dom/canvas/test/webgl-conf/checkout/conformance2/rendering/out-of-bounds-index-buffers-after-copying.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 <title>WebGL Out-of-Bounds Index Buffer Caused by CopyBufferSubData Conformance Test</title>
  14 </head>
  15 <body>
  16 <canvas id="canvas" width="8" height="8" style="width: 100px; height: 100px;"></canvas>
  17 <div id="description"></div>
  18 <div id="console"></div>
  19 <script id="vsCheckOutOfBounds" type="x-shader/x-vertex">
  20     #define TEST_CASE_IN_BOUND 1
  21     #define TEST_CASE_OUT_OF_BOUND 2
  22
  23     precision mediump float;
  24     attribute vec2 position;
  25     attribute vec4 vecRandom;
  26     varying vec4 v_color;
  27     uniform int u_testCase;
  28
  29     bool testFloatComponentAccurate(float component) {
  30         return component == 0.2;
  31     }
  32     // Per the spec, each component can either contain existing contents
  33     // of the buffer or 0.
  34     bool testFloatComponent(float component) {
  35         return (component == 0.2 || component == 0.0);
  36     }
  37     // The last component is additionally allowed to be 1.0.
  38     bool testLastFloatComponent(float component) {
  39         return testFloatComponent(component) || component == 1.0;
  40     }
  41
  42     bool testData(vec4 data) {
  43         if (u_testCase == TEST_CASE_IN_BOUND) {
  44             return (testFloatComponentAccurate(data.x) &&
  45                     testFloatComponentAccurate(data.y) &&
  46                     testFloatComponentAccurate(data.z) &&
  47                     testFloatComponentAccurate(data.w));
  48         } else if (u_testCase == TEST_CASE_OUT_OF_BOUND) {
  49             return (testFloatComponent(data.x) &&
  50                     testFloatComponent(data.y) &&
  51                     testFloatComponent(data.z) &&
  52                     testLastFloatComponent(data.w));
  53         }
  54         return false;
  55     }
  56
  57     void main() {
  58         if (testData(vecRandom)) {
  59             v_color = vec4(0.0, 1.0, 0.0, 1.0); // green -- We're good
  60         } else {
  61             v_color = vec4(1.0, 0.0, 0.0, 1.0); // red -- Unexpected value
  62         }
  63         gl_Position = vec4(position, 0.0, 1.0);
  64     }
  65 </script>
  66 <script>
  67 "use strict";
  68 description("This test verifies that out-of-bounds index buffers caused by CopyBufferSubData behave according to spec.");
  69
  70 // Ensure that drawElements flags either no error or INVALID_OPERATION. In the case of INVALID_OPERATION,
  71 // no canvas pixels can be touched.  In the case of NO_ERROR, all written values must either be the
  72 // zero vertex or a value in the vertex buffer.  See vsCheckOutOfBounds shader.
  73 function verifyOutOfBoundsIndex(gl) {
  74     var error = gl.getError();
  75     if (error === gl.INVALID_OPERATION) {
  76         testPassed("drawElements flagged INVALID_OPERATION, which is valid so long as all canvas pixels were not touched.");
  77         wtu.checkCanvas(gl, [0, 0, 255, 255]);
  78     } else if (error === gl.NO_ERROR) {
  79         testPassed("drawElements flagged NO_ERROR, which is valid so long as all canvas pixels are green.");
  80         wtu.checkCanvas(gl, [0, 255, 0, 255]);
  81     } else {
  82         testFailed("Invalid error flagged by drawElements. Should be INVALID_OPERATION or NO_ERROR");
  83     }
  84 }
  85
  86 // Create an element array buffer with a tri-strip that starts at startIndex and make
  87 // it the active element array buffer.
  88 function prepareElementArrayBuffer(gl, startIndex) {
  89     var glElementArrayBuffer = gl.createBuffer();
  90     gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, glElementArrayBuffer);
  91     var quadIndices = new Uint16Array(4);
  92     for (var i = 0; i < quadIndices.length; i++) {
  93         quadIndices[i] = startIndex + i;
  94     }
  95     gl.bufferData(gl.ELEMENT_ARRAY_BUFFER, quadIndices, gl.STATIC_DRAW);
  96     return glElementArrayBuffer;
  97 }
  98
  99
 100 var wtu = WebGLTestUtils;
 101 var canvas = document.getElementById("canvas");
 102 var gl = wtu.create3DContext(canvas, {antialias: false}, 2);
 103
 104 var numberOfQuads = 200;
 105
 106 // Create a vertex buffer with 200 properly formed tri-strip quads. These quads will cover the canvas texture
 107 // such that every single pixel is touched by the fragment shader.
 108 var quadBuffer = gl.createBuffer();
 109 gl.bindBuffer(gl.ARRAY_BUFFER, quadBuffer);
 110 var quadPositions = new Float32Array(numberOfQuads * /*ComponentsPerQuad*/2 * /*VerticesPerQuad*/4);
 111 for (var i = 0; i < quadPositions.length; i += /*ComponentsPerQuad*/2 * /*VerticesPerQuad*/4) {
 112     quadPositions[i+0] = -1.0;  // upper left
 113     quadPositions[i+1] =  1.0;
 114     quadPositions[i+2] =  1.0;  // upper right
 115     quadPositions[i+3] =  1.0;
 116     quadPositions[i+4] = -1.0;  // lower left
 117     quadPositions[i+5] = -1.0;
 118     quadPositions[i+6] =  1.0;  // lower right
 119     quadPositions[i+7] = -1.0;
 120 }
 121 gl.bufferData(gl.ARRAY_BUFFER, quadPositions, gl.STATIC_DRAW);
 122 gl.enableVertexAttribArray(0);
 123 gl.vertexAttribPointer(0, 2, gl.FLOAT, false, 0, 0);
 124
 125 // Create a small vertex buffer with determined-ahead-of-time "random" values (0.2). This buffer will be
 126 // the one indexed off the end.
 127 var vertexBuffer = gl.createBuffer();
 128 gl.bindBuffer(gl.ARRAY_BUFFER, vertexBuffer);
 129 gl.bufferData(gl.ARRAY_BUFFER,
 130               new Float32Array([0.2, 0.2, 0.2, 0.2,
 131                                 0.2, 0.2, 0.2, 0.2,
 132                                 0.2, 0.2, 0.2, 0.2,
 133                                 0.2, 0.2, 0.2, 0.2]),
 134               gl.STATIC_DRAW);
 135 gl.enableVertexAttribArray(1);
 136 gl.vertexAttribPointer(1, 4, gl.FLOAT, false, 0, 0);
 137
 138 // Setup the verification program.
 139 var program = wtu.setupProgram(gl, ["vsCheckOutOfBounds", wtu.simpleVertexColorFragmentShader], ["position", "vecRandom"]);
 140 wtu.glErrorShouldBe(gl, gl.NO_ERROR, "Shader and buffer setup should generate no errors");
 141 var loc = gl.getUniformLocation(program, "u_testCase");
 142 shouldBeNonNull(loc);
 143
 144 debug("");
 145 debug("Test -- Vertex indices are in bounds.");
 146 gl.uniform1i(loc, 1);  // TEST_CASE_IN_BOUND == 1
 147 gl.clearColor(0.0, 0.0, 1.0, 1.0);  // Start with blue to indicate no pixels touched.
 148 gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
 149 var elementArrayBuffer = prepareElementArrayBuffer(gl, /*StartIndex*/0);
 150 gl.drawElements(gl.TRIANGLE_STRIP, 4, gl.UNSIGNED_SHORT, /*offset*/0);
 151 wtu.glErrorShouldBe(gl, gl.NO_ERROR, "Draw call should generate no errors");
 152 wtu.checkCanvas(gl, [0, 255, 0, 255]);
 153
 154 debug("");
 155 debug("Test -- Index off the end of the vertex buffer near the beginning of the out of bounds area.");
 156 gl.uniform1i(loc, 2);  // TEST_CASE_OUT_OF_BOUND == 2
 157 gl.clearColor(0.0, 0.0, 1.0, 1.0);  // Start with blue to indicate no pixels touched.
 158 gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
 159 var outOfBoundsElementArrayBuffer = prepareElementArrayBuffer(gl, /*StartIndex*/4);
 160 gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, outOfBoundsElementArrayBuffer);
 161 gl.bindBuffer(gl.COPY_WRITE_BUFFER, elementArrayBuffer);
 162 gl.copyBufferSubData(gl.ELEMENT_ARRAY_BUFFER, gl.COPY_WRITE_BUFFER, 0, 0, 4 * Uint16Array.BYTES_PER_ELEMENT);
 163 wtu.glErrorShouldBe(gl, gl.NO_ERROR, "copyBufferSubData should generate no errors");
 164 gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, elementArrayBuffer);
 165 gl.drawElements(gl.TRIANGLE_STRIP, 4, gl.UNSIGNED_SHORT, /*offset*/0);
 166 verifyOutOfBoundsIndex(gl);
 167
 168 debug("");
 169 debug("Test -- Index off the end of the vertex buffer near the end of the out of bounds area.")
 170 gl.uniform1i(loc, 2);  // TEST_CASE_OUT_OF_BOUND == 2
 171 gl.clearColor(0.0, 0.0, 1.0, 1.0);  // Start with blue to indicate no pixels touched.
 172 gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
 173 outOfBoundsElementArrayBuffer = prepareElementArrayBuffer(gl, /*StartIndex*/numberOfQuads - 4);
 174 gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, elementArrayBuffer);
 175 gl.bindBuffer(gl.COPY_READ_BUFFER, outOfBoundsElementArrayBuffer);
 176 gl.copyBufferSubData(gl.COPY_READ_BUFFER, gl.ELEMENT_ARRAY_BUFFER, 0, 0, 4 * Uint16Array.BYTES_PER_ELEMENT);
 177 wtu.glErrorShouldBe(gl, gl.NO_ERROR, "copyBufferSubData should generate no errors");
 178 gl.drawElements(gl.TRIANGLE_STRIP, 4, gl.UNSIGNED_SHORT, /*offset*/0);
 179 verifyOutOfBoundsIndex(gl);
 180
 181 debug("");
 182 wtu.glErrorShouldBe(gl, gl.NO_ERROR, "Running tests should generate no errors");
 183 var successfullyParsed = true;
 184 </script>
 185 <script src="../../js/js-test-post.js"></script>
 186 </body>
 187 </html>