gecko-dev/layout/reftests/canvas/672646-alpha-radial-gradient.html
Jeff Muizelaar e4aa8bf5dd Bug 672646. D2D: Fix trasparent radial gradients. r=roc
The output merger stage was expecting premultiplied alpha
and we were giving non-premultiplied. Fix by premultiplying
in the shader.

Also adds a reftest for this situation.
2011-07-21 18:40:41 -04:00

25 lines
596 B
HTML

<!doctype html>
<head>
<style>
body {
background-color: blue;
}
</style>
<body>
<canvas id="mycanvas" width="200" height="200"></canvas>
<script type="text/javascript">
var cx = document.getElementById('mycanvas').getContext('2d');
var g = cx.createRadialGradient(100, 100, 50, 100, 100, 75);
g.addColorStop(0, 'rgba(100%, 100%, 0%, 0.5)');
g.addColorStop(1, 'rgba(100%, 100%, 0%, 0)');
cx.fillStyle = g;
cx.fillRect(0, 0, 200, 200);
cx.beginPath();
cx.arc(100, 100, 80, 0, Math.PI*2, true);
cx.closePath();
cx.fillStyle = "white";
cx.fill();
</script>