dev5/psychlops/extension/standard/CIEColor.cs

   1 using System;\r
   2 \r
   3 namespace Psychlops\r
   4 {\r
   5         namespace ColorSpaces\r
   6         {\r
   7                 public struct HSV\r
   8                 {\r
   9                         public double H, S, V, A;\r
  10 \r
  11                         public Color toRGB()\r
  12                         {\r
  13                                 if (S == 0.0) return new Color(V, V, V, A);\r
  14                                 int hi = (int)Math.floor(H/60.0);\r
  15                                 double f = (H / 60.0) - (double)hi,\r
  16                                            p = V*(1.0-S),\r
  17                                            q = V*(1.0-f*S),\r
  18                                            t = V*(1.0-(1.0-f)*S);\r
  19                                 if (hi == 0) { return new Color(V, t, p, A); }\r
  20                                 else if (hi == 1) { return new Color(q, V, p, A); }\r
  21                                 else if (hi == 2) { return new Color(p, V, t, A); }\r
  22                                 else if (hi == 3) { return new Color(p, q, V, A); }\r
  23                                 else if (hi == 4) { return new Color(t, p, V, A); }\r
  24                                 else if (hi == 5) { return new Color(V, p, q, A); }\r
  25                                 else return Color.transparent;\r
  26                         }\r
  27 \r
  28                         public void fromRGB(Color o) {\r
  29                                 double MAX = Math.max(Math.max(o.r, o.g), o.b);\r
  30                                 double MIN = Math.min(Math.min(o.r, o.g), o.b);\r
  31                                 double h;\r
  32                                 if(MAX==MIN) { h=0.0; }\r
  33                                 else if(o.r>o.g && o.r>o.b) { h=60.0*(o.g-o.b)/(MAX-MIN)+360.0; }\r
  34                                 else if(o.g>o.b) { h=60.0*(o.b-o.r)/(MAX-MIN)+120.0; }\r
  35                                 else { h=60.0*(o.r-o.g)/(MAX-MIN)+240.0; }\r
  36                                 h = Math.mod(h, 360.0);\r
  37                                 double v = MAX, s;\r
  38                                 if(MAX==MIN) { s=0.0; } else { s=(MAX-MIN)/MAX; }\r
  39                                 H = h;\r
  40                                 S = s;\r
  41                                 V = v;\r
  42                                 A = o.a;\r
  43                         }\r
  44                 }\r
  45 \r
  46                 /*\r
  47                  * CIE 1931\r
  48                  * R: 700 nm\r
  49                  * G: 546.1 nm\r
  50                  * B: 435.8 nm\r
  51                  * White Point: Illuminant E\r
  52                  */\r
  53                 public struct CIERGB\r
  54                 {\r
  55                         public double R, G, B;\r
  56 \r
  57                         public CIEXYZ convertToCIEXYZ()\r
  58                         {\r
  59                                 double[,] b =\r
  60                         { \r
  61                                 { 0.49, 0.31, 0.20 },\r
  62                                 { 0.17697, 0.81240, 0.01063 },\r
  63                                 { 0.00, 0.01, 0.99 }\r
  64                         };\r
  65 \r
  66                                 CIEXYZ v;\r
  67 \r
  68                                 v.X = b[0, 0] * R + b[0, 1] * G + b[0, 2] * B;\r
  69                                 v.Y = b[1, 0] * R + b[1, 1] * G + b[1, 2] * B;\r
  70                                 v.Z = b[2, 0] * R + b[2, 1] * G + b[2, 2] * B;\r
  71 \r
  72                                 return v;\r
  73                         }\r
  74                 }\r
  75 \r
  76                 /*\r
  77                  * CIE 1931\r
  78                  */\r
  79                 public struct CIEXYZ\r
  80                 {\r
  81                         public double X, Y, Z;\r
  82 \r
  83                         public CIExyY convertToCIExyY()\r
  84                         {\r
  85                                 CIExyY v;\r
  86 \r
  87                                 double denominator = X + Y + Z;\r
  88                                 v.x = X / denominator;\r
  89                                 v.y = Y / denominator;\r
  90                                 v.Y = Y;\r
  91 \r
  92                                 return v;\r
  93                         }\r
  94                 }\r
  95 \r
  96                 public struct CIExyY\r
  97                 {\r
  98                         public double x, y, Y;\r
  99 \r
 100                         public CIEXYZ convertToCIEXYZ()\r
 101                         {\r
 102                                 CIEXYZ v;\r
 103 \r
 104                                 v.X = Y / y * x;\r
 105                                 v.Y = Y;\r
 106                                 v.Z = Y / y * (1 - x - y);\r
 107 \r
 108                                 return v;\r
 109                         }\r
 110 \r
 111                         // Yn = 1.0 when RGB of white point is { 1, 1, 1 }\r
 112                         public CIELuv convertToCIELuv(double Yn = 1.0)\r
 113                         {\r
 114 \r
 115                                 CIELuv v;\r
 116 \r
 117                                 double denominator = (-2 * x + 12 * y + 3);\r
 118                                 double up = 4 * x / denominator;\r
 119                                 double vp = 9 * y / denominator;\r
 120 \r
 121                                 double Yd = Y / Yn;\r
 122                                 v.L = Yd > System.Math.Pow(6 / 29, 3) ? 116 * System.Math.Pow(Yd, 3) : System.Math.Pow(29 / 3, 3) * Yd;\r
 123                                 v.u = 13 * v.L * (up - 0.2009);\r
 124                                 v.v = 13 * v.L * (vp - 0.4610);\r
 125 \r
 126                                 return v;\r
 127                         }\r
 128                 }\r
 129 \r
 130                 /* L*u*v*\r
 131                  * CIE 1976\r
 132                  * standard illuminant C\r
 133                  */\r
 134                 public struct CIELuv\r
 135                 {\r
 136                         public double L, u, v;\r
 137 \r
 138                 }\r
 139 \r
 140                 public struct CIELab\r
 141                 {\r
 142                         public double L, a, b;\r
 143 \r
 144                 }\r
 145 \r
 146         }\r
 147 }