gl-pixelstorei.html (2866B)
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 7 <!DOCTYPE html> 8 <html> 9 <head> 10 <meta charset="utf-8"> 11 <title>WebGL pixelStorei Test</title> 12 <link rel="stylesheet" href="../../../resources/js-test-style.css"/> 13 <script src="../../../js/js-test-pre.js"></script> 14 <script src="../../../js/webgl-test-utils.js"></script> 15 </head> 16 <body> 17 <canvas id="example" width="50" height="50"></canvas> 18 <canvas id="2d00" width="50" height="50"></canvas> 19 <canvas id="2d01" width="50" height="50"></canvas> 20 <canvas id="2d02" width="50" height="50"></canvas> 21 <canvas id="2d03" width="50" height="50"></canvas> 22 <div id="description"></div> 23 <div id="console"></div> 24 <script id="vshader" type="x-shader/x-vertex"> 25 attribute vec4 vPosition; 26 void main() { 27 gl_Position = vPosition; 28 } 29 </script> 30 31 <script id="fshader" type="x-shader/x-fragment"> 32 void main() { 33 gl_FragColor = vec4(1.0,0.0,0.0,1.0); 34 } 35 </script> 36 37 <script> 38 "use strict"; 39 function init() { 40 description("This test checks that drawImage and readPixels are not effected by gl.Pixelstorei(gl.PACK_ALIGNMENT) and visa versa"); 41 42 debug("There should be 5 red triangles on 5 black squares above"); 43 debug(""); 44 45 var wtu = WebGLTestUtils; 46 var canvas3d = document.getElementById("example"); 47 var gl = wtu.create3DContext("example"); 48 var program = wtu.setupProgram(gl, ["vshader", "fshader"], ["vPosition"]); 49 50 var vertexObject = gl.createBuffer(); 51 gl.bindBuffer(gl.ARRAY_BUFFER, vertexObject); 52 gl.bufferData(gl.ARRAY_BUFFER, new Float32Array([ 0,0.5,0, -0.5,-0.5,0, 0.5,-0.5,0 ]), gl.STATIC_DRAW); 53 gl.enableVertexAttribArray(0); 54 gl.vertexAttribPointer(0, 3, gl.FLOAT, false, 0, 0); 55 56 gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT); 57 gl.drawArrays(gl.TRIANGLES, 0, 3); 58 59 function checkData(ctx, name) { 60 // Test several locations 61 // First line should be all black 62 wtu.checkCanvasRect(ctx, 0, 0, 50, 1, [0, 0, 0, 0]); 63 64 // Line 25 should be red for at least 6 red pixels starting 22 pixels in 65 wtu.checkCanvasRect(ctx, 22, 25, 6, 1, [255, 0, 0, 255]); 66 67 // Last line should be all black 68 wtu.checkCanvasRect(ctx, 0, 49, 50, 1, [0, 0, 0, 0]); 69 } 70 71 var ctx2d; 72 73 function checkColors() { 74 checkData(gl, "3d context"); 75 checkData(ctx2d, "2d context"); 76 } 77 78 var table = [1, 2, 4, 8]; 79 for (var ii = 0; ii < table.length; ++ii) { 80 gl.pixelStorei(gl.PACK_ALIGNMENT, table[ii]); 81 ctx2d = document.getElementById("2d0" + ii).getContext("2d"); 82 ctx2d.globalCompositeOperation = 'copy'; 83 ctx2d.drawImage(canvas3d, 0, 0); 84 checkColors(); 85 assertMsg(gl.getParameter(gl.PACK_ALIGNMENT) == table[ii], 86 "PACK_ALIGNMENT is " + table[ii]); 87 } 88 } 89 90 init(); 91 var successfullyParsed = true; 92 </script> 93 <script src="../../../js/js-test-post.js"></script> 94 95 </body> 96 </html>