LayoutTests/fast/canvas/drawImage-with-negative-source-destination_t01.dart

/*
 * Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 * for details. All rights reserved. Use of this source code is governed by a
 * BSD-style license that can be found in the LICENSE file.
 */
/** 
 * @description Series of tests to ensure correct behaviour on negative
 * source/destination of a HTMLCanvasElement
 */
import "dart:html";
import "dart:math" as Math;
import "../../testcommon.dart";
import "../../../Utils/async_utils.dart";

main() {
  document.body.setInnerHtml('''
      <!-- Test based on that found at 
           http://philip.html5.org/tests/canvas/suite/tests/2d.drawImage.negativesource.html
        -->
      <canvas id="canvas" width="100" height="100"></canvas>
      <div>PASS</div>
      ''', treeSanitizer: new NullTreeSanitizer());

  var canvas2 = document.createElement('canvas');
  canvas2.width = 100;
  canvas2.height = 100;
  var ctx2 = canvas2.getContext('2d');
  ctx2.fillStyle = '#f00';
  ctx2.fillRect(0, 0, 100, 50);
  ctx2.fillStyle = '#0f0';
  ctx2.fillRect(0, 50, 100, 50);

  var canvas = getContext2d("canvas");
  canvas.drawImageScaledFromSource(canvas2, 100, 50, -50, 50, 0, 0, 50, 50);
  canvas.drawImageScaledFromSource(canvas2, 100, 100, -50, -50, 0, 100, 50, -50);
  canvas.drawImageScaledFromSource(canvas2, 0, 100, 100, -50, 100, 100, -50, -50);
  canvas.drawImageScaledFromSource(canvas2, 0, 50, 100, 50, 100, 0, -50, 50);

  var imageData = canvas.getImageData(0, 0, 100, 100);
  var imgdata = imageData.data;
  shouldBe(imgdata[4], 0);
  shouldBe(imgdata[5], 255);
  shouldBe(imgdata[6], 0);

  // test width or height -1
  canvas.fillStyle = '#000';
  canvas.fillRect(0, 0, 1, 2);
  canvas.drawImageScaledFromSource(canvas2, 0, 0, 1, 1, 1, 1, -1, -1);
  imageData = canvas.getImageData(0, 0, 1, 2);
  imgdata = imageData.data;
  shouldBe(imgdata[0], 255);
  shouldBe(imgdata[1], 0);
  shouldBe(imgdata[2], 0);
  shouldBe(imgdata[4], 0);
  shouldBe(imgdata[5], 0);
  shouldBe(imgdata[6], 0);
}