third_party/WebKit/LayoutTests/fast/canvas/script-tests/canvas-copyPixels.js

   1 description("Test if putImageData gives back the same result as getImageData");
   2 var ctx = document.createElement('canvas').getContext('2d');
   3
   4 ctx.fillStyle = "red";
   5 ctx.fillRect(0,0,50,20);
   6 ctx.fillStyle = "green";
   7 ctx.fillRect(50,0,50,20);
   8 ctx.fillStyle = "blue";
   9 ctx.fillRect(100,0,50,20);
  10
  11 var data = ctx.getImageData(0,0,150,20);
  12 ctx.putImageData(data, 0, 20);
  13
  14 var imageData = ctx.getImageData(1, 21, 48, 18);
  15 var imgdata = imageData.data;
  16 shouldBe("imgdata[4]", "255");
  17 shouldBe("imgdata[5]", "0");
  18 shouldBe("imgdata[6]", "0");
  19
  20 imageData = ctx.getImageData(51, 21, 48, 18);
  21 imgdata = imageData.data;
  22 shouldBe("imgdata[4]", "0");
  23 shouldBe("imgdata[5]", "128");
  24 shouldBe("imgdata[6]", "0");
  25
  26 imageData = ctx.getImageData(101, 21, 48, 18);
  27 imgdata = imageData.data;
  28 shouldBe("imgdata[4]", "0");
  29 shouldBe("imgdata[5]", "0");
  30 shouldBe("imgdata[6]", "255");