dom/canvas/test/webgl-conf/checkout/conformance2/renderbuffers/readbuffer.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
   7 <!DOCTYPE html>
   8 <html>
   9 <head>
  10 <meta charset="utf-8">
  11 <title>Test readBuffer Against WebGL 2</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 <div id="description"></div>
  18 <div id="console"></div>
  19 <canvas id="canvas" width="20" height="20"> </canvas>
  20 <script>
  21 "use strict";
  22 description("This tests reading from fbo");
  23
  24 var clearDrawingbuffer = function(color) {
  25   gl.clearColor(color[0] / 255, color[1] / 255, color[2] / 255, color[3] / 255);
  26   gl.clear(gl.COLOR_BUFFER_BIT);
  27 }
  28
  29 var validateReadingFromFramebuffer = function(color, expected, msg) {
  30   var pixels = new Uint8Array(1 * 1 * 4);
  31   gl.readPixels(0, 0, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, pixels);
  32   wtu.glErrorShouldBe(gl, expected, msg);
  33   if (expected == gl.NO_ERROR)
  34     wtu.checkCanvasRect(gl, 0, 0, canvas.width, canvas.height, color,
  35     "the color should be [" + color + "]");
  36 }
  37
  38 var setupRenderbuffer = function(attachment) {
  39   var renderbuffer = gl.createRenderbuffer();
  40   gl.bindRenderbuffer(gl.RENDERBUFFER, renderbuffer);
  41   gl.framebufferRenderbuffer(gl.FRAMEBUFFER, attachment, gl.RENDERBUFFER, renderbuffer);
  42   gl.renderbufferStorage(gl.RENDERBUFFER, gl.RGBA8, canvas.width, canvas.height);
  43   return renderbuffer;
  44 }
  45
  46 var testReadBufferOnDefaultFB = function() {
  47   gl.readBuffer(gl.NONE);
  48   wtu.glErrorShouldBe(gl, gl.NO_ERROR,
  49       "calling readBuffer with GL_NONE on the default framebuffer should succeed.");
  50   var pixels = new Uint8Array(1 * 1 * 4);
  51   gl.readPixels(0, 0, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, pixels);
  52   wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION,
  53       "should generate INVALID_OPERATION when reading from framebuffer and read buffer is GL_NONE.");
  54   gl.readBuffer(gl.BACK);
  55   wtu.glErrorShouldBe(gl, gl.NO_ERROR,
  56       "calling readBuffer with GL_BACK on the default framebuffer should succeed.");
  57
  58   gl.readBuffer(gl.COLOR_ATTACHMENT0);
  59   wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION,
  60       "calling readBuffer with GL_COLOR_ATTACHMENT0 on the default framebuffer should generate INVALID_OPERATION.");
  61 }
  62
  63 var testReadBufferOnFBO = function() {
  64   gl.readBuffer(gl.BACK);
  65   wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION,
  66       "calling readBuffer with GL_BACK on fbo should generate INVALID_OPERATION.");
  67
  68   gl.readBuffer(gl.NONE);
  69   wtu.glErrorShouldBe(gl, gl.NO_ERROR,
  70       "calling readBuffer with GL_NONE on fbo should succeed.");
  71   var pixels = new Uint8Array(1 * 1 * 4);
  72   gl.readPixels(0, 0, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, pixels);
  73   wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION,
  74       "should generate INVALID_OPERATION when reading from framebuffer and read buffer is GL_NONE.");
  75   gl.readBuffer(gl.COLOR_ATTACHMENT0);
  76   wtu.glErrorShouldBe(gl, gl.NO_ERROR,
  77       "calling readBuffer with GL_COLOR_ATTACHMENT0 on fbo should succeed.");
  78
  79   var maxColorAttachments = gl.getParameter(gl.MAX_COLOR_ATTACHMENTS);
  80   gl.readBuffer(gl.COLOR_ATTACHMENT0 + maxColorAttachments);
  81   wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION,
  82       "calling readBuffer with GL_COLOR_ATTACHMENTi that exceeds MAX_COLOR_ATTACHMENT on fbo should generate INVALID_OPERATION.");
  83   gl.readBuffer(gl.COLOR_ATTACHMENT1);
  84   wtu.glErrorShouldBe(gl, gl.NO_ERROR,
  85       "calling readBuffer with GL_COLOR_ATTACHMENT1 on the fbo should succeed.");
  86   shouldBe('gl.getParameter(gl.READ_BUFFER)', 'gl.COLOR_ATTACHMENT1');
  87 }
  88
  89 debug("");
  90 debug("Canvas.getContext");
  91
  92 var wtu = WebGLTestUtils;
  93 var canvas = document.getElementById("canvas");
  94 var gl = wtu.create3DContext(canvas, undefined, 2);
  95 if (!gl) {
  96   testFailed("context does not exist");
  97 } else {
  98   testPassed("context exists");
  99
 100   debug("");
 101   debug("Checking reading from framebuffer.");
 102
 103   // Test on the default framebuffer. Read buffer is GL_BACK by default.
 104   var backColor = [0, 0, 0, 255];
 105   clearDrawingbuffer(backColor);
 106   validateReadingFromFramebuffer(backColor, gl.NO_ERROR,
 107       "should be no errors when reading from GL_BACK on the default framebuffer.");
 108
 109   shouldBe('gl.getParameter(gl.READ_BUFFER)', 'gl.BACK');
 110   testReadBufferOnDefaultFB();
 111
 112   // Test on fbo. Read buffer is GL_COLOR_ATTACHMENT0 by default
 113   var fb = gl.createFramebuffer();
 114   gl.bindFramebuffer(gl.FRAMEBUFFER, fb);
 115   var colorbuffer = setupRenderbuffer(gl.COLOR_ATTACHMENT0);
 116   var red = [255, 0, 0, 255];
 117   clearDrawingbuffer(red);
 118   validateReadingFromFramebuffer(red, gl.NO_ERROR,
 119       "should be no errors when reading from GL_COLOR_ATTACHMENT0 on fbo.");
 120
 121   shouldBe('gl.getParameter(gl.READ_BUFFER)', 'gl.COLOR_ATTACHMENT0');
 122   testReadBufferOnFBO();
 123
 124   // Test on user defined read buffer (GL_COLOR_ATTACHMENT1) with or without corresponding image on fbo.
 125   gl.bindFramebuffer(gl.FRAMEBUFFER, fb);
 126   var colorbuffer1 = setupRenderbuffer(gl.COLOR_ATTACHMENT1);
 127   var green = [0, 255, 0, 255];
 128   gl.drawBuffers([gl.NONE, gl.COLOR_ATTACHMENT1]);
 129   clearDrawingbuffer(green);
 130   wtu.glErrorShouldBe(gl, gl.NO_ERROR, "should be no error after setup and clear render buffer");
 131   gl.readBuffer(gl.COLOR_ATTACHMENT1);
 132   validateReadingFromFramebuffer(green, gl.NO_ERROR,
 133       "should be no errors when reading from GL_COLOR_ATTACHMENT1 on fbo.");
 134   shouldBe('gl.getParameter(gl.READ_BUFFER)', 'gl.COLOR_ATTACHMENT1');
 135   // Need to reset draw buffers, otherwise it triggers a mac driver bug.
 136   // We add a separate test for that bug: conformance2/rendering/framebuffer-completeness-unaffected.html
 137   gl.drawBuffers([gl.COLOR_ATTACHMENT0]);
 138
 139   gl.framebufferRenderbuffer(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT1, gl.RENDERBUFFER, null)
 140   gl.readBuffer(gl.COLOR_ATTACHMENT1);
 141   validateReadingFromFramebuffer(null, gl.INVALID_OPERATION,
 142       "should generate INVALID_OPERATION when reading from GL_COLOR_ATTACHMENT1 but this attachment has no image currently.");
 143
 144   // switch to another fbo, read buffer is GL_COLOR_ATTACHMENT0, not GL_COLOR_ATTACHMENT1
 145   var fb1 = gl.createFramebuffer();
 146   gl.bindFramebuffer(gl.FRAMEBUFFER, fb1);
 147   var buffer = setupRenderbuffer(gl.COLOR_ATTACHMENT0);
 148   shouldBe('gl.getParameter(gl.READ_BUFFER)', 'gl.COLOR_ATTACHMENT0');
 149   var blue = [0, 0, 255, 255];
 150   clearDrawingbuffer(blue);
 151   validateReadingFromFramebuffer(blue, gl.NO_ERROR,
 152       "should be no errors when reading from GL_COLOR_ATTACHMENT0 on another fbo.");
 153
 154   // switch from fbo to default fb, read buffer will switch to GL_BACK from GL_COLOR_ATTACHMENT0
 155   gl.bindFramebuffer(gl.FRAMEBUFFER, null);
 156   shouldBe('gl.getParameter(gl.READ_BUFFER)', 'gl.BACK');
 157   validateReadingFromFramebuffer(backColor, gl.NO_ERROR,
 158       "should be no errors when reading from GL_BACK on the default framebuffer.");
 159
 160   gl.deleteFramebuffer(fb);
 161   gl.deleteRenderbuffer(colorbuffer);
 162   gl.deleteRenderbuffer(colorbuffer1);
 163   gl.deleteFramebuffer(fb1);
 164   gl.deleteRenderbuffer(buffer);
 165 }
 166
 167 debug("");
 168 var successfullyParsed = true;
 169
 170 </script>
 171 <script src="../../js/js-test-post.js"></script>
 172
 173 </body>
 174 </html>