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content / test / data / gpu / pixel_canvas_low_latency_webgl_draw_image.html [blame]
<!DOCTYPE HTML>
<html>
<head>
<title>Low Latency WebGL Canvas drawImage Test</title>
<style type="text/css">
.nomargin {
margin: 0px auto;
}
</style>
<script>
let g_swapsBeforeAck = 15;
function waitForFinish()
{
if (g_swapsBeforeAck == 0) {
domAutomationController.send("SUCCESS");
} else {
g_swapsBeforeAck--;
window.requestAnimationFrame(waitForFinish);
}
}
function main()
{
let canvas_gl = document.getElementById("c3d");
let gl = canvas_gl.getContext("webgl", {"desynchronized": true});
let width = canvas_gl.width;
let height = canvas_gl.height;
gl.enable(gl.SCISSOR_TEST);
gl.scissor(0, 0, width, height);
gl.clearColor(1, 0, 0, 1);
gl.clear(gl.COLOR_BUFFER_BIT);
gl.scissor(0, 0, width / 2, height / 2);
gl.clearColor(0, 1, 0, 1);
gl.clear(gl.COLOR_BUFFER_BIT);
gl.scissor(width / 2, height / 2, width / 2, height / 2);
gl.clearColor(0, 0, 1, 1);
gl.clear(gl.COLOR_BUFFER_BIT);
let canvas_2d = document.getElementById("c2d");
let ctx_2d = canvas_2d.getContext("2d");
ctx_2d.drawImage(canvas_gl, 0, 0);
waitForFinish();
}
</script>
</head>
<body onload="main()">
<div id="container" style="position:absolute; top:0px; left:0px">
<canvas id="c3d" width="100" height="100" class="nomargin"></canvas>
<canvas id="c2d" width="100" height="100" class="nomargin"></canvas>
</div>
</body>
</html>