third_party/WebKit/LayoutTests/fast/canvas/webgl/framebuffer-bindings-unaffected-on-resize.html

   1
   2 <!DOCTYPE html>
   3 <html>
   4 <head>
   5 <meta charset="utf-8">
   6 <title>Verifies that GL framebuffer bindings do not change when canvas is resized</title>
   7 <script src="../../../resources/js-test.js"></script>
   8 <script src="resources/webgl-test.js"></script>
   9 <script src="resources/webgl-test-utils.js"></script>
  10 </head>
  11 <body>
  12 <canvas id="example" width="4px" height="4px"></canvas>
  13 <div id="description"></div>
  14 <div id="console"></div>
  15 <script>
  16 description("Verifies that GL framebuffer bindings do not change when canvas is resized");
  17
  18 if (window.initNonKhronosFramework) {
  19   window.initNonKhronosFramework(true);
  20 }
  21
  22 var err;
  23 var wtu = WebGLTestUtils;
  24 var canvas = document.getElementById("example");
  25 var gl = wtu.create3DContext(canvas);
  26 var green = [0, 255, 0, 255];
  27 var blue = [0, 0, 255, 255];
  28 var fboSize = 2;
  29 shouldBeTrue("fboSize < canvas.width");
  30 var fbo = gl.createFramebuffer();
  31 gl.bindFramebuffer(gl.FRAMEBUFFER, fbo);
  32 var fboTex = gl.createTexture();
  33 gl.activeTexture(gl.TEXTURE1);
  34 gl.bindTexture(gl.TEXTURE_2D, fboTex);
  35 gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, fboTex, 0);
  36 gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, fboSize, fboSize, 0, gl.RGBA, gl.UNSIGNED_BYTE, null);
  37 gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR);
  38 gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
  39 gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
  40 gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
  41 shouldBe("gl.checkFramebufferStatus(gl.FRAMEBUFFER)", "gl.FRAMEBUFFER_COMPLETE");
  42
  43 function checkFBO(color, msg) {
  44   wtu.checkCanvasRect(gl, 0, 0, fboSize, fboSize, color, msg);
  45   wtu.checkCanvasRect(gl, fboSize, fboSize, fboSize, fboSize, [0, 0, 0, 0], "area outside fbo should be transparent black");
  46 }
  47
  48 // The FBO is 2x2 and it's bound so clearing should clear a 2x2 area
  49 // and calling read pixels should read the clear color in that 2x2 area
  50 // and 0,0,0,0 outside that area.
  51 //
  52 // If the FBO is no longer bound because of a WebGL implementation error
  53 // then likely the clear will clear the backbuffer and reading outside
  54 // the 2x2 area will not be 0,0,0,0
  55
  56 function test() {
  57   gl.clearColor(0, 0, 1, 1);
  58   gl.clear(gl.COLOR_BUFFER_BIT);
  59   checkFBO(blue, "should be blue");
  60   gl.clearColor(0, 1, 0, 1);
  61   gl.clear(gl.COLOR_BUFFER_BIT);
  62   checkFBO(green, "should be green");
  63 }
  64
  65 debug("test before resizing canvas");
  66 test();
  67 debug("test after resizing canvas");
  68 canvas.width = 8;
  69 test();
  70 debug("test after resizing canvas and waiting for compositing");
  71 canvas.width = 16;
  72 wtu.waitForComposite(5, function() {
  73   test();
  74   finishTest();
  75   glErrorShouldBe(gl, gl.NO_ERROR, "Should be no errors.");
  76 });
  77
  78 successfullyParsed = true;
  79 </script>
  80 </body>
  81 </html>
  82