third_party/angle/src/tests/gl_tests/WebGLReadOutsideFramebufferTest.cpp - cobalt - Git at Google

 //
 // Copyright 2017 The ANGLE Project Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //

 // WebGLReadOutsideFramebufferTest.cpp : Test functions which read the framebuffer (readPixels,
 // copyTexSubImage2D, copyTexImage2D) on areas outside the framebuffer.

 #include "test_utils/ANGLETest.h"

 #include "test_utils/gl_raii.h"

 namespace
 {

 class PixelRect
 {
   public:
     PixelRect(int width, int height) : mWidth(width), mHeight(height), mData(width * height) {}

     // Set each pixel to a different color consisting of the x,y position and a given tag.
     // Making each pixel a different means any misplaced pixel will cause a failure.
     // Encoding the position proved valuable in debugging.
     void fill(unsigned tag)
     {
         for (int x = 0; x < mWidth; ++x)
         {
             for (int y = 0; y < mHeight; ++y)
             {
                 mData[x + y * mWidth] = angle::GLColor(x + (y << 8) + (tag << 16));
             }
         }
     }

     void toTexture2D(GLuint target, GLuint texid) const
     {
         glBindTexture(target, texid);
         if (target == GL_TEXTURE_CUBE_MAP)
         {
             glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X, 0, GL_RGBA, mWidth, mHeight, 0, GL_RGBA,
                          GL_UNSIGNED_BYTE, mData.data());
             glTexImage2D(GL_TEXTURE_CUBE_MAP_NEGATIVE_X, 0, GL_RGBA, mWidth, mHeight, 0, GL_RGBA,
                          GL_UNSIGNED_BYTE, mData.data());
             glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_Y, 0, GL_RGBA, mWidth, mHeight, 0, GL_RGBA,
                          GL_UNSIGNED_BYTE, mData.data());
             glTexImage2D(GL_TEXTURE_CUBE_MAP_NEGATIVE_Y, 0, GL_RGBA, mWidth, mHeight, 0, GL_RGBA,
                          GL_UNSIGNED_BYTE, mData.data());
             glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_Z, 0, GL_RGBA, mWidth, mHeight, 0, GL_RGBA,
                          GL_UNSIGNED_BYTE, mData.data());
             glTexImage2D(GL_TEXTURE_CUBE_MAP_NEGATIVE_Z, 0, GL_RGBA, mWidth, mHeight, 0, GL_RGBA,
                          GL_UNSIGNED_BYTE, mData.data());
         }
         else
         {
             ASSERT_GLENUM_EQ(GL_TEXTURE_2D, target);
             glTexImage2D(target, 0, GL_RGBA, mWidth, mHeight, 0, GL_RGBA, GL_UNSIGNED_BYTE,
                          mData.data());
         }
         glTexParameteri(target, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
         glTexParameteri(target, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
         glTexParameteri(target, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
         glTexParameteri(target, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
     }

     void toTexture3D(GLuint texid, GLint depth) const
     {
         glBindTexture(GL_TEXTURE_3D, texid);

         glTexImage3D(GL_TEXTURE_3D, 0, GL_RGBA, mWidth, mHeight, depth, 0, GL_RGBA,
                      GL_UNSIGNED_BYTE, nullptr);
         for (GLint z = 0; z < depth; z++)
         {
             glTexSubImage3D(GL_TEXTURE_3D, 0, 0, 0, z, mWidth, mHeight, 1, GL_RGBA,
                             GL_UNSIGNED_BYTE, mData.data());
         }
         glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
         glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
         glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
         glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
         glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
     }

     void readFB(int x, int y)
     {
         glReadPixels(x, y, mWidth, mHeight, GL_RGBA, GL_UNSIGNED_BYTE, mData.data());
     }

     // Read pixels from 'other' into 'this' from position (x,y).
     // Pixels outside 'other' are untouched or zeroed according to 'zeroOutside.'
     void readPixelRect(const PixelRect &other, int x, int y, bool zeroOutside)
     {
         for (int i = 0; i < mWidth; ++i)
         {
             for (int j = 0; j < mHeight; ++j)
             {
                 angle::GLColor *dest = &mData[i + j * mWidth];
                 if (!other.getPixel(x + i, y + j, dest) && zeroOutside)
                 {
                     *dest = angle::GLColor(0);
                 }
             }
         }
     }

     bool getPixel(int x, int y, angle::GLColor *colorOut) const
     {
         if (0 <= x && x < mWidth && 0 <= y && y < mHeight)
         {
             *colorOut = mData[x + y * mWidth];
             return true;
         }
         return false;
     }

     void compare(const PixelRect &expected) const
     {
         ASSERT_EQ(mWidth, expected.mWidth);
         ASSERT_EQ(mHeight, expected.mHeight);

         for (int x = 0; x < mWidth; ++x)
         {
             for (int y = 0; y < mHeight; ++y)
             {
                 ASSERT_EQ(expected.mData[x + y * mWidth], mData[x + y * mWidth])
                     << "at (" << x << ", " << y << ")";
             }
         }
     }

   private:
     int mWidth, mHeight;
     std::vector<angle::GLColor> mData;
 };

 }  // namespace

 namespace angle
 {

 class WebGLReadOutsideFramebufferTest : public ANGLETest
 {
   public:
     // Read framebuffer to 'pixelsOut' via glReadPixels.
     void TestReadPixels(int x, int y, int, PixelRect *pixelsOut) { pixelsOut->readFB(x, y); }

     // Read framebuffer to 'pixelsOut' via glCopyTexSubImage2D and GL_TEXTURE_2D.
     void TestCopyTexSubImage2D(int x, int y, int, PixelRect *pixelsOut)
     {
         // Init texture with given pixels.
         GLTexture destTexture;
         pixelsOut->toTexture2D(GL_TEXTURE_2D, destTexture.get());

         // Read framebuffer -> texture -> 'pixelsOut'
         glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, x, y, kReadWidth, kReadHeight);
         readTexture2D(GL_TEXTURE_2D, destTexture.get(), kReadWidth, kReadHeight, pixelsOut);
     }

     // Read framebuffer to 'pixelsOut' via glCopyTexSubImage2D and cube map.
     void TestCopyTexSubImageCube(int x, int y, int, PixelRect *pixelsOut)
     {
         // Init texture with given pixels.
         GLTexture destTexture;
         pixelsOut->toTexture2D(GL_TEXTURE_CUBE_MAP, destTexture.get());

         // Read framebuffer -> texture -> 'pixelsOut'
         glCopyTexSubImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X, 0, 0, 0, x, y, kReadWidth, kReadHeight);
         readTexture2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X, destTexture.get(), kReadWidth, kReadHeight,
                       pixelsOut);
     }

     // Read framebuffer to 'pixelsOut' via glCopyTexSubImage3D.
     void TestCopyTexSubImage3D(int x, int y, int z, PixelRect *pixelsOut)
     {
         // Init texture with given pixels.
         GLTexture destTexture;
         pixelsOut->toTexture3D(destTexture.get(), kTextureDepth);

         // Read framebuffer -> texture -> 'pixelsOut'
         glCopyTexSubImage3D(GL_TEXTURE_3D, 0, 0, 0, z, x, y, kReadWidth, kReadHeight);
         readTexture3D(destTexture, kReadWidth, kReadHeight, z, pixelsOut);
     }

     // Read framebuffer to 'pixelsOut' via glCopyTexImage2D and GL_TEXTURE_2D.
     void TestCopyTexImage2D(int x, int y, int, PixelRect *pixelsOut)
     {
         // Init texture with given pixels.
         GLTexture destTexture;
         pixelsOut->toTexture2D(GL_TEXTURE_2D, destTexture.get());

         // Read framebuffer -> texture -> 'pixelsOut'
         glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, x, y, kReadWidth, kReadHeight, 0);
         readTexture2D(GL_TEXTURE_2D, destTexture.get(), kReadWidth, kReadHeight, pixelsOut);
     }

     // Read framebuffer to 'pixelsOut' via glCopyTexImage2D and cube map.
     void TestCopyTexImageCube(int x, int y, int, PixelRect *pixelsOut)
     {
         // Init texture with given pixels.
         GLTexture destTexture;
         pixelsOut->toTexture2D(GL_TEXTURE_CUBE_MAP, destTexture.get());

         // Read framebuffer -> texture -> 'pixelsOut'
         glCopyTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X, 0, GL_RGBA, x, y, kReadWidth, kReadHeight,
                          0);
         readTexture2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X, destTexture, kReadWidth, kReadHeight,
                       pixelsOut);
     }

   protected:
     static constexpr int kFbWidth      = 128;
     static constexpr int kFbHeight     = 128;
     static constexpr int kTextureDepth = 16;
     static constexpr int kReadWidth    = 4;
     static constexpr int kReadHeight   = 4;
     static constexpr int kReadLayer    = 2;

     // Tag the framebuffer pixels differently than the initial read buffer pixels, so we know for
     // sure which pixels are changed by reading.
     static constexpr GLuint fbTag   = 0x1122;
     static constexpr GLuint readTag = 0xaabb;

     WebGLReadOutsideFramebufferTest() : mFBData(kFbWidth, kFbHeight)
     {
         setWindowWidth(kFbWidth);
         setWindowHeight(kFbHeight);
         setConfigRedBits(8);
         setConfigGreenBits(8);
         setConfigBlueBits(8);
         setConfigAlphaBits(8);
         setWebGLCompatibilityEnabled(true);
     }

     void testSetUp() override
     {
         constexpr char kVS[] = R"(
 attribute vec3 a_position;
 varying vec2 v_texCoord;
 void main() {
     v_texCoord = a_position.xy * 0.5 + 0.5;
     gl_Position = vec4(a_position, 1);
 })";
         constexpr char kFS[] = R"(
 precision mediump float;
 varying vec2 v_texCoord;
 uniform sampler2D u_texture;
 void main() {
     gl_FragColor = texture2D(u_texture, v_texCoord);
 })";

         mProgram = CompileProgram(kVS, kFS);
         glUseProgram(mProgram);
         GLint uniformLoc = glGetUniformLocation(mProgram, "u_texture");
         ASSERT_NE(-1, uniformLoc);
         glUniform1i(uniformLoc, 0);

         glDisable(GL_BLEND);
         glDisable(GL_DEPTH_TEST);

         // fill framebuffer with unique pixels
         mFBData.fill(fbTag);
         GLTexture fbTexture;
         mFBData.toTexture2D(GL_TEXTURE_2D, fbTexture);
         drawQuad(mProgram, "a_position", 0.0f, 1.0f, true);
     }

     void testTearDown() override { glDeleteProgram(mProgram); }

     using TestFunc = void (WebGLReadOutsideFramebufferTest::*)(int x,
                                                                int y,
                                                                int z,
                                                                PixelRect *dest);

     void Main2D(TestFunc testFunc, bool zeroOutside) { mainImpl(testFunc, zeroOutside, 0); }

     void Main3D(TestFunc testFunc, bool zeroOutside)
     {
         mainImpl(testFunc, zeroOutside, kReadLayer);
     }

     void mainImpl(TestFunc testFunc, bool zeroOutside, int readLayer)
     {
         PixelRect actual(kReadWidth, kReadHeight);
         PixelRect expected(kReadWidth, kReadHeight);

         // Read a kReadWidth*kReadHeight rectangle of pixels from places that include:
         // - completely outside framebuffer, on all sides of it (i,j < 0 or > 2)
         // - completely inside framebuffer (i,j == 1)
         // - straddling framebuffer boundary, at each corner and side
         for (int i = -1; i < 4; ++i)
         {
             for (int j = -1; j < 4; ++j)
             {
                 int x = i * kFbWidth / 2 - kReadWidth / 2;
                 int y = j * kFbHeight / 2 - kReadHeight / 2;

                 // Put unique pixel values into the read destinations.
                 actual.fill(readTag);
                 expected.readPixelRect(actual, 0, 0, false);

                 // Read from framebuffer into 'actual.'
                 glBindFramebuffer(GL_FRAMEBUFFER, 0);
                 (this->*testFunc)(x, y, readLayer, &actual);
                 glBindFramebuffer(GL_FRAMEBUFFER, 0);

                 // Simulate framebuffer read, into 'expected.'
                 expected.readPixelRect(mFBData, x, y, zeroOutside);

                 // See if they are the same.
                 actual.compare(expected);
             }
         }
     }

     // Get contents of given texture by drawing it into a framebuffer then reading with
     // glReadPixels().
     void readTexture2D(GLuint target, GLuint texture, GLsizei width, GLsizei height, PixelRect *out)
     {
         GLFramebuffer fbo;
         glBindFramebuffer(GL_FRAMEBUFFER, fbo);
         glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, target, texture, 0);
         out->readFB(0, 0);
     }

     // Get contents of current texture by drawing it into a framebuffer then reading with
     // glReadPixels().
     void readTexture3D(GLuint texture, GLsizei width, GLsizei height, int zSlice, PixelRect *out)
     {
         GLFramebuffer fbo;
         glBindFramebuffer(GL_FRAMEBUFFER, fbo);
         glFramebufferTextureLayer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, texture, 0, zSlice);
         out->readFB(0, 0);
     }

     PixelRect mFBData;
     GLuint mProgram;
 };

 class WebGL2ReadOutsideFramebufferTest : public WebGLReadOutsideFramebufferTest
 {};

 // Check that readPixels does not set a destination pixel when
 // the corresponding source pixel is outside the framebuffer.
 TEST_P(WebGLReadOutsideFramebufferTest, ReadPixels)
 {
     Main2D(&WebGLReadOutsideFramebufferTest::TestReadPixels, false);
 }

 // Check that copyTexSubImage2D does not set a destination pixel when
 // the corresponding source pixel is outside the framebuffer.
 TEST_P(WebGLReadOutsideFramebufferTest, CopyTexSubImage2D)
 {
     Main2D(&WebGLReadOutsideFramebufferTest::TestCopyTexSubImage2D, false);

     // TODO(fjhenigman): Figure out this failure.
     // Cube map skipped on 64-bit Windows with D3D FL 9.3
     ANGLE_SKIP_TEST_IF(GetParam() == ES2_D3D11_FL9_3());

     Main2D(&WebGLReadOutsideFramebufferTest::TestCopyTexSubImageCube, false);
 }

 // Check that copyTexImage2D sets (0,0,0,0) for pixels outside the framebuffer.
 TEST_P(WebGLReadOutsideFramebufferTest, CopyTexImage2D)
 {
     // http://anglebug.com/4092
     ANGLE_SKIP_TEST_IF(IsVulkan() || IsD3D9() || IsD3D11());
     Main2D(&WebGLReadOutsideFramebufferTest::TestCopyTexImage2D, true);

     // TODO(fjhenigman): Figure out this failure.
     // Cube map skipped on 64-bit Windows with D3D FL 9.3
     ANGLE_SKIP_TEST_IF(GetParam() == ES2_D3D11_FL9_3());

     Main2D(&WebGLReadOutsideFramebufferTest::TestCopyTexImageCube, true);
 }

 // Check that copyTexSubImage3D does not set a destination pixel when
 // the corresponding source pixel is outside the framebuffer.
 TEST_P(WebGL2ReadOutsideFramebufferTest, CopyTexSubImage3D)
 {
     // TODO(hqle): Metal doesn't implement 3D texture yet.
     // http://anglebug.com/4136 (ES2 renderer is mistakenly included in this test)
     ANGLE_SKIP_TEST_IF(IsMetal());
     // http://anglebug.com/4092
     ANGLE_SKIP_TEST_IF(IsVulkan() || IsD3D9() || IsD3D11());
     // Robust CopyTexSubImage3D behaviour is not implemented on OpenGL.
     ANGLE_SKIP_TEST_IF(IsDesktopOpenGL() || IsOpenGLES());

     Main3D(&WebGLReadOutsideFramebufferTest::TestCopyTexSubImage3D, false);
 }

 ANGLE_INSTANTIATE_TEST_ES2_AND_ES3(WebGLReadOutsideFramebufferTest);

 ANGLE_INSTANTIATE_TEST_ES2_AND_ES3(WebGL2ReadOutsideFramebufferTest);

 }  // namespace angle
	//
	// Copyright 2017 The ANGLE Project Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.
	//

	// WebGLReadOutsideFramebufferTest.cpp : Test functions which read the framebuffer (readPixels,
	// copyTexSubImage2D, copyTexImage2D) on areas outside the framebuffer.

	#include "test_utils/ANGLETest.h"

	#include "test_utils/gl_raii.h"

	namespace
	{

	class PixelRect
	{
	public:
	PixelRect(int width, int height) : mWidth(width), mHeight(height), mData(width * height) {}

	// Set each pixel to a different color consisting of the x,y position and a given tag.
	// Making each pixel a different means any misplaced pixel will cause a failure.
	// Encoding the position proved valuable in debugging.
	void fill(unsigned tag)
	{
	for (int x = 0; x < mWidth; ++x)
	{
	for (int y = 0; y < mHeight; ++y)
	{
	mData[x + y * mWidth] = angle::GLColor(x + (y << 8) + (tag << 16));
	}
	}
	}

	void toTexture2D(GLuint target, GLuint texid) const
	{
	glBindTexture(target, texid);
	if (target == GL_TEXTURE_CUBE_MAP)
	{
	glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X, 0, GL_RGBA, mWidth, mHeight, 0, GL_RGBA,
	GL_UNSIGNED_BYTE, mData.data());
	glTexImage2D(GL_TEXTURE_CUBE_MAP_NEGATIVE_X, 0, GL_RGBA, mWidth, mHeight, 0, GL_RGBA,
	GL_UNSIGNED_BYTE, mData.data());
	glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_Y, 0, GL_RGBA, mWidth, mHeight, 0, GL_RGBA,
	GL_UNSIGNED_BYTE, mData.data());
	glTexImage2D(GL_TEXTURE_CUBE_MAP_NEGATIVE_Y, 0, GL_RGBA, mWidth, mHeight, 0, GL_RGBA,
	GL_UNSIGNED_BYTE, mData.data());
	glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_Z, 0, GL_RGBA, mWidth, mHeight, 0, GL_RGBA,
	GL_UNSIGNED_BYTE, mData.data());
	glTexImage2D(GL_TEXTURE_CUBE_MAP_NEGATIVE_Z, 0, GL_RGBA, mWidth, mHeight, 0, GL_RGBA,
	GL_UNSIGNED_BYTE, mData.data());
	}
	else
	{
	ASSERT_GLENUM_EQ(GL_TEXTURE_2D, target);
	glTexImage2D(target, 0, GL_RGBA, mWidth, mHeight, 0, GL_RGBA, GL_UNSIGNED_BYTE,
	mData.data());
	}
	glTexParameteri(target, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
	glTexParameteri(target, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
	glTexParameteri(target, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
	glTexParameteri(target, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
	}

	void toTexture3D(GLuint texid, GLint depth) const
	{
	glBindTexture(GL_TEXTURE_3D, texid);

	glTexImage3D(GL_TEXTURE_3D, 0, GL_RGBA, mWidth, mHeight, depth, 0, GL_RGBA,
	GL_UNSIGNED_BYTE, nullptr);
	for (GLint z = 0; z < depth; z++)
	{
	glTexSubImage3D(GL_TEXTURE_3D, 0, 0, 0, z, mWidth, mHeight, 1, GL_RGBA,
	GL_UNSIGNED_BYTE, mData.data());
	}
	glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
	glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
	glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
	glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
	glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
	}

	void readFB(int x, int y)
	{
	glReadPixels(x, y, mWidth, mHeight, GL_RGBA, GL_UNSIGNED_BYTE, mData.data());
	}

	// Read pixels from 'other' into 'this' from position (x,y).
	// Pixels outside 'other' are untouched or zeroed according to 'zeroOutside.'
	void readPixelRect(const PixelRect &other, int x, int y, bool zeroOutside)
	{
	for (int i = 0; i < mWidth; ++i)
	{
	for (int j = 0; j < mHeight; ++j)
	{
	angle::GLColor dest = &mData[i + j mWidth];
	if (!other.getPixel(x + i, y + j, dest) && zeroOutside)
	{
	*dest = angle::GLColor(0);
	}
	}
	}
	}

	bool getPixel(int x, int y, angle::GLColor *colorOut) const
	{
	if (0 <= x && x < mWidth && 0 <= y && y < mHeight)
	{
	colorOut = mData[x + y mWidth];
	return true;
	}
	return false;
	}

	void compare(const PixelRect &expected) const
	{
	ASSERT_EQ(mWidth, expected.mWidth);
	ASSERT_EQ(mHeight, expected.mHeight);

	for (int x = 0; x < mWidth; ++x)
	{
	for (int y = 0; y < mHeight; ++y)
	{
	ASSERT_EQ(expected.mData[x + y * mWidth], mData[x + y * mWidth])
	<< "at (" << x << ", " << y << ")";
	}
	}
	}

	private:
	int mWidth, mHeight;
	std::vector<angle::GLColor> mData;
	};

	} // namespace

	namespace angle
	{

	class WebGLReadOutsideFramebufferTest : public ANGLETest
	{
	public:
	// Read framebuffer to 'pixelsOut' via glReadPixels.
	void TestReadPixels(int x, int y, int, PixelRect *pixelsOut) { pixelsOut->readFB(x, y); }

	// Read framebuffer to 'pixelsOut' via glCopyTexSubImage2D and GL_TEXTURE_2D.
	void TestCopyTexSubImage2D(int x, int y, int, PixelRect *pixelsOut)
	{
	// Init texture with given pixels.
	GLTexture destTexture;
	pixelsOut->toTexture2D(GL_TEXTURE_2D, destTexture.get());

	// Read framebuffer -> texture -> 'pixelsOut'
	glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, x, y, kReadWidth, kReadHeight);
	readTexture2D(GL_TEXTURE_2D, destTexture.get(), kReadWidth, kReadHeight, pixelsOut);
	}

	// Read framebuffer to 'pixelsOut' via glCopyTexSubImage2D and cube map.
	void TestCopyTexSubImageCube(int x, int y, int, PixelRect *pixelsOut)
	{
	// Init texture with given pixels.
	GLTexture destTexture;
	pixelsOut->toTexture2D(GL_TEXTURE_CUBE_MAP, destTexture.get());

	// Read framebuffer -> texture -> 'pixelsOut'
	glCopyTexSubImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X, 0, 0, 0, x, y, kReadWidth, kReadHeight);
	readTexture2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X, destTexture.get(), kReadWidth, kReadHeight,
	pixelsOut);
	}

	// Read framebuffer to 'pixelsOut' via glCopyTexSubImage3D.
	void TestCopyTexSubImage3D(int x, int y, int z, PixelRect *pixelsOut)
	{
	// Init texture with given pixels.
	GLTexture destTexture;
	pixelsOut->toTexture3D(destTexture.get(), kTextureDepth);

	// Read framebuffer -> texture -> 'pixelsOut'
	glCopyTexSubImage3D(GL_TEXTURE_3D, 0, 0, 0, z, x, y, kReadWidth, kReadHeight);
	readTexture3D(destTexture, kReadWidth, kReadHeight, z, pixelsOut);
	}

	// Read framebuffer to 'pixelsOut' via glCopyTexImage2D and GL_TEXTURE_2D.
	void TestCopyTexImage2D(int x, int y, int, PixelRect *pixelsOut)
	{
	// Init texture with given pixels.
	GLTexture destTexture;
	pixelsOut->toTexture2D(GL_TEXTURE_2D, destTexture.get());

	// Read framebuffer -> texture -> 'pixelsOut'
	glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, x, y, kReadWidth, kReadHeight, 0);
	readTexture2D(GL_TEXTURE_2D, destTexture.get(), kReadWidth, kReadHeight, pixelsOut);
	}

	// Read framebuffer to 'pixelsOut' via glCopyTexImage2D and cube map.
	void TestCopyTexImageCube(int x, int y, int, PixelRect *pixelsOut)
	{
	// Init texture with given pixels.
	GLTexture destTexture;
	pixelsOut->toTexture2D(GL_TEXTURE_CUBE_MAP, destTexture.get());

	// Read framebuffer -> texture -> 'pixelsOut'
	glCopyTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X, 0, GL_RGBA, x, y, kReadWidth, kReadHeight,
	0);
	readTexture2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X, destTexture, kReadWidth, kReadHeight,
	pixelsOut);
	}

	protected:
	static constexpr int kFbWidth = 128;
	static constexpr int kFbHeight = 128;
	static constexpr int kTextureDepth = 16;
	static constexpr int kReadWidth = 4;
	static constexpr int kReadHeight = 4;
	static constexpr int kReadLayer = 2;

	// Tag the framebuffer pixels differently than the initial read buffer pixels, so we know for
	// sure which pixels are changed by reading.
	static constexpr GLuint fbTag = 0x1122;
	static constexpr GLuint readTag = 0xaabb;

	WebGLReadOutsideFramebufferTest() : mFBData(kFbWidth, kFbHeight)
	{
	setWindowWidth(kFbWidth);
	setWindowHeight(kFbHeight);
	setConfigRedBits(8);
	setConfigGreenBits(8);
	setConfigBlueBits(8);
	setConfigAlphaBits(8);
	setWebGLCompatibilityEnabled(true);
	}

	void testSetUp() override
	{
	constexpr char kVS[] = R"(
	attribute vec3 a_position;
	varying vec2 v_texCoord;
	void main() {
	v_texCoord = a_position.xy * 0.5 + 0.5;
	gl_Position = vec4(a_position, 1);
	})";
	constexpr char kFS[] = R"(
	precision mediump float;
	varying vec2 v_texCoord;
	uniform sampler2D u_texture;
	void main() {
	gl_FragColor = texture2D(u_texture, v_texCoord);
	})";

	mProgram = CompileProgram(kVS, kFS);
	glUseProgram(mProgram);
	GLint uniformLoc = glGetUniformLocation(mProgram, "u_texture");
	ASSERT_NE(-1, uniformLoc);
	glUniform1i(uniformLoc, 0);

	glDisable(GL_BLEND);
	glDisable(GL_DEPTH_TEST);

	// fill framebuffer with unique pixels
	mFBData.fill(fbTag);
	GLTexture fbTexture;
	mFBData.toTexture2D(GL_TEXTURE_2D, fbTexture);
	drawQuad(mProgram, "a_position", 0.0f, 1.0f, true);
	}

	void testTearDown() override { glDeleteProgram(mProgram); }

	using TestFunc = void (WebGLReadOutsideFramebufferTest::*)(int x,
	int y,
	int z,
	PixelRect *dest);

	void Main2D(TestFunc testFunc, bool zeroOutside) { mainImpl(testFunc, zeroOutside, 0); }

	void Main3D(TestFunc testFunc, bool zeroOutside)
	{
	mainImpl(testFunc, zeroOutside, kReadLayer);
	}

	void mainImpl(TestFunc testFunc, bool zeroOutside, int readLayer)
	{
	PixelRect actual(kReadWidth, kReadHeight);
	PixelRect expected(kReadWidth, kReadHeight);

	// Read a kReadWidth*kReadHeight rectangle of pixels from places that include:
	// - completely outside framebuffer, on all sides of it (i,j < 0 or > 2)
	// - completely inside framebuffer (i,j == 1)
	// - straddling framebuffer boundary, at each corner and side
	for (int i = -1; i < 4; ++i)
	{
	for (int j = -1; j < 4; ++j)
	{
	int x = i * kFbWidth / 2 - kReadWidth / 2;
	int y = j * kFbHeight / 2 - kReadHeight / 2;

	// Put unique pixel values into the read destinations.
	actual.fill(readTag);
	expected.readPixelRect(actual, 0, 0, false);

	// Read from framebuffer into 'actual.'
	glBindFramebuffer(GL_FRAMEBUFFER, 0);
	(this->*testFunc)(x, y, readLayer, &actual);
	glBindFramebuffer(GL_FRAMEBUFFER, 0);

	// Simulate framebuffer read, into 'expected.'
	expected.readPixelRect(mFBData, x, y, zeroOutside);

	// See if they are the same.
	actual.compare(expected);
	}
	}
	}

	// Get contents of given texture by drawing it into a framebuffer then reading with
	// glReadPixels().
	void readTexture2D(GLuint target, GLuint texture, GLsizei width, GLsizei height, PixelRect *out)
	{
	GLFramebuffer fbo;
	glBindFramebuffer(GL_FRAMEBUFFER, fbo);
	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, target, texture, 0);
	out->readFB(0, 0);
	}

	// Get contents of current texture by drawing it into a framebuffer then reading with
	// glReadPixels().
	void readTexture3D(GLuint texture, GLsizei width, GLsizei height, int zSlice, PixelRect *out)
	{
	GLFramebuffer fbo;
	glBindFramebuffer(GL_FRAMEBUFFER, fbo);
	glFramebufferTextureLayer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, texture, 0, zSlice);
	out->readFB(0, 0);
	}

	PixelRect mFBData;
	GLuint mProgram;
	};

	class WebGL2ReadOutsideFramebufferTest : public WebGLReadOutsideFramebufferTest
	{};

	// Check that readPixels does not set a destination pixel when
	// the corresponding source pixel is outside the framebuffer.
	TEST_P(WebGLReadOutsideFramebufferTest, ReadPixels)
	{
	Main2D(&WebGLReadOutsideFramebufferTest::TestReadPixels, false);
	}

	// Check that copyTexSubImage2D does not set a destination pixel when
	// the corresponding source pixel is outside the framebuffer.
	TEST_P(WebGLReadOutsideFramebufferTest, CopyTexSubImage2D)
	{
	Main2D(&WebGLReadOutsideFramebufferTest::TestCopyTexSubImage2D, false);

	// TODO(fjhenigman): Figure out this failure.
	// Cube map skipped on 64-bit Windows with D3D FL 9.3
	ANGLE_SKIP_TEST_IF(GetParam() == ES2_D3D11_FL9_3());

	Main2D(&WebGLReadOutsideFramebufferTest::TestCopyTexSubImageCube, false);
	}

	// Check that copyTexImage2D sets (0,0,0,0) for pixels outside the framebuffer.
	TEST_P(WebGLReadOutsideFramebufferTest, CopyTexImage2D)
	{
	// http://anglebug.com/4092
	ANGLE_SKIP_TEST_IF(IsVulkan() \|\| IsD3D9() \|\| IsD3D11());
	Main2D(&WebGLReadOutsideFramebufferTest::TestCopyTexImage2D, true);

	// TODO(fjhenigman): Figure out this failure.
	// Cube map skipped on 64-bit Windows with D3D FL 9.3
	ANGLE_SKIP_TEST_IF(GetParam() == ES2_D3D11_FL9_3());

	Main2D(&WebGLReadOutsideFramebufferTest::TestCopyTexImageCube, true);
	}

	// Check that copyTexSubImage3D does not set a destination pixel when
	// the corresponding source pixel is outside the framebuffer.
	TEST_P(WebGL2ReadOutsideFramebufferTest, CopyTexSubImage3D)
	{
	// TODO(hqle): Metal doesn't implement 3D texture yet.
	// http://anglebug.com/4136 (ES2 renderer is mistakenly included in this test)
	ANGLE_SKIP_TEST_IF(IsMetal());
	// http://anglebug.com/4092
	ANGLE_SKIP_TEST_IF(IsVulkan() \|\| IsD3D9() \|\| IsD3D11());
	// Robust CopyTexSubImage3D behaviour is not implemented on OpenGL.
	ANGLE_SKIP_TEST_IF(IsDesktopOpenGL() \|\| IsOpenGLES());

	Main3D(&WebGLReadOutsideFramebufferTest::TestCopyTexSubImage3D, false);
	}

	ANGLE_INSTANTIATE_TEST_ES2_AND_ES3(WebGLReadOutsideFramebufferTest);

	ANGLE_INSTANTIATE_TEST_ES2_AND_ES3(WebGL2ReadOutsideFramebufferTest);

	} // namespace angle