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Test Info:
- This WPT test may be referenced by the following Test IDs:
- /html/canvas/offscreen/layers/2d.layer.non-invertible-matrix.with-render-states-and-filter.w.html - WPT Dashboard Interop Dashboard
<!DOCTYPE html>
<!-- DO NOT EDIT! This test has been generated by /html/canvas/tools/gentest.py. -->
<meta charset="UTF-8">
<html class="reftest-wait">
<link rel="match" href="2d.layer.non-invertible-matrix.with-render-states-and-filter-expected.html">
<title>Canvas test: 2d.layer.non-invertible-matrix.with-render-states-and-filter</title>
<h1>2d.layer.non-invertible-matrix.with-render-states-and-filter</h1>
<p class="desc">Test drawing layers when the transform is not invertible.</p>
<canvas id="canvas" width="200" height="200">
<p class="fallback">FAIL (fallback content)</p>
</canvas>
<script id='myWorker' type='text/worker'>
self.onmessage = function(e) {
const canvas = new OffscreenCanvas(200, 200);
const ctx = canvas.getContext('2d');
ctx.fillStyle = 'blue';
ctx.fillRect(30, 30, 50, 50);
// Anything below will be non-rasterizable.
ctx.scale(1, 0);
ctx.globalAlpha = 0.8;
ctx.globalCompositeOperation = 'multiply';
ctx.shadowOffsetX = 0;
ctx.shadowOffsetY = 20;
ctx.shadowColor = 'rgba(255, 165, 0, 0.6)';
// Open the layer with a non-invertible matrix. The whole layer will be
// non-rasterizable.
ctx.beginLayer({filter:
{name: 'dropShadow', dx: 10, dy: 0, stdDeviation: 0,
floodColor: 'rgba(128, 128, 255, 0.7)'}});
// Because the transform is global, the matrix is still non-invertible.
ctx.fillStyle = 'rgba(225, 0, 0, 1)';
ctx.fillRect(40, 70, 50, 50);
// Set a valid matrix in the middle of the layer. This makes the global
// matrix invertible again, but because because the layer was opened with a
// non-invertible matrix, the whole layer remains non-rasterizable.
ctx.setTransform(1, 0, 0, 1, 0, 0);
ctx.fillStyle = 'green';
ctx.fillRect(70, 40, 50, 50);
ctx.endLayer();
const bitmap = canvas.transferToImageBitmap();
self.postMessage(bitmap, bitmap);
};
</script>
<script>
const blob = new Blob([document.getElementById('myWorker').textContent]);
const worker = new Worker(URL.createObjectURL(blob));
worker.addEventListener('message', msg => {
const outputCtx = document.getElementById("canvas").getContext('2d');
outputCtx.drawImage(msg.data, 0, 0);
document.documentElement.classList.remove("reftest-wait");
});
worker.postMessage(null);
</script>
</html>