content/canvas/test/reftest/webgl-disable-test.html@6474c204b198
content/canvas/test/reftest/webgl-disable-test.html
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
1 <!DOCTYPE html>
2 <html class="reftest-wait">
3 <head>
4 <meta charset="UTF-8">
6 <script type="text/javascript" src="webgl-utils.js"></script>
7 <script type="text/javascript">
8 /* Disable Test
9 *
10 * If we succeed in getting a WebGL context, we will fill
11 * the canvas with red. If we fail to acquire a WebGL context,
12 * we will use Canvas2D to instead fill it with green.
13 *
14 * Note that this test differs from the others in that
15 * it will draw differently if it receives a WebGL context.
16 * Other tests are designed to fallback silently to Canvas2D.
17 *
18 * We use this test to assure that when we disable WebGL,
19 * WebGL does not function. This is trivially true for systems
20 * that don't support WebGL. This test is not viable for testing
21 * that WebGL works, as blocklisted systems will always draw green.
22 */
24 "use strict";
26 function renderGL(gl) {
27 gl.clearColor(1.0, 0.0, 0.0, 1.0);
28 gl.clear(gl.COLOR_BUFFER_BIT);
29 gl.finish();
30 }
32 function renderBackup(canvas) {
33 var context = canvas.getContext("2d");
34 context.fillStyle = "rgba(0, 255, 0, 1.0)";
35 context.fillRect(0, 0, 256, 256);
36 }
38 function runTest() {
39 var canvas = document.getElementById("canvas");
40 var gl = initGL(canvas);
42 if (gl)
43 renderGL(gl);
44 else
45 renderBackup(canvas);
47 waitForComposite(testComplete);
48 }
50 function testComplete() {
51 document.documentElement.removeAttribute("class");
52 }
53 </script>
54 </head>
56 <body onload="rAF(runTest);">
57 <canvas id="canvas" width="256" height="256"></canvas>
58 </body>
60 </html>
