<!DOCTYPE HTML>
<html>
<head>
<title>Low Latency Canvas 2D Test: Green and blue box, over large red box, over black</title>
<style type="text/css">
.nomargin {
margin: 0px auto;
}
</style>
<script>
let g_swapsBeforeAck = 15;
let g_canvas;
let g_c2d;
function main()
{
g_canvas = document.getElementById("c");
g_c2d = g_canvas.getContext("2d", {desynchronized: true});
draw();
}
function draw()
{
g_c2d.clearRect(0, 0, g_canvas.width, g_canvas.height);
g_c2d.fillStyle = "red";
g_c2d.fillRect(10, 10, 80, 80);
requestAnimationFrame(draw2);
}
function draw2()
{
// Verify that incremental painting works.
g_c2d.fillStyle = "green";
g_c2d.fillRect(20, 20, 30, 30);
// Verify that output doesn't get flipped vertically.
g_c2d.fillStyle = "blue";
g_c2d.fillRect(50, 50, 30, 30);
waitForFinish();
}
function waitForFinish()
{
if (g_swapsBeforeAck == 0) {
domAutomationController.send("SUCCESS");
} else {
g_swapsBeforeAck--;
window.requestAnimationFrame(waitForFinish);
}
}
</script>
</head>
<body onload="main()" class="nomargin">
<canvas id="c" width="100" height="100" class="nomargin" style="background-color:black"></canvas>
</body>
</html>