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

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• Hash : 25390156
  Author :
  Date : 2025-08-21T00:13:19
  

  Suppress unsafe buffers on a file-by-file basis in src/ [1 of N]
  
  In this CL, we suppress many files but stop short of actually
  enabling the warning by not removing the line from the
  unsafe_buffers_paths.txt file. That will happen in a follow-on
  CL, along with resolving any stragglers missed here.
  
  This is mostly a manual change so as to familiarize myself with
  the kinds of issues faced by the Angle codebase when applying buffer
  safety warnings.
  
  -- Re-generate affected hashes.
  -- Clang-format applied to all changed files.
  -- Add a few missing .reserve() calls to vectors as noticed.
  -- Fix some mismatches between file names and header comments.
  -- Be more consistent with header comment format (blank lines and
     trailing //-only lines when a filename comment adjoins license
     boilerplate).
  
  Bug: b/436880895
  Change-Id: I3bde5cc2059acbe8345057289214f1a26f1c34aa
  Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/6869022
  Reviewed-by: Geoff Lang <geofflang@chromium.org>
  Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
  Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>
  

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• src/tests/gl_tests/DepthStencilFormatsTest.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.
  //
  
  #ifdef UNSAFE_BUFFERS_BUILD
  #    pragma allow_unsafe_buffers
  #endif
  
  #include "test_utils/ANGLETest.h"
  #include "test_utils/gl_raii.h"
  
  #include "common/mathutil.h"
  #include "platform/autogen/FeaturesD3D_autogen.h"
  
  using namespace angle;
  
  struct ReadbackTestParam
  {
      GLuint attachment;
      GLuint format;
      GLuint type;
      void *data;
      int depthBits;
      int stencilBits;
  };
  
  class DepthStencilFormatsTestBase : public ANGLETest<>
  {
    protected:
      DepthStencilFormatsTestBase()
      {
          setWindowWidth(128);
          setWindowHeight(128);
          setConfigRedBits(8);
          setConfigGreenBits(8);
          setConfigBlueBits(8);
          setConfigAlphaBits(8);
      }
  
      bool checkTexImageFormatSupport(GLenum format, GLenum type)
      {
          EXPECT_GL_NO_ERROR();
  
          GLuint tex = 0;
          glGenTextures(1, &tex);
          glBindTexture(GL_TEXTURE_2D, tex);
          glTexImage2D(GL_TEXTURE_2D, 0, format, 1, 1, 0, format, type, nullptr);
          glDeleteTextures(1, &tex);
  
          return (glGetError() == GL_NO_ERROR);
      }
  
      bool checkTexStorageFormatSupport(GLenum internalFormat)
      {
          EXPECT_GL_NO_ERROR();
  
          GLuint tex = 0;
          glGenTextures(1, &tex);
          glBindTexture(GL_TEXTURE_2D, tex);
          glTexStorage2DEXT(GL_TEXTURE_2D, 1, internalFormat, 1, 1);
          glDeleteTextures(1, &tex);
  
          return (glGetError() == GL_NO_ERROR);
      }
  
      bool checkRenderbufferFormatSupport(GLenum internalFormat)
      {
          EXPECT_GL_NO_ERROR();
  
          GLuint rb = 0;
          glGenRenderbuffers(1, &rb);
          glBindRenderbuffer(GL_RENDERBUFFER, rb);
          glRenderbufferStorage(GL_RENDERBUFFER, internalFormat, 1, 1);
          glDeleteRenderbuffers(1, &rb);
  
          return (glGetError() == GL_NO_ERROR);
      }
  
      void verifyDepthRenderBuffer(GLenum internalFormat)
      {
          GLTexture tex;
          glBindTexture(GL_TEXTURE_2D, tex);
          glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 1, 1, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
          ASSERT_GL_NO_ERROR();
  
          GLRenderbuffer rbDepth;
          glBindRenderbuffer(GL_RENDERBUFFER, rbDepth);
          glRenderbufferStorage(GL_RENDERBUFFER, internalFormat, 1, 1);
          ASSERT_GL_NO_ERROR();
  
          GLFramebuffer fbo;
          glBindFramebuffer(GL_FRAMEBUFFER, fbo);
          glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, tex, 0);
          glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, rbDepth);
  
          EXPECT_GL_FRAMEBUFFER_COMPLETE(GL_FRAMEBUFFER);
          ASSERT_GL_NO_ERROR();
  
          ANGLE_GL_PROGRAM(programRed, essl1_shaders::vs::Simple(), essl1_shaders::fs::Red());
          glEnable(GL_DEPTH_TEST);
          glDepthFunc(GL_GEQUAL);
          glClearDepthf(0.99f);
          glClearColor(0, 0, 0, 1);
          glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  
          // Pass Depth Test and draw red
          float depthValue = 1.0f;
          drawQuad(programRed, essl1_shaders::PositionAttrib(), depthValue * 2 - 1);
          EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);
  
          ASSERT_GL_NO_ERROR();
  
          ANGLE_GL_PROGRAM(programGreen, essl1_shaders::vs::Simple(), essl1_shaders::fs::Green());
  
          // Fail Depth Test and color buffer is unchanged
          depthValue = 0.98f;
          drawQuad(programGreen, essl1_shaders::PositionAttrib(), depthValue * 2 - 1);
          EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);
  
          ASSERT_GL_NO_ERROR();
  
          ANGLE_GL_PROGRAM(programBlue, essl1_shaders::vs::Simple(), essl1_shaders::fs::Blue());
          glClearDepthf(0.0f);
          glClear(GL_DEPTH_BUFFER_BIT);
  
          // Pass Depth Test and draw blue
          depthValue = 0.01f;
          drawQuad(programBlue, essl1_shaders::PositionAttrib(), depthValue * 2 - 1);
          EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::blue);
  
          glDisable(GL_DEPTH_TEST);
          ASSERT_GL_NO_ERROR();
      }
  
      void testSetUp() override
      {
          constexpr char kVS[] = R"(precision highp float;
  attribute vec4 position;
  varying vec2 texcoord;
  
  void main()
  {
      gl_Position = position;
      texcoord = (position.xy * 0.5) + 0.5;
  })";
  
          constexpr char kFS[] = R"(precision highp float;
  uniform sampler2D tex;
  varying vec2 texcoord;
  
  void main()
  {
      gl_FragColor = texture2D(tex, texcoord);
  })";
  
          mProgram = CompileProgram(kVS, kFS);
          if (mProgram == 0)
          {
              FAIL() << "shader compilation failed.";
          }
  
          mTextureUniformLocation = glGetUniformLocation(mProgram, "tex");
          EXPECT_NE(-1, mTextureUniformLocation);
  
          glGenTextures(1, &mTexture);
          ASSERT_GL_NO_ERROR();
      }
  
      void testTearDown() override
      {
          glDeleteProgram(mProgram);
          glDeleteTextures(1, &mTexture);
      }
  
      bool hasReadDepthSupport() const { return IsGLExtensionEnabled("GL_NV_read_depth"); }
  
      bool hasReadDepthStencilSupport() const
      {
          return IsGLExtensionEnabled("GL_NV_read_depth_stencil");
      }
  
      bool hasReadStencilSupport() const { return IsGLExtensionEnabled("GL_NV_read_stencil"); }
  
      bool hasFloatDepthSupport() const { return IsGLExtensionEnabled("GL_NV_depth_buffer_float2"); }
  
      void depthStencilReadbackCase(const ReadbackTestParam &type);
  
      GLuint mProgram;
      GLuint mTexture;
      GLint mTextureUniformLocation;
  };
  
  class DepthStencilFormatsTest : public DepthStencilFormatsTestBase
  {};
  
  class DepthStencilFormatsTestES3 : public DepthStencilFormatsTestBase
  {};
  
  TEST_P(DepthStencilFormatsTest, DepthTexture)
  {
      bool shouldHaveTextureSupport = (IsGLExtensionEnabled("GL_ANGLE_depth_texture") ||
                                       IsGLExtensionEnabled("GL_OES_depth_texture"));
  
      EXPECT_EQ(shouldHaveTextureSupport,
                checkTexImageFormatSupport(GL_DEPTH_COMPONENT, GL_UNSIGNED_SHORT));
      EXPECT_EQ(shouldHaveTextureSupport,
                checkTexImageFormatSupport(GL_DEPTH_COMPONENT, GL_UNSIGNED_INT));
  
      if (IsGLExtensionEnabled("GL_EXT_texture_storage"))
      {
          EXPECT_EQ(shouldHaveTextureSupport, checkTexStorageFormatSupport(GL_DEPTH_COMPONENT16));
          EXPECT_EQ(shouldHaveTextureSupport, checkTexStorageFormatSupport(GL_DEPTH_COMPONENT32_OES));
      }
  }
  
  TEST_P(DepthStencilFormatsTest, PackedDepthStencil)
  {
      // Expected to fail in D3D9 if GL_OES_packed_depth_stencil is not present.
      // Expected to fail in D3D11 if GL_OES_packed_depth_stencil or GL_ANGLE_depth_texture is not
      // present.
  
      bool shouldHaveRenderbufferSupport = IsGLExtensionEnabled("GL_OES_packed_depth_stencil");
      EXPECT_EQ(shouldHaveRenderbufferSupport,
                checkRenderbufferFormatSupport(GL_DEPTH24_STENCIL8_OES));
  
      bool shouldHaveTextureSupport = ((IsGLExtensionEnabled("GL_OES_packed_depth_stencil") ||
                                        IsGLExtensionEnabled("GL_OES_depth_texture_cube_map")) &&
                                       IsGLExtensionEnabled("GL_OES_depth_texture")) ||
                                      IsGLExtensionEnabled("GL_ANGLE_depth_texture");
      EXPECT_EQ(shouldHaveTextureSupport,
                checkTexImageFormatSupport(GL_DEPTH_STENCIL_OES, GL_UNSIGNED_INT_24_8_OES));
  
      if (IsGLExtensionEnabled("GL_EXT_texture_storage"))
      {
          bool shouldHaveTexStorageSupport = IsGLExtensionEnabled("GL_OES_packed_depth_stencil") ||
                                             IsGLExtensionEnabled("GL_ANGLE_depth_texture");
          EXPECT_EQ(shouldHaveTexStorageSupport,
                    checkTexStorageFormatSupport(GL_DEPTH24_STENCIL8_OES));
      }
  }
  
  void DepthStencilFormatsTestBase::depthStencilReadbackCase(const ReadbackTestParam &type)
  {
      ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_OES_depth_texture"));
  
      const bool hasFloatDepth = (type.type == GL_FLOAT);
      ANGLE_SKIP_TEST_IF(hasFloatDepth && !hasFloatDepthSupport());
  
      const bool hasStencil = (type.format != GL_DEPTH_COMPONENT);
  
      const bool supportPackedDepthStencilFramebuffer = getClientMajorVersion() >= 3;
  
      const int res     = 2;
      const int destRes = 4;
  
      GLTexture tex;
      glBindTexture(GL_TEXTURE_2D, tex);
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
  
      // test level > 0
      glTexImage2D(GL_TEXTURE_2D, 1, type.format, 1, 1, 0, type.format, type.type, nullptr);
      EXPECT_GL_NO_ERROR();
  
      // test with data
      glTexImage2D(GL_TEXTURE_2D, 0, type.format, 1, 1, 0, type.format, type.type, type.data);
      EXPECT_GL_NO_ERROR();
  
      // test real thing
      glTexImage2D(GL_TEXTURE_2D, 0, type.format, res, res, 0, type.format, type.type, nullptr);
      EXPECT_GL_NO_ERROR();
  
      // test texSubImage2D
      glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 1, 1, type.format, type.type, type.data);
      EXPECT_GL_NO_ERROR();
  
      GLuint fbo = 0;
      glGenFramebuffers(1, &fbo);
      glBindFramebuffer(GL_FRAMEBUFFER, fbo);
      if (type.depthBits > 0 && type.stencilBits > 0 && !supportPackedDepthStencilFramebuffer)
      {
          glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, tex, 0);
          EXPECT_GL_NO_ERROR();
          glFramebufferTexture2D(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_TEXTURE_2D, tex, 0);
          EXPECT_GL_NO_ERROR();
      }
      else
      {
          glFramebufferTexture2D(GL_FRAMEBUFFER, type.attachment, GL_TEXTURE_2D, tex, 0);
          EXPECT_GL_NO_ERROR();
      }
  
      // Ensure DEPTH_BITS returns >= 16 bits for UNSIGNED_SHORT and UNSIGNED_INT, >= 24
      // UNSIGNED_INT_24_8_WEBGL. If there is stencil, ensure STENCIL_BITS reports >= 8 for
      // UNSIGNED_INT_24_8_WEBGL.
  
      GLint depthBits = 0;
      glGetIntegerv(GL_DEPTH_BITS, &depthBits);
      EXPECT_GE(depthBits, type.depthBits);
  
      GLint stencilBits = 0;
      glGetIntegerv(GL_STENCIL_BITS, &stencilBits);
      EXPECT_GE(stencilBits, type.stencilBits);
  
      // TODO: remove this check if the spec is updated to require these combinations to work.
      if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
      {
          // try adding a color buffer.
          GLuint colorTex = 0;
          glGenTextures(1, &colorTex);
          glBindTexture(GL_TEXTURE_2D, colorTex);
          glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
          glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
          glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
          glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
          glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, res, res, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
          glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, colorTex, 0);
          EXPECT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));
      }
  
      EXPECT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));
  
      // use the default texture to render with while we return to the depth texture.
      glBindTexture(GL_TEXTURE_2D, 0);
  
      /* Setup 2x2 depth texture:
       * 1 0.6 0.8
       * |
       * 0 0.2 0.4
       *    0---1
       */
      GLbitfield clearBits = GL_DEPTH_BUFFER_BIT;
      if (hasStencil)
      {
          clearBits |= GL_STENCIL_BUFFER_BIT;
      }
  
      const GLfloat d00 = 0.2;
      const GLfloat d01 = 0.4;
      const GLfloat d10 = 0.6;
      const GLfloat d11 = 0.8;
      glEnable(GL_SCISSOR_TEST);
      glScissor(0, 0, 1, 1);
      glClearDepthf(d00);
      glClearStencil(1);
      glClear(clearBits);
      glScissor(1, 0, 1, 1);
      glClearDepthf(d10);
      glClearStencil(2);
      glClear(clearBits);
      glScissor(0, 1, 1, 1);
      glClearDepthf(d01);
      glClearStencil(3);
      glClear(clearBits);
      glScissor(1, 1, 1, 1);
      glClearDepthf(d11);
      glClearStencil(4);
      glClear(clearBits);
      glDisable(GL_SCISSOR_TEST);
  
      GLubyte actualPixels[destRes * destRes * 8];
      glReadPixels(0, 0, destRes, destRes, GL_DEPTH_COMPONENT,
                   hasFloatDepth ? GL_FLOAT : GL_UNSIGNED_SHORT, actualPixels);
      if (hasReadDepthSupport())
      {
          EXPECT_GL_NO_ERROR();
          if (hasFloatDepth)
          {
              constexpr float kEpsilon = 0.002f;
              const float *pixels      = reinterpret_cast<const float *>(actualPixels);
              ASSERT_NEAR(pixels[0], d00, kEpsilon);
              ASSERT_NEAR(pixels[0 + destRes], d01, kEpsilon);
              ASSERT_NEAR(pixels[1], d10, kEpsilon);
              ASSERT_NEAR(pixels[1 + destRes], d11, kEpsilon);
          }
          else
          {
              constexpr unsigned short kEpsilon = 2;
              const unsigned short *pixels = reinterpret_cast<const unsigned short *>(actualPixels);
              ASSERT_NEAR(pixels[0], gl::unorm<16>(d00), kEpsilon);
              ASSERT_NEAR(pixels[0 + destRes], gl::unorm<16>(d01), kEpsilon);
              ASSERT_NEAR(pixels[1], gl::unorm<16>(d10), kEpsilon);
              ASSERT_NEAR(pixels[1 + destRes], gl::unorm<16>(d11), kEpsilon);
          }
      }
      else
      {
          EXPECT_GL_ERROR(GL_INVALID_OPERATION);
      }
      if (hasStencil)
      {
          glReadPixels(0, 0, destRes, destRes, GL_STENCIL_INDEX_OES, GL_UNSIGNED_BYTE, actualPixels);
          if (hasReadStencilSupport())
          {
              EXPECT_GL_NO_ERROR();
              ASSERT_TRUE((actualPixels[0] == 1) && (actualPixels[1] == 2) &&
                          (actualPixels[0 + destRes] == 3) && (actualPixels[1 + destRes] == 4));
          }
          else
          {
              EXPECT_GL_ERROR(GL_INVALID_OPERATION);
          }
  
          ASSERT(!hasFloatDepth);
  
          glReadPixels(0, 0, destRes, destRes, GL_DEPTH_STENCIL_OES, GL_UNSIGNED_INT_24_8_OES,
                       actualPixels);
          if (hasReadDepthStencilSupport())
          {
              EXPECT_GL_NO_ERROR();
  
              struct Pixel
              {
                  uint32_t x;
  
                  uint32_t d24() const { return x >> 8; }
  
                  uint8_t s8() const { return x & 0xff; }
              };
  
              constexpr unsigned short kEpsilon = 2;
              const Pixel *pixels               = reinterpret_cast<const Pixel *>(actualPixels);
  
              ASSERT_NEAR(pixels[0].d24(), gl::unorm<24>(d00), kEpsilon);
              ASSERT_NEAR(pixels[0 + destRes].d24(), gl::unorm<24>(d01), kEpsilon);
              ASSERT_NEAR(pixels[1].d24(), gl::unorm<24>(d10), kEpsilon);
              ASSERT_NEAR(pixels[1 + destRes].d24(), gl::unorm<24>(d11), kEpsilon);
              ASSERT_TRUE((pixels[0].s8() == 1) && (pixels[1].s8() == 2) &&
                          (pixels[0 + destRes].s8() == 3) && (pixels[1 + destRes].s8() == 4));
          }
          else
          {
              EXPECT_GL_ERROR(GL_INVALID_OPERATION);
          }
      }
  }
  
  // This test will initialize a depth texture, clear it and read it back, if possible
  TEST_P(DepthStencilFormatsTest, DepthStencilReadback_UShort)
  {
      GLuint fakeData[10]    = {0};
      ReadbackTestParam type = {
          GL_DEPTH_ATTACHMENT, GL_DEPTH_COMPONENT, GL_UNSIGNED_SHORT, fakeData, 16, 0};
      depthStencilReadbackCase(type);
  }
  
  // This test will initialize a depth texture, clear it and read it back, if possible
  TEST_P(DepthStencilFormatsTest, DepthStencilReadback_UInt)
  {
      // http://anglebug.com/40644772
      ANGLE_SKIP_TEST_IF(IsMac() && IsIntelUHD630Mobile() && IsDesktopOpenGL());
  
      GLuint fakeData[10]    = {0};
      ReadbackTestParam type = {
          GL_DEPTH_ATTACHMENT, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT, fakeData, 16, 0};
      depthStencilReadbackCase(type);
  }
  
  // This test will initialize a depth texture, clear it and read it back, if possible
  TEST_P(DepthStencilFormatsTest, DepthStencilReadback_Float)
  {
      // http://anglebug.com/40644772
      ANGLE_SKIP_TEST_IF(IsMac() && IsIntelUHD630Mobile() && IsDesktopOpenGL());
  
      GLuint fakeData[10]    = {0};
      ReadbackTestParam type = {GL_DEPTH_ATTACHMENT, GL_DEPTH_COMPONENT, GL_FLOAT, fakeData, 32, 0};
      depthStencilReadbackCase(type);
  }
  
  // This test will initialize a depth texture, clear it and read it back, if possible
  TEST_P(DepthStencilFormatsTest, DepthStencilReadback_DepthStencil)
  {
      GLuint fakeData[10]    = {0};
      ReadbackTestParam type = {
          GL_DEPTH_STENCIL_ATTACHMENT, GL_DEPTH_STENCIL, GL_UNSIGNED_INT_24_8_OES, fakeData, 24, 8};
      depthStencilReadbackCase(type);
  }
  
  // Verify that packed D/S readPixels with a D32_FLOAT_S8X24_UINT attachment
  TEST_P(DepthStencilFormatsTestES3, DepthStencilReadback_DepthFloatStencil)
  {
      ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_OES_packed_depth_stencil") ||
                         !IsGLExtensionEnabled("GL_NV_depth_buffer_float2") ||
                         !IsGLExtensionEnabled("GL_NV_read_depth") ||
                         !IsGLExtensionEnabled("GL_NV_read_depth_stencil") ||
                         !IsGLExtensionEnabled("GL_NV_read_stencil"));
  
      GLFramebuffer FBO;
      glBindFramebuffer(GL_FRAMEBUFFER, FBO);
      ASSERT_GL_NO_ERROR();
  
      GLRenderbuffer RBO;
      glBindRenderbuffer(GL_RENDERBUFFER, RBO);
      glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH32F_STENCIL8, getWindowWidth(),
                            getWindowHeight());
      glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_RENDERBUFFER, RBO);
      ASSERT_GL_NO_ERROR();
  
      constexpr float kDepthClearValue     = 0.123f;
      constexpr uint8_t kStencilClearValue = 0x42;
  
      glClearDepthf(kDepthClearValue);
      glClearStencil(kStencilClearValue);
      glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
      ASSERT_GL_NO_ERROR();
  
      struct
      {
          float depth;
          uint8_t stencil;
          char unused[3];
      } pixel = {};
      glReadPixels(0, 0, 1, 1, GL_DEPTH_STENCIL_OES, GL_FLOAT_32_UNSIGNED_INT_24_8_REV, &pixel);
      EXPECT_GL_NO_ERROR();
  
      EXPECT_FLOAT_EQ(pixel.depth, kDepthClearValue);
      EXPECT_EQ(pixel.stencil, kStencilClearValue);
  }
  
  // This test will initialize a depth texture and then render with it and verify
  // pixel correctness.
  // This is modeled after webgl-depth-texture.html
  TEST_P(DepthStencilFormatsTest, DepthTextureRender)
  {
      constexpr char kVS[] = R"(attribute vec4 a_position;
  void main()
  {
      gl_Position = a_position;
  })";
  
      constexpr char kFS[] = R"(precision mediump float;
  uniform sampler2D u_texture;
  uniform vec2 u_resolution;
  void main()
  {
      vec2 texcoord = (gl_FragCoord.xy - vec2(0.5)) / (u_resolution - vec2(1.0));
      gl_FragColor = texture2D(u_texture, texcoord);
  })";
  
      ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_OES_depth_texture") &&
                         !IsGLExtensionEnabled("GL_ANGLE_depth_texture"));
  
      bool depthTextureCubeSupport  = IsGLExtensionEnabled("GL_OES_depth_texture_cube_map");
      bool textureSrgbDecodeSupport = IsGLExtensionEnabled("GL_EXT_texture_sRGB_decode");
  
      // http://anglebug.com/42262117
      ANGLE_SKIP_TEST_IF(IsIntel() && IsWindows() && IsD3D9());
  
      const int res     = 2;
      const int destRes = 4;
      GLint resolution;
  
      ANGLE_GL_PROGRAM(program, kVS, kFS);
  
      glUseProgram(program);
      resolution = glGetUniformLocation(program, "u_resolution");
      ASSERT_NE(-1, resolution);
      glUniform2f(resolution, static_cast<float>(destRes), static_cast<float>(destRes));
  
      GLuint buffer;
      glGenBuffers(1, &buffer);
      glBindBuffer(GL_ARRAY_BUFFER, buffer);
      float verts[] = {
          1, 1, 1, -1, 1, 0, -1, -1, -1, 1, 1, 1, -1, -1, -1, 1, -1, 0,
      };
      glBufferData(GL_ARRAY_BUFFER, sizeof(verts), verts, GL_STATIC_DRAW);
      glEnableVertexAttribArray(0);
      glVertexAttribPointer(0, 3, GL_FLOAT, false, 0, 0);
  
      // OpenGL ES does not have a FLIPY PixelStore attribute
      // glPixelStorei(GL_UNPACK_FLIP)
  
      struct TypeInfo
      {
          GLuint attachment;
          GLuint format;
          GLuint type;
          void *data;
          int depthBits;
          int stencilBits;
      };
  
      GLuint fakeData[10] = {0};
  
      std::vector<TypeInfo> types = {
          {GL_DEPTH_ATTACHMENT, GL_DEPTH_COMPONENT, GL_UNSIGNED_SHORT, fakeData, 16, 0},
          {GL_DEPTH_ATTACHMENT, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT, fakeData, 16, 0},
          {GL_DEPTH_STENCIL_ATTACHMENT, GL_DEPTH_STENCIL, GL_UNSIGNED_INT_24_8_OES, fakeData, 24, 8},
      };
  
      for (const TypeInfo &type : types)
      {
          GLTexture cubeTex;
          glBindTexture(GL_TEXTURE_CUBE_MAP, cubeTex);
          ASSERT_GL_NO_ERROR();
  
          std::vector<GLuint> targets{GL_TEXTURE_CUBE_MAP_POSITIVE_X, GL_TEXTURE_CUBE_MAP_NEGATIVE_X,
                                      GL_TEXTURE_CUBE_MAP_POSITIVE_Y, GL_TEXTURE_CUBE_MAP_NEGATIVE_Y,
                                      GL_TEXTURE_CUBE_MAP_POSITIVE_Z, GL_TEXTURE_CUBE_MAP_NEGATIVE_Z};
  
          for (const GLuint target : targets)
          {
              glTexImage2D(target, 0, type.format, 1, 1, 0, type.format, type.type, nullptr);
              if (depthTextureCubeSupport)
              {
                  ASSERT_GL_NO_ERROR();
              }
              else
              {
                  EXPECT_GL_ERROR(GL_INVALID_OPERATION);
              }
          }
  
          std::vector<GLuint> filterModes = {GL_LINEAR, GL_NEAREST};
  
          const bool supportPackedDepthStencilFramebuffer = getClientMajorVersion() >= 3;
  
          for (const GLuint filterMode : filterModes)
          {
              GLTexture tex;
              glBindTexture(GL_TEXTURE_2D, tex);
              glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
              glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
              glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, filterMode);
              glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, filterMode);
              if (textureSrgbDecodeSupport)
              {
                  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_SRGB_DECODE_EXT, GL_SKIP_DECODE_EXT);
              }
  
              // test level > 0
              glTexImage2D(GL_TEXTURE_2D, 1, type.format, 1, 1, 0, type.format, type.type, nullptr);
              if (IsGLExtensionEnabled("GL_OES_depth_texture"))
              {
                  EXPECT_GL_NO_ERROR();
              }
              else
              {
                  EXPECT_GL_ERROR(GL_INVALID_OPERATION);
              }
  
              // test with data
              glTexImage2D(GL_TEXTURE_2D, 0, type.format, 1, 1, 0, type.format, type.type, type.data);
              if (IsGLExtensionEnabled("GL_OES_depth_texture"))
              {
                  EXPECT_GL_NO_ERROR();
              }
              else
              {
                  EXPECT_GL_ERROR(GL_INVALID_OPERATION);
              }
  
              // test copyTexImage2D
              glCopyTexImage2D(GL_TEXTURE_2D, 0, type.format, 0, 0, 1, 1, 0);
              GLuint error = glGetError();
              ASSERT_TRUE(error == GL_INVALID_ENUM || error == GL_INVALID_OPERATION);
  
              // test real thing
              glTexImage2D(GL_TEXTURE_2D, 0, type.format, res, res, 0, type.format, type.type,
                           nullptr);
              EXPECT_GL_NO_ERROR();
  
              // test texSubImage2D
              glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 1, 1, type.format, type.type, type.data);
              if (IsGLExtensionEnabled("GL_OES_depth_texture"))
              {
                  EXPECT_GL_NO_ERROR();
              }
              else
              {
                  EXPECT_GL_ERROR(GL_INVALID_OPERATION);
              }
  
              // test copyTexSubImage2D
              glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, 0, 1, 1);
              EXPECT_GL_ERROR(GL_INVALID_OPERATION);
  
              // test generateMipmap
              glGenerateMipmap(GL_TEXTURE_2D);
              EXPECT_GL_ERROR(GL_INVALID_OPERATION);
  
              GLuint fbo = 0;
              glGenFramebuffers(1, &fbo);
              glBindFramebuffer(GL_FRAMEBUFFER, fbo);
              if (type.depthBits > 0 && type.stencilBits > 0 && !supportPackedDepthStencilFramebuffer)
              {
                  glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, tex, 0);
                  EXPECT_GL_NO_ERROR();
                  glFramebufferTexture2D(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_TEXTURE_2D, tex,
                                         0);
                  EXPECT_GL_NO_ERROR();
              }
              else
              {
                  glFramebufferTexture2D(GL_FRAMEBUFFER, type.attachment, GL_TEXTURE_2D, tex, 0);
                  EXPECT_GL_NO_ERROR();
              }
  
              // Ensure DEPTH_BITS returns >= 16 bits for UNSIGNED_SHORT and UNSIGNED_INT, >= 24
              // UNSIGNED_INT_24_8_WEBGL. If there is stencil, ensure STENCIL_BITS reports >= 8 for
              // UNSIGNED_INT_24_8_WEBGL.
  
              GLint depthBits = 0;
              glGetIntegerv(GL_DEPTH_BITS, &depthBits);
              EXPECT_GE(depthBits, type.depthBits);
  
              GLint stencilBits = 0;
              glGetIntegerv(GL_STENCIL_BITS, &stencilBits);
              EXPECT_GE(stencilBits, type.stencilBits);
  
              // TODO: remove this check if the spec is updated to require these combinations to work.
              if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
              {
                  // try adding a color buffer.
                  GLuint colorTex = 0;
                  glGenTextures(1, &colorTex);
                  glBindTexture(GL_TEXTURE_2D, colorTex);
                  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
                  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
                  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
                  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
                  glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, res, res, 0, GL_RGBA, GL_UNSIGNED_BYTE,
                               nullptr);
                  glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
                                         colorTex, 0);
                  EXPECT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));
              }
  
              EXPECT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));
  
              // use the default texture to render with while we return to the depth texture.
              glBindTexture(GL_TEXTURE_2D, 0);
  
              /* Setup 2x2 depth texture:
               * 1 0.6 0.8
               * |
               * 0 0.2 0.4
               *    0---1
               */
              const GLfloat d00 = 0.2;
              const GLfloat d01 = 0.4;
              const GLfloat d10 = 0.6;
              const GLfloat d11 = 0.8;
              glEnable(GL_SCISSOR_TEST);
              glScissor(0, 0, 1, 1);
              glClearDepthf(d00);
              glClear(GL_DEPTH_BUFFER_BIT);
              glScissor(1, 0, 1, 1);
              glClearDepthf(d10);
              glClear(GL_DEPTH_BUFFER_BIT);
              glScissor(0, 1, 1, 1);
              glClearDepthf(d01);
              glClear(GL_DEPTH_BUFFER_BIT);
              glScissor(1, 1, 1, 1);
              glClearDepthf(d11);
              glClear(GL_DEPTH_BUFFER_BIT);
              glDisable(GL_SCISSOR_TEST);
  
              // render the depth texture.
              glBindFramebuffer(GL_FRAMEBUFFER, 0);
              glViewport(0, 0, destRes, destRes);
              glBindTexture(GL_TEXTURE_2D, tex);
              glDisable(GL_DITHER);
              glEnable(GL_DEPTH_TEST);
              glClearColor(1, 0, 0, 1);
              glClearDepthf(1.0);
              glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
              glDrawArrays(GL_TRIANGLES, 0, 6);
  
              GLubyte actualPixels[destRes * destRes * 4];
              glReadPixels(0, 0, destRes, destRes, GL_RGBA, GL_UNSIGNED_BYTE, actualPixels);
              const GLfloat eps = 0.002;
              std::vector<GLfloat> expectedMin;
              std::vector<GLfloat> expectedMax;
              if (filterMode == GL_NEAREST)
              {
                  GLfloat init[] = {d00, d00, d10, d10, d00, d00, d10, d10,
                                    d01, d01, d11, d11, d01, d01, d11, d11};
                  expectedMin.insert(expectedMin.begin(), init, init + 16);
                  expectedMax.insert(expectedMax.begin(), init, init + 16);
  
                  for (int i = 0; i < 16; i++)
                  {
                      expectedMin[i] = expectedMin[i] - eps;
                      expectedMax[i] = expectedMax[i] + eps;
                  }
              }
              else
              {
                  GLfloat initMin[] = {
                      d00 - eps, d00, d00, d10 - eps, d00,       d00, d00, d10,
                      d00,       d00, d00, d10,       d01 - eps, d01, d01, d11 - eps,
                  };
                  GLfloat initMax[] = {
                      d00 + eps, d10, d10, d10 + eps, d01,       d11, d11, d11,
                      d01,       d11, d11, d11,       d01 + eps, d11, d11, d11 + eps,
                  };
                  expectedMin.insert(expectedMin.begin(), initMin, initMin + 16);
                  expectedMax.insert(expectedMax.begin(), initMax, initMax + 16);
              }
              for (int yy = 0; yy < destRes; ++yy)
              {
                  for (int xx = 0; xx < destRes; ++xx)
                  {
                      const int t        = xx + destRes * yy;
                      const GLfloat was  = (GLfloat)(actualPixels[4 * t] / 255.0);  // 4bpp
                      const GLfloat eMin = expectedMin[t];
                      const GLfloat eMax = expectedMax[t];
                      EXPECT_TRUE(was >= eMin && was <= eMax)
                          << "At " << xx << ", " << yy << ", expected within [" << eMin << ", "
                          << eMax << "] was " << was;
                  }
              }
  
              // check limitations
              // Note: What happens if current attachment type is GL_DEPTH_STENCIL_ATTACHMENT
              // and you try to call glFramebufferTexture2D with GL_DEPTH_ATTACHMENT?
              // The webGL test this code came from expected that to fail.
              // I think due to this line in ES3 spec:
              // GL_INVALID_OPERATION is generated if textarget and texture are not compatible
              // However, that's not the behavior I'm seeing, nor does it seem that a depth_stencil
              // buffer isn't compatible with a depth attachment (e.g. stencil is unused).
              if (type.attachment == GL_DEPTH_ATTACHMENT)
              {
                  glBindFramebuffer(GL_FRAMEBUFFER, fbo);
                  glFramebufferTexture2D(GL_FRAMEBUFFER, type.attachment, GL_TEXTURE_2D, 0, 0);
                  glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_TEXTURE_2D,
                                         tex, 0);
                  EXPECT_GLENUM_NE(GL_NO_ERROR, glGetError());
                  EXPECT_GLENUM_NE(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));
                  glClear(GL_DEPTH_BUFFER_BIT);
                  EXPECT_GL_ERROR(GL_INVALID_FRAMEBUFFER_OPERATION);
                  glBindFramebuffer(GL_FRAMEBUFFER, 0);
                  EXPECT_GL_NO_ERROR();
              }
          }
      }
  }
  
  // This test will initialize a frame buffer, attaching a color and 16-bit depth buffer,
  // render to it with depth testing, and verify pixel correctness.
  TEST_P(DepthStencilFormatsTest, DepthBuffer16)
  {
      verifyDepthRenderBuffer(GL_DEPTH_COMPONENT16);
  }
  
  // This test will initialize a frame buffer, attaching a color and 24-bit depth buffer,
  // render to it with depth testing, and verify pixel correctness.
  TEST_P(DepthStencilFormatsTest, DepthBuffer24)
  {
      bool shouldHaveRenderbufferSupport = IsGLExtensionEnabled("GL_OES_depth24");
      EXPECT_EQ(shouldHaveRenderbufferSupport,
                checkRenderbufferFormatSupport(GL_DEPTH_COMPONENT24_OES));
  
      if (shouldHaveRenderbufferSupport)
      {
          verifyDepthRenderBuffer(GL_DEPTH_COMPONENT24_OES);
      }
  }
  
  TEST_P(DepthStencilFormatsTestES3, DrawWithDepth16)
  {
      GLushort data[16];
      for (unsigned int i = 0; i < 16; i++)
      {
          data[i] = std::numeric_limits<GLushort>::max();
      }
      glBindTexture(GL_TEXTURE_2D, mTexture);
      glTexStorage2D(GL_TEXTURE_2D, 1, GL_DEPTH_COMPONENT16, 4, 4);
      glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 4, 4, GL_DEPTH_COMPONENT, GL_UNSIGNED_SHORT, data);
  
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
  
      glUseProgram(mProgram);
      glUniform1i(mTextureUniformLocation, 0);
  
      glClear(GL_COLOR_BUFFER_BIT);
      drawQuad(mProgram, "position", 0.5f);
  
      ASSERT_GL_NO_ERROR();
  
      GLubyte pixel[4];
      glReadPixels(0, 0, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE, &pixel);
  
      // Only require the red and alpha channels have the correct values, the depth texture extensions
      // leave the green and blue channels undefined
      ASSERT_NEAR(255, pixel[0], 2.0);
      ASSERT_EQ(255, pixel[3]);
  }
  
  // This test reproduces a driver bug on Intel windows platforms on driver version
  // from 4815 to 4901.
  // When rendering with Stencil buffer enabled and depth buffer disabled, large
  // viewport will lead to memory leak and driver crash. And the pixel result
  // is a random value.
  TEST_P(DepthStencilFormatsTestES3, DrawWithLargeViewport)
  {
      ANGLE_SKIP_TEST_IF(IsIntel() && IsWindows());
  
      ANGLE_GL_PROGRAM(program, essl1_shaders::vs::Simple(), essl1_shaders::fs::Red());
  
      glEnable(GL_STENCIL_TEST);
      glDisable(GL_DEPTH_TEST);
  
      // The iteration is to reproduce memory leak when rendering several times.
      for (int i = 0; i < 10; ++i)
      {
          // Create offscreen fbo and its color attachment and depth stencil attachment.
          GLTexture framebufferColorTexture;
          glBindTexture(GL_TEXTURE_2D, framebufferColorTexture);
          glTexStorage2D(GL_TEXTURE_2D, 1, GL_RGBA8, getWindowWidth(), getWindowHeight());
          ASSERT_GL_NO_ERROR();
  
          GLTexture framebufferStencilTexture;
          glBindTexture(GL_TEXTURE_2D, framebufferStencilTexture);
          glTexStorage2D(GL_TEXTURE_2D, 1, GL_DEPTH24_STENCIL8, getWindowWidth(), getWindowHeight());
          ASSERT_GL_NO_ERROR();
  
          GLFramebuffer fb;
          glBindFramebuffer(GL_FRAMEBUFFER, fb);
          glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
                                 framebufferColorTexture, 0);
          glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_TEXTURE_2D,
                                 framebufferStencilTexture, 0);
  
          EXPECT_GLENUM_EQ(GL_FRAMEBUFFER_COMPLETE, glCheckFramebufferStatus(GL_FRAMEBUFFER));
          ASSERT_GL_NO_ERROR();
  
          GLint kStencilRef = 4;
          glStencilOp(GL_REPLACE, GL_REPLACE, GL_REPLACE);
          glStencilFunc(GL_ALWAYS, kStencilRef, 0xFF);
  
          float viewport[2];
          glGetFloatv(GL_MAX_VIEWPORT_DIMS, viewport);
  
          glViewport(0, 0, static_cast<GLsizei>(viewport[0]), static_cast<GLsizei>(viewport[1]));
          glBindFramebuffer(GL_DRAW_FRAMEBUFFER, fb);
  
          drawQuad(program, essl1_shaders::PositionAttrib(), 0.0f);
          ASSERT_GL_NO_ERROR();
  
          glBindFramebuffer(GL_READ_FRAMEBUFFER, fb);
          EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);
          ASSERT_GL_NO_ERROR();
      }
  }
  
  // Verify that stencil component of depth texture is uploaded
  TEST_P(DepthStencilFormatsTest, VerifyDepthStencilUploadData)
  {
      // http://anglebug.com/42262342
      // When bug is resolved we can remove this skip.
      ANGLE_SKIP_TEST_IF(IsVulkan() && IsAndroid());
  
      // http://anglebug.com/42262345
      ANGLE_SKIP_TEST_IF(IsWindows() && IsVulkan() && IsAMD());
  
      bool shouldHaveTextureSupport = (IsGLExtensionEnabled("GL_OES_packed_depth_stencil") &&
                                       IsGLExtensionEnabled("GL_OES_depth_texture")) ||
                                      (getClientMajorVersion() >= 3);
  
      ANGLE_SKIP_TEST_IF(!shouldHaveTextureSupport ||
                         !checkTexImageFormatSupport(GL_DEPTH_STENCIL_OES, GL_UNSIGNED_INT_24_8_OES));
  
      ANGLE_GL_PROGRAM(program, essl1_shaders::vs::Simple(), essl1_shaders::fs::Red());
  
      glEnable(GL_STENCIL_TEST);
      glDisable(GL_DEPTH_TEST);
      glDepthMask(GL_FALSE);
  
      glViewport(0, 0, getWindowWidth(), getWindowHeight());
      glClearColor(0, 0, 0, 1);
  
      // Create offscreen fbo and its color attachment and depth stencil attachment.
      GLTexture framebufferColorTexture;
      glBindTexture(GL_TEXTURE_2D, framebufferColorTexture);
      glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, getWindowWidth(), getWindowHeight(), 0, GL_RGBA,
                   GL_UNSIGNED_BYTE, nullptr);
      ASSERT_GL_NO_ERROR();
  
      // drawQuad's depth range is -1.0 to 1.0, so a depth value of 0.5 (0x7fffff) matches a drawQuad
      // depth of 0.0.
      std::vector<GLuint> depthStencilData(getWindowWidth() * getWindowHeight(), 0x7fffffA9);
      GLTexture framebufferStencilTexture;
      glBindTexture(GL_TEXTURE_2D, framebufferStencilTexture);
      glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_STENCIL, getWindowWidth(), getWindowHeight(), 0,
                   GL_DEPTH_STENCIL, GL_UNSIGNED_INT_24_8_OES, depthStencilData.data());
      ASSERT_GL_NO_ERROR();
  
      GLFramebuffer fb;
      glBindFramebuffer(GL_FRAMEBUFFER, fb);
      glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
                             framebufferColorTexture, 0);
  
      if (getClientMajorVersion() >= 3)
      {
          glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_TEXTURE_2D,
                                 framebufferStencilTexture, 0);
          ASSERT_GL_NO_ERROR();
      }
      else
      {
          glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D,
                                 framebufferStencilTexture, 0);
          ASSERT_GL_NO_ERROR();
          glFramebufferTexture2D(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_TEXTURE_2D,
                                 framebufferStencilTexture, 0);
          ASSERT_GL_NO_ERROR();
      }
  
      ASSERT_GL_FRAMEBUFFER_COMPLETE(GL_FRAMEBUFFER);
  
      GLint kStencilRef = 0xA9;
      glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP);
      glStencilFunc(GL_EQUAL, kStencilRef, 0xFF);
  
      glBindFramebuffer(GL_FRAMEBUFFER, fb);
  
      glClear(GL_COLOR_BUFFER_BIT);
  
      drawQuad(program, essl1_shaders::PositionAttrib(), 1.0f);
      ASSERT_GL_NO_ERROR();
  
      glBindFramebuffer(GL_FRAMEBUFFER, fb);
      EXPECT_PIXEL_RECT_EQ(0, 0, getWindowWidth(), getWindowHeight(), GLColor::red);
      ASSERT_GL_NO_ERROR();
  
      // Check Z values
  
      glClear(GL_COLOR_BUFFER_BIT);
      glDisable(GL_STENCIL_TEST);
      glEnable(GL_DEPTH_TEST);
      glDepthFunc(GL_LESS);
  
      drawQuad(program, essl1_shaders::PositionAttrib(), -0.1f);
      ASSERT_GL_NO_ERROR();
  
      EXPECT_PIXEL_RECT_EQ(0, 0, getWindowWidth(), getWindowHeight(), GLColor::red);
  
      glClear(GL_COLOR_BUFFER_BIT);
  
      drawQuad(program, essl1_shaders::PositionAttrib(), 0.1f);
      ASSERT_GL_NO_ERROR();
  
      EXPECT_PIXEL_RECT_EQ(0, 0, getWindowWidth(), getWindowHeight(), GLColor::black);
  }
  
  // Verify that depth texture's data can be uploaded correctly
  TEST_P(DepthStencilFormatsTest, VerifyDepth32UploadData)
  {
      ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_OES_depth_texture"));
  
      GLTexture tex;
      glBindTexture(GL_TEXTURE_2D, tex);
      glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 1, 1, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
      ASSERT_GL_NO_ERROR();
  
      // normalized 0.99 = 0xfd70a3d6
      std::vector<GLuint> depthData(1, 0xfd70a3d6);
      GLTexture rbDepth;
      glBindTexture(GL_TEXTURE_2D, rbDepth);
      glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, 1, 1, 0, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT,
                   depthData.data());
      ASSERT_GL_NO_ERROR();
  
      GLFramebuffer fbo;
      glBindFramebuffer(GL_FRAMEBUFFER, fbo);
      glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, tex, 0);
      glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, rbDepth, 0);
  
      EXPECT_GL_FRAMEBUFFER_COMPLETE(GL_FRAMEBUFFER);
      ASSERT_GL_NO_ERROR();
  
      ANGLE_GL_PROGRAM(programRed, essl1_shaders::vs::Simple(), essl1_shaders::fs::Red());
      glEnable(GL_DEPTH_TEST);
      glDepthFunc(GL_GEQUAL);
      glClearColor(0, 1, 0, 1);
      glClear(GL_COLOR_BUFFER_BIT);
  
      // Fail Depth Test and color buffer is unchanged
      float depthValue = 0.98f;
      drawQuad(programRed, essl1_shaders::PositionAttrib(), depthValue * 2 - 1);
      EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::green);
  
      // Pass Depth Test and draw red
      depthValue = 1.0f;
      drawQuad(programRed, essl1_shaders::PositionAttrib(), depthValue * 2 - 1);
      EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);
  
      ASSERT_GL_NO_ERROR();
  
      // Change depth texture data
      glBindTexture(GL_TEXTURE_2D, rbDepth);
      depthData[0] = 0x7fffffff;  // 0.5
      glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 1, 1, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT,
                      depthData.data());
      ASSERT_GL_NO_ERROR();
  
      ANGLE_GL_PROGRAM(programGreen, essl1_shaders::vs::Simple(), essl1_shaders::fs::Green());
  
      // Fail Depth Test and color buffer is unchanged
      depthValue = 0.48f;
      drawQuad(programGreen, essl1_shaders::PositionAttrib(), depthValue * 2 - 1);
      EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);
  
      ASSERT_GL_NO_ERROR();
  
      ANGLE_GL_PROGRAM(programBlue, essl1_shaders::vs::Simple(), essl1_shaders::fs::Blue());
      glClearDepthf(0.0f);
      glClear(GL_DEPTH_BUFFER_BIT);
  
      // Pass Depth Test and draw blue
      depthValue = 0.01f;
      drawQuad(programBlue, essl1_shaders::PositionAttrib(), depthValue * 2 - 1);
      EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::blue);
  
      glDisable(GL_DEPTH_TEST);
      ASSERT_GL_NO_ERROR();
  }
  
  // Verify that 16 bits depth texture's data can be uploaded correctly
  TEST_P(DepthStencilFormatsTest, VerifyDepth16UploadData)
  {
      ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_OES_depth_texture"));
  
      GLTexture tex;
      glBindTexture(GL_TEXTURE_2D, tex);
      glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 1, 1, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
      ASSERT_GL_NO_ERROR();
  
      // normalized 0.99 = 0xfd6f
      std::vector<GLushort> depthData(1, 0xfd6f);
      GLTexture rbDepth;
      glBindTexture(GL_TEXTURE_2D, rbDepth);
      glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, 1, 1, 0, GL_DEPTH_COMPONENT,
                   GL_UNSIGNED_SHORT, depthData.data());
      ASSERT_GL_NO_ERROR();
  
      GLFramebuffer fbo;
      glBindFramebuffer(GL_FRAMEBUFFER, fbo);
      glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, tex, 0);
      glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, rbDepth, 0);
  
      EXPECT_GL_FRAMEBUFFER_COMPLETE(GL_FRAMEBUFFER);
      ASSERT_GL_NO_ERROR();
  
      ANGLE_GL_PROGRAM(programRed, essl1_shaders::vs::Simple(), essl1_shaders::fs::Red());
      glEnable(GL_DEPTH_TEST);
      glDepthFunc(GL_GEQUAL);
      glClearColor(0, 1, 0, 1);
      glClear(GL_COLOR_BUFFER_BIT);
  
      // Fail Depth Test and color buffer is unchanged
      float depthValue = 0.98f;
      drawQuad(programRed, essl1_shaders::PositionAttrib(), depthValue * 2 - 1);
      EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::green);
  
      // Pass Depth Test and draw red
      depthValue = 1.0f;
      drawQuad(programRed, essl1_shaders::PositionAttrib(), depthValue * 2 - 1);
      EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);
  
      ASSERT_GL_NO_ERROR();
  
      // Change depth texture data
      glBindTexture(GL_TEXTURE_2D, rbDepth);
      depthData[0] = 0x7fff;  // 0.5
      glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 1, 1, GL_DEPTH_COMPONENT, GL_UNSIGNED_SHORT,
                      depthData.data());
      ASSERT_GL_NO_ERROR();
  
      ANGLE_GL_PROGRAM(programGreen, essl1_shaders::vs::Simple(), essl1_shaders::fs::Green());
  
      // Fail Depth Test and color buffer is unchanged
      depthValue = 0.48f;
      drawQuad(programGreen, essl1_shaders::PositionAttrib(), depthValue * 2 - 1);
      EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);
  
      ASSERT_GL_NO_ERROR();
  
      ANGLE_GL_PROGRAM(programBlue, essl1_shaders::vs::Simple(), essl1_shaders::fs::Blue());
      glClearDepthf(0.0f);
      glClear(GL_DEPTH_BUFFER_BIT);
  
      // Pass Depth Test and draw blue
      depthValue = 0.01f;
      drawQuad(programBlue, essl1_shaders::PositionAttrib(), depthValue * 2 - 1);
      EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::blue);
  
      glDisable(GL_DEPTH_TEST);
      ASSERT_GL_NO_ERROR();
  }
  
  class DepthStencilFormatsTestES31 : public DepthStencilFormatsTestBase
  {};
  
  // Test depth24 texture sample from fragment shader and then read access from compute
  TEST_P(DepthStencilFormatsTestES31, DrawReadDrawDispatch)
  {
      ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_OES_depth24") ||
                         !IsGLExtensionEnabled("GL_NV_read_depth"));
  
      const char kVS[] = R"(#version 310 es
  layout (location = 0) in vec3 pos;
  void main(void) {
      gl_Position = vec4(pos, 1.0);
  })";
  
      const char kFS[] = R"(#version 310 es
  precision highp float;
  uniform sampler2D tex;
  out vec4 fragColor;
  void main(void) {
          float d = texture(tex,vec2(0,0)).x;
          fragColor = vec4(d, 0, 0, 1);
  })";
  
      // Create depth texture
      GLTexture depthTexture;
      glActiveTexture(GL_TEXTURE0);
      glBindTexture(GL_TEXTURE_2D, depthTexture);
      // glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, 1);
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
      glTexStorage2D(GL_TEXTURE_2D, 1, GL_DEPTH_COMPONENT24, 1, 1);
  
      // Clear depth texture to 0.51f
      GLFramebuffer framebuffer;
      glBindFramebuffer(GL_FRAMEBUFFER, framebuffer);
      glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depthTexture, 0);
      ASSERT_GL_FRAMEBUFFER_COMPLETE(GL_FRAMEBUFFER);
      GLfloat depthValue = 0.51f;
      glClearDepthf(depthValue);
      glClear(GL_DEPTH_BUFFER_BIT);
      GLuint actualDepthValue;
      GLfloat depthErrorTolerance = 0.001f;
      glReadPixels(0, 0, 1, 1, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT, &actualDepthValue);
      EXPECT_NEAR(depthValue, actualDepthValue / (float)UINT_MAX, depthErrorTolerance);
      glBindFramebuffer(GL_FRAMEBUFFER, 0);
  
      // Render to surface with texture sample from depth texture
      ANGLE_GL_PROGRAM(graphicsProgram, kVS, kFS);
      glUseProgram(graphicsProgram);
      const auto &quadVertices = GetQuadVertices();
      GLBuffer arrayBuffer;
      glBindBuffer(GL_ARRAY_BUFFER, arrayBuffer);
      glBufferData(GL_ARRAY_BUFFER, quadVertices.size() * sizeof(Vector3), quadVertices.data(),
                   GL_STATIC_DRAW);
      GLint positionAttributeLocation = 0;
      glBindAttribLocation(graphicsProgram, positionAttributeLocation, "pos");
      glVertexAttribPointer(positionAttributeLocation, 3, GL_FLOAT, GL_FALSE, 0, 0);
      glEnableVertexAttribArray(positionAttributeLocation);
  
      GLint uTextureLocation = glGetUniformLocation(graphicsProgram, "tex");
      ASSERT_NE(-1, uTextureLocation);
      glActiveTexture(GL_TEXTURE0);
      glBindTexture(GL_TEXTURE_2D, depthTexture);
      glUniform1i(uTextureLocation, 0);
      // Sample the depth texture from fragment shader and verify. This flushes out commands which
      // ensures there will be no layout transition in next renderPass.
      glDepthMask(false);
      glDisable(GL_DEPTH_TEST);
      glDrawArrays(GL_TRIANGLES, 0, 6);
      EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor((GLubyte)(depthValue * 255), 0u, 0u, 255u));
  
      // Sample the depth texture from fragment shader. No image layout transition expected here.
      glDrawArrays(GL_TRIANGLES, 0, 6);
  
      // Sample it from compute shader while the renderPass also sample from the same texture
      constexpr char kCS[] = R"(#version 310 es
  layout(local_size_x=1, local_size_y=1, local_size_z=1) in;
  layout(std140, binding=0) buffer buf {
      vec4 outData;
  };
  uniform sampler2D u_tex2D;
  void main()
  {
      outData = texture(u_tex2D, vec2(gl_LocalInvocationID.xy));
  })";
      ANGLE_GL_COMPUTE_PROGRAM(computeProgram, kCS);
      glUseProgram(computeProgram);
      GLBuffer ssbo;
      const std::vector<GLfloat> initialData(16, 0.0f);
      glBindBuffer(GL_SHADER_STORAGE_BUFFER, ssbo);
      glBufferData(GL_SHADER_STORAGE_BUFFER, 16, initialData.data(), GL_STATIC_DRAW);
      glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 0, ssbo);
      glDispatchCompute(1, 1, 1);
      glMemoryBarrier(GL_BUFFER_UPDATE_BARRIER_BIT);
      glBindBuffer(GL_SHADER_STORAGE_BUFFER, ssbo);
      const GLfloat *ptr = reinterpret_cast<const GLfloat *>(
          glMapBufferRange(GL_SHADER_STORAGE_BUFFER, 0, 16, GL_MAP_READ_BIT));
      EXPECT_NEAR(depthValue, ptr[0], depthErrorTolerance);
      EXPECT_GL_NO_ERROR();
  }
  
  ANGLE_INSTANTIATE_TEST_ES2(DepthStencilFormatsTest);
  
  GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(DepthStencilFormatsTestES3);
  ANGLE_INSTANTIATE_TEST_ES3(DepthStencilFormatsTestES3);
  
  GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(DepthStencilFormatsTestES31);
  ANGLE_INSTANTIATE_TEST_ES31(DepthStencilFormatsTestES31);
  
  class TinyDepthStencilWorkaroundTest : public ANGLETest<>
  {
    public:
      TinyDepthStencilWorkaroundTest()
      {
          setWindowWidth(512);
          setWindowHeight(512);
          setConfigRedBits(8);
          setConfigGreenBits(8);
          setConfigBlueBits(8);
          setConfigAlphaBits(8);
      }
  };
  
  // Tests that the tiny depth stencil textures workaround does not "stick" depth textures.
  // http://anglebug.com/40644610
  TEST_P(TinyDepthStencilWorkaroundTest, DepthTexturesStick)
  {
      // http://anglebug.com/40096654
      ANGLE_SKIP_TEST_IF((IsAndroid() && IsOpenGLES()) || (IsLinux() && IsVulkan()));
  
      constexpr char kDrawVS[] =
          "#version 100\n"
          "attribute vec3 vertex;\n"
          "void main () {\n"
          "  gl_Position = vec4(vertex.x, vertex.y, vertex.z * 2.0 - 1.0, 1);\n"
          "}\n";
  
      ANGLE_GL_PROGRAM(drawProgram, kDrawVS, essl1_shaders::fs::Red());
  
      constexpr char kBlitVS[] =
          "#version 100\n"
          "attribute vec2 vertex;\n"
          "varying vec2 position;\n"
          "void main () {\n"
          "  position = vertex * .5 + .5;\n"
          "  gl_Position = vec4(vertex, 0, 1);\n"
          "}\n";
  
      constexpr char kBlitFS[] =
          "#version 100\n"
          "precision mediump float;\n"
          "uniform sampler2D texture;\n"
          "varying vec2 position;\n"
          "void main () {\n"
          "  gl_FragColor = vec4 (texture2D (texture, position).rrr, 1.);\n"
          "}\n";
  
      ANGLE_GL_PROGRAM(blitProgram, kBlitVS, kBlitFS);
  
      GLint blitTextureLocation = glGetUniformLocation(blitProgram, "texture");
      ASSERT_NE(-1, blitTextureLocation);
  
      GLTexture colorTex;
      glBindTexture(GL_TEXTURE_2D, colorTex);
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
      glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, getWindowWidth(), getWindowHeight(), 0, GL_RGBA,
                   GL_UNSIGNED_BYTE, nullptr);
      glBindTexture(GL_TEXTURE_2D, 0);
  
      GLTexture depthTex;
      glBindTexture(GL_TEXTURE_2D, depthTex);
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST_MIPMAP_NEAREST);
      ASSERT_EQ(getWindowWidth(), getWindowHeight());
      int levels = gl::log2(getWindowWidth());
      for (int mipLevel = 0; mipLevel <= levels; ++mipLevel)
      {
          int size = getWindowWidth() >> mipLevel;
          glTexImage2D(GL_TEXTURE_2D, mipLevel, GL_DEPTH_STENCIL, size, size, 0, GL_DEPTH_STENCIL,
                       GL_UNSIGNED_INT_24_8_OES, nullptr);
      }
  
      glBindTexture(GL_TEXTURE_2D, 0);
  
      ASSERT_GL_NO_ERROR();
  
      GLFramebuffer framebuffer;
      glBindFramebuffer(GL_FRAMEBUFFER, framebuffer);
  
      glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, colorTex, 0);
      glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depthTex, 0);
  
      ASSERT_GL_NO_ERROR();
  
      glDepthRangef(0.0f, 1.0f);
      glViewport(0, 0, getWindowWidth(), getWindowHeight());
      glClearColor(0, 0, 0, 1);
  
      // Draw loop.
      for (unsigned int frame = 0; frame < 3; ++frame)
      {
          // draw into FBO
          glBindFramebuffer(GL_FRAMEBUFFER, framebuffer);
          glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
  
          glEnable(GL_DEPTH_TEST);
  
          float depth = ((frame % 2 == 0) ? 0.0f : 1.0f);
          drawQuad(drawProgram, "vertex", depth);
  
          glBindFramebuffer(GL_FRAMEBUFFER, 0);
  
          // blit FBO
          glDisable(GL_DEPTH_TEST);
  
          glUseProgram(blitProgram);
          glUniform1i(blitTextureLocation, 0);
          glBindTexture(GL_TEXTURE_2D, depthTex);
  
          drawQuad(blitProgram, "vertex", 0.5f);
  
          Vector4 depthVec(depth, depth, depth, 1);
          GLColor depthColor(depthVec);
  
          EXPECT_PIXEL_COLOR_NEAR(0, 0, depthColor, 1);
          ASSERT_GL_NO_ERROR();
      }
  }
  
  // Initialize a depth texture by writing to it in a fragment shader then attempt to read it from a
  // compute shader. Regression test for D3D11 not unbinding the depth texture and the sampler binding
  // failing.
  TEST_P(DepthStencilFormatsTestES31, ReadDepthStencilInComputeShader)
  {
      constexpr char kTestVertexShader[] = R"(#version 310 es
  
  void main() {
    gl_PointSize = 1.0;
    vec2 pos[6] = vec2[6](vec2(-1.0f), vec2(1.0f, -1.0f), vec2(-1.0f, 1.0f), vec2(-1.0f, 1.0f), vec2(1.0f, -1.0f), vec2(1.0f));
    gl_Position = vec4(pos[uint(gl_VertexID)], 0.5f, 1.0f);
    return;
  }
  )";
  
      constexpr char kTestFragmentShader[] = R"(#version 310 es
  precision highp float;
  
  void main()
  {
    gl_FragDepth = 0.51f;
    return;
  }
  )";
  
      constexpr char kTestComputeShader[] = R"(#version 310 es
  
  layout(binding = 0, std430) buffer dst_buf_block_ssbo {
    float inner[];
  } dst_buf;
  
  uniform highp sampler2D tex;
  void blit_depth_to_buffer(uvec3 id) {
    uvec2 coord = (id.xy);
    uint dstOffset = (id.x + (id.y * 1u));
    dst_buf.inner[dstOffset] = texelFetch(tex, ivec2(coord), 0).x;
  }
  
  layout(local_size_x = 8, local_size_y = 8, local_size_z = 1) in;
  void main() {
    blit_depth_to_buffer(gl_GlobalInvocationID);
  }
  )";
  
      GLfloat depthValue          = 0.51f;
      GLfloat depthErrorTolerance = 0.001f;
  
      GLTexture depthTexture;
      glActiveTexture(GL_TEXTURE0);
      glBindTexture(GL_TEXTURE_2D, depthTexture);
      // glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, 1);
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
      glTexStorage2D(GL_TEXTURE_2D, 1, GL_DEPTH_COMPONENT32F, 1, 1);
  
      // Clear depth texture to depthValue
      GLFramebuffer framebuffer;
      glBindFramebuffer(GL_FRAMEBUFFER, framebuffer);
      glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depthTexture, 0);
      ASSERT_GL_FRAMEBUFFER_COMPLETE(GL_FRAMEBUFFER);
  
      // 2. Draw and write to gl_FragDepth
      ANGLE_GL_PROGRAM(graphicsProgram, kTestVertexShader, kTestFragmentShader);
      glUseProgram(graphicsProgram);
      EXPECT_GL_NO_ERROR();
  
      glDrawBuffers(0, nullptr);
      EXPECT_GL_NO_ERROR();
  
      glClearDepthf(0.8);
      glEnable(GL_DEPTH_TEST);
      glDepthFunc(GL_ALWAYS);
      glDisable(GL_CULL_FACE);
      glDepthMask(true);
      glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
      glDrawArrays(GL_TRIANGLES, 0, 6);
      EXPECT_GL_NO_ERROR();
  
      glBindFramebuffer(GL_FRAMEBUFFER, 0);
  
      ANGLE_GL_COMPUTE_PROGRAM(computeProgram, kTestComputeShader);
      glUseProgram(computeProgram);
  
      GLint uTextureLocation = glGetUniformLocation(computeProgram, "tex");
      ASSERT_NE(-1, uTextureLocation);
      glActiveTexture(GL_TEXTURE0);
      glBindTexture(GL_TEXTURE_2D, depthTexture);
      glUniform1i(uTextureLocation, 0);
  
      GLBuffer ssbo;
      std::array<GLfloat, 16> initialData{0};
      glBindBuffer(GL_SHADER_STORAGE_BUFFER, ssbo);
      glBufferData(GL_SHADER_STORAGE_BUFFER, 16, initialData.data(), GL_STATIC_DRAW);
      glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 0, ssbo);
      glDispatchCompute(1, 1, 1);
      glMemoryBarrier(GL_BUFFER_UPDATE_BARRIER_BIT);
      glBindBuffer(GL_SHADER_STORAGE_BUFFER, ssbo);
      const GLfloat *ptr = reinterpret_cast<const GLfloat *>(
          glMapBufferRange(GL_SHADER_STORAGE_BUFFER, 0, 16, GL_MAP_READ_BIT));
      EXPECT_NEAR(depthValue, ptr[0], depthErrorTolerance);
      EXPECT_GL_NO_ERROR();
  }
  
  GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(TinyDepthStencilWorkaroundTest);
  ANGLE_INSTANTIATE_TEST_ES3_AND(TinyDepthStencilWorkaroundTest,
                                 ES3_D3D11().enable(Feature::EmulateTinyStencilTextures));
  

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