dom/canvas/test/webgl-conf/checkout/conformance/buffers/buffer-uninitialized.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 <!DOCTYPE html>
   7 <html>
   8 <head>
   9 <meta charset="utf-8">
  10 <link rel="stylesheet" href="../../resources/js-test-style.css"/>
  11 <script src="../../js/js-test-pre.js"></script>
  12 <script src="../../js/webgl-test-utils.js"></script>
  13 </head>
  14 <body>
  15 <div id="description"></div>
  16 <div id="console"></div>
  17
  18 <canvas id="canvas" width="1" height="1"></canvas>
  19
  20 <script id="vshader" type="x-shader/x-vertex">
  21 attribute float a_vertex;
  22 void main()
  23 {
  24     gl_Position = a_vertex == 0.0 ? vec4(9, 9, 9, 1) : vec4(0.5, 0.5, 0.5, 1);
  25 }
  26 </script>
  27
  28 <script id="fshader" type="x-shader/x-fragment">
  29 void main()
  30 {
  31     gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
  32 }
  33 </script>
  34
  35 <script>
  36 "use strict";
  37 description("Tests that uninitialized WebGLBuffers are zeroed out");
  38
  39 var wtu = WebGLTestUtils;
  40 var gl = wtu.create3DContext(document.getElementById("canvas"));
  41 var program = wtu.setupProgram(gl, ["vshader", "fshader"], ["a_vertex"]);
  42 shouldBeTrue("program != null");
  43
  44 var TEST_LENGTH = 1024;
  45 var TEST_BUFSIZE = TEST_LENGTH * 4;
  46 var data = new Float32Array(TEST_LENGTH / 4); // this array is zeroed
  47
  48 var indices = new Uint16Array(TEST_LENGTH);
  49 for (var i = 0; i < TEST_LENGTH; i++) {
  50   indices[i] = i;
  51 }
  52
  53 gl.clearColor(0, 1, 0, 1);
  54
  55 function test(initFunction) {
  56   var uninitializedBuffer = gl.createBuffer();
  57   gl.bindBuffer(gl.ARRAY_BUFFER, uninitializedBuffer);
  58   initFunction();
  59
  60   var elements = gl.createBuffer();
  61   gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, elements);
  62   gl.bufferData(gl.ELEMENT_ARRAY_BUFFER, indices, gl.STATIC_DRAW);
  63
  64   gl.useProgram(program);
  65   var vertexLoc = gl.getAttribLocation(program, "a_vertex");
  66   gl.vertexAttribPointer(vertexLoc, 1, gl.FLOAT, gl.FALSE, 0, 0);
  67   gl.enableVertexAttribArray(vertexLoc);
  68
  69   wtu.glErrorShouldBe(gl, gl.NO_ERROR, "no error should result from setup");
  70
  71   gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
  72   gl.drawElements(gl.POINTS, TEST_LENGTH, gl.UNSIGNED_SHORT, 0);
  73   wtu.checkCanvasRect(gl, 0, 0, 1, 1, [0, 255, 0, 255], "buffer should be initialized to zero");
  74
  75   gl.deleteBuffer(uninitializedBuffer);
  76 }
  77
  78 var REPETITIONS = 50;
  79
  80 var j;
  81 debug("");
  82 debug("testing bufferData(..., size, ...)");
  83 for (j = 0; j < REPETITIONS; j++) {
  84   test(function() {
  85     gl.bufferData(gl.ARRAY_BUFFER, TEST_BUFSIZE, gl.STATIC_DRAW);
  86   });
  87 }
  88
  89 debug("");
  90 debug("testing bufferSubData(..., offset, data) of uninitialized buffer");
  91 for (j = 0; j < REPETITIONS; j++) {
  92   test(function() {
  93     gl.bufferData(gl.ARRAY_BUFFER, TEST_BUFSIZE, gl.STATIC_DRAW);
  94     // bufferSubData the second quarter of the buffer
  95     gl.bufferSubData(gl.ARRAY_BUFFER, TEST_BUFSIZE / 4, data);
  96   });
  97 }
  98
  99 var successfullyParsed = true;
 100 </script>
 101
 102 <script src="../../js/js-test-post.js"></script>
 103 </body>
 104 </html>