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<!doctype HTML>
<html>
<head>
<title>HTML5 Canvas Test: globalCompositeOperation "destination-over"</title>
<link rel="match" href="canvas_compositing_globalcompositeoperation_001-ref.htm">
<link rel="author" title="Microsoft" href="http://www.microsoft.com" />
<link rel="help" href="http://www.w3.org/TR/2dcontext/#dom-context-2d-globalcompositeoperation" />
<meta name="assert" content="If the globalCompositeOperation is set to 'destination-over', display the destination image wherever the destination image is opaque." />
<script type="text/javascript">
function runTest()
{
var canvas = document.getElementById("canvas1");
var ctx = canvas.getContext("2d");
// Source image.
ctx.fillStyle = "rgba(0, 0, 0, 1.0)";
ctx.fillRect(0, 0, 100, 50);
// Assign the globalCompositeOperation.
ctx.globalCompositeOperation = "destination-over";
// Destination image.
ctx.fillStyle = "rgba(255, 0, 0, 1.0)";
ctx.fillRect(0, 0, 100, 50);
}
</script>
</head>
<body onload="runTest()">
<p>Description: If the globalCompositeOperation is set to "destination-over", display the destination image wherever the destination image is opaque.</p>
<canvas id="canvas1" width="300" height="150">Browser does not support HTML5 Canvas.</canvas>
</body>
</html>
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