Added the CanvasImageSource interface, which all types that a canvas can draw

tests/html/canvasrenderingcontext2d_test.dart

 // Copyright (c) 2012, 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.
 
-library url_test;
+library canvas_rendering_context_2d_test;
 import '../../pkg/unittest/lib/unittest.dart';
 import '../../pkg/unittest/lib/html_config.dart';
 import 'dart:html';
 import 'dart:math';
 
 // Some rounding errors in the browsers.
 checkPixel(List<int> pixel, List<int> expected) {
   expect(pixel[0], closeTo(expected[0], 2));
   expect(pixel[1], closeTo(expected[1], 2));
   expect(pixel[2], closeTo(expected[2], 2));
   expect(pixel[3], closeTo(expected[3], 2));
 }
 
 main() {
   useHtmlConfiguration();
 
   group('canvasRenderingContext2d', () {
     var canvas;
     var context;
+    var otherCanvas;
+    var otherContext;
+
+    void createOtherCanvas() {
+      otherCanvas = new CanvasElement();
+      otherCanvas.width = 10;
+      otherCanvas.height = 10;
+      otherContext = otherCanvas.context2d;
+      otherContext.fillStyle = "red";
+      otherContext.fillRect(0, 0, otherCanvas.width, otherCanvas.height);
+    }
 
     setUp(() {
       canvas = new CanvasElement();
       canvas.width = 100;
       canvas.height = 100;
 
       context = canvas.context2d;
+
+      createOtherCanvas();
     });
 
     tearDown(() {
       canvas = null;
       context = null;
+      otherCanvas = null;
+      otherContext = null;
     });
 
     List<int> readPixel(int x, int y) {
       var imageData = context.getImageData(x, y, 1, 1);
       return imageData.data;
     }
 
     /// Returns true if the pixel has some data in it, false otherwise.
     bool isPixelFilled(int x, int y) => readPixel(x,y).any((p) => p != 0);
 
@@ skipping 183 matching lines @@
 
       // (cx - r/SQRT2, cy - r/SQRT2) should be filled.
       expectPixelFilled((cx - r/SQRT2).toInt(), (cy + r/SQRT2).toInt(), true);
 
       // (cx + r/SQRT2, cy + r/SQRT2) should be filled.
       expectPixelFilled((cx - r/SQRT2).toInt(), (cy - r/SQRT2).toInt(), true);
 
       // (cx - r/SQRT2, cy - r/SQRT2) should be filled.
       expectPixelFilled((cx + r/SQRT2).toInt(), (cy - r/SQRT2).toInt(), true);
     });
+
+    // Draw an image to the canvas from an image element.
+    test('drawImage from img element with 3 params', () {
+      var dataUrl = otherCanvas.toDataUrl('image/gif');
+      var img = new ImageElement();
+
+      img.onLoad.listen(expectAsync1((_) {
+        context.drawImage(img, 50, 50);
+
+        expectPixelFilled(50, 50);
+        expectPixelFilled(55, 55);
+        expectPixelFilled(59, 59);
+        expectPixelUnfilled(60, 60);
+        expectPixelUnfilled(0, 0);
+        expectPixelUnfilled(70, 70);
+      }));
+      img.onError.listen((_) {
+        guardAsync(() {
+          fail('URL failed to load.');
+        });
+      });
+      img.src = dataUrl;
+    });
+
+    // Draw an image to the canvas from an image element and scale it.
+    test('drawImage from img element with 5 params', () {
+      var dataUrl = otherCanvas.toDataUrl('image/gif');
+      var img = new ImageElement();
+
+      img.onLoad.listen(expectAsync1((_) {
+        context.drawImageAtScale(img, new Rect(50, 50, 20, 20));
+
+        expectPixelFilled(50, 50);
+        expectPixelFilled(55, 55);
+        expectPixelFilled(59, 59);
+        expectPixelFilled(60, 60);
+        expectPixelFilled(69, 69);
+        expectPixelUnfilled(70, 70);
+        expectPixelUnfilled(0, 0);
+        expectPixelUnfilled(80, 80);
+      }));
+      img.onError.listen((_) {
+        guardAsync(() {
+          fail('URL failed to load.');
+        });
+      });
+      img.src = dataUrl;
+    });
+
+    // Draw an image to the canvas from an image element and scale it.
+    test('drawImage from img element with 9 params', () {
+      otherContext.fillStyle = "blue";
+      otherContext.fillRect(5, 5, 5, 5);
+      var dataUrl = otherCanvas.toDataUrl('image/gif');
+      var img = new ImageElement();
+
+      img.onLoad.listen(expectAsync1((_) {
+        // This will take a 6x6 square from the first canvas from position 2,2
+        // and then scale it to a 20x20 square and place it to the second canvas
+        // at 50,50.
+        context.drawImageAtScale(img, new Rect(50, 50, 20, 20),
+          sourceRect: new Rect(2, 2, 6, 6));
+
+        checkPixel(readPixel(50, 50), [255, 0, 0, 255]);
+        checkPixel(readPixel(55, 55), [255, 0, 0, 255]);
+        checkPixel(readPixel(60, 50), [255, 0, 0, 255]);
+        checkPixel(readPixel(65, 65), [0, 0, 255, 255]);
+        checkPixel(readPixel(69, 69), [0, 0, 255, 255]);
+
+        expectPixelFilled(50, 50);
+        expectPixelFilled(55, 55);
+        expectPixelFilled(59, 59);
+        expectPixelFilled(60, 60);
+        expectPixelFilled(69, 69);
+        expectPixelUnfilled(70, 70);
+        expectPixelUnfilled(0, 0);
+        expectPixelUnfilled(80, 80);
+      }));
+      img.onError.listen((_) {
+        guardAsync(() {
+          fail('URL failed to load.');
+        });
+      });
+      img.src = dataUrl;
+    });
+
+    // These base64 strings are the same video, representing 2 frames of 8x8 red
+    // pixels.
+    // The videos were created with:
+    //   convert -size 8x8 xc:red blank1.jpg
+    //   convert -size 8x8 xc:red blank2.jpg
+    //   avconv -f image2  -i "blank%d.jpg" -c:v libx264 small.mp4
+    //   python -m base64 -e small.mp4
+    //   avconv -i small.mp4 small.webm
+    //   python -m base64 -e small.webm
+    var mp4VideoUrl =
+      'data:video/mp4;base64,AAAAIGZ0eXBpc29tAAACAGlzb21pc28yYXZjMW1wNDEAAAAIZn'
+      'JlZQAAAsdtZGF0AAACmwYF//+X3EXpvebZSLeWLNgg2SPu73gyNjQgLSBjb3JlIDEyMCByMj'
+      'E1MSBhM2Y0NDA3IC0gSC4yNjQvTVBFRy00IEFWQyBjb2RlYyAtIENvcHlsZWZ0IDIwMDMtMj'
+      'AxMSAtIGh0dHA6Ly93d3cudmlkZW9sYW4ub3JnL3gyNjQuaHRtbCAtIG9wdGlvbnM6IGNhYm'
+      'FjPTEgcmVmPTMgZGVibG9jaz0xOjA6MCBhbmFseXNlPTB4MToweDExMSBtZT1oZXggc3VibW'
+      'U9NyBwc3k9MSBwc3lfcmQ9MS4wMDowLjAwIG1peGVkX3JlZj0wIG1lX3JhbmdlPTE2IGNocm'
+      '9tYV9tZT0xIHRyZWxsaXM9MSA4eDhkY3Q9MCBjcW09MCBkZWFkem9uZT0yMSwxMSBmYXN0X3'
+      'Bza2lwPTEgY2hyb21hX3FwX29mZnNldD0tMiB0aHJlYWRzPTE4IHNsaWNlZF90aHJlYWRzPT'
+      'AgbnI9MCBkZWNpbWF0ZT0xIGludGVybGFjZWQ9MCBibHVyYXlfY29tcGF0PTAgY29uc3RyYW'
+      'luZWRfaW50cmE9MCBiZnJhbWVzPTMgYl9weXJhbWlkPTAgYl9hZGFwdD0xIGJfYmlhcz0wIG'
+      'RpcmVjdD0xIHdlaWdodGI9MCBvcGVuX2dvcD0xIHdlaWdodHA9MiBrZXlpbnQ9MjUwIGtleW'
+      'ludF9taW49MjUgc2NlbmVjdXQ9NDAgaW50cmFfcmVmcmVzaD0wIHJjX2xvb2thaGVhZD00MC'
+      'ByYz1jcmYgbWJ0cmVlPTEgY3JmPTUxLjAgcWNvbXA9MC42MCBxcG1pbj0wIHFwbWF4PTY5IH'
+      'Fwc3RlcD00IGlwX3JhdGlvPTEuMjUgYXE9MToxLjAwAIAAAAARZYiEB//3aoK5/tP9+8yeuI'
+      'EAAAAHQZoi2P/wgAAAAzxtb292AAAAbG12aGQAAAAAAAAAAAAAAAAAAAPoAAAAUAABAAABAA'
+      'AAAAAAAAAAAAAAAQAAAAAAAAAAAAAAAAAAAAEAAAAAAAAAAAAAAAAAAEAAAAAAAAAAAAAAAA'
+      'AAAAAAAAAAAAAAAAAAAAAAAAACAAAAGGlvZHMAAAAAEICAgAcAT/////7/AAACUHRyYWsAAA'
+      'BcdGtoZAAAAA8AAAAAAAAAAAAAAAEAAAAAAAAAUAAAAAAAAAAAAAAAAAAAAAAAAQAAAAAAAA'
+      'AAAAAAAAAAAAEAAAAAAAAAAAAAAAAAAEAAAAAACAAAAAgAAAAAACRlZHRzAAAAHGVsc3QAAA'
+      'AAAAAAAQAAAFAAAAABAAEAAAAAAchtZGlhAAAAIG1kaGQAAAAAAAAAAAAAAAAAAAAZAAAAAl'
+      'XEAAAAAAAtaGRscgAAAAAAAAAAdmlkZQAAAAAAAAAAAAAAAFZpZGVvSGFuZGxlcgAAAAFzbW'
+      'luZgAAABR2bWhkAAAAAQAAAAAAAAAAAAAAJGRpbmYAAAAcZHJlZgAAAAAAAAABAAAADHVybC'
+      'AAAAABAAABM3N0YmwAAACXc3RzZAAAAAAAAAABAAAAh2F2YzEAAAAAAAAAAQAAAAAAAAAAAA'
+      'AAAAAAAAAACAAIAEgAAABIAAAAAAAAAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA'
+      'AAAAAY//8AAAAxYXZjQwFNQAr/4QAYZ01ACuiPyy4C2QAAAwABAAADADIPEiUSAQAGaOvAZS'
+      'yAAAAAGHN0dHMAAAAAAAAAAQAAAAIAAAABAAAAFHN0c3MAAAAAAAAAAQAAAAEAAAAYY3R0cw'
+      'AAAAAAAAABAAAAAgAAAAEAAAAcc3RzYwAAAAAAAAABAAAAAQAAAAEAAAABAAAAHHN0c3oAAA'
+      'AAAAAAAAAAAAIAAAK0AAAACwAAABhzdGNvAAAAAAAAAAIAAAAwAAAC5AAAAGB1ZHRhAAAAWG'
+      '1ldGEAAAAAAAAAIWhkbHIAAAAAAAAAAG1kaXJhcHBsAAAAAAAAAAAAAAAAK2lsc3QAAAAjqX'
+      'RvbwAAABtkYXRhAAAAAQAAAABMYXZmNTMuMjEuMQ==';
+    var webmVideoUrl =
+      'data:video/webm;base64,GkXfowEAAAAAAAAfQoaBAUL3gQFC8oEEQvOBCEKChHdlYm1Ch'
+      '4ECQoWBAhhTgGcBAAAAAAAB/hFNm3RALE27i1OrhBVJqWZTrIHfTbuMU6uEFlSua1OsggEsT'
+      'buMU6uEHFO7a1OsggHk7AEAAAAAAACkAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA'
+      'AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA'
+      'AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA'
+      'AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAVSalmAQAAAAAAAEEq17GDD0JATYCLTGF2ZjUzL'
+      'jIxLjFXQYtMYXZmNTMuMjEuMXOkkJatuHwTJ7cvFLSzBSmxbp5EiYhAVAAAAAAAABZUrmsBA'
+      'AAAAAAAR64BAAAAAAAAPteBAXPFgQGcgQAitZyDdW5khoVWX1ZQOIOBASPjg4QCYloA4AEAA'
+      'AAAAAASsIEIuoEIVLCBCFS6gQhUsoEDH0O2dQEAAAAAAABZ54EAo72BAACA8AIAnQEqCAAIA'
+      'ABHCIWFiIWEiAICAnWqA/gD+gINTRgA/v0hRf/kb+PnRv/I4//8WE8DijI//FRAo5WBACgAs'
+      'QEAARAQABgAGFgv9AAIAAAcU7trAQAAAAAAAA67jLOBALeH94EB8YIBfw==';
+
+    test('drawImage from video element with 3 params', () {
+      var video = new VideoElement();
+
+      video.onLoadedData.listen(expectAsync1((_) {
+        context.drawImage(video, 50, 50);
+
+        expectPixelFilled(50, 50);
+        expectPixelFilled(54, 54);
+        expectPixelFilled(57, 57);
+        expectPixelUnfilled(58, 58);
+        expectPixelUnfilled(0, 0);
+        expectPixelUnfilled(70, 70);
+      }));
+      video.onError.listen((_) {
+        guardAsync(() {
+          fail('URL failed to load.');
+        });
+      });
+
+      if(video.canPlayType('video/webm; codecs="vp8.0, vorbis"', '') != '') {
+        video.src = webmVideoUrl;
+      } else if(video.canPlayType('video/mp4; codecs="avc1.4D401E, mp4a.40.2"',
+            null) != '') {
+        video.src = mp4VideoUrl;
+      } else {
+        logMessage('Video is not supported on this system.');
+      }
+    });
+
+    test('drawImage from video element with 5 params', () {
+      var video = new VideoElement();
+
+      video.onLoadedData.listen(expectAsync1((_) {
+        context.drawImageAtScale(video, new Rect(50, 50, 20, 20));
+
+        expectPixelFilled(50, 50);
+        expectPixelFilled(55, 55);
+        expectPixelFilled(59, 59);
+        expectPixelFilled(60, 60);
+        expectPixelFilled(69, 69);
+        expectPixelUnfilled(70, 70);
+        expectPixelUnfilled(0, 0);
+        expectPixelUnfilled(80, 80);
+      }));
+      video.onError.listen((_) {
+        guardAsync(() {
+          fail('URL failed to load.');
+        });
+      });
+
+      if(video.canPlayType('video/webm; codecs="vp8.0, vorbis"', '') != '') {
+        video.src = webmVideoUrl;
+      } else if(video.canPlayType('video/mp4; codecs="avc1.4D401E, mp4a.40.2"',
+            null) != '') {
+        video.src = mp4VideoUrl;
+      } else {
+        // TODO(amouravski): Better fallback?
+        logMessage('Video is not supported on this system.');
+      }
+    });
+
+    test('drawImage from video element with 9 params', () {
+      var video = new VideoElement();
+
+      video.onLoadedData.listen(expectAsync1((_) {
+        context.drawImageAtScale(video, new Rect(50, 50, 20, 20),
+          sourceRect: new Rect(2, 2, 6, 6));
+
+        expectPixelFilled(50, 50);
+        expectPixelFilled(55, 55);
+        expectPixelFilled(59, 59);
+        expectPixelFilled(60, 60);
+        expectPixelFilled(69, 69);
+        expectPixelUnfilled(70, 70);
+        expectPixelUnfilled(0, 0);
+        expectPixelUnfilled(80, 80);
+      }));
+      video.onError.listen((_) {
+        guardAsync(() {
+          fail('URL failed to load.');
+        });
+      });
+
+      if(video.canPlayType('video/webm; codecs="vp8.0, vorbis"', '') != '') {
+        video.src = webmVideoUrl;
+      } else if(video.canPlayType('video/mp4; codecs="avc1.4D401E, mp4a.40.2"',
+            null) != '') {
+        video.src = mp4VideoUrl;
+      } else {
+        // TODO(amouravski): Better fallback?
+        logMessage('Video is not supported on this system.');
+      }
+    });
+
+    test('drawImage from canvas element with 3 params', () {
+      // Draw an image to the canvas from a canvas element.
+      context.drawImage(otherCanvas, 50, 50);
+
+      expectPixelFilled(50, 50);
+      expectPixelFilled(55, 55);
+      expectPixelFilled(59, 59);
+      expectPixelUnfilled(60, 60);
+      expectPixelUnfilled(0, 0);
+      expectPixelUnfilled(70, 70);
+    });
+    test('drawImage from canvas element with 5 params', () {
+      // Draw an image to the canvas from a canvas element.
+      context.drawImageAtScale(otherCanvas, new Rect(50, 50, 20, 20));
+
+      expectPixelFilled(50, 50);
+      expectPixelFilled(55, 55);
+      expectPixelFilled(59, 59);
+      expectPixelFilled(60, 60);
+      expectPixelFilled(69, 69);
+      expectPixelUnfilled(70, 70);
+      expectPixelUnfilled(0, 0);
+      expectPixelUnfilled(80, 80);
+    });
+    test('drawImage from canvas element with 9 params', () {
+      // Draw an image to the canvas from a canvas element.
+      otherContext.fillStyle = "blue";
+      otherContext.fillRect(5, 5, 5, 5);
+      context.drawImageAtScale(otherCanvas, new Rect(50, 50, 20, 20),
+          sourceRect: new Rect(2, 2, 6, 6));
+
+      checkPixel(readPixel(50, 50), [255, 0, 0, 255]);
+      checkPixel(readPixel(55, 55), [255, 0, 0, 255]);
+      checkPixel(readPixel(60, 50), [255, 0, 0, 255]);
+      checkPixel(readPixel(65, 65), [0, 0, 255, 255]);
+      checkPixel(readPixel(69, 69), [0, 0, 255, 255]);
+      expectPixelFilled(50, 50);
+      expectPixelFilled(55, 55);
+      expectPixelFilled(59, 59);
+      expectPixelFilled(60, 60);
+      expectPixelFilled(69, 69);
+      expectPixelUnfilled(70, 70);
+      expectPixelUnfilled(0, 0);
+      expectPixelUnfilled(80, 80);
+    });
   });
 }