third_party/WebKit/LayoutTests/fast/canvas/webgl/framebuffer-bindings-affected-by-to-data-url.html

   1 <!DOCTYPE html>
   2 <html>
   3 <body>
   4 <canvas id="example" width="50" height="50">
   5 </canvas>
   6 <div id="description"></div>
   7 <div id="console"></div>
   8 <script src="../../../resources/js-test.js"></script>
   9 <script src="resources/webgl-test.js"></script>
  10 <script src="resources/webgl-test-utils.js"></script>
  11 <script>
  12 "use strict";
  13 var wtu = WebGLTestUtils;
  14 description("toDataURL() causes side effect for framebuffer binding. crbug.com/445848");
  15
  16 function test() {
  17   var glCanvas = document.getElementById("example");
  18   // crbug.com/445848 bug occurs only on the following webgl configuration.
  19   var gl = wtu.create3DContext(glCanvas, {preserveDrawingBuffer: true, premultipliedAlpha: true});
  20   // FIXME: context.getContextAttributes().antialias is always false on
  21   // content shell with --run-layout-test option. See http://crbug.com/375682
  22   // If antialias is supported, test can be much shorter for crbug.com/445848.
  23
  24   var program = wtu.setupColorQuad(gl);
  25
  26   // Clear backbuffer in red.
  27   gl.clearColor(1.0, 0.0, 0.0, 1.0);
  28   gl.clear(gl.COLOR_BUFFER_BIT);
  29   wtu.checkCanvas(gl, [255, 0, 0, 255], "should be red");
  30
  31   var fbo = gl.createFramebuffer();
  32   var tex = gl.createTexture();
  33   gl.bindTexture(gl.TEXTURE_2D, tex);
  34   gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, 50, 50, 0, gl.RGBA, gl.UNSIGNED_BYTE, null);
  35   gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST);
  36   gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST);
  37   gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
  38   gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
  39   gl.bindFramebuffer(gl.FRAMEBUFFER, fbo);
  40   gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, tex, 0);
  41   if (gl.checkFramebufferStatus(gl.FRAMEBUFFER) != gl.FRAMEBUFFER_COMPLETE) {
  42     finishTest();
  43     return;
  44   }
  45
  46   // Clear the FBO in green.
  47   gl.clearColor(0.0, 1.0, 0.0, 1.0);
  48   gl.clear(gl.COLOR_BUFFER_BIT);
  49
  50   // backbuffer is still in red.
  51   gl.bindFramebuffer(gl.FRAMEBUFFER, null);
  52   wtu.checkCanvas(gl, [255, 0, 0, 255], "should be red");
  53   gl.bindFramebuffer(gl.FRAMEBUFFER, fbo);
  54
  55   glCanvas.toDataURL();
  56   // The second toDataURL binds backbuffer in crbug.com/445848
  57   glCanvas.toDataURL();
  58   // It applies to backbuffer, not the FBO.
  59   gl.clear(gl.COLOR_BUFFER_BIT);
  60
  61   // backbuffer must be in red, not green.
  62   gl.bindFramebuffer(gl.FRAMEBUFFER, null);
  63   wtu.checkCanvas(gl, [255, 0, 0, 255], "should be red");
  64
  65   finishTest();
  66 }
  67 test();
  68
  69 var successfullyParsed = true;
  70 </script>
  71 </body>
  72 </html>