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<!DOCTYPE html>
<html>
<meta charset="utf-8">
<title>Reference for Bug 1972885</title>
<style>
body {
margin: 0;
}
canvas {
/* Rounded up. */
margin-top: 2px;
width: 100px;
/* Subpixel snapped down. */
height: 100px;
}
</style>
<canvas id="canvas"></canvas>
<script>
function draw(canvas, width, height) {
const ctx = canvas.getContext('2d');
canvas.width = width;
canvas.height = height;
const imgData = ctx.createImageData(width, height);
const u32View = new Uint32Array(imgData.data.buffer);
u32View.fill(0xFFFFFFFF);
for (let y = 0; y < height; y += 2) {
for (let x = 0; x < width; x++) {
u32View[y * width + x] = 0xFF000000;
}
}
ctx.putImageData(imgData, 0, 0);
}
draw(canvas, 100, 100);
</script>
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