third_party/WebKit/PerformanceTests/Canvas/upload-canvas-2d-to-texture.html

   1 <!DOCTYPE html>
   2 <html>
   3 <body>
   4 <script src="../resources/runner.js"></script>
   5 <script src="resources/canvas_runner.js"></script>
   6 <script>
   7
   8 var canvas2D = document.createElement("canvas");
   9 var ctx2D = canvas2D.getContext("2d");
  10 var canvas3D = document.createElement('canvas');
  11 var gl = canvas3D.getContext('webgl');
  12 if(!gl)
  13     CanvasRunner.logFatalError("\nWebGL is not supported or enabled on this platform!\n");
  14 var tex = null;
  15
  16 function setSize(width, height) {
  17     canvas2D.width = width;
  18     canvas2D.height = height;
  19     canvas3D.width = width;
  20     canvas3D.height = height;
  21 }
  22
  23 function rand(range) {
  24     return Math.floor(Math.random() * range);
  25 }
  26
  27 function fillCanvas(ctx2d, canvas2d) {
  28     ctx2d.fillStyle = "rgba(" + rand(255) + "," + rand(255) + "," + rand(255)  + "," + rand(255) + ")";
  29     ctx2d.fillRect(0, 0, canvas2d.width, canvas2d.height);
  30 }
  31
  32 function preRun() {
  33     tex = gl.createTexture();
  34     gl.bindTexture(gl.TEXTURE_2D, tex);
  35 }
  36
  37 function doRun() {
  38     gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.RGBA, gl.UNSIGNED_BYTE, canvas2D);
  39 }
  40
  41 function ensureComplete() {
  42     gl.readPixels(0, 0, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, new Uint8Array(4));
  43 }
  44
  45 function postRun() {
  46     gl.deleteTexture(tex);
  47 }
  48
  49 window.onload = function () {
  50     setSize(1024, 1024);
  51     fillCanvas(ctx2D, canvas2D);
  52     CanvasRunner.start({
  53         description: "This bench test checks the speed on uploading 2d Canvas(1024x1024) to Webgl Texture(1024x1024).",
  54         preRun: preRun,
  55         doRun: doRun,
  56         ensureComplete: ensureComplete,
  57         postRun: postRun});
  58 }
  59
  60 </script>
  61 </body>
  62 </html>