LayoutTests/webgl/resources/webgl_test_files/conformance2/renderbuffers/readbuffer.html - WebKit - Git at Google

 <!--
 Copyright (c) 2019 The Khronos Group Inc.
 Use of this source code is governed by an MIT-style license that can be
 found in the LICENSE.txt file.
 -->

 <!DOCTYPE html>
 <html>
 <head>
 <meta charset="utf-8">
 <title>Test readBuffer Against WebGL 2</title>
 <link rel="stylesheet" href="../../resources/js-test-style.css"/>
 <script src="../../js/js-test-pre.js"></script>
 <script src="../../js/webgl-test-utils.js"></script>
 </head>
 <body>
 <div id="description"></div>
 <div id="console"></div>
 <canvas id="canvas" width="20" height="20"> </canvas>
 <script>
 "use strict";
 description("This tests reading from fbo");

 var clearDrawingbuffer = function(color) {
   gl.clearColor(color[0] / 255, color[1] / 255, color[2] / 255, color[3] / 255);
   gl.clear(gl.COLOR_BUFFER_BIT);
 }

 var validateReadingFromFramebuffer = function(color, expected, msg) {
   var pixels = new Uint8Array(1 * 1 * 4);
   gl.readPixels(0, 0, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, pixels);
   wtu.glErrorShouldBe(gl, expected, msg);
   if (expected == gl.NO_ERROR)
     wtu.checkCanvasRect(gl, 0, 0, canvas.width, canvas.height, color,
     "the color should be [" + color + "]");
 }

 var setupRenderbuffer = function(attachment) {
   var renderbuffer = gl.createRenderbuffer();
   gl.bindRenderbuffer(gl.RENDERBUFFER, renderbuffer);
   gl.framebufferRenderbuffer(gl.FRAMEBUFFER, attachment, gl.RENDERBUFFER, renderbuffer);
   gl.renderbufferStorage(gl.RENDERBUFFER, gl.RGBA8, canvas.width, canvas.height);
   return renderbuffer;
 }

 var testReadBufferOnDefaultFB = function() {
   gl.readBuffer(gl.NONE);
   wtu.glErrorShouldBe(gl, gl.NO_ERROR,
       "calling readBuffer with GL_NONE on the default framebuffer should succeed.");
   var pixels = new Uint8Array(1 * 1 * 4);
   gl.readPixels(0, 0, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, pixels);
   wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION,
       "should generate INVALID_OPERATION when reading from framebuffer and read buffer is GL_NONE.");
   gl.readBuffer(gl.BACK);
   wtu.glErrorShouldBe(gl, gl.NO_ERROR,
       "calling readBuffer with GL_BACK on the default framebuffer should succeed.");

   gl.readBuffer(gl.COLOR_ATTACHMENT0);
   wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION,
       "calling readBuffer with GL_COLOR_ATTACHMENT0 on the default framebuffer should generate INVALID_OPERATION.");
 }

 var testReadBufferOnFBO = function() {
   gl.readBuffer(gl.BACK);
   wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION,
       "calling readBuffer with GL_BACK on fbo should generate INVALID_OPERATION.");

   gl.readBuffer(gl.NONE);
   wtu.glErrorShouldBe(gl, gl.NO_ERROR,
       "calling readBuffer with GL_NONE on fbo should succeed.");
   var pixels = new Uint8Array(1 * 1 * 4);
   gl.readPixels(0, 0, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, pixels);
   wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION,
       "should generate INVALID_OPERATION when reading from framebuffer and read buffer is GL_NONE.");
   gl.readBuffer(gl.COLOR_ATTACHMENT0);
   wtu.glErrorShouldBe(gl, gl.NO_ERROR,
       "calling readBuffer with GL_COLOR_ATTACHMENT0 on fbo should succeed.");

   var maxColorAttachments = gl.getParameter(gl.MAX_COLOR_ATTACHMENTS);
   gl.readBuffer(gl.COLOR_ATTACHMENT0 + maxColorAttachments);
   wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION,
       "calling readBuffer with GL_COLOR_ATTACHMENTi that exceeds MAX_COLOR_ATTACHMENT on fbo should generate INVALID_OPERATION.");
   gl.readBuffer(gl.COLOR_ATTACHMENT1);
   wtu.glErrorShouldBe(gl, gl.NO_ERROR,
       "calling readBuffer with GL_COLOR_ATTACHMENT1 on the fbo should succeed.");
   shouldBe('gl.getParameter(gl.READ_BUFFER)', 'gl.COLOR_ATTACHMENT1');
 }

 debug("");
 debug("Canvas.getContext");

 var wtu = WebGLTestUtils;
 var canvas = document.getElementById("canvas");
 var gl = wtu.create3DContext(canvas, undefined, 2);
 if (!gl) {
   testFailed("context does not exist");
 } else {
   testPassed("context exists");

   debug("");
   debug("Checking reading from framebuffer.");

   // Test on the default framebuffer. Read buffer is GL_BACK by default.
   var backColor = [0, 0, 0, 255];
   clearDrawingbuffer(backColor);
   validateReadingFromFramebuffer(backColor, gl.NO_ERROR,
       "should be no errors when reading from GL_BACK on the default framebuffer.");

   shouldBe('gl.getParameter(gl.READ_BUFFER)', 'gl.BACK');
   testReadBufferOnDefaultFB();

   // Test on fbo. Read buffer is GL_COLOR_ATTACHMENT0 by default
   var fb = gl.createFramebuffer();
   gl.bindFramebuffer(gl.FRAMEBUFFER, fb);
   var colorbuffer = setupRenderbuffer(gl.COLOR_ATTACHMENT0);
   var red = [255, 0, 0, 255];
   clearDrawingbuffer(red);
   validateReadingFromFramebuffer(red, gl.NO_ERROR,
       "should be no errors when reading from GL_COLOR_ATTACHMENT0 on fbo.");

   shouldBe('gl.getParameter(gl.READ_BUFFER)', 'gl.COLOR_ATTACHMENT0');
   testReadBufferOnFBO();

   // Test on user defined read buffer (GL_COLOR_ATTACHMENT1) with or without corresponding image on fbo.
   gl.bindFramebuffer(gl.FRAMEBUFFER, fb);
   var colorbuffer1 = setupRenderbuffer(gl.COLOR_ATTACHMENT1);
   var green = [0, 255, 0, 255];
   gl.drawBuffers([gl.NONE, gl.COLOR_ATTACHMENT1]);
   clearDrawingbuffer(green);
   wtu.glErrorShouldBe(gl, gl.NO_ERROR, "should be no error after setup and clear render buffer");
   gl.readBuffer(gl.COLOR_ATTACHMENT1);
   validateReadingFromFramebuffer(green, gl.NO_ERROR,
       "should be no errors when reading from GL_COLOR_ATTACHMENT1 on fbo.");
   shouldBe('gl.getParameter(gl.READ_BUFFER)', 'gl.COLOR_ATTACHMENT1');
   // Need to reset draw buffers, otherwise it triggers a mac driver bug.
   // We add a separate test for that bug: conformance2/rendering/framebuffer-completeness-unaffected.html
   gl.drawBuffers([gl.COLOR_ATTACHMENT0]);

   gl.framebufferRenderbuffer(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT1, gl.RENDERBUFFER, null)
   gl.readBuffer(gl.COLOR_ATTACHMENT1);
   validateReadingFromFramebuffer(null, gl.INVALID_OPERATION,
       "should generate INVALID_OPERATION when reading from GL_COLOR_ATTACHMENT1 but this attachment has no image currently.");

   // switch to another fbo, read buffer is GL_COLOR_ATTACHMENT0, not GL_COLOR_ATTACHMENT1
   var fb1 = gl.createFramebuffer();
   gl.bindFramebuffer(gl.FRAMEBUFFER, fb1);
   var buffer = setupRenderbuffer(gl.COLOR_ATTACHMENT0);
   shouldBe('gl.getParameter(gl.READ_BUFFER)', 'gl.COLOR_ATTACHMENT0');
   var blue = [0, 0, 255, 255];
   clearDrawingbuffer(blue);
   validateReadingFromFramebuffer(blue, gl.NO_ERROR,
       "should be no errors when reading from GL_COLOR_ATTACHMENT0 on another fbo.");

   // switch from fbo to default fb, read buffer will switch to GL_BACK from GL_COLOR_ATTACHMENT0
   gl.bindFramebuffer(gl.FRAMEBUFFER, null);
   shouldBe('gl.getParameter(gl.READ_BUFFER)', 'gl.BACK');
   validateReadingFromFramebuffer(backColor, gl.NO_ERROR,
       "should be no errors when reading from GL_BACK on the default framebuffer.");

   gl.deleteFramebuffer(fb);
   gl.deleteRenderbuffer(colorbuffer);
   gl.deleteRenderbuffer(colorbuffer1);
   gl.deleteFramebuffer(fb1);
   gl.deleteRenderbuffer(buffer);
 }

 debug("");
 var successfullyParsed = true;

 </script>
 <script src="../../js/js-test-post.js"></script>

 </body>
 </html>
	<!--
	Copyright (c) 2019 The Khronos Group Inc.
	Use of this source code is governed by an MIT-style license that can be
	found in the LICENSE.txt file.
	-->

	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="utf-8">
	<title>Test readBuffer Against WebGL 2</title>
	<link rel="stylesheet" href="../../resources/js-test-style.css"/>
	<script src="../../js/js-test-pre.js"></script>
	<script src="../../js/webgl-test-utils.js"></script>
	</head>
	<body>
	<div id="description"></div>
	<div id="console"></div>
	<canvas id="canvas" width="20" height="20"> </canvas>
	<script>
	"use strict";
	description("This tests reading from fbo");

	var clearDrawingbuffer = function(color) {
	gl.clearColor(color[0] / 255, color[1] / 255, color[2] / 255, color[3] / 255);
	gl.clear(gl.COLOR_BUFFER_BIT);
	}

	var validateReadingFromFramebuffer = function(color, expected, msg) {
	var pixels = new Uint8Array(1 * 1 * 4);
	gl.readPixels(0, 0, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, pixels);
	wtu.glErrorShouldBe(gl, expected, msg);
	if (expected == gl.NO_ERROR)
	wtu.checkCanvasRect(gl, 0, 0, canvas.width, canvas.height, color,
	"the color should be [" + color + "]");
	}

	var setupRenderbuffer = function(attachment) {
	var renderbuffer = gl.createRenderbuffer();
	gl.bindRenderbuffer(gl.RENDERBUFFER, renderbuffer);
	gl.framebufferRenderbuffer(gl.FRAMEBUFFER, attachment, gl.RENDERBUFFER, renderbuffer);
	gl.renderbufferStorage(gl.RENDERBUFFER, gl.RGBA8, canvas.width, canvas.height);
	return renderbuffer;
	}

	var testReadBufferOnDefaultFB = function() {
	gl.readBuffer(gl.NONE);
	wtu.glErrorShouldBe(gl, gl.NO_ERROR,
	"calling readBuffer with GL_NONE on the default framebuffer should succeed.");
	var pixels = new Uint8Array(1 * 1 * 4);
	gl.readPixels(0, 0, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, pixels);
	wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION,
	"should generate INVALID_OPERATION when reading from framebuffer and read buffer is GL_NONE.");
	gl.readBuffer(gl.BACK);
	wtu.glErrorShouldBe(gl, gl.NO_ERROR,
	"calling readBuffer with GL_BACK on the default framebuffer should succeed.");

	gl.readBuffer(gl.COLOR_ATTACHMENT0);
	wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION,
	"calling readBuffer with GL_COLOR_ATTACHMENT0 on the default framebuffer should generate INVALID_OPERATION.");
	}

	var testReadBufferOnFBO = function() {
	gl.readBuffer(gl.BACK);
	wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION,
	"calling readBuffer with GL_BACK on fbo should generate INVALID_OPERATION.");

	gl.readBuffer(gl.NONE);
	wtu.glErrorShouldBe(gl, gl.NO_ERROR,
	"calling readBuffer with GL_NONE on fbo should succeed.");
	var pixels = new Uint8Array(1 * 1 * 4);
	gl.readPixels(0, 0, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, pixels);
	wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION,
	"should generate INVALID_OPERATION when reading from framebuffer and read buffer is GL_NONE.");
	gl.readBuffer(gl.COLOR_ATTACHMENT0);
	wtu.glErrorShouldBe(gl, gl.NO_ERROR,
	"calling readBuffer with GL_COLOR_ATTACHMENT0 on fbo should succeed.");

	var maxColorAttachments = gl.getParameter(gl.MAX_COLOR_ATTACHMENTS);
	gl.readBuffer(gl.COLOR_ATTACHMENT0 + maxColorAttachments);
	wtu.glErrorShouldBe(gl, gl.INVALID_OPERATION,
	"calling readBuffer with GL_COLOR_ATTACHMENTi that exceeds MAX_COLOR_ATTACHMENT on fbo should generate INVALID_OPERATION.");
	gl.readBuffer(gl.COLOR_ATTACHMENT1);
	wtu.glErrorShouldBe(gl, gl.NO_ERROR,
	"calling readBuffer with GL_COLOR_ATTACHMENT1 on the fbo should succeed.");
	shouldBe('gl.getParameter(gl.READ_BUFFER)', 'gl.COLOR_ATTACHMENT1');
	}

	debug("");
	debug("Canvas.getContext");

	var wtu = WebGLTestUtils;
	var canvas = document.getElementById("canvas");
	var gl = wtu.create3DContext(canvas, undefined, 2);
	if (!gl) {
	testFailed("context does not exist");
	} else {
	testPassed("context exists");

	debug("");
	debug("Checking reading from framebuffer.");

	// Test on the default framebuffer. Read buffer is GL_BACK by default.
	var backColor = [0, 0, 0, 255];
	clearDrawingbuffer(backColor);
	validateReadingFromFramebuffer(backColor, gl.NO_ERROR,
	"should be no errors when reading from GL_BACK on the default framebuffer.");

	shouldBe('gl.getParameter(gl.READ_BUFFER)', 'gl.BACK');
	testReadBufferOnDefaultFB();

	// Test on fbo. Read buffer is GL_COLOR_ATTACHMENT0 by default
	var fb = gl.createFramebuffer();
	gl.bindFramebuffer(gl.FRAMEBUFFER, fb);
	var colorbuffer = setupRenderbuffer(gl.COLOR_ATTACHMENT0);
	var red = [255, 0, 0, 255];
	clearDrawingbuffer(red);
	validateReadingFromFramebuffer(red, gl.NO_ERROR,
	"should be no errors when reading from GL_COLOR_ATTACHMENT0 on fbo.");

	shouldBe('gl.getParameter(gl.READ_BUFFER)', 'gl.COLOR_ATTACHMENT0');
	testReadBufferOnFBO();

	// Test on user defined read buffer (GL_COLOR_ATTACHMENT1) with or without corresponding image on fbo.
	gl.bindFramebuffer(gl.FRAMEBUFFER, fb);
	var colorbuffer1 = setupRenderbuffer(gl.COLOR_ATTACHMENT1);
	var green = [0, 255, 0, 255];
	gl.drawBuffers([gl.NONE, gl.COLOR_ATTACHMENT1]);
	clearDrawingbuffer(green);
	wtu.glErrorShouldBe(gl, gl.NO_ERROR, "should be no error after setup and clear render buffer");
	gl.readBuffer(gl.COLOR_ATTACHMENT1);
	validateReadingFromFramebuffer(green, gl.NO_ERROR,
	"should be no errors when reading from GL_COLOR_ATTACHMENT1 on fbo.");
	shouldBe('gl.getParameter(gl.READ_BUFFER)', 'gl.COLOR_ATTACHMENT1');
	// Need to reset draw buffers, otherwise it triggers a mac driver bug.
	// We add a separate test for that bug: conformance2/rendering/framebuffer-completeness-unaffected.html
	gl.drawBuffers([gl.COLOR_ATTACHMENT0]);

	gl.framebufferRenderbuffer(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT1, gl.RENDERBUFFER, null)
	gl.readBuffer(gl.COLOR_ATTACHMENT1);
	validateReadingFromFramebuffer(null, gl.INVALID_OPERATION,
	"should generate INVALID_OPERATION when reading from GL_COLOR_ATTACHMENT1 but this attachment has no image currently.");

	// switch to another fbo, read buffer is GL_COLOR_ATTACHMENT0, not GL_COLOR_ATTACHMENT1
	var fb1 = gl.createFramebuffer();
	gl.bindFramebuffer(gl.FRAMEBUFFER, fb1);
	var buffer = setupRenderbuffer(gl.COLOR_ATTACHMENT0);
	shouldBe('gl.getParameter(gl.READ_BUFFER)', 'gl.COLOR_ATTACHMENT0');
	var blue = [0, 0, 255, 255];
	clearDrawingbuffer(blue);
	validateReadingFromFramebuffer(blue, gl.NO_ERROR,
	"should be no errors when reading from GL_COLOR_ATTACHMENT0 on another fbo.");

	// switch from fbo to default fb, read buffer will switch to GL_BACK from GL_COLOR_ATTACHMENT0
	gl.bindFramebuffer(gl.FRAMEBUFFER, null);
	shouldBe('gl.getParameter(gl.READ_BUFFER)', 'gl.BACK');
	validateReadingFromFramebuffer(backColor, gl.NO_ERROR,
	"should be no errors when reading from GL_BACK on the default framebuffer.");

	gl.deleteFramebuffer(fb);
	gl.deleteRenderbuffer(colorbuffer);
	gl.deleteRenderbuffer(colorbuffer1);
	gl.deleteFramebuffer(fb1);
	gl.deleteRenderbuffer(buffer);
	}

	debug("");
	var successfullyParsed = true;

	</script>
	<script src="../../js/js-test-post.js"></script>

	</body>
	</html>