/*
   * Pixastic Lib - Lighten filter - v0.1.0
   * Copyright (c) 2008 Jacob Seidelin, jseidelin@nihilogic.dk, http://blog.nihilogic.dk/
   * MIT License [http://www.opensource.org/licenses/mit-license.php]
   */
  
  Pixastic.Actions.lighten = {
  
          process : function(params) {
                  var amount = parseFloat(params.options.amount) || 0;
  
                  if (Pixastic.Client.hasCanvasImageData()) {
                          var data = Pixastic.prepareData(params);
                          var rect = params.options.rect;
                          var w = rect.width;
                          var h = rect.height;
                          var w4 = w*4;
                          var y = h;
                          do {
                                  var offsetY = (y-1)*w4;
                                  var x = w;
                                  do {
                                          var offset = offsetY + (x-1)*4;
  
                                          var r = data[offset];
                                          var g = data[offset+1];
                                          var b = data[offset+2];
  
                                          r += r*amount;
                                          g += g*amount;
                                          b += b*amount;
  
                                          if (r < 0 ) r = 0;
                                          if (g < 0 ) g = 0;
                                          if (b < 0 ) b = 0;
                                          if (r > 255 ) r = 255;
                                          if (g > 255 ) g = 255;
                                          if (b > 255 ) b = 255;
  
                                          data[offset] = r;
                                          data[offset+1] = g;
                                          data[offset+2] = b;
  
                                  } while (--x);
                          } while (--y);
                          return true;
  
                  } else if (Pixastic.Client.isIE()) {
                          var img = params.image;
                          if (amount < 0) {
                                  img.style.filter += " light()";
                                  img.filters[img.filters.length-1].addAmbient(
                                          255,255,255,
                                          100 * -amount
                                  );
                          } else if (amount > 0) {
                                  img.style.filter += " light()";
                                  img.filters[img.filters.length-1].addAmbient(
                                          255,255,255,
                                          100
                                  );
                                  img.filters[img.filters.length-1].addAmbient(
                                          255,255,255,
                                          100 * amount
                                  );
                          }
                          return true;
                  }
          },
          checkSupport : function() {
                  return (Pixastic.Client.hasCanvasImageData() || Pixastic.Client.isIE());
          }
  }