/255.0, 133/255.0, 63/255.0);
      const Vector3 pink(255/255.0, 192/255.0, 203/255.0);
      const Vector3 plum(221/255.0, 160/255.0, 221/255.0);
      const Vector3 powderblue(176/255.0, 224/255.0, 230/255.0);
      const Vector3 purple(128/255.0, 0/255.0, 128/255.0);
      const Vector3 red(255/255.0, 0/255.0, 0/255.0);
      const Vector3 rosybrown(188/255.0, 143/255.0, 143/255.0);
      const Vector3 royalblue(65/255.0, 105/255.0, 225/255.0);
      const Vector3 saddlebrown(139/255.0, 69/255.0, 19/255.0);
      const Vector3 salmon(250/255.0, 128/255.0, 114/255.0);
      const Vector3 sandybrown(244/255.0, 164/255.0, 96/255.0);
      const Vector3 seagreen(46/255.0, 139/255.0, 87/255.0);
      const Vector3 seashell(255/255.0, 245/255.0, 238/255.0);
      const Vector3 sienna(160/255.0, 82/255.0, 45/255.0);
      const Vector3 silver(192/255.0, 192/255.0, 192/255.0);
      const Vector3 skyblue(135/255.0, 206/255.0, 235/255.0);
      const Vector3 slateblue(106/255.0, 90/255.0, 205/255.0);
      const Vector3 slategray(112/255.0, 128/255.0, 144/255.0);
      const Vector3 snow(255/255.0, 250/255.0, 250/255.0);
      const Vector3 springgreen(0/255.0, 255/255.0, 127/255.0);
      const Vector3 steelblue(70/255.0, 130/255.0, 180/255.0);
      const Vector3 tan(210/255.0, 180/255.0, 140/255.0);
      const Vector3 teal(0/255.0, 128/255.0, 128/255.0);
      const Vector3 thistle(216/255.0, 191/255.0, 216/255.0);
      const Vector3 tomato(255/255.0, 99/255.0, 71/255.0);
      const Vector3 turquoise(64/255.0, 224/255.0, 208/255.0);
      const Vector3 violet(238/255.0, 130/255.0, 238/255.0);
      const Vector3 wheat(245/255.0, 222/255.0, 179/255.0);
      const Vector3 white(255/255.0, 255/255.0, 255/255.0);
      const Vector3 whitesmoke(245/255.0, 245/255.0, 245/255.0);
      const Vector3 yellow(255/255.0, 255/255.0, 0/255.0);
      const Vector3 yellowgreen(154/255.0, 205/255.0, 50/255.0);
    }
  }
}

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