BlitFramebufferANGLETest.cpp

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Commit
Author : Shahbaz Youssefi
Date : 2021-08-05 12:49:21
Hash : e70a1444
Message : Vulkan: Fix draw FBO1 followed by resolve FBO2 When syncing the framebuffer for blit/resolve, the render pass was not closed. This would be done later when necessary, except that onFramebufferChange called from FramebufferVk::syncState attempted to adjust the render area of the render pass (as it considered it open). If FBO2 is larger than FBO1, this would cause the render area of the previous render pass to become larger than the framebuffer size. This change makes sure that onFramebufferChange considers the render pass closed no matter what. Test is based on patch from steven@valvesoftware.com Bug: angleproject:6244 Change-Id: Iaec04232cfd2af04ba2564fd2de1dd5f08a40df6 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3076620 Reviewed-by: Tim Van Patten <timvp@google.com> Reviewed-by: Jamie Madill <jmadill@chromium.org> Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>
src/tests/gl_tests/BlitFramebufferANGLETest.cpp
//
// Copyright 2015 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.
//

#include "test_utils/ANGLETest.h"
#include "test_utils/gl_raii.h"

using namespace angle;

namespace
{
class BlitFramebufferANGLETest : public ANGLETest
{
  protected:
    BlitFramebufferANGLETest()
    {
        setWindowWidth(64);
        setWindowHeight(32);
        setConfigRedBits(8);
        setConfigGreenBits(8);
        setConfigBlueBits(8);
        setConfigAlphaBits(8);
        setConfigDepthBits(24);
        setConfigStencilBits(8);

        mCheckerProgram = 0;
        mBlueProgram    = 0;
        mRedProgram     = 0;

        mOriginalFBO = 0;

        mUserFBO                = 0;
        mUserColorBuffer        = 0;
        mUserDepthStencilBuffer = 0;

        mSmallFBO                = 0;
        mSmallColorBuffer        = 0;
        mSmallDepthStencilBuffer = 0;

        mColorOnlyFBO         = 0;
        mColorOnlyColorBuffer = 0;

        mDiffFormatFBO         = 0;
        mDiffFormatColorBuffer = 0;

        mDiffSizeFBO         = 0;
        mDiffSizeColorBuffer = 0;

        mMRTFBO          = 0;
        mMRTColorBuffer0 = 0;
        mMRTColorBuffer1 = 0;

        mRGBAColorbuffer              = 0;
        mRGBAFBO                      = 0;
        mRGBAMultisampledRenderbuffer = 0;
        mRGBAMultisampledFBO          = 0;

        mBGRAColorbuffer              = 0;
        mBGRAFBO                      = 0;
        mBGRAMultisampledRenderbuffer = 0;
        mBGRAMultisampledFBO          = 0;
    }

    void testSetUp() override
    {
        mCheckerProgram =
            CompileProgram(essl1_shaders::vs::Passthrough(), essl1_shaders::fs::Checkered());
        mBlueProgram = CompileProgram(essl1_shaders::vs::Simple(), essl1_shaders::fs::Blue());
        mRedProgram  = CompileProgram(essl1_shaders::vs::Simple(), essl1_shaders::fs::Red());
        if (mCheckerProgram == 0 || mBlueProgram == 0 || mRedProgram == 0)
        {
            FAIL() << "shader compilation failed.";
        }

        EXPECT_GL_NO_ERROR();

        GLint originalFBO;
        glGetIntegerv(GL_FRAMEBUFFER_BINDING, &originalFBO);
        if (originalFBO >= 0)
        {
            mOriginalFBO = (GLuint)originalFBO;
        }

        GLenum format = GL_RGBA;

        glGenFramebuffers(1, &mUserFBO);
        glBindFramebuffer(GL_FRAMEBUFFER, mUserFBO);
        glGenTextures(1, &mUserColorBuffer);
        glGenRenderbuffers(1, &mUserDepthStencilBuffer);
        glBindTexture(GL_TEXTURE_2D, mUserColorBuffer);
        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
                               mUserColorBuffer, 0);
        glTexImage2D(GL_TEXTURE_2D, 0, format, getWindowWidth(), getWindowHeight(), 0, format,
                     GL_UNSIGNED_BYTE, nullptr);
        glBindRenderbuffer(GL_RENDERBUFFER, mUserDepthStencilBuffer);
        glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8_OES, getWindowWidth(),
                              getWindowHeight());
        glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER,
                                  mUserDepthStencilBuffer);
        glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER,
                                  mUserDepthStencilBuffer);

        ASSERT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));
        ASSERT_GL_NO_ERROR();

        glGenFramebuffers(1, &mSmallFBO);
        glBindFramebuffer(GL_FRAMEBUFFER, mSmallFBO);
        glGenTextures(1, &mSmallColorBuffer);
        glGenRenderbuffers(1, &mSmallDepthStencilBuffer);
        glBindTexture(GL_TEXTURE_2D, mSmallColorBuffer);
        glTexImage2D(GL_TEXTURE_2D, 0, format, getWindowWidth() / 2, getWindowHeight() / 2, 0,
                     format, GL_UNSIGNED_BYTE, nullptr);
        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
                               mSmallColorBuffer, 0);
        glBindRenderbuffer(GL_RENDERBUFFER, mSmallDepthStencilBuffer);
        glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8_OES, getWindowWidth() / 2,
                              getWindowHeight() / 2);
        glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER,
                                  mSmallDepthStencilBuffer);
        glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER,
                                  mSmallDepthStencilBuffer);

        ASSERT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));
        ASSERT_GL_NO_ERROR();

        glGenFramebuffers(1, &mColorOnlyFBO);
        glBindFramebuffer(GL_FRAMEBUFFER, mColorOnlyFBO);
        glGenTextures(1, &mColorOnlyColorBuffer);
        glBindTexture(GL_TEXTURE_2D, mColorOnlyColorBuffer);
        glTexImage2D(GL_TEXTURE_2D, 0, format, getWindowWidth(), getWindowHeight(), 0, format,
                     GL_UNSIGNED_BYTE, nullptr);
        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
                               mColorOnlyColorBuffer, 0);

        ASSERT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));
        ASSERT_GL_NO_ERROR();

        glGenFramebuffers(1, &mDiffFormatFBO);
        glBindFramebuffer(GL_FRAMEBUFFER, mDiffFormatFBO);
        glGenTextures(1, &mDiffFormatColorBuffer);
        glBindTexture(GL_TEXTURE_2D, mDiffFormatColorBuffer);
        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, getWindowWidth(), getWindowHeight(), 0, GL_RGB,
                     GL_UNSIGNED_SHORT_5_6_5, nullptr);
        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
                               mDiffFormatColorBuffer, 0);

        ASSERT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));
        ASSERT_GL_NO_ERROR();

        glGenFramebuffers(1, &mDiffSizeFBO);
        glBindFramebuffer(GL_FRAMEBUFFER, mDiffSizeFBO);
        glGenTextures(1, &mDiffSizeColorBuffer);
        glBindTexture(GL_TEXTURE_2D, mDiffSizeColorBuffer);
        glTexImage2D(GL_TEXTURE_2D, 0, format, getWindowWidth() * 2, getWindowHeight() * 2, 0,
                     format, GL_UNSIGNED_BYTE, nullptr);
        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
                               mDiffSizeColorBuffer, 0);

        ASSERT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));
        ASSERT_GL_NO_ERROR();

        if (IsGLExtensionEnabled("GL_EXT_draw_buffers"))
        {
            glGenFramebuffers(1, &mMRTFBO);
            glBindFramebuffer(GL_FRAMEBUFFER, mMRTFBO);
            glGenTextures(1, &mMRTColorBuffer0);
            glGenTextures(1, &mMRTColorBuffer1);
            glBindTexture(GL_TEXTURE_2D, mMRTColorBuffer0);
            glTexImage2D(GL_TEXTURE_2D, 0, format, getWindowWidth(), getWindowHeight(), 0, format,
                         GL_UNSIGNED_BYTE, nullptr);
            glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_2D,
                                   mMRTColorBuffer0, 0);
            glBindTexture(GL_TEXTURE_2D, mMRTColorBuffer1);
            glTexImage2D(GL_TEXTURE_2D, 0, format, getWindowWidth(), getWindowHeight(), 0, format,
                         GL_UNSIGNED_BYTE, nullptr);
            glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT1_EXT, GL_TEXTURE_2D,
                                   mMRTColorBuffer1, 0);

            ASSERT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));
            ASSERT_GL_NO_ERROR();
        }

        if (IsGLExtensionEnabled("GL_ANGLE_framebuffer_multisample") &&
            IsGLExtensionEnabled("GL_OES_rgb8_rgba8"))
        {
            // RGBA single-sampled framebuffer
            glGenTextures(1, &mRGBAColorbuffer);
            glBindTexture(GL_TEXTURE_2D, mRGBAColorbuffer);
            glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, getWindowWidth(), getWindowHeight(), 0, GL_RGBA,
                         GL_UNSIGNED_BYTE, nullptr);

            glGenFramebuffers(1, &mRGBAFBO);
            glBindFramebuffer(GL_FRAMEBUFFER, mRGBAFBO);
            glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
                                   mRGBAColorbuffer, 0);

            ASSERT_GL_NO_ERROR();
            ASSERT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));

            // RGBA multisampled framebuffer
            glGenRenderbuffers(1, &mRGBAMultisampledRenderbuffer);
            glBindRenderbuffer(GL_RENDERBUFFER, mRGBAMultisampledRenderbuffer);
            glRenderbufferStorageMultisampleANGLE(GL_RENDERBUFFER, 1, GL_RGBA8, getWindowWidth(),
                                                  getWindowHeight());

            glGenFramebuffers(1, &mRGBAMultisampledFBO);
            glBindFramebuffer(GL_FRAMEBUFFER, mRGBAMultisampledFBO);
            glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER,
                                      mRGBAMultisampledRenderbuffer);

            ASSERT_GL_NO_ERROR();
            ASSERT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));

            if (IsGLExtensionEnabled("GL_EXT_texture_format_BGRA8888"))
            {
                // BGRA single-sampled framebuffer
                glGenTextures(1, &mBGRAColorbuffer);
                glBindTexture(GL_TEXTURE_2D, mBGRAColorbuffer);
                glTexImage2D(GL_TEXTURE_2D, 0, GL_BGRA_EXT, getWindowWidth(), getWindowHeight(), 0,
                             GL_BGRA_EXT, GL_UNSIGNED_BYTE, nullptr);

                glGenFramebuffers(1, &mBGRAFBO);
                glBindFramebuffer(GL_FRAMEBUFFER, mBGRAFBO);
                glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
                                       mBGRAColorbuffer, 0);

                ASSERT_GL_NO_ERROR();
                ASSERT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));

                // BGRA multisampled framebuffer
                glGenRenderbuffers(1, &mBGRAMultisampledRenderbuffer);
                glBindRenderbuffer(GL_RENDERBUFFER, mBGRAMultisampledRenderbuffer);
                glRenderbufferStorageMultisampleANGLE(GL_RENDERBUFFER, 1, GL_BGRA8_EXT,
                                                      getWindowWidth(), getWindowHeight());

                glGenFramebuffers(1, &mBGRAMultisampledFBO);
                glBindFramebuffer(GL_FRAMEBUFFER, mBGRAMultisampledFBO);
                glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER,
                                          mBGRAMultisampledRenderbuffer);

                ASSERT_GL_NO_ERROR();
                ASSERT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));
            }
        }

        glBindFramebuffer(GL_FRAMEBUFFER, mOriginalFBO);
    }

    void testTearDown() override
    {
        glDeleteProgram(mCheckerProgram);
        glDeleteProgram(mBlueProgram);
        glDeleteProgram(mRedProgram);

        glDeleteFramebuffers(1, &mUserFBO);
        glDeleteTextures(1, &mUserColorBuffer);
        glDeleteRenderbuffers(1, &mUserDepthStencilBuffer);

        glDeleteFramebuffers(1, &mSmallFBO);
        glDeleteTextures(1, &mSmallColorBuffer);
        glDeleteRenderbuffers(1, &mSmallDepthStencilBuffer);

        glDeleteFramebuffers(1, &mColorOnlyFBO);
        glDeleteTextures(1, &mSmallDepthStencilBuffer);

        glDeleteFramebuffers(1, &mDiffFormatFBO);
        glDeleteTextures(1, &mDiffFormatColorBuffer);

        glDeleteFramebuffers(1, &mDiffSizeFBO);
        glDeleteTextures(1, &mDiffSizeColorBuffer);

        if (IsGLExtensionEnabled("GL_EXT_draw_buffers"))
        {
            glDeleteFramebuffers(1, &mMRTFBO);
            glDeleteTextures(1, &mMRTColorBuffer0);
            glDeleteTextures(1, &mMRTColorBuffer1);
        }

        if (mRGBAColorbuffer != 0)
        {
            glDeleteTextures(1, &mRGBAColorbuffer);
        }

        if (mRGBAFBO != 0)
        {
            glDeleteFramebuffers(1, &mRGBAFBO);
        }

        if (mRGBAMultisampledRenderbuffer != 0)
        {
            glDeleteRenderbuffers(1, &mRGBAMultisampledRenderbuffer);
        }

        if (mRGBAMultisampledFBO != 0)
        {
            glDeleteFramebuffers(1, &mRGBAMultisampledFBO);
        }

        if (mBGRAColorbuffer != 0)
        {
            glDeleteTextures(1, &mBGRAColorbuffer);
        }

        if (mBGRAFBO != 0)
        {
            glDeleteFramebuffers(1, &mBGRAFBO);
        }

        if (mBGRAMultisampledRenderbuffer != 0)
        {
            glDeleteRenderbuffers(1, &mBGRAMultisampledRenderbuffer);
        }

        if (mBGRAMultisampledFBO != 0)
        {
            glDeleteFramebuffers(1, &mBGRAMultisampledFBO);
        }
    }

    void multisampleTestHelper(GLuint readFramebuffer, GLuint drawFramebuffer)
    {
        glClearColor(0.0, 1.0, 0.0, 1.0);
        glBindFramebuffer(GL_DRAW_FRAMEBUFFER, readFramebuffer);
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
        EXPECT_GL_NO_ERROR();

        glBindFramebuffer(GL_READ_FRAMEBUFFER, readFramebuffer);
        glBindFramebuffer(GL_DRAW_FRAMEBUFFER, drawFramebuffer);
        glBlitFramebufferANGLE(0, 0, getWindowWidth(), getWindowHeight(), 0, 0, getWindowWidth(),
                               getWindowHeight(), GL_COLOR_BUFFER_BIT, GL_NEAREST);
        EXPECT_GL_NO_ERROR();

        glBindFramebuffer(GL_READ_FRAMEBUFFER, drawFramebuffer);
        EXPECT_PIXEL_EQ(getWindowWidth() / 4, getWindowHeight() / 4, 0, 255, 0, 255);
        EXPECT_PIXEL_EQ(3 * getWindowWidth() / 4, getWindowHeight() / 4, 0, 255, 0, 255);
        EXPECT_PIXEL_EQ(3 * getWindowWidth() / 4, 3 * getWindowHeight() / 4, 0, 255, 0, 255);
        EXPECT_PIXEL_EQ(getWindowWidth() / 4, 3 * getWindowHeight() / 4, 0, 255, 0, 255);
    }

    bool checkExtension(const std::string &extension)
    {
        if (!IsGLExtensionEnabled(extension))
        {
            std::cout << "Test skipped because " << extension << " not supported." << std::endl;
            return false;
        }

        return true;
    }

    GLuint mCheckerProgram;
    GLuint mBlueProgram;
    GLuint mRedProgram;

    GLuint mOriginalFBO;

    GLuint mUserFBO;
    GLuint mUserColorBuffer;
    GLuint mUserDepthStencilBuffer;

    GLuint mSmallFBO;
    GLuint mSmallColorBuffer;
    GLuint mSmallDepthStencilBuffer;

    GLuint mColorOnlyFBO;
    GLuint mColorOnlyColorBuffer;

    GLuint mDiffFormatFBO;
    GLuint mDiffFormatColorBuffer;

    GLuint mDiffSizeFBO;
    GLuint mDiffSizeColorBuffer;

    GLuint mMRTFBO;
    GLuint mMRTColorBuffer0;
    GLuint mMRTColorBuffer1;

    GLuint mRGBAColorbuffer;
    GLuint mRGBAFBO;
    GLuint mRGBAMultisampledRenderbuffer;
    GLuint mRGBAMultisampledFBO;

    GLuint mBGRAColorbuffer;
    GLuint mBGRAFBO;
    GLuint mBGRAMultisampledRenderbuffer;
    GLuint mBGRAMultisampledFBO;
};

// Draw to user-created framebuffer, blit whole-buffer color to original framebuffer.
TEST_P(BlitFramebufferANGLETest, BlitColorToDefault)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    glBindFramebuffer(GL_FRAMEBUFFER, mUserFBO);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    drawQuad(mCheckerProgram, essl1_shaders::PositionAttrib(), 0.8f);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mUserFBO);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mOriginalFBO);

    glBlitFramebufferANGLE(0, 0, getWindowWidth(), getWindowHeight(), 0, 0, getWindowWidth(),
                           getWindowHeight(), GL_COLOR_BUFFER_BIT, GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, mOriginalFBO);

    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, getWindowHeight() / 4, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, getWindowHeight() / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::yellow);
}

// Blit color to/from default framebuffer with Flip-X/Flip-Y.
TEST_P(BlitFramebufferANGLETest, BlitColorWithFlip)
{
    // OpenGL ES 3.0 / GL_NV_framebuffer_blit required for flip.
    ANGLE_SKIP_TEST_IF(getClientMajorVersion() < 3 &&
                       !IsGLExtensionEnabled("GL_NV_framebuffer_blit"));

    glBindFramebuffer(GL_FRAMEBUFFER, mUserFBO);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    drawQuad(mCheckerProgram, essl1_shaders::PositionAttrib(), 0.8f);

    EXPECT_GL_NO_ERROR();

    // Blit to default with x-flip.
    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mUserFBO);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mOriginalFBO);

    glBlitFramebuffer(0, 0, getWindowWidth(), getWindowHeight(), getWindowWidth(), 0, 0,
                      getWindowHeight(), GL_COLOR_BUFFER_BIT, GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, mOriginalFBO);

    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, getWindowHeight() / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::yellow);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, getWindowHeight() / 4, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::green);

    // Blit to default with y-flip.
    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mUserFBO);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mOriginalFBO);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
    glBlitFramebuffer(0, 0, getWindowWidth(), getWindowHeight(), 0, getWindowHeight(),
                      getWindowWidth(), 0, GL_COLOR_BUFFER_BIT, GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, mOriginalFBO);

    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, getWindowHeight() / 4, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, getWindowHeight() / 4, GLColor::yellow);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::blue);

    // Blit from default with x-flip.

    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mOriginalFBO);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mUserFBO);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
    glBlitFramebuffer(0, 0, getWindowWidth(), getWindowHeight(), getWindowWidth(), 0, 0,
                      getWindowHeight(), GL_COLOR_BUFFER_BIT, GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mUserFBO);

    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, getWindowHeight() / 4, GLColor::yellow);
    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, getWindowHeight() / 4, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::red);

    // Blit from default with y-flip.
    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mOriginalFBO);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mUserFBO);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
    glBlitFramebuffer(0, 0, getWindowWidth(), getWindowHeight(), 0, getWindowHeight(),
                      getWindowWidth(), 0, GL_COLOR_BUFFER_BIT, GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, mUserFBO);

    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, getWindowHeight() / 4, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, getWindowHeight() / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::yellow);
}

// Draw to system framebuffer, blit whole-buffer color to user-created framebuffer.
TEST_P(BlitFramebufferANGLETest, ReverseColorBlit)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    // TODO(jmadill): Fix this. http://anglebug.com/2743
    ANGLE_SKIP_TEST_IF(IsVulkan() && IsAndroid());

    glBindFramebuffer(GL_FRAMEBUFFER, mOriginalFBO);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    drawQuad(mCheckerProgram, essl1_shaders::PositionAttrib(), 0.8f);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mOriginalFBO);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mUserFBO);

    glBlitFramebufferANGLE(0, 0, getWindowWidth(), getWindowHeight(), 0, 0, getWindowWidth(),
                           getWindowHeight(), GL_COLOR_BUFFER_BIT, GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, mUserFBO);

    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, getWindowHeight() / 4, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, getWindowHeight() / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::yellow);
}

// blit from user-created FBO to system framebuffer, with the scissor test enabled.
TEST_P(BlitFramebufferANGLETest, ScissoredBlit)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    glBindFramebuffer(GL_FRAMEBUFFER, mUserFBO);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    drawQuad(mCheckerProgram, essl1_shaders::PositionAttrib(), 0.8f);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mOriginalFBO);
    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mUserFBO);

    glClearColor(1.0, 1.0, 1.0, 1.0);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    glScissor(getWindowWidth() / 2, 0, getWindowWidth() / 2, getWindowHeight());
    glEnable(GL_SCISSOR_TEST);

    glBlitFramebufferANGLE(0, 0, getWindowWidth(), getWindowHeight(), 0, 0, getWindowWidth(),
                           getWindowHeight(), GL_COLOR_BUFFER_BIT, GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glDisable(GL_SCISSOR_TEST);

    glBindFramebuffer(GL_FRAMEBUFFER, mOriginalFBO);

    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, getWindowHeight() / 4, GLColor::white);
    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::white);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, getWindowHeight() / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::yellow);
}

// blit from system FBO to user-created framebuffer, with the scissor test enabled.
TEST_P(BlitFramebufferANGLETest, ReverseScissoredBlit)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    glBindFramebuffer(GL_FRAMEBUFFER, mOriginalFBO);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    drawQuad(mCheckerProgram, essl1_shaders::PositionAttrib(), 0.8f);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mUserFBO);
    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mOriginalFBO);

    glClearColor(1.0, 1.0, 1.0, 1.0);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    glScissor(getWindowWidth() / 2, 0, getWindowWidth() / 2, getWindowHeight());
    glEnable(GL_SCISSOR_TEST);

    glBlitFramebufferANGLE(0, 0, getWindowWidth(), getWindowHeight(), 0, 0, getWindowWidth(),
                           getWindowHeight(), GL_COLOR_BUFFER_BIT, GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glDisable(GL_SCISSOR_TEST);

    glBindFramebuffer(GL_FRAMEBUFFER, mUserFBO);

    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, getWindowHeight() / 4, GLColor::white);
    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::white);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, getWindowHeight() / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::yellow);
}

// blit from user-created FBO to system framebuffer, using region larger than buffer.
TEST_P(BlitFramebufferANGLETest, OversizedBlit)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    glBindFramebuffer(GL_FRAMEBUFFER, mUserFBO);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    drawQuad(mCheckerProgram, essl1_shaders::PositionAttrib(), 0.8f);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mOriginalFBO);
    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mUserFBO);

    glClearColor(1.0, 1.0, 1.0, 1.0);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    glBlitFramebufferANGLE(0, 0, getWindowWidth() * 2, getWindowHeight() * 2, 0, 0,
                           getWindowWidth() * 2, getWindowHeight() * 2, GL_COLOR_BUFFER_BIT,
                           GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, mOriginalFBO);

    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, getWindowHeight() / 4, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, getWindowHeight() / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::yellow);
}

// blit from system FBO to user-created framebuffer, using region larger than buffer.
TEST_P(BlitFramebufferANGLETest, ReverseOversizedBlit)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    glBindFramebuffer(GL_FRAMEBUFFER, mOriginalFBO);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    drawQuad(mCheckerProgram, essl1_shaders::PositionAttrib(), 0.8f);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mUserFBO);
    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mOriginalFBO);

    glClearColor(1.0, 1.0, 1.0, 1.0);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    glBlitFramebufferANGLE(0, 0, getWindowWidth() * 2, getWindowHeight() * 2, 0, 0,
                           getWindowWidth() * 2, getWindowHeight() * 2, GL_COLOR_BUFFER_BIT,
                           GL_NEAREST);
    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, mUserFBO);

    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, getWindowHeight() / 4, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, getWindowHeight() / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::yellow);
}

// blit from user-created FBO to system framebuffer, with depth buffer.
TEST_P(BlitFramebufferANGLETest, BlitWithDepthUserToDefault)
{
    // TODO(http://anglebug.com/6154): glBlitFramebufferANGLE() generates GL_INVALID_OPERATION for
    // the ES2_OpenGL backend.
    ANGLE_SKIP_TEST_IF(IsLinux() && IsIntel() && IsOpenGL());

    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    glBindFramebuffer(GL_FRAMEBUFFER, mUserFBO);

    glDepthMask(GL_TRUE);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    glEnable(GL_DEPTH_TEST);

    EXPECT_GL_NO_ERROR();

    // Clear the first half of the screen
    glEnable(GL_SCISSOR_TEST);
    glScissor(0, 0, getWindowWidth(), getWindowHeight() / 2);

    glClearDepthf(0.1f);
    glClearColor(1.0, 0.0, 0.0, 1.0);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    // Scissor the second half of the screen
    glScissor(0, getWindowHeight() / 2, getWindowWidth(), getWindowHeight() / 2);

    glClearDepthf(0.9f);
    glClearColor(0.0, 1.0, 0.0, 1.0);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glDisable(GL_SCISSOR_TEST);

    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mOriginalFBO);
    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mUserFBO);

    glBlitFramebufferANGLE(0, 0, getWindowWidth(), getWindowHeight(), 0, 0, getWindowWidth(),
                           getWindowHeight(), GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT,
                           GL_NEAREST);
    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, mOriginalFBO);

    // if blit is happening correctly, this quad will draw only on the bottom half since it will
    // be behind on the first half and in front on the second half.
    drawQuad(mBlueProgram, essl1_shaders::PositionAttrib(), 0.5f);

    glDisable(GL_DEPTH_TEST);

    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, getWindowHeight() / 4, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, getWindowHeight() / 4, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::blue);
}

// blit from system FBO to user-created framebuffer, with depth buffer.
TEST_P(BlitFramebufferANGLETest, BlitWithDepthDefaultToUser)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    glBindFramebuffer(GL_FRAMEBUFFER, mOriginalFBO);

    glDepthMask(GL_TRUE);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    glEnable(GL_DEPTH_TEST);

    EXPECT_GL_NO_ERROR();

    // Clear the first half of the screen
    glEnable(GL_SCISSOR_TEST);
    glScissor(0, 0, getWindowWidth(), getWindowHeight() / 2);

    glClearDepthf(0.1f);
    glClearColor(1.0, 0.0, 0.0, 1.0);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    // Scissor the second half of the screen
    glScissor(0, getWindowHeight() / 2, getWindowWidth(), getWindowHeight() / 2);

    glClearDepthf(0.9f);
    glClearColor(0.0, 1.0, 0.0, 1.0);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glDisable(GL_SCISSOR_TEST);

    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mUserFBO);
    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mOriginalFBO);

    glBlitFramebufferANGLE(0, 0, getWindowWidth(), getWindowHeight(), 0, 0, getWindowWidth(),
                           getWindowHeight(), GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT,
                           GL_NEAREST);
    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, mUserFBO);

    // if blit is happening correctly, this quad will draw only on the bottom half since it will be
    // behind on the first half and in front on the second half.
    drawQuad(mBlueProgram, essl1_shaders::PositionAttrib(), 0.5f);

    glDisable(GL_DEPTH_TEST);

    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, getWindowHeight() / 4, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, getWindowHeight() / 4, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::blue);
}

// blit from one region of the system fbo to another-- this should fail.
TEST_P(BlitFramebufferANGLETest, BlitSameBufferOriginal)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    glBindFramebuffer(GL_FRAMEBUFFER, mOriginalFBO);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    drawQuad(mCheckerProgram, essl1_shaders::PositionAttrib(), 0.3f);

    EXPECT_GL_NO_ERROR();

    glBlitFramebufferANGLE(0, 0, getWindowWidth() / 2, getWindowHeight(), getWindowWidth() / 2, 0,
                           getWindowWidth(), getWindowHeight(), GL_COLOR_BUFFER_BIT, GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_OPERATION);
}

// blit from one region of the system fbo to another.
TEST_P(BlitFramebufferANGLETest, BlitSameBufferUser)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    glBindFramebuffer(GL_FRAMEBUFFER, mUserFBO);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    drawQuad(mCheckerProgram, essl1_shaders::PositionAttrib(), 0.3f);

    EXPECT_GL_NO_ERROR();

    glBlitFramebufferANGLE(0, 0, getWindowWidth() / 2, getWindowHeight(), getWindowWidth() / 2, 0,
                           getWindowWidth(), getWindowHeight(), GL_COLOR_BUFFER_BIT, GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_OPERATION);
}

TEST_P(BlitFramebufferANGLETest, BlitPartialColor)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    glBindFramebuffer(GL_FRAMEBUFFER, mUserFBO);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    drawQuad(mCheckerProgram, essl1_shaders::PositionAttrib(), 0.5f);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mOriginalFBO);
    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mUserFBO);

    glClearColor(1.0, 1.0, 1.0, 1.0);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    glBlitFramebufferANGLE(0, 0, getWindowWidth() / 2, getWindowHeight() / 2, 0,
                           getWindowHeight() / 2, getWindowWidth() / 2, getWindowHeight(),
                           GL_COLOR_BUFFER_BIT, GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, mOriginalFBO);

    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, getWindowHeight() / 4, GLColor::white);
    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, getWindowHeight() / 4, GLColor::white);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::white);
}

TEST_P(BlitFramebufferANGLETest, BlitDifferentSizes)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    glBindFramebuffer(GL_FRAMEBUFFER, mUserFBO);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    drawQuad(mCheckerProgram, essl1_shaders::PositionAttrib(), 0.5f);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mSmallFBO);
    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mUserFBO);

    glClearColor(1.0, 1.0, 1.0, 1.0);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    glBlitFramebufferANGLE(0, 0, getWindowWidth(), getWindowHeight(), 0, 0, getWindowWidth(),
                           getWindowHeight(), GL_COLOR_BUFFER_BIT, GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, mSmallFBO);

    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, getWindowHeight() / 4, GLColor::red);

    EXPECT_GL_NO_ERROR();
}

TEST_P(BlitFramebufferANGLETest, BlitWithMissingAttachments)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    glBindFramebuffer(GL_FRAMEBUFFER, mColorOnlyFBO);

    glClear(GL_COLOR_BUFFER_BIT);
    drawQuad(mCheckerProgram, essl1_shaders::PositionAttrib(), 0.3f);

    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mOriginalFBO);
    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mColorOnlyFBO);

    glClearColor(1.0, 1.0, 1.0, 1.0);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    // generate INVALID_OPERATION if the read FBO has no depth attachment
    glBlitFramebufferANGLE(0, 0, getWindowWidth(), getWindowHeight(), 0, 0, getWindowWidth(),
                           getWindowHeight(), GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT,
                           GL_NEAREST);

    EXPECT_GL_ERROR(GL_INVALID_OPERATION);

    // generate INVALID_OPERATION if the read FBO has no stencil attachment
    glBlitFramebufferANGLE(0, 0, getWindowWidth(), getWindowHeight(), 0, 0, getWindowWidth(),
                           getWindowHeight(), GL_COLOR_BUFFER_BIT | GL_STENCIL_BUFFER_BIT,
                           GL_NEAREST);

    EXPECT_GL_ERROR(GL_INVALID_OPERATION);

    // generate INVALID_OPERATION if we read from a missing color attachment
    glReadBuffer(GL_COLOR_ATTACHMENT1);
    glBlitFramebufferANGLE(0, 0, getWindowWidth(), getWindowHeight(), 0, 0, getWindowWidth(),
                           getWindowHeight(), GL_COLOR_BUFFER_BIT, GL_NEAREST);

    EXPECT_GL_ERROR(GL_INVALID_OPERATION);
}

TEST_P(BlitFramebufferANGLETest, BlitStencil)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    // http://anglebug.com/2205
    ANGLE_SKIP_TEST_IF(IsIntel() && IsD3D9());

    // http://anglebug.com/4919
    ANGLE_SKIP_TEST_IF(IsIntel() && IsMetal());

    // http://anglebug.com/5396
    ANGLE_SKIP_TEST_IF(IsAMD() && IsD3D9());

    glBindFramebuffer(GL_FRAMEBUFFER, mUserFBO);

    glClearColor(0.0, 1.0, 0.0, 1.0);
    glClearStencil(0x0);
    glClear(GL_COLOR_BUFFER_BIT | GL_STENCIL_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    // Scissor half the screen so we fill the stencil only halfway
    glScissor(0, 0, getWindowWidth(), getWindowHeight() / 2);
    glEnable(GL_SCISSOR_TEST);

    // fill the stencil buffer with 0x1
    glStencilFunc(GL_ALWAYS, 0x1, 0xFF);
    glStencilOp(GL_REPLACE, GL_REPLACE, GL_REPLACE);
    glEnable(GL_STENCIL_TEST);
    drawQuad(mRedProgram, essl1_shaders::PositionAttrib(), 0.3f);

    glDisable(GL_SCISSOR_TEST);

    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mOriginalFBO);
    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mUserFBO);

    // These clears are not useful in theory because we're copying over them, but its
    // helpful in debugging if we see white in any result.
    glClearColor(1.0, 1.0, 1.0, 1.0);
    glClearStencil(0x0);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    // depth blit request should be silently ignored, because the read FBO has no depth attachment
    glBlitFramebufferANGLE(0, 0, getWindowWidth(), getWindowHeight(), 0, 0, getWindowWidth(),
                           getWindowHeight(), GL_COLOR_BUFFER_BIT | GL_STENCIL_BUFFER_BIT,
                           GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, mOriginalFBO);

    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, getWindowHeight() / 4, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, getWindowHeight() / 4, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::green);

    glStencilFunc(GL_EQUAL, 0x1, 0xFF);  // only pass if stencil buffer at pixel reads 0x1

    drawQuad(mBlueProgram, essl1_shaders::PositionAttrib(),
             0.8f);  // blue quad will draw if stencil buffer was copied

    glDisable(GL_STENCIL_TEST);

    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, getWindowHeight() / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, getWindowHeight() / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::green);
}

// make sure that attempting to blit a partial depth buffer issues an error
TEST_P(BlitFramebufferANGLETest, BlitPartialDepthStencil)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    glBindFramebuffer(GL_FRAMEBUFFER, mUserFBO);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    drawQuad(mCheckerProgram, essl1_shaders::PositionAttrib(), 0.5f);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mOriginalFBO);
    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mUserFBO);

    glBlitFramebufferANGLE(0, 0, getWindowWidth() / 2, getWindowHeight() / 2, 0, 0,
                           getWindowWidth() / 2, getWindowHeight() / 2, GL_DEPTH_BUFFER_BIT,
                           GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_OPERATION);
}

// Test blit with MRT framebuffers
TEST_P(BlitFramebufferANGLETest, BlitMRT)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    if (!IsGLExtensionEnabled("GL_EXT_draw_buffers"))
    {
        return;
    }

    GLenum drawBuffers[] = {GL_COLOR_ATTACHMENT0_EXT, GL_COLOR_ATTACHMENT1_EXT};

    glBindFramebuffer(GL_FRAMEBUFFER, mMRTFBO);
    glDrawBuffersEXT(2, drawBuffers);

    glBindFramebuffer(GL_FRAMEBUFFER, mColorOnlyFBO);

    glClear(GL_COLOR_BUFFER_BIT);

    drawQuad(mCheckerProgram, essl1_shaders::PositionAttrib(), 0.8f);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mColorOnlyFBO);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mMRTFBO);

    glBlitFramebufferANGLE(0, 0, getWindowWidth(), getWindowHeight(), 0, 0, getWindowWidth(),
                           getWindowHeight(), GL_COLOR_BUFFER_BIT, GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, mMRTFBO);

    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, getWindowHeight() / 4, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, getWindowHeight() / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::yellow);

    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT1_EXT, GL_TEXTURE_2D, 0, 0);
    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, mMRTColorBuffer0,
                           0);

    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, getWindowHeight() / 4, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, getWindowHeight() / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * getWindowWidth() / 4, 3 * getWindowHeight() / 4, GLColor::yellow);

    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, mMRTColorBuffer0,
                           0);
    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT1_EXT, GL_TEXTURE_2D,
                           mMRTColorBuffer1, 0);
}

// Test multisampled framebuffer blits if supported
TEST_P(BlitFramebufferANGLETest, MultisampledRGBAToRGBA)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    if (!checkExtension("GL_ANGLE_framebuffer_multisample"))
        return;

    if (!checkExtension("GL_OES_rgb8_rgba8"))
        return;

    multisampleTestHelper(mRGBAMultisampledFBO, mRGBAFBO);
}

TEST_P(BlitFramebufferANGLETest, MultisampledRGBAToBGRA)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    // VVL report error http://anglebug.com/4694
    ANGLE_SKIP_TEST_IF(IsVulkan());

    if (!checkExtension("GL_ANGLE_framebuffer_multisample"))
        return;

    if (!checkExtension("GL_OES_rgb8_rgba8"))
        return;

    if (!checkExtension("GL_EXT_texture_format_BGRA8888"))
        return;

    multisampleTestHelper(mRGBAMultisampledFBO, mBGRAFBO);
}

TEST_P(BlitFramebufferANGLETest, MultisampledBGRAToRGBA)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    // VVL report error http://anglebug.com/4694
    ANGLE_SKIP_TEST_IF(IsVulkan());

    if (!checkExtension("GL_ANGLE_framebuffer_multisample"))
        return;

    if (!checkExtension("GL_OES_rgb8_rgba8"))
        return;

    if (!checkExtension("GL_EXT_texture_format_BGRA8888"))
        return;

    multisampleTestHelper(mBGRAMultisampledFBO, mRGBAFBO);
}

TEST_P(BlitFramebufferANGLETest, MultisampledBGRAToBGRA)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    if (!checkExtension("GL_ANGLE_framebuffer_multisample"))
        return;

    if (!checkExtension("GL_OES_rgb8_rgba8"))
        return;

    if (!checkExtension("GL_EXT_texture_format_BGRA8888"))
        return;

    multisampleTestHelper(mBGRAMultisampledFBO, mBGRAFBO);
}

// Make sure that attempts to stretch in a blit call issue an error
TEST_P(BlitFramebufferANGLETest, ErrorStretching)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    glBindFramebuffer(GL_FRAMEBUFFER, mUserFBO);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    drawQuad(mCheckerProgram, essl1_shaders::PositionAttrib(), 0.5f);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mOriginalFBO);
    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mUserFBO);

    glBlitFramebufferANGLE(0, 0, getWindowWidth() / 2, getWindowHeight() / 2, 0, 0,
                           getWindowWidth(), getWindowHeight(), GL_COLOR_BUFFER_BIT, GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_OPERATION);
}

// Make sure that attempts to flip in a blit call issue an error
TEST_P(BlitFramebufferANGLETest, ErrorFlipping)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    glBindFramebuffer(GL_FRAMEBUFFER, mUserFBO);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    drawQuad(mCheckerProgram, essl1_shaders::PositionAttrib(), 0.5f);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mOriginalFBO);
    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mUserFBO);

    glBlitFramebufferANGLE(0, 0, getWindowWidth() / 2, getWindowHeight() / 2, getWindowWidth() / 2,
                           getWindowHeight() / 2, 0, 0, GL_COLOR_BUFFER_BIT, GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_OPERATION);
}

TEST_P(BlitFramebufferANGLETest, Errors)
{
    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_ANGLE_framebuffer_blit"));

    glBindFramebuffer(GL_FRAMEBUFFER, mUserFBO);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    drawQuad(mCheckerProgram, essl1_shaders::PositionAttrib(), 0.5f);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mOriginalFBO);
    glBindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, mUserFBO);

    glBlitFramebufferANGLE(0, 0, getWindowWidth(), getWindowHeight(), 0, 0, getWindowWidth(),
                           getWindowHeight(), GL_COLOR_BUFFER_BIT, GL_LINEAR);
    EXPECT_GL_ERROR(GL_INVALID_ENUM);

    glBlitFramebufferANGLE(0, 0, getWindowWidth(), getWindowHeight(), 0, 0, getWindowWidth(),
                           getWindowHeight(), GL_COLOR_BUFFER_BIT | 234, GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_VALUE);

    glBindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, mDiffFormatFBO);

    glBlitFramebufferANGLE(0, 0, getWindowWidth(), getWindowHeight(), 0, 0, getWindowWidth(),
                           getWindowHeight(), GL_COLOR_BUFFER_BIT, GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_OPERATION);
}

// TODO(geofflang): Fix the dependence on glBlitFramebufferANGLE without checks and assuming the
// default framebuffer is BGRA to enable the GL and GLES backends. (http://anglebug.com/1289)

class BlitFramebufferTest : public ANGLETest
{
  protected:
    BlitFramebufferTest()
    {
        setWindowWidth(256);
        setWindowHeight(256);
        setConfigRedBits(8);
        setConfigGreenBits(8);
        setConfigBlueBits(8);
        setConfigAlphaBits(8);
        setConfigDepthBits(24);
        setConfigStencilBits(8);
    }

    void initColorFBO(GLFramebuffer *fbo,
                      GLRenderbuffer *rbo,
                      GLenum rboFormat,
                      GLsizei width,
                      GLsizei height)
    {
        glBindRenderbuffer(GL_RENDERBUFFER, *rbo);
        glRenderbufferStorage(GL_RENDERBUFFER, rboFormat, width, height);

        glBindFramebuffer(GL_FRAMEBUFFER, *fbo);
        glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER, *rbo);
    }

    void initColorFBOWithCheckerPattern(GLFramebuffer *fbo,
                                        GLRenderbuffer *rbo,
                                        GLenum rboFormat,
                                        GLsizei width,
                                        GLsizei height)
    {
        initColorFBO(fbo, rbo, rboFormat, width, height);

        ANGLE_GL_PROGRAM(checkerProgram, essl1_shaders::vs::Passthrough(),
                         essl1_shaders::fs::Checkered());
        glViewport(0, 0, width, height);
        glBindFramebuffer(GL_FRAMEBUFFER, *fbo);
        drawQuad(checkerProgram.get(), essl1_shaders::PositionAttrib(), 0.5f);
    }
};

class BlitFramebufferTestES31 : public BlitFramebufferTest
{};

// Tests resolving a multisample depth buffer.
TEST_P(BlitFramebufferTest, MultisampleDepth)
{
    // Test failure introduced by Apple's changes (anglebug.com/5505)
    ANGLE_SKIP_TEST_IF(IsMetal());

    // TODO(oetuaho@nvidia.com): http://crbug.com/837717
    ANGLE_SKIP_TEST_IF(IsOpenGL() && IsOSX());

    GLRenderbuffer renderbuf;
    glBindRenderbuffer(GL_RENDERBUFFER, renderbuf.get());
    glRenderbufferStorageMultisample(GL_RENDERBUFFER, 2, GL_DEPTH_COMPONENT24, 256, 256);

    GLFramebuffer framebuffer;
    glBindFramebuffer(GL_FRAMEBUFFER, framebuffer.get());
    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER,
                              renderbuf.get());

    ASSERT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));

    glClearDepthf(0.5f);
    glClear(GL_DEPTH_BUFFER_BIT);

    GLRenderbuffer destRenderbuf;
    glBindRenderbuffer(GL_RENDERBUFFER, destRenderbuf.get());
    glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT24, 256, 256);

    GLFramebuffer resolved;
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, resolved.get());
    glFramebufferRenderbuffer(GL_DRAW_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER,
                              destRenderbuf.get());

    glBindFramebuffer(GL_READ_FRAMEBUFFER, framebuffer.get());
    glBlitFramebuffer(0, 0, 256, 256, 0, 0, 256, 256, GL_DEPTH_BUFFER_BIT, GL_NEAREST);

    glBindFramebuffer(GL_FRAMEBUFFER, resolved.get());

    GLTexture colorbuf;
    glBindTexture(GL_TEXTURE_2D, colorbuf.get());
    glTexStorage2D(GL_TEXTURE_2D, 1, GL_RGBA8, 256, 256);
    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, colorbuf.get(), 0);

    ASSERT_GL_NO_ERROR();

    // Clear to green
    glClearColor(0.0f, 1.0f, 0.0f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT);
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::green);

    // Make sure resulting depth is near 0.5f.
    ANGLE_GL_PROGRAM(drawRed, essl3_shaders::vs::Simple(), essl3_shaders::fs::Red());
    glEnable(GL_DEPTH_TEST);
    glDepthMask(false);
    glDepthFunc(GL_LESS);
    drawQuad(drawRed.get(), essl3_shaders::PositionAttrib(), -0.01f);
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(255, 0, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(0, 255, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(255, 255, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(127, 127, GLColor::red);

    ANGLE_GL_PROGRAM(drawBlue, essl3_shaders::vs::Simple(), essl3_shaders::fs::Blue());
    glEnable(GL_DEPTH_TEST);
    glDepthMask(false);
    glDepthFunc(GL_GREATER);
    drawQuad(drawBlue.get(), essl3_shaders::PositionAttrib(), 0.01f);
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(255, 0, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(0, 255, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(255, 255, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(127, 127, GLColor::blue);

    ASSERT_GL_NO_ERROR();
}

// Blit multisample stencil buffer to default framebuffer without prerotaion.
TEST_P(BlitFramebufferTest, BlitMultisampleStencilToDefault)
{
    // http://anglebug.com/3496
    ANGLE_SKIP_TEST_IF(IsOpenGL() && IsIntel() && IsOSX());

    // http://anglebug.com/5106
    ANGLE_SKIP_TEST_IF(IsMetal() && IsIntel() && IsOSX());

    glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

    GLRenderbuffer colorbuf;
    glBindRenderbuffer(GL_RENDERBUFFER, colorbuf.get());
    glRenderbufferStorageMultisample(GL_RENDERBUFFER, 4, GL_RGBA8, 128, 128);

    GLRenderbuffer depthstencilbuf;
    glBindRenderbuffer(GL_RENDERBUFFER, depthstencilbuf.get());
    glRenderbufferStorageMultisample(GL_RENDERBUFFER, 4, GL_DEPTH24_STENCIL8, 128, 128);

    GLFramebuffer framebuffer;
    glBindFramebuffer(GL_FRAMEBUFFER, framebuffer.get());
    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER, colorbuf);
    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER,
                              depthstencilbuf);
    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER,
                              depthstencilbuf);
    glCheckFramebufferStatus(GL_FRAMEBUFFER);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
    glFlush();

    // Replace stencil to 1.
    ANGLE_GL_PROGRAM(drawRed, essl3_shaders::vs::Simple(), essl3_shaders::fs::Red());
    glEnable(GL_STENCIL_TEST);
    glStencilOp(GL_REPLACE, GL_REPLACE, GL_REPLACE);
    glStencilFunc(GL_ALWAYS, 1, 255);
    drawQuad(drawRed.get(), essl3_shaders::PositionAttrib(), 0.8f);

    // Blit multisample stencil buffer to default frambuffer.
    GLenum attachments1[] = {GL_COLOR_ATTACHMENT0};
    glInvalidateFramebuffer(GL_FRAMEBUFFER, 1, attachments1);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
    glBlitFramebuffer(0, 0, 128, 128, 0, 0, 128, 128, GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT,
                      GL_NEAREST);
    glBindFramebuffer(GL_READ_FRAMEBUFFER, 0);

    // Disable stencil and draw full_screen green color.
    ANGLE_GL_PROGRAM(drawGreen, essl3_shaders::vs::Simple(), essl3_shaders::fs::Green());
    glDisable(GL_STENCIL_TEST);
    drawQuad(drawGreen.get(), essl3_shaders::PositionAttrib(), 0.5f);

    // Draw blue color if the stencil is equal to 1.
    // If the blit finished successfully, the stencil test should all pass.
    ANGLE_GL_PROGRAM(drawBlue, essl3_shaders::vs::Simple(), essl3_shaders::fs::Blue());
    glEnable(GL_STENCIL_TEST);
    glStencilFunc(GL_EQUAL, 1, 255);
    drawQuad(drawBlue.get(), essl3_shaders::PositionAttrib(), 0.2f);

    // Check the result, especially the boundaries.
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(127, 0, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(50, 0, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(127, 1, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(0, 127, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(127, 127, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(64, 64, GLColor::blue);

    ASSERT_GL_NO_ERROR();
}

// Tests clearing a multisampled depth buffer.
TEST_P(BlitFramebufferTest, MultisampleDepthClear)
{
    // clearDepth && !maskDepth fails on Intel Ubuntu 19.04 Mesa 19.0.2 GL. http://anglebug.com/3614
    ANGLE_SKIP_TEST_IF(IsLinux() && IsIntel() && IsDesktopOpenGL());

    // http://anglebug.com/4092
    ANGLE_SKIP_TEST_IF(IsAndroid() && IsOpenGLES());

    GLRenderbuffer depthMS;
    glBindRenderbuffer(GL_RENDERBUFFER, depthMS.get());
    glRenderbufferStorageMultisample(GL_RENDERBUFFER, 2, GL_DEPTH_COMPONENT24, 256, 256);

    GLRenderbuffer colorMS;
    glBindRenderbuffer(GL_RENDERBUFFER, colorMS.get());
    glRenderbufferStorageMultisample(GL_RENDERBUFFER, 2, GL_RGBA8, 256, 256);

    GLRenderbuffer colorResolved;
    glBindRenderbuffer(GL_RENDERBUFFER, colorResolved.get());
    glRenderbufferStorage(GL_RENDERBUFFER, GL_RGBA8, 256, 256);

    GLFramebuffer framebufferMS;
    glBindFramebuffer(GL_FRAMEBUFFER, framebufferMS.get());
    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, depthMS.get());
    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER, colorMS.get());

    // Clear depth buffer to 0.5 and color to green.
    glClearDepthf(0.5f);
    glClearColor(0.0f, 1.0f, 0.0f, 1.0f);
    glClear(GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT);

    glFlush();

    // Draw red into the multisampled color buffer.
    ANGLE_GL_PROGRAM(drawRed, essl3_shaders::vs::Simple(), essl3_shaders::fs::Red());
    glEnable(GL_DEPTH_TEST);
    glDepthFunc(GL_EQUAL);
    drawQuad(drawRed.get(), essl3_shaders::PositionAttrib(), 0.0f);

    // Resolve the color buffer to make sure the above draw worked correctly, which in turn implies
    // that the multisampled depth clear worked.
    GLFramebuffer framebufferResolved;
    glBindFramebuffer(GL_FRAMEBUFFER, framebufferResolved.get());
    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER,
                              colorResolved.get());
    glBindFramebuffer(GL_READ_FRAMEBUFFER, framebufferMS.get());
    glBlitFramebuffer(0, 0, 256, 256, 0, 0, 256, 256, GL_COLOR_BUFFER_BIT, GL_NEAREST);

    glBindFramebuffer(GL_FRAMEBUFFER, framebufferResolved.get());

    ASSERT_GL_NO_ERROR();

    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(255, 0, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(0, 255, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(255, 255, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(127, 127, GLColor::red);

    ASSERT_GL_NO_ERROR();
}

// Test resolving a multisampled stencil buffer.
TEST_P(BlitFramebufferTest, MultisampleStencil)
{
    // Incorrect rendering results seen on AMD Windows OpenGL. http://anglebug.com/2486
    ANGLE_SKIP_TEST_IF(IsAMD() && IsOpenGL() && IsWindows());

    // http://anglebug.com/5106
    ANGLE_SKIP_TEST_IF(IsMetal() && IsIntel() && IsOSX());

    GLRenderbuffer renderbuf;
    glBindRenderbuffer(GL_RENDERBUFFER, renderbuf.get());
    glRenderbufferStorageMultisample(GL_RENDERBUFFER, 2, GL_STENCIL_INDEX8, 256, 256);

    ANGLE_GL_PROGRAM(drawRed, essl3_shaders::vs::Simple(), essl3_shaders::fs::Red());

    GLFramebuffer framebuffer;
    glBindFramebuffer(GL_FRAMEBUFFER, framebuffer.get());
    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER,
                              renderbuf.get());

    ASSERT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));

    // fill the stencil buffer with 0x1
    glStencilFunc(GL_ALWAYS, 0x1, 0xFF);
    glStencilOp(GL_REPLACE, GL_REPLACE, GL_REPLACE);
    glEnable(GL_STENCIL_TEST);
    drawQuad(drawRed.get(), essl3_shaders::PositionAttrib(), 0.5f);

    GLTexture destColorbuf;
    glBindTexture(GL_TEXTURE_2D, destColorbuf.get());
    glTexStorage2D(GL_TEXTURE_2D, 1, GL_RGBA8, 256, 256);

    GLRenderbuffer destRenderbuf;
    glBindRenderbuffer(GL_RENDERBUFFER, destRenderbuf.get());
    glRenderbufferStorage(GL_RENDERBUFFER, GL_STENCIL_INDEX8, 256, 256);

    GLFramebuffer resolved;
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, resolved.get());
    glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
                           destColorbuf.get(), 0);
    glFramebufferRenderbuffer(GL_DRAW_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER,
                              destRenderbuf.get());

    glBindFramebuffer(GL_READ_FRAMEBUFFER, framebuffer.get());
    glBlitFramebuffer(0, 0, 256, 256, 0, 0, 256, 256, GL_STENCIL_BUFFER_BIT, GL_NEAREST);

    glBindFramebuffer(GL_FRAMEBUFFER, resolved.get());

    ASSERT_GL_NO_ERROR();

    // Clear to green
    glClearColor(0.0f, 1.0f, 0.0f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT);
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::green);

    // Draw red if the stencil is 0x1, which should be true after the resolve.
    glStencilFunc(GL_EQUAL, 0x1, 0xFF);
    drawQuad(drawRed.get(), essl3_shaders::PositionAttrib(), 0.5f);
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);

    ASSERT_GL_NO_ERROR();
}

// Test resolving a multisampled stencil buffer with scissor.
TEST_P(BlitFramebufferTest, ScissoredMultisampleStencil)
{
    // Incorrect rendering results seen on AMD Windows OpenGL. http://anglebug.com/2486
    ANGLE_SKIP_TEST_IF(IsAMD() && IsOpenGL() && IsWindows());

    // Fails verifying that the middle pixel is red. http://anglebug.com/3496
    ANGLE_SKIP_TEST_IF((IsIntel() || IsAMD()) && IsOSX());

    constexpr GLuint kSize = 256;

    // Create the resolve framebuffer.
    GLTexture destColorbuf;
    glBindTexture(GL_TEXTURE_2D, destColorbuf.get());
    glTexStorage2D(GL_TEXTURE_2D, 1, GL_RGBA8, kSize, kSize);

    GLRenderbuffer destRenderbuf;
    glBindRenderbuffer(GL_RENDERBUFFER, destRenderbuf.get());
    glRenderbufferStorage(GL_RENDERBUFFER, GL_STENCIL_INDEX8, kSize, kSize);

    GLFramebuffer resolved;
    glBindFramebuffer(GL_FRAMEBUFFER, resolved.get());
    glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
                           destColorbuf.get(), 0);
    glFramebufferRenderbuffer(GL_DRAW_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER,
                              destRenderbuf.get());

    // Clear the resolved buffer with gray and 0x10 stencil.
    GLColor gray(127, 127, 127, 255);
    glClearStencil(0x10);
    glClearColor(0.499f, 0.499f, 0.499f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
    EXPECT_PIXEL_COLOR_EQ(0, 0, gray);
    EXPECT_PIXEL_COLOR_EQ(kSize / 2, kSize / 2, gray);

    // Create the multisampled framebuffer.
    GLRenderbuffer renderbuf;
    glBindRenderbuffer(GL_RENDERBUFFER, renderbuf.get());
    glRenderbufferStorageMultisample(GL_RENDERBUFFER, 2, GL_STENCIL_INDEX8, kSize, kSize);

    ANGLE_GL_PROGRAM(drawRed, essl3_shaders::vs::Simple(), essl3_shaders::fs::Red());
    ANGLE_GL_PROGRAM(drawGreen, essl3_shaders::vs::Simple(), essl3_shaders::fs::Green());
    ANGLE_GL_PROGRAM(drawBlue, essl3_shaders::vs::Simple(), essl3_shaders::fs::Blue());

    GLFramebuffer framebuffer;
    glBindFramebuffer(GL_FRAMEBUFFER, framebuffer.get());
    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER,
                              renderbuf.get());

    ASSERT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));

    // Fill the stencil buffer with 0x1.
    glClearStencil(0x1);
    glClear(GL_STENCIL_BUFFER_BIT);

    // Fill a smaller region of the buffer with 0x2.
    glEnable(GL_SCISSOR_TEST);
    glEnable(GL_STENCIL_TEST);
    glScissor(kSize / 4, kSize / 4, kSize / 2, kSize / 2);
    glStencilFunc(GL_ALWAYS, 0x2, 0xFF);
    glStencilOp(GL_REPLACE, GL_REPLACE, GL_REPLACE);
    drawQuad(drawRed.get(), essl3_shaders::PositionAttrib(), 0.5f);

    // Blit into the resolved framebuffer (with scissor still enabled).
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, resolved.get());
    glBlitFramebuffer(0, 0, kSize, kSize, 0, 0, kSize, kSize, GL_STENCIL_BUFFER_BIT, GL_NEAREST);

    glBindFramebuffer(GL_FRAMEBUFFER, resolved.get());

    ASSERT_GL_NO_ERROR();

    // Draw blue if the stencil is 0x1, which should never be true.
    glDisable(GL_SCISSOR_TEST);
    glStencilMask(0);
    glStencilFunc(GL_EQUAL, 0x1, 0xFF);
    drawQuad(drawBlue.get(), essl3_shaders::PositionAttrib(), 0.5f);
    EXPECT_PIXEL_COLOR_EQ(0, 0, gray);
    EXPECT_PIXEL_COLOR_EQ(kSize - 1, 0, gray);
    EXPECT_PIXEL_COLOR_EQ(0, kSize - 1, gray);
    EXPECT_PIXEL_COLOR_EQ(kSize - 1, kSize - 1, gray);
    EXPECT_PIXEL_COLOR_EQ(kSize / 2, kSize / 2, gray);

    // Draw red if the stencil is 0x2, which should be true in the middle after the blit/resolve.
    glStencilFunc(GL_EQUAL, 0x2, 0xFF);
    drawQuad(drawRed.get(), essl3_shaders::PositionAttrib(), 0.5f);
    EXPECT_PIXEL_COLOR_EQ(0, 0, gray);
    EXPECT_PIXEL_COLOR_EQ(kSize - 1, 0, gray);
    EXPECT_PIXEL_COLOR_EQ(0, kSize - 1, gray);
    EXPECT_PIXEL_COLOR_EQ(kSize - 1, kSize - 1, gray);
    EXPECT_PIXEL_COLOR_EQ(kSize / 2, kSize / 2, GLColor::red);

    // Draw green if the stencil is 0x10, which should be left untouched in the outer regions.
    glStencilFunc(GL_EQUAL, 0x10, 0xFF);
    drawQuad(drawGreen.get(), essl3_shaders::PositionAttrib(), 0.5f);
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(kSize - 1, 0, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(0, kSize - 1, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(kSize - 1, kSize - 1, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(kSize / 2, kSize / 2, GLColor::red);

    ASSERT_GL_NO_ERROR();
}

// Test blitting from a texture with non-zero base.  The blit is non-stretching and between
// identical formats so that the path that uses vkCmdBlitImage is taken.
TEST_P(BlitFramebufferTest, NonZeroBaseSource)
{
    // http://anglebug.com/5001
    ANGLE_SKIP_TEST_IF(IsOpenGL() && IsIntel() && IsOSX());

    ANGLE_GL_PROGRAM(drawRed, essl3_shaders::vs::Simple(), essl3_shaders::fs::Red());

    // Create a framebuffer for source data.  It usea a non-zero base.
    GLTexture srcColor;
    glBindTexture(GL_TEXTURE_2D, srcColor);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, 256, 256, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
    glTexImage2D(GL_TEXTURE_2D, 1, GL_RGBA8, 256, 256, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_BASE_LEVEL, 1);

    GLFramebuffer srcFramebuffer;
    glBindFramebuffer(GL_FRAMEBUFFER, srcFramebuffer);
    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, srcColor, 1);
    ASSERT_GL_FRAMEBUFFER_COMPLETE(GL_FRAMEBUFFER);

    // fill the color buffer with red.
    drawQuad(drawRed.get(), essl3_shaders::PositionAttrib(), 0.5f);

    // Create a framebuffer for blit destination.
    GLTexture dstColor;
    glBindTexture(GL_TEXTURE_2D, dstColor);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, 256, 256, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);

    GLFramebuffer dstFramebuffer;
    glBindFramebuffer(GL_FRAMEBUFFER, dstFramebuffer);
    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, dstColor, 0);
    ASSERT_GL_FRAMEBUFFER_COMPLETE(GL_FRAMEBUFFER);

    // Blit.  Note: no stretching is done so that vkCmdBlitImage can be used.
    glBindFramebuffer(GL_READ_FRAMEBUFFER, srcFramebuffer);
    glBlitFramebuffer(0, 0, 256, 256, 0, 0, 256, 256, GL_COLOR_BUFFER_BIT, GL_NEAREST);

    glBindFramebuffer(GL_FRAMEBUFFER, dstFramebuffer);

    ASSERT_GL_NO_ERROR();

    // Make sure the blit is done.
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);

    ASSERT_GL_NO_ERROR();
}

// Test blitting to a texture with non-zero base.  The blit is non-stretching and between
// identical formats so that the path that uses vkCmdBlitImage is taken.
TEST_P(BlitFramebufferTest, NonZeroBaseDestination)
{
    ANGLE_GL_PROGRAM(drawRed, essl3_shaders::vs::Simple(), essl3_shaders::fs::Red());

    // Create a framebuffer for source data.  It usea a non-zero base.
    GLTexture srcColor;
    glBindTexture(GL_TEXTURE_2D, srcColor);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, 256, 256, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);

    GLFramebuffer srcFramebuffer;
    glBindFramebuffer(GL_FRAMEBUFFER, srcFramebuffer);
    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, srcColor, 0);
    ASSERT_GL_FRAMEBUFFER_COMPLETE(GL_FRAMEBUFFER);

    // fill the color buffer with red.
    drawQuad(drawRed.get(), essl3_shaders::PositionAttrib(), 0.5f);

    // Create a framebuffer for blit destination.
    GLTexture dstColor;
    glBindTexture(GL_TEXTURE_2D, dstColor);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, 256, 256, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
    glTexImage2D(GL_TEXTURE_2D, 1, GL_RGBA8, 256, 256, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_BASE_LEVEL, 1);

    GLFramebuffer dstFramebuffer;
    glBindFramebuffer(GL_FRAMEBUFFER, dstFramebuffer);
    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, dstColor, 1);
    ASSERT_GL_FRAMEBUFFER_COMPLETE(GL_FRAMEBUFFER);

    // Blit.  Note: no stretching is done so that vkCmdBlitImage can be used.
    glBindFramebuffer(GL_READ_FRAMEBUFFER, srcFramebuffer);
    glBlitFramebuffer(0, 0, 256, 256, 0, 0, 256, 256, GL_COLOR_BUFFER_BIT, GL_NEAREST);

    glBindFramebuffer(GL_FRAMEBUFFER, dstFramebuffer);

    ASSERT_GL_NO_ERROR();

    // Make sure the blit is done.
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);

    ASSERT_GL_NO_ERROR();
}

// Test blitting from a stencil buffer with non-zero base.
TEST_P(BlitFramebufferTest, NonZeroBaseSourceStencil)
{
    // http://anglebug.com/5001
    ANGLE_SKIP_TEST_IF(IsOpenGL() && IsIntel() && IsOSX());

    // http://anglebug.com/5106
    ANGLE_SKIP_TEST_IF(IsMetal() && IsIntel() && IsOSX());

    ANGLE_GL_PROGRAM(drawRed, essl3_shaders::vs::Simple(), essl3_shaders::fs::Red());

    // Create a framebuffer with an attachment that has non-zero base
    GLTexture stencilTexture;
    glBindTexture(GL_TEXTURE_2D, stencilTexture);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH24_STENCIL8, 256, 256, 0, GL_DEPTH_STENCIL,
                 GL_UNSIGNED_INT_24_8, nullptr);
    glTexImage2D(GL_TEXTURE_2D, 1, GL_DEPTH24_STENCIL8, 256, 256, 0, GL_DEPTH_STENCIL,
                 GL_UNSIGNED_INT_24_8, nullptr);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_BASE_LEVEL, 1);

    GLFramebuffer srcFramebuffer;
    glBindFramebuffer(GL_FRAMEBUFFER, srcFramebuffer);
    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_TEXTURE_2D, stencilTexture, 1);
    ASSERT_GL_FRAMEBUFFER_COMPLETE(GL_FRAMEBUFFER);

    // fill the stencil buffer with 0x1
    glStencilFunc(GL_ALWAYS, 0x1, 0xFF);
    glStencilOp(GL_REPLACE, GL_REPLACE, GL_REPLACE);
    glEnable(GL_STENCIL_TEST);
    drawQuad(drawRed.get(), essl3_shaders::PositionAttrib(), 0.5f);

    // Create a framebuffer with an attachment that has non-zero base
    GLTexture colorTexture;
    glBindTexture(GL_TEXTURE_2D, colorTexture);
    glTexStorage2D(GL_TEXTURE_2D, 1, GL_RGBA8, 256, 256);

    GLRenderbuffer renderbuf;
    glBindRenderbuffer(GL_RENDERBUFFER, renderbuf);
    glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8, 256, 256);

    GLFramebuffer dstFramebuffer;
    glBindFramebuffer(GL_FRAMEBUFFER, dstFramebuffer);
    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, colorTexture, 0);
    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER, renderbuf);
    ASSERT_GL_FRAMEBUFFER_COMPLETE(GL_FRAMEBUFFER);

    // Blit stencil.
    glBindFramebuffer(GL_READ_FRAMEBUFFER, srcFramebuffer);
    glBlitFramebuffer(0, 0, 256, 256, 0, 0, 256, 256, GL_STENCIL_BUFFER_BIT, GL_NEAREST);

    glBindFramebuffer(GL_FRAMEBUFFER, dstFramebuffer);

    ASSERT_GL_NO_ERROR();

    // Clear to green
    glClearColor(0.0f, 1.0f, 0.0f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT);
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::green);

    // Draw red if the stencil is 0x1, which should be true after the blit.
    glStencilFunc(GL_EQUAL, 0x1, 0xFF);
    drawQuad(drawRed.get(), essl3_shaders::PositionAttrib(), 0.5f);
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);

    ASSERT_GL_NO_ERROR();
}

// Test blitting to a stencil buffer with non-zero base.
TEST_P(BlitFramebufferTest, NonZeroBaseDestinationStencil)
{
    // http://anglebug.com/5001
    ANGLE_SKIP_TEST_IF(IsOpenGL() && IsIntel() && IsOSX());
    // http://anglebug.com/5106
    ANGLE_SKIP_TEST_IF(IsMetal() && (IsAMD() || IsIntel()));
    // http://anglebug.com/5003
    ANGLE_SKIP_TEST_IF(IsOpenGL() && IsIntel() && IsWindows());

    ANGLE_GL_PROGRAM(drawRed, essl3_shaders::vs::Simple(), essl3_shaders::fs::Red());

    // Create a framebuffer for source data.
    GLRenderbuffer renderbuf;
    glBindRenderbuffer(GL_RENDERBUFFER, renderbuf);
    glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8, 256, 256);

    GLFramebuffer srcFramebuffer;
    glBindFramebuffer(GL_FRAMEBUFFER, srcFramebuffer);
    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER, renderbuf);
    ASSERT_GL_FRAMEBUFFER_COMPLETE(GL_FRAMEBUFFER);

    // fill the stencil buffer with 0x1
    glStencilFunc(GL_ALWAYS, 0x1, 0xFF);
    glStencilOp(GL_REPLACE, GL_REPLACE, GL_REPLACE);
    glEnable(GL_STENCIL_TEST);
    drawQuad(drawRed.get(), essl3_shaders::PositionAttrib(), 0.5f);

    // Create a framebuffer with an attachment that has non-zero base
    GLTexture colorTexture;
    glBindTexture(GL_TEXTURE_2D, colorTexture);
    glTexStorage2D(GL_TEXTURE_2D, 1, GL_RGBA8, 256, 256);

    GLTexture stencilTexture;
    glBindTexture(GL_TEXTURE_2D, stencilTexture);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH24_STENCIL8, 256, 256, 0, GL_DEPTH_STENCIL,
                 GL_UNSIGNED_INT_24_8, nullptr);
    glTexImage2D(GL_TEXTURE_2D, 1, GL_DEPTH24_STENCIL8, 256, 256, 0, GL_DEPTH_STENCIL,
                 GL_UNSIGNED_INT_24_8, nullptr);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_BASE_LEVEL, 1);

    GLFramebuffer dstFramebuffer;
    glBindFramebuffer(GL_FRAMEBUFFER, dstFramebuffer);
    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, colorTexture, 0);
    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_TEXTURE_2D, stencilTexture, 1);
    ASSERT_GL_FRAMEBUFFER_COMPLETE(GL_FRAMEBUFFER);

    // Blit stencil.
    glBindFramebuffer(GL_READ_FRAMEBUFFER, srcFramebuffer);
    glBlitFramebuffer(0, 0, 256, 256, 0, 0, 256, 256, GL_STENCIL_BUFFER_BIT, GL_NEAREST);

    glBindFramebuffer(GL_FRAMEBUFFER, dstFramebuffer);

    ASSERT_GL_NO_ERROR();

    // Clear to green
    glClearColor(0.0f, 1.0f, 0.0f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT);
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::green);

    // Draw red if the stencil is 0x1, which should be true after the blit.
    glStencilFunc(GL_EQUAL, 0x1, 0xFF);
    drawQuad(drawRed.get(), essl3_shaders::PositionAttrib(), 0.5f);
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);

    ASSERT_GL_NO_ERROR();
}

// Test blitting to a stencil buffer with non-zero base.  Exercises the compute path in the Vulkan
// backend if stencil export is not supported.  The blit is not 1-to-1 for this path to be taken.
TEST_P(BlitFramebufferTest, NonZeroBaseDestinationStencilStretch)
{
    // http://anglebug.com/5000
    ANGLE_SKIP_TEST_IF(IsOpenGL() && IsIntel() && IsWindows());

    // http://anglebug.com/5001
    ANGLE_SKIP_TEST_IF(IsOpenGL() && IsIntel() && IsOSX());

    // http://anglebug.com/5106
    ANGLE_SKIP_TEST_IF(IsMetal() && (IsAMD() || IsIntel()));

    ANGLE_GL_PROGRAM(drawRed, essl3_shaders::vs::Simple(), essl3_shaders::fs::Red());

    // Create a framebuffer for source data.
    GLRenderbuffer renderbuf;
    glBindRenderbuffer(GL_RENDERBUFFER, renderbuf);
    glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8, 256, 256);

    GLFramebuffer srcFramebuffer;
    glBindFramebuffer(GL_FRAMEBUFFER, srcFramebuffer);
    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER, renderbuf);
    ASSERT_GL_FRAMEBUFFER_COMPLETE(GL_FRAMEBUFFER);

    // fill the stencil buffer with 0x1
    glStencilFunc(GL_ALWAYS, 0x1, 0xFF);
    glStencilOp(GL_REPLACE, GL_REPLACE, GL_REPLACE);
    glEnable(GL_STENCIL_TEST);
    drawQuad(drawRed.get(), essl3_shaders::PositionAttrib(), 0.5f);

    // Create a framebuffer with an attachment that has non-zero base
    GLTexture colorTexture;
    glBindTexture(GL_TEXTURE_2D, colorTexture);
    glTexStorage2D(GL_TEXTURE_2D, 1, GL_RGBA8, 256, 256);

    GLTexture stencilTexture;
    glBindTexture(GL_TEXTURE_2D, stencilTexture);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH24_STENCIL8, 256, 256, 0, GL_DEPTH_STENCIL,
                 GL_UNSIGNED_INT_24_8, nullptr);
    glTexImage2D(GL_TEXTURE_2D, 1, GL_DEPTH24_STENCIL8, 256, 256, 0, GL_DEPTH_STENCIL,
                 GL_UNSIGNED_INT_24_8, nullptr);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_BASE_LEVEL, 1);

    GLFramebuffer dstFramebuffer;
    glBindFramebuffer(GL_FRAMEBUFFER, dstFramebuffer);
    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, colorTexture, 0);
    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_TEXTURE_2D, stencilTexture, 1);
    ASSERT_GL_FRAMEBUFFER_COMPLETE(GL_FRAMEBUFFER);

    // Blit stencil.  Note: stretch is intentional so vkCmdBlitImage cannot be used in the Vulkan
    // backend.
    glBindFramebuffer(GL_READ_FRAMEBUFFER, srcFramebuffer);
    glBlitFramebuffer(0, 0, 256, 256, -256, -256, 512, 512, GL_STENCIL_BUFFER_BIT, GL_NEAREST);

    glBindFramebuffer(GL_FRAMEBUFFER, dstFramebuffer);

    ASSERT_GL_NO_ERROR();

    // Clear to green
    glClearColor(0.0f, 1.0f, 0.0f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT);
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::green);

    // Draw red if the stencil is 0x1, which should be true after the blit.
    glStencilFunc(GL_EQUAL, 0x1, 0xFF);
    drawQuad(drawRed.get(), essl3_shaders::PositionAttrib(), 0.5f);
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);

    ASSERT_GL_NO_ERROR();
}

// Blit an SRGB framebuffer and scale it.
TEST_P(BlitFramebufferTest, BlitSRGBToRGBAndScale)
{
    constexpr const GLsizei kWidth  = 256;
    constexpr const GLsizei kHeight = 256;

    GLRenderbuffer sourceRBO, targetRBO;
    GLFramebuffer sourceFBO, targetFBO;
    initColorFBOWithCheckerPattern(&sourceFBO, &sourceRBO, GL_SRGB8_ALPHA8, kWidth * 2,
                                   kHeight * 2);
    initColorFBO(&targetFBO, &targetRBO, GL_RGBA8, kWidth, kHeight);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_READ_FRAMEBUFFER, sourceFBO);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, targetFBO);

    glViewport(0, 0, kWidth, kHeight);

    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
    glClear(GL_COLOR_BUFFER_BIT);

    // Scale down without flipping.
    glBlitFramebuffer(0, 0, kWidth * 2, kHeight * 2, 0, 0, kWidth, kHeight, GL_COLOR_BUFFER_BIT,
                      GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, targetFBO);

    EXPECT_PIXEL_COLOR_EQ(kWidth / 4, kHeight / 4, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 4, 3 * kHeight / 4, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4, kHeight / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4, 3 * kHeight / 4, GLColor::yellow);

    glBindFramebuffer(GL_READ_FRAMEBUFFER, sourceFBO);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, targetFBO);

    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
    glClear(GL_COLOR_BUFFER_BIT);

    // Scale down and flip in the X direction.
    glBlitFramebuffer(0, 0, kWidth * 2, kHeight * 2, kWidth, 0, 0, kHeight, GL_COLOR_BUFFER_BIT,
                      GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, targetFBO);

    EXPECT_PIXEL_COLOR_EQ(kWidth / 4, kHeight / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 4, 3 * kHeight / 4, GLColor::yellow);
    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4, kHeight / 4, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4, 3 * kHeight / 4, GLColor::green);
}

// Blit stencil, with scissor and scale it.
TEST_P(BlitFramebufferTest, BlitStencilScissoredScaled)
{
    // http://anglebug.com/5106
    ANGLE_SKIP_TEST_IF(IsMetal() && IsIntel() && IsOSX());

    constexpr GLint kSize = 256;

    // Create the destination framebuffer.
    GLTexture destColorbuf;
    glBindTexture(GL_TEXTURE_2D, destColorbuf.get());
    glTexStorage2D(GL_TEXTURE_2D, 1, GL_RGBA8, kSize, kSize);

    GLRenderbuffer destRenderbuf;
    glBindRenderbuffer(GL_RENDERBUFFER, destRenderbuf.get());
    glRenderbufferStorage(GL_RENDERBUFFER, GL_STENCIL_INDEX8, kSize, kSize);

    GLFramebuffer destFBO;
    glBindFramebuffer(GL_FRAMEBUFFER, destFBO.get());
    glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
                           destColorbuf.get(), 0);
    glFramebufferRenderbuffer(GL_DRAW_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER,
                              destRenderbuf.get());

    // Clear the destination buffer with gray and 0x10 stencil.
    GLColor gray(127, 127, 127, 255);
    glClearStencil(0x10);
    glClearColor(0.499f, 0.499f, 0.499f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
    EXPECT_PIXEL_COLOR_EQ(0, 0, gray);
    EXPECT_PIXEL_COLOR_EQ(kSize / 2, kSize / 2, gray);

    // Create the source framebuffer.
    GLRenderbuffer renderbuf;
    glBindRenderbuffer(GL_RENDERBUFFER, renderbuf.get());
    glRenderbufferStorage(GL_RENDERBUFFER, GL_STENCIL_INDEX8, kSize, kSize);

    ANGLE_GL_PROGRAM(drawRed, essl3_shaders::vs::Simple(), essl3_shaders::fs::Red());
    ANGLE_GL_PROGRAM(drawGreen, essl3_shaders::vs::Simple(), essl3_shaders::fs::Green());
    ANGLE_GL_PROGRAM(drawBlue, essl3_shaders::vs::Simple(), essl3_shaders::fs::Blue());

    GLFramebuffer sourceFBO;
    glBindFramebuffer(GL_FRAMEBUFFER, sourceFBO.get());
    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER,
                              renderbuf.get());

    ASSERT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));

    // Fill the stencil buffer with 0x1.
    glClearStencil(0x1);
    glClear(GL_STENCIL_BUFFER_BIT);

    // Fill a smaller region of the buffer with 0x2.
    glEnable(GL_SCISSOR_TEST);
    glEnable(GL_STENCIL_TEST);
    glScissor(kSize / 4, kSize / 4, kSize / 2, kSize / 2);
    glStencilFunc(GL_ALWAYS, 0x2, 0xFF);
    glStencilOp(GL_REPLACE, GL_REPLACE, GL_REPLACE);
    drawQuad(drawRed.get(), essl3_shaders::PositionAttrib(), 0.5f);

    // Blit and scale down into the destination framebuffer (with scissor still enabled).
    //
    // Source looks like this:
    //
    //     +----|----|----|----+
    //     |                   |
    //     |       0x1         |
    //     -    +---------+    -
    //     |    |         |    |
    //     |    |         |    |
    //     -    |   0x2   |    -
    //     |    |         |    |
    //     |    |         |    |
    //     -    +---------+    -
    //     |                   |
    //     |                   |
    //     +----|----|----|----+
    //
    // We want the destination to look like this:
    //
    //     +----|----|----|----+
    //     |                   |
    //     |       0x10        |
    //     -    +---------+    -
    //     |    |  0x1    |    |
    //     |    |  +------+    |
    //     -    |  |      |    -
    //     |    |  | 0x2  |    |
    //     |    |  |      |    |
    //     -    +--+------+    -
    //     |                   |
    //     |                   |
    //     +----|----|----|----+
    //
    // The corresponding blit would be: (0, 0, 3/4, 3/4) -> (1/4, 1/4, 3/4, 3/4).  For testing, we
    // would like to avoid having the destination area and scissor to match.  Using destination
    // area as (0, 0, 1, 1), and keeping the same scaling, the source area should be
    // (-3/8, -3/8, 9/8, 9/8).
    //
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, destFBO.get());
    constexpr GLint kBlitSrc[2] = {-3 * kSize / 8, 9 * kSize / 8};
    glBlitFramebuffer(kBlitSrc[0], kBlitSrc[0], kBlitSrc[1], kBlitSrc[1], 0, 0, kSize, kSize,
                      GL_STENCIL_BUFFER_BIT, GL_NEAREST);

    glBindFramebuffer(GL_FRAMEBUFFER, destFBO.get());

    ASSERT_GL_NO_ERROR();

    // Draw blue if the stencil is 0x1, which should be true only in the top and left of the inner
    // square.
    glDisable(GL_SCISSOR_TEST);
    glStencilMask(0);
    glStencilFunc(GL_EQUAL, 0x1, 0xFF);
    drawQuad(drawBlue.get(), essl3_shaders::PositionAttrib(), 0.5f);
    EXPECT_PIXEL_COLOR_EQ(0, 0, gray);
    EXPECT_PIXEL_COLOR_EQ(kSize - 1, 0, gray);
    EXPECT_PIXEL_COLOR_EQ(0, kSize - 1, gray);
    EXPECT_PIXEL_COLOR_EQ(kSize - 1, kSize - 1, gray);

    EXPECT_PIXEL_COLOR_EQ(kSize / 4, kSize / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(kSize / 4, 3 * kSize / 4 - 1, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * kSize / 4 - 1, kSize / 4, GLColor::blue);

    EXPECT_PIXEL_COLOR_EQ(kSize / 2, kSize / 2, gray);
    EXPECT_PIXEL_COLOR_EQ(3 * kSize / 4 - 1, 3 * kSize / 4 - 1, gray);

    // Draw red if the stencil is 0x2, which should be true in the bottom/right of the middle
    // square after the blit.
    glStencilFunc(GL_EQUAL, 0x2, 0xFF);
    drawQuad(drawRed.get(), essl3_shaders::PositionAttrib(), 0.5f);
    EXPECT_PIXEL_COLOR_EQ(0, 0, gray);
    EXPECT_PIXEL_COLOR_EQ(kSize - 1, 0, gray);
    EXPECT_PIXEL_COLOR_EQ(0, kSize - 1, gray);
    EXPECT_PIXEL_COLOR_EQ(kSize - 1, kSize - 1, gray);

    EXPECT_PIXEL_COLOR_EQ(kSize / 4, kSize / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(kSize / 4, 3 * kSize / 4 - 1, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * kSize / 4 - 1, kSize / 4, GLColor::blue);

    EXPECT_PIXEL_COLOR_EQ(kSize / 2, kSize / 2, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(3 * kSize / 4 - 1, 3 * kSize / 4 - 1, GLColor::red);

    // Draw green if the stencil is 0x10, which should be left untouched in the outer regions.
    glStencilFunc(GL_EQUAL, 0x10, 0xFF);
    drawQuad(drawGreen.get(), essl3_shaders::PositionAttrib(), 0.5f);
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(kSize - 1, 0, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(0, kSize - 1, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(kSize - 1, kSize - 1, GLColor::green);

    EXPECT_PIXEL_COLOR_EQ(kSize / 4, kSize / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(kSize / 4, 3 * kSize / 4 - 1, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * kSize / 4 - 1, kSize / 4, GLColor::blue);

    EXPECT_PIXEL_COLOR_EQ(kSize / 2, kSize / 2, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(3 * kSize / 4 - 1, 3 * kSize / 4 - 1, GLColor::red);

    ASSERT_GL_NO_ERROR();
}

// Blit a subregion of an SRGB framebuffer to an RGB framebuffer.
TEST_P(BlitFramebufferTest, PartialBlitSRGBToRGB)
{
    constexpr const GLsizei kWidth  = 256;
    constexpr const GLsizei kHeight = 256;

    GLRenderbuffer sourceRBO, targetRBO;
    GLFramebuffer sourceFBO, targetFBO;
    initColorFBOWithCheckerPattern(&sourceFBO, &sourceRBO, GL_SRGB8_ALPHA8, kWidth * 2,
                                   kHeight * 2);
    initColorFBO(&targetFBO, &targetRBO, GL_RGBA8, kWidth, kHeight);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_READ_FRAMEBUFFER, sourceFBO);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, targetFBO);

    glViewport(0, 0, kWidth, kHeight);

    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
    glClear(GL_COLOR_BUFFER_BIT);

    // Blit a part of the source FBO without flipping.
    glBlitFramebuffer(kWidth, kHeight, kWidth * 2, kHeight * 2, 0, 0, kWidth, kHeight,
                      GL_COLOR_BUFFER_BIT, GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, targetFBO);

    EXPECT_PIXEL_COLOR_EQ(kWidth / 4, kHeight / 4, GLColor::yellow);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 4, 3 * kHeight / 4, GLColor::yellow);
    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4, kHeight / 4, GLColor::yellow);
    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4, 3 * kHeight / 4, GLColor::yellow);

    glBindFramebuffer(GL_READ_FRAMEBUFFER, sourceFBO);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, targetFBO);

    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
    glClear(GL_COLOR_BUFFER_BIT);

    // Blit a part of the source FBO and flip in the X direction.
    glBlitFramebuffer(kWidth * 2, 0, kWidth, kHeight, kWidth, 0, 0, kHeight, GL_COLOR_BUFFER_BIT,
                      GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, targetFBO);

    EXPECT_PIXEL_COLOR_EQ(kWidth / 4, kHeight / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 4, 3 * kHeight / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4, kHeight / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4, 3 * kHeight / 4, GLColor::blue);
}

// Blit an SRGB framebuffer with an oversized source area (parts outside the source area should be
// clipped out).
TEST_P(BlitFramebufferTest, BlitSRGBToRGBOversizedSourceArea)
{
    constexpr const GLsizei kWidth  = 256;
    constexpr const GLsizei kHeight = 256;

    GLRenderbuffer sourceRBO, targetRBO;
    GLFramebuffer sourceFBO, targetFBO;
    initColorFBOWithCheckerPattern(&sourceFBO, &sourceRBO, GL_SRGB8_ALPHA8, kWidth, kHeight);
    initColorFBO(&targetFBO, &targetRBO, GL_RGBA8, kWidth, kHeight);

    EXPECT_GL_NO_ERROR();

    glViewport(0, 0, kWidth, kHeight);

    glBindFramebuffer(GL_READ_FRAMEBUFFER, sourceFBO);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, targetFBO);

    glClearColor(0.0f, 0.0f, 1.0f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT);

    // Blit so that the source area gets placed at the center of the target FBO.
    // The width of the source area is 1/4 of the width of the target FBO.
    glBlitFramebuffer(-3 * kWidth / 2, -3 * kHeight / 2, 5 * kWidth / 2, 5 * kHeight / 2, 0, 0,
                      kWidth, kHeight, GL_COLOR_BUFFER_BIT, GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, targetFBO);

    // Source FBO colors can be found in the middle of the target FBO.
    EXPECT_PIXEL_COLOR_EQ(7 * kWidth / 16, 7 * kHeight / 16, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(7 * kWidth / 16, 9 * kHeight / 16, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(9 * kWidth / 16, 7 * kHeight / 16, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(9 * kWidth / 16, 9 * kHeight / 16, GLColor::yellow);

    // Clear color should remain around the edges of the target FBO (WebGL 2.0 spec explicitly
    // requires this and ANGLE is expected to follow that).
    EXPECT_PIXEL_COLOR_EQ(kWidth / 4, kHeight / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 4, 3 * kHeight / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4, kHeight / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4, 3 * kHeight / 4, GLColor::blue);
}

// Blit an SRGB framebuffer with an oversized dest area (even though the result is clipped, it
// should be scaled as if the whole dest area was used).
TEST_P(BlitFramebufferTest, BlitSRGBToRGBOversizedDestArea)
{
    constexpr const GLsizei kWidth  = 256;
    constexpr const GLsizei kHeight = 256;

    GLRenderbuffer sourceRBO, targetRBO;
    GLFramebuffer sourceFBO, targetFBO;
    initColorFBOWithCheckerPattern(&sourceFBO, &sourceRBO, GL_SRGB8_ALPHA8, kWidth, kHeight);
    initColorFBO(&targetFBO, &targetRBO, GL_RGBA8, kWidth, kHeight);

    EXPECT_GL_NO_ERROR();

    glViewport(0, 0, kWidth, kHeight);

    glClearColor(0.0f, 0.0f, 1.0f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT);

    // Dest is oversized but centered the same as source
    glBindFramebuffer(GL_READ_FRAMEBUFFER, sourceFBO);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, targetFBO);

    glBlitFramebuffer(0, 0, kWidth, kHeight, -kWidth / 2, -kHeight / 2, 3 * kWidth / 2,
                      3 * kHeight / 2, GL_COLOR_BUFFER_BIT, GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, targetFBO);

    // Expected result:
    //
    //     +-------+-------+
    //     |       |       |
    //     |   R   |   B   |
    //     |       |       |
    //     +-------+-------+
    //     |       |       |
    //     |   G   |   Y   |
    //     |       |       |
    //     +-------+-------+
    //
    EXPECT_PIXEL_COLOR_EQ(1, 1, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 4, kHeight / 4, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 2 - 1, kHeight / 2 - 1, GLColor::red);

    EXPECT_PIXEL_COLOR_EQ(1, kWidth - 1, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 4, 3 * kHeight / 4, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 2 - 1, kHeight / 2 + 1, GLColor::green);

    EXPECT_PIXEL_COLOR_EQ(kWidth - 1, 1, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4, kHeight / 4, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 2 + 1, kHeight / 2 - 1, GLColor::blue);

    EXPECT_PIXEL_COLOR_EQ(kWidth - 1, kHeight - 1, GLColor::yellow);
    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4, 3 * kHeight / 4, GLColor::yellow);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 2 + 1, kHeight / 2 + 1, GLColor::yellow);

    // Dest is oversized in the negative direction
    glBindFramebuffer(GL_READ_FRAMEBUFFER, sourceFBO);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, targetFBO);

    glBlitFramebuffer(0, 0, kWidth, kHeight, -kWidth / 2, -kHeight / 2, kWidth, kHeight,
                      GL_COLOR_BUFFER_BIT, GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, targetFBO);

    // Expected result:
    //
    //     Width / 4
    //         |
    //         V
    //     +---+-----------+
    //     | R |     B     |
    //     +---+-----------+ <- Height / 4
    //     |   |           |
    //     |   |           |
    //     | G |     Y     |
    //     |   |           |
    //     |   |           |
    //     +---+-----------+
    //
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(0, kHeight / 4 - 1, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 4 - 1, 0, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 4 - 1, kHeight / 4 - 1, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 8, kHeight / 8, GLColor::red);

    EXPECT_PIXEL_COLOR_EQ(0, kHeight / 4 + 1, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(0, kHeight - 1, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 4 - 1, kHeight / 4 + 1, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 4 - 1, kHeight - 1, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 8, kHeight / 2, GLColor::green);

    EXPECT_PIXEL_COLOR_EQ(kWidth / 4 + 1, 0, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 4 + 1, kHeight / 4 - 1, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(kWidth - 1, 0, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(kWidth - 1, kHeight / 4 - 1, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 2, kHeight / 8, GLColor::blue);

    EXPECT_PIXEL_COLOR_EQ(kWidth / 4 + 1, kHeight / 4 + 1, GLColor::yellow);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 4 + 1, kHeight - 1, GLColor::yellow);
    EXPECT_PIXEL_COLOR_EQ(kWidth - 1, kHeight / 4 + 1, GLColor::yellow);
    EXPECT_PIXEL_COLOR_EQ(kWidth - 1, kHeight - 1, GLColor::yellow);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 2, kHeight / 2, GLColor::yellow);

    // Dest is oversized in the positive direction
    glBindFramebuffer(GL_READ_FRAMEBUFFER, sourceFBO);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, targetFBO);

    glBlitFramebuffer(0, 0, kWidth, kHeight, 0, 0, 3 * kWidth / 2, 3 * kHeight / 2,
                      GL_COLOR_BUFFER_BIT, GL_NEAREST);

    EXPECT_GL_NO_ERROR();

    glBindFramebuffer(GL_FRAMEBUFFER, targetFBO);

    // Expected result:
    //
    //           3 * Width / 4
    //                 |
    //                 V
    //     +-----------+---+
    //     |           |   |
    //     |           |   |
    //     |     R     | B |
    //     |           |   |
    //     |           |   |
    //     +-----------+---+ <- 3 * Height / 4
    //     |     G     | Y |
    //     +-----------+---+
    //
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(0, 3 * kHeight / 4 - 1, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4 - 1, 0, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4 - 1, 3 * kHeight / 4 - 1, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 2, kHeight / 2, GLColor::red);

    EXPECT_PIXEL_COLOR_EQ(0, 3 * kHeight / 4 + 1, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(0, kHeight - 1, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4 - 1, 3 * kHeight / 4 + 1, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4 - 1, kHeight - 1, GLColor::green);
    EXPECT_PIXEL_COLOR_EQ(kWidth / 2, 7 * kHeight / 8, GLColor::green);

    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4 + 1, 0, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4 + 1, 3 * kHeight / 4 - 1, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(kWidth - 1, 0, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(kWidth - 1, 3 * kHeight / 4 - 1, GLColor::blue);
    EXPECT_PIXEL_COLOR_EQ(7 * kWidth / 8, kHeight / 2, GLColor::blue);

    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4 + 1, 3 * kHeight / 4 + 1, GLColor::yellow);
    EXPECT_PIXEL_COLOR_EQ(3 * kWidth / 4 + 1, kHeight - 1, GLColor::yellow);
    EXPECT_PIXEL_COLOR_EQ(kWidth - 1, 3 * kHeight / 4 + 1, GLColor::yellow);
    EXPECT_PIXEL_COLOR_EQ(kWidth - 1, kHeight - 1, GLColor::yellow);
    EXPECT_PIXEL_COLOR_EQ(7 * kWidth / 8, 7 * kHeight / 8, GLColor::yellow);
}

// Test blitFramebuffer size overflow checks. WebGL 2.0 spec section 5.41. We do validation for
// overflows also in non-WebGL mode to avoid triggering driver bugs.
TEST_P(BlitFramebufferTest, BlitFramebufferSizeOverflow)
{
    GLTexture textures[2];
    glBindTexture(GL_TEXTURE_2D, textures[0]);
    glTexStorage2D(GL_TEXTURE_2D, 3, GL_RGBA8, 4, 4);
    glBindTexture(GL_TEXTURE_2D, textures[1]);
    glTexStorage2D(GL_TEXTURE_2D, 3, GL_RGBA8, 4, 4);

    GLFramebuffer framebuffers[2];
    glBindFramebuffer(GL_READ_FRAMEBUFFER, framebuffers[0]);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, framebuffers[1]);

    ASSERT_GL_NO_ERROR();

    glFramebufferTexture2D(GL_READ_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, textures[0],
                           0);
    glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, textures[1],
                           0);
    ASSERT_GL_NO_ERROR();

    // srcX
    glBlitFramebuffer(-1, 0, std::numeric_limits<GLint>::max(), 4, 0, 0, 4, 4, GL_COLOR_BUFFER_BIT,
                      GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_VALUE);
    glBlitFramebuffer(std::numeric_limits<GLint>::max(), 0, -1, 4, 0, 0, 4, 4, GL_COLOR_BUFFER_BIT,
                      GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_VALUE);

    // srcY
    glBlitFramebuffer(0, -1, 4, std::numeric_limits<GLint>::max(), 0, 0, 4, 4, GL_COLOR_BUFFER_BIT,
                      GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_VALUE);
    glBlitFramebuffer(0, std::numeric_limits<GLint>::max(), 4, -1, 0, 0, 4, 4, GL_COLOR_BUFFER_BIT,
                      GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_VALUE);

    // dstX
    glBlitFramebuffer(0, 0, 4, 4, -1, 0, std::numeric_limits<GLint>::max(), 4, GL_COLOR_BUFFER_BIT,
                      GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_VALUE);
    glBlitFramebuffer(0, 0, 4, 4, std::numeric_limits<GLint>::max(), 0, -1, 4, GL_COLOR_BUFFER_BIT,
                      GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_VALUE);

    // dstY
    glBlitFramebuffer(0, 0, 4, 4, 0, -1, 4, std::numeric_limits<GLint>::max(), GL_COLOR_BUFFER_BIT,
                      GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_VALUE);
    glBlitFramebuffer(0, 0, 4, 4, 0, std::numeric_limits<GLint>::max(), 4, -1, GL_COLOR_BUFFER_BIT,
                      GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_VALUE);
}

// Test blitFramebuffer size overflow checks. WebGL 2.0 spec section 5.41. Similar to above test,
// but this test more accurately duplicates the behavior of the WebGL test
// conformance2/rendering/blitframebuffer-size-overflow.html, which covers a few more edge cases.
TEST_P(BlitFramebufferTest, BlitFramebufferSizeOverflow2)
{
    GLTexture textures[2];
    glBindTexture(GL_TEXTURE_2D, textures[0]);
    glTexStorage2D(GL_TEXTURE_2D, 3, GL_RGBA8, 4, 4);
    glBindTexture(GL_TEXTURE_2D, textures[1]);
    glTexStorage2D(GL_TEXTURE_2D, 3, GL_RGBA8, 4, 4);

    GLFramebuffer framebuffers[2];
    glBindFramebuffer(GL_READ_FRAMEBUFFER, framebuffers[0]);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, framebuffers[1]);

    ASSERT_GL_NO_ERROR();

    glFramebufferTexture2D(GL_READ_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, textures[0],
                           0);
    glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, textures[1],
                           0);
    ASSERT_GL_NO_ERROR();

    GLint width  = 8;
    GLint height = 8;

    GLTexture tex0;
    glBindTexture(GL_TEXTURE_2D, tex0);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, 0);

    GLFramebuffer fb0;
    glBindFramebuffer(GL_READ_FRAMEBUFFER, fb0);
    glFramebufferTexture2D(GL_READ_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, tex0, 0);

    GLTexture tex1;
    glBindTexture(GL_TEXTURE_2D, tex1);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, 0);

    GLFramebuffer fb1;
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, fb1);
    glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, tex1, 0);

    GLint max = std::numeric_limits<GLint>::max();
    // Using max 32-bit integer as blitFramebuffer parameter should succeed.
    glBlitFramebuffer(0, 0, max, max, 0, 0, width, height, GL_COLOR_BUFFER_BIT, GL_NEAREST);
    glBlitFramebuffer(0, 0, width, height, 0, 0, max, max, GL_COLOR_BUFFER_BIT, GL_NEAREST);
    glBlitFramebuffer(0, 0, max, max, 0, 0, max, max, GL_COLOR_BUFFER_BIT, GL_NEAREST);
    EXPECT_GL_NO_ERROR();

    // Using blitFramebuffer parameters where calculated width/height matches max 32-bit integer
    // should succeed
    glBlitFramebuffer(-1, -1, max - 1, max - 1, 0, 0, width, height, GL_COLOR_BUFFER_BIT,
                      GL_NEAREST);
    glBlitFramebuffer(0, 0, width, height, -1, -1, max - 1, max - 1, GL_COLOR_BUFFER_BIT,
                      GL_NEAREST);
    glBlitFramebuffer(-1, -1, max - 1, max - 1, -1, -1, max - 1, max - 1, GL_COLOR_BUFFER_BIT,
                      GL_NEAREST);
    EXPECT_GL_NO_ERROR();

    // Using source width/height greater than max 32-bit integer should fail.
    glBlitFramebuffer(-1, -1, max, max, 0, 0, width, height, GL_COLOR_BUFFER_BIT, GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_VALUE);

    // Using source width/height greater than max 32-bit integer should fail.
    glBlitFramebuffer(max, max, -1, -1, 0, 0, width, height, GL_COLOR_BUFFER_BIT, GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_VALUE);

    // Using destination width/height greater than max 32-bit integer should fail.
    glBlitFramebuffer(0, 0, width, height, -1, -1, max, max, GL_COLOR_BUFFER_BIT, GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_VALUE);

    // Using destination width/height greater than max 32-bit integer should fail.
    glBlitFramebuffer(0, 0, width, height, max, max, -1, -1, GL_COLOR_BUFFER_BIT, GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_VALUE);

    // Using both source and destination width/height greater than max 32-bit integer should fail.
    glBlitFramebuffer(-1, -1, max, max, -1, -1, max, max, GL_COLOR_BUFFER_BIT, GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_VALUE);

    // Using minimum and maximum integers for all boundaries should fail.
    glBlitFramebuffer(-max - 1, -max - 1, max, max, -max - 1, -max - 1, max, max,
                      GL_COLOR_BUFFER_BIT, GL_NEAREST);
    EXPECT_GL_ERROR(GL_INVALID_VALUE);
}

// Test an edge case in D3D11 stencil blitting on the CPU that does not properly clip the
// destination regions
TEST_P(BlitFramebufferTest, BlitFramebufferStencilClipNoIntersection)
{
    GLFramebuffer framebuffers[2];
    glBindFramebuffer(GL_READ_FRAMEBUFFER, framebuffers[0]);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, framebuffers[1]);

    GLRenderbuffer renderbuffers[2];
    glBindRenderbuffer(GL_RENDERBUFFER, renderbuffers[0]);
    glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8, 4, 4);
    glFramebufferRenderbuffer(GL_READ_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER,
                              renderbuffers[0]);

    glBindRenderbuffer(GL_RENDERBUFFER, renderbuffers[1]);
    glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8, 4, 4);
    glFramebufferRenderbuffer(GL_DRAW_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER,
                              renderbuffers[1]);

    glBlitFramebuffer(0, 0, 4, 4, 1 << 24, 1 << 24, 1 << 25, 1 << 25, GL_STENCIL_BUFFER_BIT,
                      GL_NEAREST);
    EXPECT_GL_NO_ERROR();
}

// Covers an edge case with blitting borderline values.
TEST_P(BlitFramebufferTest, OOBWrite)
{
    constexpr size_t length = 0x100000;
    GLFramebuffer rfb;
    GLFramebuffer dfb;
    GLRenderbuffer rb1;
    GLRenderbuffer rb2;
    glBindFramebuffer(GL_READ_FRAMEBUFFER, rfb);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, dfb);
    glBindRenderbuffer(GL_RENDERBUFFER, rb1);
    glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8, 0x1000, 2);
    glBindRenderbuffer(GL_RENDERBUFFER, rb2);
    glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8, 2, 2);
    glFramebufferRenderbuffer(GL_READ_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_RENDERBUFFER,
                              rb1);
    glFramebufferRenderbuffer(GL_DRAW_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_RENDERBUFFER,
                              rb2);
    glBlitFramebuffer(1, 0, 0, 1, 1, 0, (2147483648 / 2) - (length / 4) + 1, 1,
                      GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT, GL_NEAREST);
    ASSERT_GL_NO_ERROR();
}

// Test blitting a depthStencil buffer with multiple depth values to a larger size.
TEST_P(BlitFramebufferTest, BlitDepthStencilPixelByPixel)
{
    ANGLE_GL_PROGRAM(drawRed, essl3_shaders::vs::Simple(), essl3_shaders::fs::Red());

    glViewport(0, 0, 128, 1);
    glEnable(GL_DEPTH_TEST);

    GLFramebuffer srcFramebuffer;
    GLRenderbuffer srcRenderbuffer;
    glBindFramebuffer(GL_FRAMEBUFFER, srcFramebuffer);
    glBindRenderbuffer(GL_RENDERBUFFER, srcRenderbuffer);
    glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8, 128, 1);
    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_RENDERBUFFER,
                              srcRenderbuffer);
    glClearDepthf(1.0f);
    glClear(GL_DEPTH_BUFFER_BIT);

    drawQuad(drawRed, essl1_shaders::PositionAttrib(), 0.0f, 0.5f);
    glViewport(0, 0, 256, 2);

    GLFramebuffer dstFramebuffer;
    GLRenderbuffer dstRenderbuffer;
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, dstFramebuffer);
    glBindRenderbuffer(GL_RENDERBUFFER, dstRenderbuffer);
    glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8, 256, 2);
    glFramebufferRenderbuffer(GL_DRAW_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_RENDERBUFFER,
                              dstRenderbuffer);

    GLTexture dstColor;
    glBindTexture(GL_TEXTURE_2D, dstColor);
    glTexStorage2D(GL_TEXTURE_2D, 1, GL_RGBA8, 256, 2);
    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, dstColor, 0);

    glBindFramebuffer(GL_READ_FRAMEBUFFER, srcFramebuffer);
    glBlitFramebuffer(0, 0, 128, 1, 0, 0, 256, 2, GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT,
                      GL_NEAREST);

    glBindFramebuffer(GL_FRAMEBUFFER, dstFramebuffer);
    glClearColor(0.0f, 1.0f, 0.0f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT);
    glDepthMask(false);
    glDepthFunc(GL_LESS);
    drawQuad(drawRed, essl1_shaders::PositionAttrib(), -0.01f, 0.5f);
    EXPECT_PIXEL_RECT_EQ(64, 0, 128, 1, GLColor::red);

    ANGLE_GL_PROGRAM(drawBlue, essl3_shaders::vs::Simple(), essl3_shaders::fs::Blue());
    glEnable(GL_DEPTH_TEST);
    glDepthMask(false);
    glDepthFunc(GL_GREATER);
    drawQuad(drawBlue, essl1_shaders::PositionAttrib(), 0.01f, 0.5f);
    EXPECT_PIXEL_RECT_EQ(64, 0, 128, 1, GLColor::blue);
}

// Test that a draw call to a small FBO followed by a resolve of a large FBO works.
TEST_P(BlitFramebufferTestES31, DrawToSmallFBOThenResolveLargeFBO)
{
    GLFramebuffer fboMS[2];
    GLTexture textureMS[2];
    GLFramebuffer fboSS;
    GLTexture textureSS;

    // A bug in the Vulkan backend grew the render area of the previous render pass on blit, even
    // though the previous render pass belonged to an unrelated framebuffer.  This test only needs
    // to make sure that the FBO being resolved is not strictly smaller than the previous FBO which
    // was drawn to.
    constexpr GLsizei kLargeWidth  = 127;
    constexpr GLsizei kLargeHeight = 54;
    constexpr GLsizei kSmallWidth  = 37;
    constexpr GLsizei kSmallHeight = 79;

    ANGLE_GL_PROGRAM(drawRed, essl1_shaders::vs::Simple(), essl1_shaders::fs::Red());

    // Create resolve target.
    glBindTexture(GL_TEXTURE_2D, textureSS);
    glTexStorage2D(GL_TEXTURE_2D, 1, GL_RGBA8, kLargeWidth, kLargeHeight);

    glBindFramebuffer(GL_FRAMEBUFFER, fboSS);
    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, textureSS, 0);
    ASSERT_GL_FRAMEBUFFER_COMPLETE(GL_FRAMEBUFFER);

    // Create multisampled framebuffers and draw into them one by one.
    for (size_t fboIndex = 0; fboIndex < 2; ++fboIndex)
    {
        const GLsizei width  = fboIndex == 0 ? kLargeWidth : kSmallWidth;
        const GLsizei height = fboIndex == 0 ? kLargeHeight : kSmallHeight;

        glBindTexture(GL_TEXTURE_2D_MULTISAMPLE, textureMS[fboIndex]);
        glTexStorage2DMultisample(GL_TEXTURE_2D_MULTISAMPLE, 4, GL_RGBA8, width, height, GL_TRUE);

        glBindFramebuffer(GL_FRAMEBUFFER, fboMS[fboIndex]);
        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D_MULTISAMPLE,
                               textureMS[fboIndex], 0);
        ASSERT_GL_FRAMEBUFFER_COMPLETE(GL_FRAMEBUFFER);

        glViewport(0, 0, width, height);
        drawQuad(drawRed, essl1_shaders::PositionAttrib(), 0.8f);
        EXPECT_GL_NO_ERROR();
    }

    // Resolve the first FBO
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, fboSS);
    glBindFramebuffer(GL_READ_FRAMEBUFFER, fboMS[0]);

    glViewport(0, 0, kLargeWidth, kLargeHeight);
    glBlitFramebuffer(0, 0, kLargeWidth, kLargeHeight, 0, 0, kLargeWidth, kLargeHeight,
                      GL_COLOR_BUFFER_BIT, GL_NEAREST);
    EXPECT_GL_NO_ERROR();

    // Verify the resolve
    glBindFramebuffer(GL_READ_FRAMEBUFFER, fboSS);
    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);
    EXPECT_PIXEL_COLOR_EQ(kLargeWidth - 1, kLargeHeight - 1, GLColor::red);
}

// Use this to select which configurations (e.g. which renderer, which GLES major version) these
// tests should be run against.
GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(BlitFramebufferANGLETest);
ANGLE_INSTANTIATE_TEST(BlitFramebufferANGLETest,
                       ES2_D3D9(),
                       ES2_D3D11(),
                       ES2_D3D11_PRESENT_PATH_FAST(),
                       ES2_OPENGL(),
                       ES3_OPENGL(),
                       ES2_VULKAN(),
                       ES3_VULKAN(),
                       WithEmulatedPrerotation(ES3_VULKAN(), 90),
                       WithEmulatedPrerotation(ES3_VULKAN(), 180),
                       WithEmulatedPrerotation(ES3_VULKAN(), 270),
                       ES2_METAL(),
                       WithNoShaderStencilOutput(ES2_METAL()));

GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(BlitFramebufferTest);
ANGLE_INSTANTIATE_TEST_ES3_AND(BlitFramebufferTest, WithNoShaderStencilOutput(ES3_METAL()));

GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(BlitFramebufferTestES31);
ANGLE_INSTANTIATE_TEST_ES31(BlitFramebufferTestES31);
}  // namespace
kc3-lang/angle/src/tests/gl_tests/BlitFramebufferANGLETest.cpp

Commit

kc3-lang/angle /src/tests/gl_tests/BlitFramebufferANGLETest.cpp
