LayoutTests/webgl/1.0.2/resources/webgl_test_files/conformance/context/context-attributes-alpha-depth-stencil-antialias.html - WebKit - Git at Google

 <!--

 /*
 ** Copyright (c) 2012 The Khronos Group Inc.
 **
 ** Permission is hereby granted, free of charge, to any person obtaining a
 ** copy of this software and/or associated documentation files (the
 ** "Materials"), to deal in the Materials without restriction, including
 ** without limitation the rights to use, copy, modify, merge, publish,
 ** distribute, sublicense, and/or sell copies of the Materials, and to
 ** permit persons to whom the Materials are furnished to do so, subject to
 ** the following conditions:
 **
 ** The above copyright notice and this permission notice shall be included
 ** in all copies or substantial portions of the Materials.
 **
 ** THE MATERIALS ARE PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 ** EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 ** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 ** IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 ** CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 ** TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 ** MATERIALS OR THE USE OR OTHER DEALINGS IN THE MATERIALS.
 */

 -->

 <!DOCTYPE html>
 <html>
 <head>
 <meta charset="utf-8">
 <link rel="stylesheet" href="../../resources/js-test-style.css"/>
 <script src="../../resources/js-test-pre.js"></script>
 <script src="../resources/webgl-test.js"></script>
 <script src="../resources/webgl-test-utils.js"></script>
 <script id="vshader" type="x-shader/x-vertex">
 attribute vec3 pos;
 attribute vec4 colorIn;
 varying vec4 color;

 void main()
 {
     color = colorIn;
     gl_Position = vec4(pos.xyz, 1.0);
 }
 </script>

 <script id="fshader" type="x-shader/x-fragment">
 precision mediump float;

 varying vec4 color;

 void main()
 {
     gl_FragColor = color;
 }
 </script>

 <script>
 "use strict";

 // These four declarations need to be global for "shouldBe" to see them
 var wtu = WebGLTestUtils;
 var gl;
 var contextAttribs = null;
 var pixel = [0, 0, 0, 1];
 var correctColor = null;
 var framebuffer;
 var fbHasColor;
 var fbHasDepth;
 var fbHasStencil;

 function init()
 {
     initTestingHarnessWaitUntilDone();

     description('Verify WebGLContextAttributes are working as specified, including alpha, depth, stencil, antialias, but not premultipliedAlpha');

     runTest();
 }

 function getWebGL(canvasWidth, canvasHeight, contextAttribs, clearColor, clearDepth, clearStencil)
 {
     var canvas = document.createElement("canvas");
     if (!canvas)
         return null;
     canvas.width = canvasWidth;
     canvas.height = canvasHeight;

     gl = wtu.create3DContext(canvas, contextAttribs);
     if (!gl)
         return null;

     var program = wtu.setupProgram(gl, ["vshader", "fshader"], ["pos", "colorIn"]);
     if (!program)
         return null;

     gl.enable(gl.DEPTH_TEST);
     gl.enable(gl.STENCIL_TEST);

     gl.clearColor(clearColor[0], clearColor[1], clearColor[2], clearColor[3]);
     gl.clearDepth(clearDepth);
     gl.clearStencil(clearStencil);
     gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT | gl.STENCIL_BUFFER_BIT);

     framebuffer = gl.createFramebuffer();
     gl.bindFramebuffer(gl.FRAMEBUFFER, framebuffer);
     var texture = gl.createTexture();
     gl.bindTexture(gl.TEXTURE_2D, texture);
     gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.canvas.width, gl.canvas.height, 0, gl.RGBA, gl.UNSIGNED_BYTE, null);
     gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, texture, 0);
     fbHasStencil = false;
     fbHasDepth = false;
     fbHasColor = gl.checkFramebufferStatus(gl.FRAMEBUFFER) == gl.FRAMEBUFFER_COMPLETE;
     if (fbHasColor) {
       var depthStencil = gl.createRenderbuffer();
       gl.bindRenderbuffer(gl.RENDERBUFFER, depthStencil);
       gl.renderbufferStorage(gl.RENDERBUFFER, gl.DEPTH_STENCIL, gl.canvas.width, gl.canvas.height);
       gl.framebufferRenderbuffer(gl.FRAMEBUFFER, gl.DEPTH_STENCIL_ATTACHMENT, gl.RENDERBUFFER, depthStencil);
       fbHasDepth = gl.checkFramebufferStatus(gl.FRAMEBUFFER) == gl.FRAMEBUFFER_COMPLETE;
       if (!fbHasDepth) {
         gl.framebufferRenderbuffer(gl.FRAMEBUFFER, gl.DEPTH_STENCIL_ATTACHMENT, gl.RENDERBUFFER, null);
         shouldBe('gl.checkFramebufferStatus(gl.FRAMEBUFFER)', 'gl.FRAMEBUFFER_COMPLETE');
       } else {
         fbHasStencil = true;
       }
     }
     gl.bindFramebuffer(gl.FRAMEBUFFER, null);
     glErrorShouldBe(gl, gl.NO_ERROR, "should be no errors");

     return gl;
 }

 function drawAndReadPixel(gl, vertices, colors)
 {
     var colorOffset = vertices.byteLength;

     var vbo = gl.createBuffer();
     gl.bindBuffer(gl.ARRAY_BUFFER, vbo);
     gl.bufferData(gl.ARRAY_BUFFER, colorOffset + colors.byteLength, gl.STATIC_DRAW);
     gl.bufferSubData(gl.ARRAY_BUFFER, 0, vertices);
     gl.bufferSubData(gl.ARRAY_BUFFER, colorOffset, colors);

     gl.vertexAttribPointer(0, 3, gl.FLOAT, false, 0, 0);
     gl.enableVertexAttribArray(0);
     gl.vertexAttribPointer(1, 4, gl.UNSIGNED_BYTE, true, 0, colorOffset);
     gl.enableVertexAttribArray(1);

     gl.drawArrays(gl.TRIANGLES, 0, vertices.length / 3);
 }

 function testAlpha(alpha)
 {
     debug("Testing alpha = " + alpha);
     if (alpha) {
         shouldBeNonNull("gl = getWebGL(1, 1, { alpha: true, depth: false, stencil: false, antialias: false }, [ 0, 0, 0, 0 ], 1, 0)");
         shouldBeTrue("gl.getParameter(gl.ALPHA_BITS) >= 8");
     } else {
         shouldBeNonNull("gl = getWebGL(1, 1, { alpha: false, depth: false, stencil: false, antialias: false }, [ 0, 0, 0, 0 ], 1, 0)");
         shouldBeTrue("gl.getParameter(gl.ALPHA_BITS) == 0");
     }
     shouldBeTrue("gl.getParameter(gl.RED_BITS) >= 8");
     shouldBeTrue("gl.getParameter(gl.GREEN_BITS) >= 8");
     shouldBeTrue("gl.getParameter(gl.BLUE_BITS) >= 8");
     shouldBeTrue("gl.getParameter(gl.DEPTH_BITS) == 0");
     shouldBeTrue("gl.getParameter(gl.STENCIL_BITS) == 0");

     shouldBeNonNull("contextAttribs = gl.getContextAttributes()");
     shouldBeTrue("contextAttribs.alpha == " + alpha);

     var correctColor = (contextAttribs.alpha ? [0, 0, 0, 0] : [0, 0, 0, 255]);
     wtu.checkCanvasRect(gl, 0, 0, 1, 1, correctColor);

     if (fbHasColor) {
       gl.bindFramebuffer(gl.FRAMEBUFFER, framebuffer);
       gl.clearColor(0.5, 0.5, 0.5, 0.5);
       gl.clear(gl.COLOR_BUFFER_BIT);
       wtu.checkCanvasRect(gl, 0, 0, 1, 1, [127, 127, 127, 127], undefined, 1);
       gl.bindFramebuffer(gl.FRAMEBUFFER, null);
     }
 }

 function testDepth(depth)
 {
     debug("Testing depth = " + depth);
     if (depth) {
         shouldBeNonNull("gl = getWebGL(1, 1, { stencil: false, antialias: false }, [ 0, 0, 0, 1 ], 1, 0)");
         shouldBeTrue("gl.getParameter(gl.DEPTH_BITS) >= 16");
     } else {
         shouldBeNonNull("gl = getWebGL(1, 1, { depth: false, stencil: false, antialias: false }, [ 0, 0, 0, 1 ], 1, 0)");
         shouldBeTrue("gl.getParameter(gl.DEPTH_BITS) == 0");
     }
     shouldBeTrue("gl.getParameter(gl.RED_BITS) >= 8");
     shouldBeTrue("gl.getParameter(gl.GREEN_BITS) >= 8");
     shouldBeTrue("gl.getParameter(gl.BLUE_BITS) >= 8");
     shouldBeTrue("gl.getParameter(gl.ALPHA_BITS) >= 8");

     shouldBeNonNull("contextAttribs = gl.getContextAttributes()");

     gl.depthFunc(gl.NEVER);

     var vertices = new Float32Array([
          1.0,  1.0, 0.0,
         -1.0,  1.0, 0.0,
         -1.0, -1.0, 0.0,
          1.0,  1.0, 0.0,
         -1.0, -1.0, 0.0,
          1.0, -1.0, 0.0]);
     var colors = new Uint8Array([
         255, 0, 0, 255,
         255, 0, 0, 255,
         255, 0, 0, 255,
         255, 0, 0, 255,
         255, 0, 0, 255,
         255, 0, 0, 255]);

     drawAndReadPixel(gl, vertices, colors, 0, 0);
     correctColor = (contextAttribs.depth ? [0, 0, 0, 255] : [255, 0, 0, 255]);
     wtu.checkCanvasRect(gl, 0, 0, 1, 1, correctColor);

     if (fbHasDepth) {
       gl.bindFramebuffer(gl.FRAMEBUFFER, framebuffer);
       gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
       drawAndReadPixel(gl, vertices, colors, 0, 0);
       wtu.checkCanvasRect(gl, 0, 0, 1, 1, [0, 0, 0, 255]);
       gl.bindFramebuffer(gl.FRAMEBUFFER, null);
     }
 }

 function testStencilAndDepth(stencil, depth)
 {
     debug("Testing stencil = " + stencil + ", depth = " + depth);
     var creationString =
         "gl = getWebGL(1, 1, { depth: " + depth + ", stencil: " + stencil + ", antialias: false }, [ 0, 0, 0, 1 ], 1, 0)";
     shouldBeNonNull(creationString);

     shouldBeTrue("gl.getParameter(gl.RED_BITS) >= 8");
     shouldBeTrue("gl.getParameter(gl.GREEN_BITS) >= 8");
     shouldBeTrue("gl.getParameter(gl.BLUE_BITS) >= 8");
     shouldBeTrue("gl.getParameter(gl.ALPHA_BITS) >= 8");
     if (depth)
         shouldBeTrue("gl.getParameter(gl.DEPTH_BITS) >= 16");
     else
         shouldBeTrue("gl.getParameter(gl.DEPTH_BITS) == 0");

     if (stencil)
         shouldBeTrue("gl.getParameter(gl.STENCIL_BITS) >= 8");
     else
         shouldBeTrue("gl.getParameter(gl.STENCIL_BITS) == 0");

     shouldBeNonNull("contextAttribs = gl.getContextAttributes()");
     if (!depth && contextAttribs.depth) {
         testFailed("WebGL implementation provided a depth buffer when it should not have");
     }
     if (!contextAttribs.depth)
         depth = false;
     if (!stencil && contextAttribs.stencil) {
         testFailed("WebGL implementation provided a stencil buffer when it should not have");
     }
     if (!contextAttribs.stencil)
         stencil = false;

     gl.depthFunc(gl.ALWAYS);

     gl.stencilFunc(gl.NEVER, 1, 1);
     gl.stencilOp(gl.KEEP, gl.KEEP, gl.KEEP);

     var vertices = new Float32Array([
          1.0, 1.0, 0.0,
         -1.0, 1.0, 0.0,
         -1.0, -1.0, 0.0,
          1.0, 1.0, 0.0,
         -1.0, -1.0, 0.0,
          1.0, -1.0, 0.0]);
     var colors = new Uint8Array([
         255, 0, 0, 255,
         255, 0, 0, 255,
         255, 0, 0, 255,
         255, 0, 0, 255,
         255, 0, 0, 255,
         255, 0, 0, 255]);

     drawAndReadPixel(gl, vertices, colors, 0, 0);
     correctColor = (stencil ? [0, 0, 0, 255] : [255, 0, 0, 255]);
     wtu.checkCanvasRect(gl, 0, 0, 1, 1, correctColor)

     if (fbHasStencil) {
       gl.bindFramebuffer(gl.FRAMEBUFFER, framebuffer);
       gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
       drawAndReadPixel(gl, vertices, colors, 0, 0);
       wtu.checkCanvasRect(gl, 0, 0, 1, 1, [0, 0, 0, 255]);
       gl.bindFramebuffer(gl.FRAMEBUFFER, null);
     }
 }

 function testAntialias(antialias)
 {
     debug("Testing antialias = " + antialias);
     if (antialias)
         shouldBeNonNull("gl = getWebGL(2, 2, { depth: false, stencil: false, alpha: false, antialias: true }, [ 0, 0, 0, 1 ], 1, 0)");
     else
         shouldBeNonNull("gl = getWebGL(2, 2, { depth: false, stencil: false, alpha: false, antialias: false }, [ 0, 0, 0, 1 ], 1, 0)");
     shouldBeNonNull("contextAttribs = gl.getContextAttributes()");

     var vertices = new Float32Array([
          1.0, 1.0, 0.0,
         -1.0, 1.0, 0.0,
         -1.0, -1.0, 0.0]);
     var colors = new Uint8Array([
         255, 0, 0, 255,
         255, 0, 0, 255,
         255, 0, 0, 255]);
     drawAndReadPixel(gl, vertices, colors, 0, 0);
     var buf = new Uint8Array(1 * 1 * 4);
     gl.readPixels(0, 0, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, buf);
     pixel[0] = buf[0];
     shouldBe("pixel[0] != 255 && pixel[0] != 0", "contextAttribs.antialias");
 }

 function runTest()
 {

     testAlpha(true);
     testAlpha(false);
     testDepth(true);
     testDepth(false);
     testStencilAndDepth(true, false);
     testStencilAndDepth(false, false);
     testStencilAndDepth(true, true);
     testStencilAndDepth(false, true);
     testAntialias(true);
     testAntialias(false);

     finishTest();
 }

 </script>
 </head>
 <body onload="init()">
 <div id="description"></div>
 <div id="console"></div>
 </body>
 </html>
	<!--

	/*
	** Copyright (c) 2012 The Khronos Group Inc.
	**
	** Permission is hereby granted, free of charge, to any person obtaining a
	** copy of this software and/or associated documentation files (the
	** "Materials"), to deal in the Materials without restriction, including
	** without limitation the rights to use, copy, modify, merge, publish,
	** distribute, sublicense, and/or sell copies of the Materials, and to
	** permit persons to whom the Materials are furnished to do so, subject to
	** the following conditions:
	**
	** The above copyright notice and this permission notice shall be included
	** in all copies or substantial portions of the Materials.
	**
	** THE MATERIALS ARE PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	** EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
	** IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
	** CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
	** TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
	** MATERIALS OR THE USE OR OTHER DEALINGS IN THE MATERIALS.
	*/

	-->

	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="utf-8">
	<link rel="stylesheet" href="../../resources/js-test-style.css"/>
	<script src="../../resources/js-test-pre.js"></script>
	<script src="../resources/webgl-test.js"></script>
	<script src="../resources/webgl-test-utils.js"></script>
	<script id="vshader" type="x-shader/x-vertex">
	attribute vec3 pos;
	attribute vec4 colorIn;
	varying vec4 color;

	void main()
	{
	color = colorIn;
	gl_Position = vec4(pos.xyz, 1.0);
	}
	</script>

	<script id="fshader" type="x-shader/x-fragment">
	precision mediump float;

	varying vec4 color;

	void main()
	{
	gl_FragColor = color;
	}
	</script>

	<script>
	"use strict";

	// These four declarations need to be global for "shouldBe" to see them
	var wtu = WebGLTestUtils;
	var gl;
	var contextAttribs = null;
	var pixel = [0, 0, 0, 1];
	var correctColor = null;
	var framebuffer;
	var fbHasColor;
	var fbHasDepth;
	var fbHasStencil;

	function init()
	{
	initTestingHarnessWaitUntilDone();

	description('Verify WebGLContextAttributes are working as specified, including alpha, depth, stencil, antialias, but not premultipliedAlpha');

	runTest();
	}

	function getWebGL(canvasWidth, canvasHeight, contextAttribs, clearColor, clearDepth, clearStencil)
	{
	var canvas = document.createElement("canvas");
	if (!canvas)
	return null;
	canvas.width = canvasWidth;
	canvas.height = canvasHeight;

	gl = wtu.create3DContext(canvas, contextAttribs);
	if (!gl)
	return null;

	var program = wtu.setupProgram(gl, ["vshader", "fshader"], ["pos", "colorIn"]);
	if (!program)
	return null;

	gl.enable(gl.DEPTH_TEST);
	gl.enable(gl.STENCIL_TEST);

	gl.clearColor(clearColor[0], clearColor[1], clearColor[2], clearColor[3]);
	gl.clearDepth(clearDepth);
	gl.clearStencil(clearStencil);
	gl.clear(gl.COLOR_BUFFER_BIT \| gl.DEPTH_BUFFER_BIT \| gl.STENCIL_BUFFER_BIT);

	framebuffer = gl.createFramebuffer();
	gl.bindFramebuffer(gl.FRAMEBUFFER, framebuffer);
	var texture = gl.createTexture();
	gl.bindTexture(gl.TEXTURE_2D, texture);
	gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.canvas.width, gl.canvas.height, 0, gl.RGBA, gl.UNSIGNED_BYTE, null);
	gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, texture, 0);
	fbHasStencil = false;
	fbHasDepth = false;
	fbHasColor = gl.checkFramebufferStatus(gl.FRAMEBUFFER) == gl.FRAMEBUFFER_COMPLETE;
	if (fbHasColor) {
	var depthStencil = gl.createRenderbuffer();
	gl.bindRenderbuffer(gl.RENDERBUFFER, depthStencil);
	gl.renderbufferStorage(gl.RENDERBUFFER, gl.DEPTH_STENCIL, gl.canvas.width, gl.canvas.height);
	gl.framebufferRenderbuffer(gl.FRAMEBUFFER, gl.DEPTH_STENCIL_ATTACHMENT, gl.RENDERBUFFER, depthStencil);
	fbHasDepth = gl.checkFramebufferStatus(gl.FRAMEBUFFER) == gl.FRAMEBUFFER_COMPLETE;
	if (!fbHasDepth) {
	gl.framebufferRenderbuffer(gl.FRAMEBUFFER, gl.DEPTH_STENCIL_ATTACHMENT, gl.RENDERBUFFER, null);
	shouldBe('gl.checkFramebufferStatus(gl.FRAMEBUFFER)', 'gl.FRAMEBUFFER_COMPLETE');
	} else {
	fbHasStencil = true;
	}
	}
	gl.bindFramebuffer(gl.FRAMEBUFFER, null);
	glErrorShouldBe(gl, gl.NO_ERROR, "should be no errors");

	return gl;
	}

	function drawAndReadPixel(gl, vertices, colors)
	{
	var colorOffset = vertices.byteLength;

	var vbo = gl.createBuffer();
	gl.bindBuffer(gl.ARRAY_BUFFER, vbo);
	gl.bufferData(gl.ARRAY_BUFFER, colorOffset + colors.byteLength, gl.STATIC_DRAW);
	gl.bufferSubData(gl.ARRAY_BUFFER, 0, vertices);
	gl.bufferSubData(gl.ARRAY_BUFFER, colorOffset, colors);

	gl.vertexAttribPointer(0, 3, gl.FLOAT, false, 0, 0);
	gl.enableVertexAttribArray(0);
	gl.vertexAttribPointer(1, 4, gl.UNSIGNED_BYTE, true, 0, colorOffset);
	gl.enableVertexAttribArray(1);

	gl.drawArrays(gl.TRIANGLES, 0, vertices.length / 3);
	}

	function testAlpha(alpha)
	{
	debug("Testing alpha = " + alpha);
	if (alpha) {
	shouldBeNonNull("gl = getWebGL(1, 1, { alpha: true, depth: false, stencil: false, antialias: false }, [ 0, 0, 0, 0 ], 1, 0)");
	shouldBeTrue("gl.getParameter(gl.ALPHA_BITS) >= 8");
	} else {
	shouldBeNonNull("gl = getWebGL(1, 1, { alpha: false, depth: false, stencil: false, antialias: false }, [ 0, 0, 0, 0 ], 1, 0)");
	shouldBeTrue("gl.getParameter(gl.ALPHA_BITS) == 0");
	}
	shouldBeTrue("gl.getParameter(gl.RED_BITS) >= 8");
	shouldBeTrue("gl.getParameter(gl.GREEN_BITS) >= 8");
	shouldBeTrue("gl.getParameter(gl.BLUE_BITS) >= 8");
	shouldBeTrue("gl.getParameter(gl.DEPTH_BITS) == 0");
	shouldBeTrue("gl.getParameter(gl.STENCIL_BITS) == 0");

	shouldBeNonNull("contextAttribs = gl.getContextAttributes()");
	shouldBeTrue("contextAttribs.alpha == " + alpha);

	var correctColor = (contextAttribs.alpha ? [0, 0, 0, 0] : [0, 0, 0, 255]);
	wtu.checkCanvasRect(gl, 0, 0, 1, 1, correctColor);

	if (fbHasColor) {
	gl.bindFramebuffer(gl.FRAMEBUFFER, framebuffer);
	gl.clearColor(0.5, 0.5, 0.5, 0.5);
	gl.clear(gl.COLOR_BUFFER_BIT);
	wtu.checkCanvasRect(gl, 0, 0, 1, 1, [127, 127, 127, 127], undefined, 1);
	gl.bindFramebuffer(gl.FRAMEBUFFER, null);
	}
	}

	function testDepth(depth)
	{
	debug("Testing depth = " + depth);
	if (depth) {
	shouldBeNonNull("gl = getWebGL(1, 1, { stencil: false, antialias: false }, [ 0, 0, 0, 1 ], 1, 0)");
	shouldBeTrue("gl.getParameter(gl.DEPTH_BITS) >= 16");
	} else {
	shouldBeNonNull("gl = getWebGL(1, 1, { depth: false, stencil: false, antialias: false }, [ 0, 0, 0, 1 ], 1, 0)");
	shouldBeTrue("gl.getParameter(gl.DEPTH_BITS) == 0");
	}
	shouldBeTrue("gl.getParameter(gl.RED_BITS) >= 8");
	shouldBeTrue("gl.getParameter(gl.GREEN_BITS) >= 8");
	shouldBeTrue("gl.getParameter(gl.BLUE_BITS) >= 8");
	shouldBeTrue("gl.getParameter(gl.ALPHA_BITS) >= 8");

	shouldBeNonNull("contextAttribs = gl.getContextAttributes()");

	gl.depthFunc(gl.NEVER);

	var vertices = new Float32Array([
	1.0, 1.0, 0.0,
	-1.0, 1.0, 0.0,
	-1.0, -1.0, 0.0,
	1.0, 1.0, 0.0,
	-1.0, -1.0, 0.0,
	1.0, -1.0, 0.0]);
	var colors = new Uint8Array([
	255, 0, 0, 255,
	255, 0, 0, 255,
	255, 0, 0, 255,
	255, 0, 0, 255,
	255, 0, 0, 255,
	255, 0, 0, 255]);

	drawAndReadPixel(gl, vertices, colors, 0, 0);
	correctColor = (contextAttribs.depth ? [0, 0, 0, 255] : [255, 0, 0, 255]);
	wtu.checkCanvasRect(gl, 0, 0, 1, 1, correctColor);

	if (fbHasDepth) {
	gl.bindFramebuffer(gl.FRAMEBUFFER, framebuffer);
	gl.clear(gl.COLOR_BUFFER_BIT \| gl.DEPTH_BUFFER_BIT);
	drawAndReadPixel(gl, vertices, colors, 0, 0);
	wtu.checkCanvasRect(gl, 0, 0, 1, 1, [0, 0, 0, 255]);
	gl.bindFramebuffer(gl.FRAMEBUFFER, null);
	}
	}

	function testStencilAndDepth(stencil, depth)
	{
	debug("Testing stencil = " + stencil + ", depth = " + depth);
	var creationString =
	"gl = getWebGL(1, 1, { depth: " + depth + ", stencil: " + stencil + ", antialias: false }, [ 0, 0, 0, 1 ], 1, 0)";
	shouldBeNonNull(creationString);

	shouldBeTrue("gl.getParameter(gl.RED_BITS) >= 8");
	shouldBeTrue("gl.getParameter(gl.GREEN_BITS) >= 8");
	shouldBeTrue("gl.getParameter(gl.BLUE_BITS) >= 8");
	shouldBeTrue("gl.getParameter(gl.ALPHA_BITS) >= 8");
	if (depth)
	shouldBeTrue("gl.getParameter(gl.DEPTH_BITS) >= 16");
	else
	shouldBeTrue("gl.getParameter(gl.DEPTH_BITS) == 0");

	if (stencil)
	shouldBeTrue("gl.getParameter(gl.STENCIL_BITS) >= 8");
	else
	shouldBeTrue("gl.getParameter(gl.STENCIL_BITS) == 0");

	shouldBeNonNull("contextAttribs = gl.getContextAttributes()");
	if (!depth && contextAttribs.depth) {
	testFailed("WebGL implementation provided a depth buffer when it should not have");
	}
	if (!contextAttribs.depth)
	depth = false;
	if (!stencil && contextAttribs.stencil) {
	testFailed("WebGL implementation provided a stencil buffer when it should not have");
	}
	if (!contextAttribs.stencil)
	stencil = false;

	gl.depthFunc(gl.ALWAYS);

	gl.stencilFunc(gl.NEVER, 1, 1);
	gl.stencilOp(gl.KEEP, gl.KEEP, gl.KEEP);

	var vertices = new Float32Array([
	1.0, 1.0, 0.0,
	-1.0, 1.0, 0.0,
	-1.0, -1.0, 0.0,
	1.0, 1.0, 0.0,
	-1.0, -1.0, 0.0,
	1.0, -1.0, 0.0]);
	var colors = new Uint8Array([
	255, 0, 0, 255,
	255, 0, 0, 255,
	255, 0, 0, 255,
	255, 0, 0, 255,
	255, 0, 0, 255,
	255, 0, 0, 255]);

	drawAndReadPixel(gl, vertices, colors, 0, 0);
	correctColor = (stencil ? [0, 0, 0, 255] : [255, 0, 0, 255]);
	wtu.checkCanvasRect(gl, 0, 0, 1, 1, correctColor)

	if (fbHasStencil) {
	gl.bindFramebuffer(gl.FRAMEBUFFER, framebuffer);
	gl.clear(gl.COLOR_BUFFER_BIT \| gl.DEPTH_BUFFER_BIT);
	drawAndReadPixel(gl, vertices, colors, 0, 0);
	wtu.checkCanvasRect(gl, 0, 0, 1, 1, [0, 0, 0, 255]);
	gl.bindFramebuffer(gl.FRAMEBUFFER, null);
	}
	}

	function testAntialias(antialias)
	{
	debug("Testing antialias = " + antialias);
	if (antialias)
	shouldBeNonNull("gl = getWebGL(2, 2, { depth: false, stencil: false, alpha: false, antialias: true }, [ 0, 0, 0, 1 ], 1, 0)");
	else
	shouldBeNonNull("gl = getWebGL(2, 2, { depth: false, stencil: false, alpha: false, antialias: false }, [ 0, 0, 0, 1 ], 1, 0)");
	shouldBeNonNull("contextAttribs = gl.getContextAttributes()");

	var vertices = new Float32Array([
	1.0, 1.0, 0.0,
	-1.0, 1.0, 0.0,
	-1.0, -1.0, 0.0]);
	var colors = new Uint8Array([
	255, 0, 0, 255,
	255, 0, 0, 255,
	255, 0, 0, 255]);
	drawAndReadPixel(gl, vertices, colors, 0, 0);
	var buf = new Uint8Array(1 * 1 * 4);
	gl.readPixels(0, 0, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, buf);
	pixel[0] = buf[0];
	shouldBe("pixel[0] != 255 && pixel[0] != 0", "contextAttribs.antialias");
	}

	function runTest()
	{

	testAlpha(true);
	testAlpha(false);
	testDepth(true);
	testDepth(false);
	testStencilAndDepth(true, false);
	testStencilAndDepth(false, false);
	testStencilAndDepth(true, true);
	testStencilAndDepth(false, true);
	testAntialias(true);
	testAntialias(false);

	finishTest();
	}

	</script>
	</head>
	<body onload="init()">
	<div id="description"></div>
	<div id="console"></div>
	</body>
	</html>