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

   1 /*
   2  * Pixastic Lib - Mosaic filter - 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.mosaic = {
   8
   9         process : function(params) {
  10                 var blockSize = Math.max(1,parseInt(params.options.blockSize,10));
  11
  12                 if (Pixastic.Client.hasCanvasImageData()) {
  13                         var rect = params.options.rect;
  14                         var w = rect.width;
  15                         var h = rect.height;
  16                         var w4 = w*4;
  17                         var y = h;
  18
  19                         var ctx = params.canvas.getContext("2d");
  20
  21                         var pixel = document.createElement("canvas");
  22                         pixel.width = pixel.height = 1;
  23                         var pixelCtx = pixel.getContext("2d");
  24
  25                         var copy = document.createElement("canvas");
  26                         copy.width = w;
  27                         copy.height = h;
  28                         var copyCtx = copy.getContext("2d");
  29                         copyCtx.drawImage(params.canvas,rect.left,rect.top,w,h, 0,0,w,h);
  30
  31                         for (var y=0;y<h;y+=blockSize) {
  32                                 for (var x=0;x<w;x+=blockSize) {
  33                                         pixelCtx.drawImage(copy, x, y, blockSize, blockSize, 0, 0, 1, 1);
  34                                         var data = pixelCtx.getImageData(0,0,1,1).data;
  35                                         ctx.fillStyle = "rgb(" + data[0] + "," + data[1] + "," + data[2] + ")";
  36                                         ctx.fillRect(rect.left + x, rect.top + y, blockSize, blockSize);
  37                                 }
  38                         }
  39
  40                         params.useData = false;
  41
  42                         return true;
  43                 }
  44         },
  45         checkSupport : function() {
  46                 return (Pixastic.Client.hasCanvasImageData());
  47         }
  48 }