LayoutTests/webgl/2.0.0/resources/webgl_test_files/conformance/extensions/oes-texture-float.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">
 <title>WebGL OES_texture_float Conformance Tests</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>
 <canvas id="canvas" style="width: 50px; height: 50px;"> </canvas>
 <div id="console"></div>
 <!-- Shaders for testing floating-point textures -->
 <script id="testFragmentShader" type="x-shader/x-fragment">
 precision mediump float;
 uniform sampler2D tex;
 uniform vec4 subtractor;
 varying vec2 texCoord;
 void main()
 {
     vec4 color = texture2D(tex, texCoord);
     if (abs(color.r - subtractor.r) +
         abs(color.g - subtractor.g) +
         abs(color.b - subtractor.b) +
         abs(color.a - subtractor.a) < 8.0) {
         gl_FragColor = vec4(0.0, 1.0, 0.0, 1.0);
     } else {
         gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
     }
 }
 </script>
 <!-- Shaders for testing floating-point render targets -->
 <script id="positionVertexShader" type="x-shader/x-vertex">
 attribute vec4 vPosition;
 void main()
 {
     gl_Position = vPosition;
 }
 </script>
 <script id="floatingPointFragmentShader" type="x-shader/x-fragment">
 void main()
 {
     gl_FragColor = vec4(10000.0, 10000.0, 10000.0, 10000.0);
 }
 </script>
 <script>
 "use strict";
 description("This test verifies the functionality of the OES_texture_float extension, if it is available.");

 debug("");

 var wtu = WebGLTestUtils;
 var canvas = document.getElementById("canvas");
 var gl = wtu.create3DContext(canvas);

 if (!gl) {
     testFailed("WebGL context does not exist");
 } else {
     testPassed("WebGL context exists");

     var texturedShaders = [
         wtu.simpleTextureVertexShader,
         "testFragmentShader"
     ];
     var testProgram =
         wtu.setupProgram(gl,
                          texturedShaders,
                          ['vPosition', 'texCoord0'],
                          [0, 1]);
     var quadParameters = wtu.setupUnitQuad(gl, 0, 1);

     // First verify that allocation of floating-point textures fails if
     // the extension has not been enabled yet.
     runTextureCreationTest(testProgram, false);

     if (!gl.getExtension("OES_texture_float")) {
         testPassed("No OES_texture_float support -- this is legal");
     } else {
         testPassed("Successfully enabled OES_texture_float extension");
         // If alpha value is missing from a texture it gets filled to 1 when sampling according to GLES2.0 table 3.12
         runTextureCreationTest(testProgram, true, gl.RGBA, 4, [10000, 10000, 10000, 10000]);
         runTextureCreationTest(testProgram, true, gl.RGB, 3, [10000, 10000, 10000, 1]);
         runTextureCreationTest(testProgram, true, gl.LUMINANCE, 1, [10000, 10000, 10000, 1]);
         runTextureCreationTest(testProgram, true, gl.ALPHA, 1, [0, 0, 0, 10000]);
         runTextureCreationTest(testProgram, true, gl.LUMINANCE_ALPHA, 2, [10000, 10000, 10000, 10000]);

         (function() {
             debug("");
             var renderable = isRenderable(gl);
             var renderableExtName = "WEBGL_color_buffer_float";
             var supported = gl.getSupportedExtensions().includes(renderableExtName);
             if (renderable && !supported) {
                 testFailed("RGBA/FLOAT is color renderable but " + renderableExtName + " not exposed");
             } else if (supported && !renderable) {
                 testFailed(renderableExtName + " is exposed but RGBA/FLOAT is not color renderable");
             }
             if (supported) {
                 runRenderTargetAndReadbackTest(testProgram, gl.RGBA, 4, [10000, 10000, 10000, 10000], 0, true);
                 runRenderTargetAndReadbackTest(testProgram, gl.RGB, 3, [10000, 10000, 10000, 1], 0, false);
                 runRenderTargetAndReadbackTest(testProgram, gl.RGBA, 4, [10000, 10000, 10000, 10000], 1, true);
                 runRenderTargetAndReadbackTest(testProgram, gl.RGBA, 4, [10000, 10000, 10000, 10000], 0.5, true);
             }
         })();

         runUniqueObjectTest();
     }
 }

 function isRenderable(gl) {
     var tex = gl.createTexture();
     gl.bindTexture(gl.TEXTURE_2D, tex);
     gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, 1, 1, 0, gl.RGBA, gl.FLOAT, null);

     var fb = gl.createFramebuffer();
     gl.bindFramebuffer(gl.FRAMEBUFFER, fb);
     gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, tex, 0);

     var status = gl.checkFramebufferStatus(gl.FRAMEBUFFER);
     gl.deleteFramebuffer(fb);
     gl.deleteTexture(tex);

     return status == gl.FRAMEBUFFER_COMPLETE;
 }

 function allocateTexture()
 {
     var texture = gl.createTexture();
     gl.bindTexture(gl.TEXTURE_2D, texture);
     gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST);
     gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST);
     gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
     gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
     wtu.glErrorShouldBe(gl, gl.NO_ERROR, "texture parameter setup should succeed");
     return texture;
 }

 function checkRenderingResults()
 {
     wtu.checkCanvas(gl, [0, 255, 0, 255], "should be green");
 }

 function runTextureCreationTest(testProgram, extensionEnabled, opt_format, opt_numChannels, opt_subtractor)
 {
     var format = opt_format || gl.RGBA;
     var numberOfChannels = opt_numChannels || 4;
     var expectFailure = !extensionEnabled;
     var subtractor = opt_subtractor || [10000, 10000, 10000, 10000];

     debug("");
     debug("testing format: " + wtu.glEnumToString(gl, format) +
           " expect:" + (extensionEnabled ? "success" : "failure"));

     var texture = allocateTexture();
     // Generate data.
     var width = 2;
     var height = 2;
     var data = new Float32Array(width * height * numberOfChannels);
     for (var ii = 0; ii < data.length; ++ii) {
         data[ii] = 10000;
     }
     gl.texImage2D(gl.TEXTURE_2D, 0, format, width, height, 0, format, gl.FLOAT, data);
     if (expectFailure) {
         wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, "floating-point texture allocation must be disallowed if OES_texture_float isn't enabled");
         return;
     } else {
         wtu.glErrorShouldBe(gl, gl.NO_ERROR, "floating-point texture allocation should succeed if OES_texture_float is enabled");
     }
     // Verify that the texture actually works for sampling and contains the expected data.
     gl.uniform4fv(gl.getUniformLocation(testProgram, "subtractor"), subtractor);
     wtu.clearAndDrawUnitQuad(gl);
     checkRenderingResults();

     // Check that linear fails.
     gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
     wtu.clearAndDrawUnitQuad(gl);
     wtu.checkCanvas(gl, [255, 0, 0, 255], "should be red");
 }

 function arrayToString(arr, size) {
     var mySize;
     if (!size)
         mySize = arr.length;
     else
         mySize = size;
     var out = "[";
     for (var ii = 0; ii < mySize; ++ii) {
     if (ii > 0) {
         out += ", ";
     }
     out += arr[ii];
     }
     return out + "]";
 }

 function runRenderTargetAndReadbackTest(testProgram, format, numberOfChannels, subtractor, texSubImageCover, requireRenderable)
 {
     var formatString = wtu.glEnumToString(gl, format);
     debug("");
     debug("testing floating-point " + formatString + " render target" + (texSubImageCover > 0 ? " after calling texSubImage" : ""));

     var texture = allocateTexture();
     var width = 2;
     var height = 2;
     gl.texImage2D(gl.TEXTURE_2D, 0, format, width, height, 0, format, gl.FLOAT, null);
     wtu.glErrorShouldBe(gl, gl.NO_ERROR, "floating-point texture allocation should succeed if OES_texture_float is enabled");

     // Try to use this texture as a render target.
     var fbo = gl.createFramebuffer();
     gl.bindFramebuffer(gl.FRAMEBUFFER, fbo);
     gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, texture, 0);
     gl.bindTexture(gl.TEXTURE_2D, null);
     // It is legal for a WebGL implementation exposing the OES_texture_float extension to
     // support floating-point textures but not as attachments to framebuffer objects.
     if (gl.checkFramebufferStatus(gl.FRAMEBUFFER) != gl.FRAMEBUFFER_COMPLETE) {
         if (requireRenderable)
             testFailed("floating-point " + formatString + " render target not supported");
         else
             debug("floating-point " + formatString + " render target not supported -- this is legal");
         return;
     }

     if (texSubImageCover > 0) {
         // Ensure that replacing the whole texture or a part of it with texSubImage2D doesn't affect renderability
         gl.bindTexture(gl.TEXTURE_2D, texture);
         var data = new Float32Array(width * height * numberOfChannels * texSubImageCover);
         gl.texSubImage2D(gl.TEXTURE_2D, 0, 0, 0, width, height * texSubImageCover, format, gl.FLOAT, data);
         wtu.glErrorShouldBe(gl, gl.NO_ERROR, "texSubImage2D should succeed if OES_texture_float is enabled");
         gl.bindTexture(gl.TEXTURE_2D, null);
         if (gl.checkFramebufferStatus(gl.FRAMEBUFFER) != gl.FRAMEBUFFER_COMPLETE) {
             testFailed("render target support changed after calling texSubImage2D");
             return;
         }
     }

     var renderProgram =
         wtu.setupProgram(gl,
                          ["positionVertexShader", "floatingPointFragmentShader"],
                          ['vPosition'],
                          [0]);
     wtu.clearAndDrawUnitQuad(gl);
     wtu.glErrorShouldBe(gl, gl.NO_ERROR, "rendering to floating-point texture should succeed");

     // Now sample from the floating-point texture and verify we got the correct values.
     gl.bindFramebuffer(gl.FRAMEBUFFER, null);
     gl.bindTexture(gl.TEXTURE_2D, texture);
     gl.useProgram(testProgram);
     gl.uniform1i(gl.getUniformLocation(testProgram, "tex"), 0);
     gl.uniform4fv(gl.getUniformLocation(testProgram, "subtractor"), subtractor);
     wtu.clearAndDrawUnitQuad(gl);
     wtu.glErrorShouldBe(gl, gl.NO_ERROR, "rendering from floating-point texture should succeed");
     checkRenderingResults();

     // Finally, if the implementation supports floating-point readback, verify it.
     gl.bindFramebuffer(gl.FRAMEBUFFER, fbo);
     var implFormat = gl.getParameter(gl.IMPLEMENTATION_COLOR_READ_FORMAT);
     var implType = gl.getParameter(gl.IMPLEMENTATION_COLOR_READ_TYPE);
     wtu.glErrorShouldBe(gl, gl.NO_ERROR, "getParameter of IMPLEMENTATION_COLOR_READ_{FORMAT|TYPE} should succeed");
     if ((implFormat == gl.RGBA || implFormat == gl.RGB) && implType == gl.FLOAT) {
     debug("Checking readback of floating-point values");
     var arraySize = (implFormat == gl.RGBA) ? 4 : 3
     var buf = new Float32Array(arraySize);
     gl.readPixels(0, 0, 1, 1, implFormat, implType , buf);
     wtu.glErrorShouldBe(gl, gl.NO_ERROR, "readPixels from floating-point renderbuffer should succeed");
     var ok = true;
     var tolerance = 8.0; // TODO: factor this out from both this test and the subtractor shader above.
     for (var ii = 0; ii < buf.length; ++ii) {
         if (Math.abs(buf[ii] - subtractor[ii]) > tolerance) {
         ok = false;
         break;
         }
     }
     if (ok) {
         testPassed("readPixels of float-type data from floating-point renderbuffer succeeded");
     } else {
         testFailed("readPixels of float-type data from floating-point renderbuffer failed: expected "
                + arrayToString(subtractor, arraySize) + ", got " + arrayToString(buf));
     }
     }
 }

 function runUniqueObjectTest()
 {
     debug("");
     debug("Testing that getExtension() returns the same object each time");
     gl.getExtension("OES_texture_float").myProperty = 2;
     webglHarnessCollectGarbage();
     shouldBe('gl.getExtension("OES_texture_float").myProperty', '2');
 }


 debug("");
 var successfullyParsed = true;
 </script>
 <script src="../../js/js-test-post.js"></script>

 </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">
	<title>WebGL OES_texture_float Conformance Tests</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>
	<canvas id="canvas" style="width: 50px; height: 50px;"> </canvas>
	<div id="console"></div>
	<!-- Shaders for testing floating-point textures -->
	<script id="testFragmentShader" type="x-shader/x-fragment">
	precision mediump float;
	uniform sampler2D tex;
	uniform vec4 subtractor;
	varying vec2 texCoord;
	void main()
	{
	vec4 color = texture2D(tex, texCoord);
	if (abs(color.r - subtractor.r) +
	abs(color.g - subtractor.g) +
	abs(color.b - subtractor.b) +
	abs(color.a - subtractor.a) < 8.0) {
	gl_FragColor = vec4(0.0, 1.0, 0.0, 1.0);
	} else {
	gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
	}
	}
	</script>
	<!-- Shaders for testing floating-point render targets -->
	<script id="positionVertexShader" type="x-shader/x-vertex">
	attribute vec4 vPosition;
	void main()
	{
	gl_Position = vPosition;
	}
	</script>
	<script id="floatingPointFragmentShader" type="x-shader/x-fragment">
	void main()
	{
	gl_FragColor = vec4(10000.0, 10000.0, 10000.0, 10000.0);
	}
	</script>
	<script>
	"use strict";
	description("This test verifies the functionality of the OES_texture_float extension, if it is available.");

	debug("");

	var wtu = WebGLTestUtils;
	var canvas = document.getElementById("canvas");
	var gl = wtu.create3DContext(canvas);

	if (!gl) {
	testFailed("WebGL context does not exist");
	} else {
	testPassed("WebGL context exists");

	var texturedShaders = [
	wtu.simpleTextureVertexShader,
	"testFragmentShader"
	];
	var testProgram =
	wtu.setupProgram(gl,
	texturedShaders,
	['vPosition', 'texCoord0'],
	[0, 1]);
	var quadParameters = wtu.setupUnitQuad(gl, 0, 1);

	// First verify that allocation of floating-point textures fails if
	// the extension has not been enabled yet.
	runTextureCreationTest(testProgram, false);

	if (!gl.getExtension("OES_texture_float")) {
	testPassed("No OES_texture_float support -- this is legal");
	} else {
	testPassed("Successfully enabled OES_texture_float extension");
	// If alpha value is missing from a texture it gets filled to 1 when sampling according to GLES2.0 table 3.12
	runTextureCreationTest(testProgram, true, gl.RGBA, 4, [10000, 10000, 10000, 10000]);
	runTextureCreationTest(testProgram, true, gl.RGB, 3, [10000, 10000, 10000, 1]);
	runTextureCreationTest(testProgram, true, gl.LUMINANCE, 1, [10000, 10000, 10000, 1]);
	runTextureCreationTest(testProgram, true, gl.ALPHA, 1, [0, 0, 0, 10000]);
	runTextureCreationTest(testProgram, true, gl.LUMINANCE_ALPHA, 2, [10000, 10000, 10000, 10000]);

	(function() {
	debug("");
	var renderable = isRenderable(gl);
	var renderableExtName = "WEBGL_color_buffer_float";
	var supported = gl.getSupportedExtensions().includes(renderableExtName);
	if (renderable && !supported) {
	testFailed("RGBA/FLOAT is color renderable but " + renderableExtName + " not exposed");
	} else if (supported && !renderable) {
	testFailed(renderableExtName + " is exposed but RGBA/FLOAT is not color renderable");
	}
	if (supported) {
	runRenderTargetAndReadbackTest(testProgram, gl.RGBA, 4, [10000, 10000, 10000, 10000], 0, true);
	runRenderTargetAndReadbackTest(testProgram, gl.RGB, 3, [10000, 10000, 10000, 1], 0, false);
	runRenderTargetAndReadbackTest(testProgram, gl.RGBA, 4, [10000, 10000, 10000, 10000], 1, true);
	runRenderTargetAndReadbackTest(testProgram, gl.RGBA, 4, [10000, 10000, 10000, 10000], 0.5, true);
	}
	})();

	runUniqueObjectTest();
	}
	}

	function isRenderable(gl) {
	var tex = gl.createTexture();
	gl.bindTexture(gl.TEXTURE_2D, tex);
	gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, 1, 1, 0, gl.RGBA, gl.FLOAT, null);

	var fb = gl.createFramebuffer();
	gl.bindFramebuffer(gl.FRAMEBUFFER, fb);
	gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, tex, 0);

	var status = gl.checkFramebufferStatus(gl.FRAMEBUFFER);
	gl.deleteFramebuffer(fb);
	gl.deleteTexture(tex);

	return status == gl.FRAMEBUFFER_COMPLETE;
	}

	function allocateTexture()
	{
	var texture = gl.createTexture();
	gl.bindTexture(gl.TEXTURE_2D, texture);
	gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST);
	gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST);
	gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
	gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
	wtu.glErrorShouldBe(gl, gl.NO_ERROR, "texture parameter setup should succeed");
	return texture;
	}

	function checkRenderingResults()
	{
	wtu.checkCanvas(gl, [0, 255, 0, 255], "should be green");
	}

	function runTextureCreationTest(testProgram, extensionEnabled, opt_format, opt_numChannels, opt_subtractor)
	{
	var format = opt_format \|\| gl.RGBA;
	var numberOfChannels = opt_numChannels \|\| 4;
	var expectFailure = !extensionEnabled;
	var subtractor = opt_subtractor \|\| [10000, 10000, 10000, 10000];

	debug("");
	debug("testing format: " + wtu.glEnumToString(gl, format) +
	" expect:" + (extensionEnabled ? "success" : "failure"));

	var texture = allocateTexture();
	// Generate data.
	var width = 2;
	var height = 2;
	var data = new Float32Array(width * height * numberOfChannels);
	for (var ii = 0; ii < data.length; ++ii) {
	data[ii] = 10000;
	}
	gl.texImage2D(gl.TEXTURE_2D, 0, format, width, height, 0, format, gl.FLOAT, data);
	if (expectFailure) {
	wtu.glErrorShouldBe(gl, gl.INVALID_ENUM, "floating-point texture allocation must be disallowed if OES_texture_float isn't enabled");
	return;
	} else {
	wtu.glErrorShouldBe(gl, gl.NO_ERROR, "floating-point texture allocation should succeed if OES_texture_float is enabled");
	}
	// Verify that the texture actually works for sampling and contains the expected data.
	gl.uniform4fv(gl.getUniformLocation(testProgram, "subtractor"), subtractor);
	wtu.clearAndDrawUnitQuad(gl);
	checkRenderingResults();

	// Check that linear fails.
	gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
	wtu.clearAndDrawUnitQuad(gl);
	wtu.checkCanvas(gl, [255, 0, 0, 255], "should be red");
	}

	function arrayToString(arr, size) {
	var mySize;
	if (!size)
	mySize = arr.length;
	else
	mySize = size;
	var out = "[";
	for (var ii = 0; ii < mySize; ++ii) {
	if (ii > 0) {
	out += ", ";
	}
	out += arr[ii];
	}
	return out + "]";
	}

	function runRenderTargetAndReadbackTest(testProgram, format, numberOfChannels, subtractor, texSubImageCover, requireRenderable)
	{
	var formatString = wtu.glEnumToString(gl, format);
	debug("");
	debug("testing floating-point " + formatString + " render target" + (texSubImageCover > 0 ? " after calling texSubImage" : ""));

	var texture = allocateTexture();
	var width = 2;
	var height = 2;
	gl.texImage2D(gl.TEXTURE_2D, 0, format, width, height, 0, format, gl.FLOAT, null);
	wtu.glErrorShouldBe(gl, gl.NO_ERROR, "floating-point texture allocation should succeed if OES_texture_float is enabled");

	// Try to use this texture as a render target.
	var fbo = gl.createFramebuffer();
	gl.bindFramebuffer(gl.FRAMEBUFFER, fbo);
	gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, texture, 0);
	gl.bindTexture(gl.TEXTURE_2D, null);
	// It is legal for a WebGL implementation exposing the OES_texture_float extension to
	// support floating-point textures but not as attachments to framebuffer objects.
	if (gl.checkFramebufferStatus(gl.FRAMEBUFFER) != gl.FRAMEBUFFER_COMPLETE) {
	if (requireRenderable)
	testFailed("floating-point " + formatString + " render target not supported");
	else
	debug("floating-point " + formatString + " render target not supported -- this is legal");
	return;
	}

	if (texSubImageCover > 0) {
	// Ensure that replacing the whole texture or a part of it with texSubImage2D doesn't affect renderability
	gl.bindTexture(gl.TEXTURE_2D, texture);
	var data = new Float32Array(width * height * numberOfChannels * texSubImageCover);
	gl.texSubImage2D(gl.TEXTURE_2D, 0, 0, 0, width, height * texSubImageCover, format, gl.FLOAT, data);
	wtu.glErrorShouldBe(gl, gl.NO_ERROR, "texSubImage2D should succeed if OES_texture_float is enabled");
	gl.bindTexture(gl.TEXTURE_2D, null);
	if (gl.checkFramebufferStatus(gl.FRAMEBUFFER) != gl.FRAMEBUFFER_COMPLETE) {
	testFailed("render target support changed after calling texSubImage2D");
	return;
	}
	}

	var renderProgram =
	wtu.setupProgram(gl,
	["positionVertexShader", "floatingPointFragmentShader"],
	['vPosition'],
	[0]);
	wtu.clearAndDrawUnitQuad(gl);
	wtu.glErrorShouldBe(gl, gl.NO_ERROR, "rendering to floating-point texture should succeed");

	// Now sample from the floating-point texture and verify we got the correct values.
	gl.bindFramebuffer(gl.FRAMEBUFFER, null);
	gl.bindTexture(gl.TEXTURE_2D, texture);
	gl.useProgram(testProgram);
	gl.uniform1i(gl.getUniformLocation(testProgram, "tex"), 0);
	gl.uniform4fv(gl.getUniformLocation(testProgram, "subtractor"), subtractor);
	wtu.clearAndDrawUnitQuad(gl);
	wtu.glErrorShouldBe(gl, gl.NO_ERROR, "rendering from floating-point texture should succeed");
	checkRenderingResults();

	// Finally, if the implementation supports floating-point readback, verify it.
	gl.bindFramebuffer(gl.FRAMEBUFFER, fbo);
	var implFormat = gl.getParameter(gl.IMPLEMENTATION_COLOR_READ_FORMAT);
	var implType = gl.getParameter(gl.IMPLEMENTATION_COLOR_READ_TYPE);
	wtu.glErrorShouldBe(gl, gl.NO_ERROR, "getParameter of IMPLEMENTATION_COLOR_READ_{FORMAT\|TYPE} should succeed");
	if ((implFormat == gl.RGBA \|\| implFormat == gl.RGB) && implType == gl.FLOAT) {
	debug("Checking readback of floating-point values");
	var arraySize = (implFormat == gl.RGBA) ? 4 : 3
	var buf = new Float32Array(arraySize);
	gl.readPixels(0, 0, 1, 1, implFormat, implType , buf);
	wtu.glErrorShouldBe(gl, gl.NO_ERROR, "readPixels from floating-point renderbuffer should succeed");
	var ok = true;
	var tolerance = 8.0; // TODO: factor this out from both this test and the subtractor shader above.
	for (var ii = 0; ii < buf.length; ++ii) {
	if (Math.abs(buf[ii] - subtractor[ii]) > tolerance) {
	ok = false;
	break;
	}
	}
	if (ok) {
	testPassed("readPixels of float-type data from floating-point renderbuffer succeeded");
	} else {
	testFailed("readPixels of float-type data from floating-point renderbuffer failed: expected "
	+ arrayToString(subtractor, arraySize) + ", got " + arrayToString(buf));
	}
	}
	}

	function runUniqueObjectTest()
	{
	debug("");
	debug("Testing that getExtension() returns the same object each time");
	gl.getExtension("OES_texture_float").myProperty = 2;
	webglHarnessCollectGarbage();
	shouldBe('gl.getExtension("OES_texture_float").myProperty', '2');
	}


	debug("");
	var successfullyParsed = true;
	</script>
	<script src="../../js/js-test-post.js"></script>

	</body>
	</html>