OffscreenCanvas-Bitmaprenderer-resize.html

<!DOCTYPE html>
<html>
<body>
<canvas id="output" width="300" height="300"></canvas>
<script>
if (window.testRunner) {
    testRunner.waitUntilDone();
}
const canvas = document.getElementById('output');
const canvas1 = canvas.transferControlToOffscreen();
const context1 = canvas1.getContext('bitmaprenderer');
const canvas2 = new OffscreenCanvas(300, 300);
const context2 = canvas2.getContext('2d');

context2.fillStyle = 'blue';
context2.fillRect(0, 0, canvas2.width, canvas2.height);
context1.transferFromImageBitmap(canvas2.transferToImageBitmap());

requestAnimationFrame(function () {
    canvas1.width = canvas2.width = 350;
    context2.fillStyle = 'green';
    context2.fillRect(0, 0, canvas2.width, canvas2.height);
    context1.transferFromImageBitmap(canvas2.transferToImageBitmap());

    function waitForCanvasToDraw() {
        if (canvas.width == canvas1.width) {
            testRunner.notifyDone();
        } else {
            requestAnimationFrame(waitForCanvasToDraw);
        }
    }

    if (window.testRunner) {
        waitForCanvasToDraw();
    }
});
</script>
</body>
</html>

chromium/third_party/blink/web_tests/fast/canvas/OffscreenCanvas-Bitmaprenderer-resize.html