third_party/WebKit/LayoutTests/fast/canvas/webgl/webgl-large-texture.html

   1 <!DOCTYPE html>
   2 <html>
   3 <head>
   4 <meta charset="utf-8">
   5 <title>Loading a large texture using texImage2D</title>
   6 <script src="../../../resources/js-test.js"></script>
   7 <script src="resources/webgl-test.js"></script>
   8 </head>
   9
  10 <body>
  11 <canvas id="canvas" width="64" height="64"></canvas>
  12 <div id="description"></div>
  13 <div id="console"></div>
  14
  15 <script>
  16 var successfullyParsed = false;
  17
  18 function init()
  19 {
  20     if (window.initNonKhronosFramework)
  21         window.initNonKhronosFramework(true);
  22
  23     if (window.internals)
  24         window.internals.settings.setWebGLErrorsToConsoleEnabled(false);
  25
  26     description('Test loading a large texture using texImage2D');
  27
  28     runTest();
  29 }
  30
  31 function andPixels(pixels32) {
  32   var pixelsAnd = 0xffffffff;
  33   for (var i = 0; i < pixels32.length; ++i) {
  34     pixelsAnd &= pixels32[i];
  35   }
  36   return pixelsAnd;
  37 }
  38
  39 function runTest() {
  40   var width = 3900;
  41   var height = 3900;
  42
  43   var canvas = document.getElementById('canvas');
  44   var gl = canvas.getContext('webgl');
  45
  46   gl.pixelStorei(gl.UNPACK_COLORSPACE_CONVERSION_WEBGL, gl.NONE);
  47
  48   var texture = gl.createTexture();
  49   gl.bindTexture(gl.TEXTURE_2D, texture);
  50
  51   var image = new Image();
  52   image.onerror = function (e) {
  53     testFailed('Image failed to load');
  54   }
  55   image.onload = function () {
  56     debug('Image width and height: ' + image.width + ', ' + image.height);
  57
  58     if (image.width !== width || image.height !== height) {
  59       testFailed('Image did not have expected dimensions.');
  60       return;
  61     }
  62
  63     var pixels = new ArrayBuffer(width * height * 4);
  64     var pixels8 = new Uint8Array(pixels);
  65     var pixels32 = new Uint32Array(pixels);
  66
  67     if (width > gl.getParameter(gl.MAX_TEXTURE_SIZE) ||
  68         width > gl.getParameter(gl.MAX_RENDERBUFFER_SIZE)) {
  69       // The image is allowed to be too big to be used as a texture.
  70       finishJSTest();
  71       return;
  72     }
  73
  74     gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.RGBA, gl.UNSIGNED_BYTE, image);
  75     if (gl.getError() != gl.NO_ERROR) {
  76       // Loading the texture is allowed to fail due to resource constraints.
  77       finishJSTest();
  78       return;
  79     }
  80     var fb = gl.createFramebuffer();
  81     gl.bindFramebuffer(gl.FRAMEBUFFER, fb);
  82     gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, texture, 0);
  83     gl.readPixels(0, 0, width, height, gl.RGBA, gl.UNSIGNED_BYTE, pixels8);
  84
  85     // The image is filled with white, ignore last bit of each subpixel to account for decoding rounding differences.
  86     if ((andPixels(pixels32) & 0xfefefefe) !== (0xfefefefe | 0)) {
  87       testFailed('Texture was not loaded correctly.');
  88     }
  89
  90     finishJSTest();
  91   }
  92   image.src = 'resources/white3900x3900.jpg';
  93 }
  94
  95 init();
  96 </script>
  97 </body>
  98 </html>