| <!DOCTYPE HTML> |
| <html> |
| <head> |
| <script src="../../resources/testharness.js"></script> |
| <script src="../../resources/testharnessreport.js"></script> |
| <style> |
| |
| #canvas3 { |
| width : 100px; |
| height : 100px; |
| border : 1px solid green; |
| } |
| |
| </style> |
| <canvas id="canvas1" width="8" height="8"></canvas> |
| <canvas id="canvas2" width="8" height="8"></canvas> |
| <canvas id="canvas3" width="8" height="8"></canvas> |
| <canvas id="canvas4" width="8" height="8"></canvas> |
| </head> |
| <body> |
| <script> |
| test(function(t) { |
| var canvas1 = document.getElementById('canvas1'); |
| var canvas2 = document.getElementById('canvas2'); |
| var canvas3 = document.getElementById('canvas3'); |
| var canvas4 = document.getElementById('canvas4'); |
| |
| var ctx1 = canvas1.getContext('2d'); |
| var ctx2 = canvas2.getContext('2d', {} ); |
| var ctx3 = canvas3.getContext('2d', { alpha: false } ); |
| var ctx4 = canvas4.getContext('2d', { alpha: true } ); |
| |
| assert_equals(ctx1.getContextAttributes().alpha,true); |
| var imgData1 = ctx1.getImageData(0, 0, 1, 1); |
| assert_equals(imgData1.data[0],0); |
| assert_equals(imgData1.data[1],0); |
| assert_equals(imgData1.data[2],0); |
| assert_equals(imgData1.data[3],0); |
| |
| assert_equals(ctx2.getContextAttributes().alpha,true); |
| var imgData2 = ctx2.getImageData(0, 0, 1, 1); |
| assert_equals(imgData2.data[0],0); |
| assert_equals(imgData2.data[1],0); |
| assert_equals(imgData2.data[2],0); |
| assert_equals(imgData2.data[3],0); |
| |
| assert_equals(ctx3.getContextAttributes().alpha,false); |
| assert_equals(ctx4.getContextAttributes().alpha,true); |
| |
| var imgData4 = ctx4.getImageData(0, 0, 1, 1); |
| assert_equals(imgData4.data[0],0); |
| assert_equals(imgData4.data[1],0); |
| assert_equals(imgData4.data[2],0); |
| assert_equals(imgData4.data[3],0); |
| |
| // Check that mutating the returned value of getContextAttributes() doesn't |
| // affect the existing canvas, or the values of subsequent calls to |
| // getContextAttributes(). |
| var attrs = ctx4.getContextAttributes(); |
| assert_equals(attrs.alpha,true); |
| attrs.alpha = false; |
| |
| var imgData4 = ctx4.getImageData(0, 0, 1, 1); |
| assert_equals(ctx4.getContextAttributes().alpha,true); |
| assert_equals(imgData4.data[0],0); |
| assert_equals(imgData4.data[1],0); |
| assert_equals(imgData4.data[2],0); |
| assert_equals(imgData4.data[3],0); |
| }, 'Series of tests for canvas alpha'); |
| </script> |
| </body> |
| </html> |
