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Isolated test case for canvas negative scaling of images, aiming to pin the issue to excanvas in IE8.
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| <!DOCTYPE html> | |
| <html> | |
| <head> | |
| <title>Canvas - Image Negative Scaling</title> | |
| <!--[if IE]> | |
| <script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/flot/0.8.3/excanvas.min.js"></script> | |
| <![endif]--> | |
| </head> | |
| <body> | |
| <button id="action">Negative Scaling</button> | |
| <canvas id="canvas" width="400" height="300"></canvas> | |
| <script type="text/javascript"> | |
| (function($window) { | |
| $window.onload = function() { | |
| var ctx = canvas.getContext('2d'), | |
| imageUrl = 'http://fabricjs.com/assets/pug.jpg', | |
| image = new Image(), | |
| button = document.getElementById('action'), | |
| flipped = false; | |
| image.onload = function() { | |
| ctx.drawImage(this, 200, 0, 180, 300); | |
| } | |
| image.src = imageUrl; | |
| button.onclick = function() { | |
| flipped = !flipped; | |
| ctx.clearRect(0,0,400,300); | |
| ctx.save(); | |
| ctx.scale(flipped? -1 : 1,1); | |
| ctx.drawImage(image, flipped? -200 : 200, 0, 180, 300); | |
| ctx.restore(); | |
| }; | |
| } | |
| })(window); | |
| </script> | |
| </body> | |
| </html> |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| <!DOCTYPE html> | |
| <html> | |
| <head> | |
| <title>Canvas - Image Negative Scaling</title> | |
| <!--[if IE]> | |
| <script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/flot/0.8.3/excanvas.min.js"></script> | |
| <![endif]--> | |
| </head> | |
| <body> | |
| <button id="action">Rotate</button> | |
| <canvas id="canvas" width="400" height="400"></canvas> | |
| <script type="text/javascript"> | |
| (function($window) { | |
| $window.onload = function() { | |
| var ctx = canvas.getContext('2d'), | |
| imageUrl = 'http://fabricjs.com/assets/pug.jpg', | |
| image = new Image(), | |
| button = document.getElementById('action'), | |
| flipped = false; | |
| image.onload = function() { | |
| ctx.drawImage(this, 50, 100, 300, 200); | |
| } | |
| image.src = imageUrl; | |
| button.onclick = function() { | |
| flipped = !flipped; | |
| ctx.clearRect(0,0,400,400); | |
| ctx.save(); | |
| ctx.translate(200,200); | |
| ctx.rotate(flipped? Math.PI/4 : 0); | |
| ctx.translate(-150,-100); | |
| ctx.drawImage(image, 0, 0, 300, 200); | |
| ctx.restore(); | |
| }; | |
| } | |
| })(window); | |
| </script> | |
| </body> | |
| </html> |
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