js2/mwEmbed/libClipEdit/pixastic-lib/actions/hsl.js

   1 /*
   2  * Pixastic Lib - HSL Adjust  - v0.1.0
   3  * Copyright (c) 2008 Jacob Seidelin, jseidelin@nihilogic.dk, http://blog.nihilogic.dk/
   4  * MIT License [http://www.opensource.org/licenses/mit-license.php]
   5  */
   6
   7 Pixastic.Actions.hsl = {
   8         process : function(params) {
   9
  10                 var hue = parseInt(params.options.hue,10)||0;
  11                 var saturation = (parseInt(params.options.saturation,10)||0) / 100;
  12                 var lightness = (parseInt(params.options.lightness,10)||0) / 100;
  13
  14
  15                 // this seems to give the same result as Photoshop
  16                 if (saturation < 0) {
  17                         var satMul = 1+saturation;
  18                 } else {
  19                         var satMul = 1+saturation*2;
  20                 }
  21
  22                 hue = (hue%360) / 360;
  23                 var hue6 = hue * 6;
  24
  25                 var rgbDiv = 1 / 255;
  26
  27                 var light255 = lightness * 255;
  28                 var lightp1 = 1 + lightness;
  29                 var lightm1 = 1 - lightness;
  30                 if (Pixastic.Client.hasCanvasImageData()) {
  31                         var data = Pixastic.prepareData(params);
  32
  33                         var rect = params.options.rect;
  34                         var w = rect.width;
  35                         var h = rect.height;
  36
  37                         var w4 = w*4;
  38                         var y = h;
  39
  40                         do {
  41                                 var offsetY = (y-1)*w4;
  42                                 var x = w;
  43                                 do {
  44                                         var offset = offsetY + (x*4-4);
  45
  46                                         var r = data[offset];
  47                                         var g = data[offset+1];
  48                                         var b = data[offset+2];
  49
  50                                         if (hue != 0 || saturation != 0) {
  51                                                 // ok, here comes rgb to hsl + adjust + hsl to rgb, all in one jumbled mess.
  52                                                 // It's not so pretty, but it's been optimized to get somewhat decent performance.
  53                                                 // The transforms were originally adapted from the ones found in Graphics Gems, but have been heavily modified.
  54                                                 var vs = r;
  55                                                 if (g > vs) vs = g;
  56                                                 if (b > vs) vs = b;
  57                                                 var ms = r;
  58                                                 if (g < ms) ms = g;
  59                                                 if (b < ms) ms = b;
  60                                                 var vm = (vs-ms);
  61                                                 var l = (ms+vs)/255 * 0.5;
  62                                                 if (l > 0) {
  63                                                         if (vm > 0) {
  64                                                                 if (l <= 0.5) {
  65                                                                         var s = vm / (vs+ms) * satMul;
  66                                                                         if (s > 1) s = 1;
  67                                                                         var v = (l * (1+s));
  68                                                                 } else {
  69                                                                         var s = vm / (510-vs-ms) * satMul;
  70                                                                         if (s > 1) s = 1;
  71                                                                         var v = (l+s - l*s);
  72                                                                 }
  73                                                                 if (r == vs) {
  74                                                                         if (g == ms)
  75                                                                                 var h = 5 + ((vs-b)/vm) + hue6;
  76                                                                         else
  77                                                                                 var h = 1 - ((vs-g)/vm) + hue6;
  78                                                                 } else if (g == vs) {
  79                                                                         if (b == ms)
  80                                                                                 var h = 1 + ((vs-r)/vm) + hue6;
  81                                                                         else
  82                                                                                 var h = 3 - ((vs-b)/vm) + hue6;
  83                                                                 } else {
  84                                                                         if (r == ms)
  85                                                                                 var h = 3 + ((vs-g)/vm) + hue6;
  86                                                                         else
  87                                                                                 var h = 5 - ((vs-r)/vm) + hue6;
  88                                                                 }
  89                                                                 if (h < 0) h+=6;
  90                                                                 if (h >= 6) h-=6;
  91                                                                 var m = (l+l-v);
  92                                                                 var sextant = h>>0;
  93                                                                 switch (sextant) {
  94                                                                         case 0: r = v*255; g = (m+((v-m)*(h-sextant)))*255; b = m*255; break;
  95                                                                         case 1: r = (v-((v-m)*(h-sextant)))*255; g = v*255; b = m*255; break;
  96                                                                         case 2: r = m*255; g = v*255; b = (m+((v-m)*(h-sextant)))*255; break;
  97                                                                         case 3: r = m*255; g = (v-((v-m)*(h-sextant)))*255; b = v*255; break;
  98                                                                         case 4: r = (m+((v-m)*(h-sextant)))*255; g = m*255; b = v*255; break;
  99                                                                         case 5: r = v*255; g = m*255; b = (v-((v-m)*(h-sextant)))*255; break;
 100                                                                 }
 101                                                         }
 102                                                 }
 103                                         }
 104
 105                                         if (lightness < 0) {
 106                                                 r *= lightp1;
 107                                                 g *= lightp1;
 108                                                 b *= lightp1;
 109                                         } else if (lightness > 0) {
 110                                                 r = r * lightm1 + light255;
 111                                                 g = g * lightm1 + light255;
 112                                                 b = b * lightm1 + light255;
 113                                         }
 114
 115                                         if (r < 0) r = 0;
 116                                         if (g < 0) g = 0;
 117                                         if (b < 0) b = 0;
 118                                         if (r > 255) r = 255;
 119                                         if (g > 255) g = 255;
 120                                         if (b > 255) b = 255;
 121
 122                                         data[offset] = r;
 123                                         data[offset+1] = g;
 124                                         data[offset+2] = b;
 125
 126                                 } while (--x);
 127                         } while (--y);
 128                         return true;
 129                 }
 130         },
 131         checkSupport : function() {
 132                 return Pixastic.Client.hasCanvasImageData();
 133         }
 134
 135 }