dom/canvas/test/webgl-conf/checkout/conformance/rendering/scissor-rect-repeated-rendering.html

   1 <!--
   2 Copyright (c) 2019 The Khronos Group Inc.
   3 Use of this source code is governed by an MIT-style license that can be
   4 found in the LICENSE.txt file.
   5 -->
   6
   7 <!DOCTYPE html>
   8 <html>
   9 <head>
  10 <meta charset="utf-8">
  11 <title>Scissor Rectangle Repeated Rendering Test</title>
  12 <link rel="stylesheet" href="../../resources/js-test-style.css"/>
  13 <script src="../../js/js-test-pre.js"></script>
  14 <script src="../../js/webgl-test-utils.js"> </script>
  15 </head>
  16 <body>
  17 <canvas id="example" width="128" height="128"></canvas>
  18 <div id="description"></div>
  19 <div id="console"></div>
  20 <script>
  21 "use strict";
  22
  23 description();
  24 debug('Regression test for <a href="https://code.google.com/p/chromium/issues/detail?id=778770">Chromium bug 778770</a>');
  25
  26 var wtu = WebGLTestUtils;
  27
  28 // These context creation attributes are significant to reproduce the bug.
  29 var gl = wtu.create3DContext("example", {alpha: false, antialias: false});
  30
  31 // Draw into the upper right quadrant.
  32 var x      = 64;
  33 var y      = 64;
  34 var width  = 64;
  35 var height = 64;
  36
  37 var numRenders = 10;
  38
  39 function render() {
  40     gl.viewport(x, y, width, height);
  41     gl.scissor(x, y, width, height);
  42     gl.enable(gl.SCISSOR_TEST);
  43     gl.clearColor(0.0, 1.0, 0.0, 1.0);
  44     gl.clear(gl.COLOR_BUFFER_BIT);
  45
  46     // If anything but black is ever seen in the un-drawn region of
  47     // the canvas, the test fails.
  48     var black = [0, 0, 0, 255];
  49     wtu.checkCanvasRect(gl, 10, 10, 10, 10, black, "should be black", 1);
  50
  51     if (--numRenders > 0) {
  52         window.requestAnimationFrame(render);
  53     } else {
  54         finishTest();
  55     }
  56 }
  57
  58 window.requestAnimationFrame(render);
  59
  60 var successfullyParsed = true;
  61 </script>
  62 </body>
  63 </html>