Add support for OES_depth24

Allow 24-bit depth as a valid Renderbuffer format.

Bug: angleproject:3229
Test: angle_end2end_tests --gtest_filter=DepthStencilFormatsTest.DepthBuffer/*
Change-Id: I166639ec0e000595dc55848e4b8b7bef627b6471
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1661050
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>

CONTRIBUTORS

@@ -148,4 +148,6 @@ AdaptVis GmbH
  Sascha Kolodzey
 
 Samsung Electronics, Inc.
+ Brandon Schade
  Minkyu Jeong
+ Mohan Maiya

src/libANGLE/Caps.cpp

@@ -176,6 +176,7 @@ Extensions::Extensions()
       sRGB(false),
       depthTextureANGLE(false),
       depthTextureOES(false),
+      depth24OES(false),
       depth32(false),
       textureStorage(false),
       textureNPOT(false),
@@ -678,6 +679,16 @@ static bool DetermineDepthTextureOESSupport(const TextureCapsMap &textureCaps)
     return GetFormatSupport(textureCaps, requiredFormats, true, true, true, true);
 }
 
+// Check for GL_OES_depth24
+static bool DetermineDepth24OESSupport(const TextureCapsMap &textureCaps)
+{
+    constexpr GLenum requiredFormats[] = {
+        GL_DEPTH_COMPONENT24_OES,
+    };
+
+    return GetFormatSupport(textureCaps, requiredFormats, false, false, false, true);
+}
+
 // Check for GL_OES_depth32
 static bool DetermineDepth32Support(const TextureCapsMap &textureCaps)
 {
@@ -799,6 +810,7 @@ void Extensions::setTextureExtensionSupport(const TextureCapsMap &textureCaps)
     sRGB                             = DetermineSRGBTextureSupport(textureCaps);
     depthTextureANGLE                = DetermineDepthTextureANGLESupport(textureCaps);
     depthTextureOES                  = DetermineDepthTextureOESSupport(textureCaps);
+    depth24OES                       = DetermineDepth24OESSupport(textureCaps);
     depth32                          = DetermineDepth32Support(textureCaps);
     colorBufferFloatRGB              = DetermineColorBufferFloatRGBSupport(textureCaps);
     colorBufferFloatRGBA             = DetermineColorBufferFloatRGBASupport(textureCaps);
@@ -862,6 +874,7 @@ const ExtensionInfoMap &GetExtensionInfoMap()
         map["GL_EXT_sRGB"] = enableableExtension(&Extensions::sRGB);
         map["GL_ANGLE_depth_texture"] = esOnlyExtension(&Extensions::depthTextureANGLE);
         map["GL_OES_depth_texture"] = esOnlyExtension(&Extensions::depthTextureOES);
+        map["GL_OES_depth24"] = esOnlyExtension(&Extensions::depth24OES);
         map["GL_OES_depth32"] = esOnlyExtension(&Extensions::depth32);
         map["GL_EXT_texture_storage"] = enableableExtension(&Extensions::textureStorage);
         map["GL_OES_texture_npot"] = enableableExtension(&Extensions::textureNPOT);

src/libANGLE/Caps.h

@@ -244,6 +244,10 @@ struct Extensions
     // OES_depth_texture
     bool depthTextureOES;
 
+    // GL_OES_depth24
+    // Allows DEPTH_COMPONENT24_OES as a valid Renderbuffer format.
+    bool depth24OES;
+
     // GL_OES_depth32
     // Allows DEPTH_COMPONENT32_OES as a valid Renderbuffer format.
     bool depth32;

src/libANGLE/formatutils.cpp

@@ -795,7 +795,7 @@ static InternalFormatInfoMap BuildInternalFormatInfoMap()
     // ANGLE Depth stencil formats
     //                         | Internal format         |sized| D |S | X | Format            | Type                             | Component type        | Texture supported                                                | Filterable                                      | Texture attachment                                                                   | Renderbuffer                                                                         |
     AddDepthStencilFormat(&map, GL_DEPTH_COMPONENT16,     true, 16, 0,  0, GL_DEPTH_COMPONENT, GL_UNSIGNED_SHORT,                 GL_UNSIGNED_NORMALIZED, RequireES<1, 0>,                                                   RequireESOrExtOrExt<3, 0, &Extensions::depthTextureANGLE, &Extensions::depthTextureOES>, RequireES<1, 0>,                                RequireES<1, 0>                                                                       );
-    AddDepthStencilFormat(&map, GL_DEPTH_COMPONENT24,     true, 24, 0,  0, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT,                   GL_UNSIGNED_NORMALIZED, RequireES<3, 0>,                                                   RequireESOrExt<3, 0, &Extensions::depthTextureANGLE>, RequireES<3, 0>,                                                                   RequireES<3, 0>                                                                       );
+    AddDepthStencilFormat(&map, GL_DEPTH_COMPONENT24,     true, 24, 0,  0, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT,                   GL_UNSIGNED_NORMALIZED, RequireES<3, 0>,                                                   RequireESOrExt<3, 0, &Extensions::depthTextureANGLE>, RequireES<3, 0>,                                                                   RequireESOrExt<3, 0, &Extensions::depth24OES>                                            );
     AddDepthStencilFormat(&map, GL_DEPTH_COMPONENT32F,    true, 32, 0,  0, GL_DEPTH_COMPONENT, GL_FLOAT,                          GL_FLOAT,               RequireES<3, 0>,                                                   RequireESOrExt<3, 0, &Extensions::depthTextureANGLE>, RequireES<3, 0>,                                                                   RequireES<3, 0>                                                                       );
     AddDepthStencilFormat(&map, GL_DEPTH_COMPONENT32_OES, true, 32, 0,  0, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT,                   GL_UNSIGNED_NORMALIZED, RequireExtOrExtOrExt<&Extensions::depthTextureANGLE, &Extensions::depthTextureOES, &Extensions::depth32>, AlwaysSupported, RequireExtOrExtOrExt<&Extensions::depthTextureANGLE, &Extensions::depthTextureOES, &Extensions::depth32>, RequireExtOrExtOrExt<&Extensions::depthTextureANGLE, &Extensions::depthTextureOES, &Extensions::depth32>);
     AddDepthStencilFormat(&map, GL_DEPTH24_STENCIL8,      true, 24, 8,  0, GL_DEPTH_STENCIL,   GL_UNSIGNED_INT_24_8,              GL_UNSIGNED_NORMALIZED, RequireESOrExt<3, 0, &Extensions::depthTextureANGLE>,              AlwaysSupported,                                  RequireESOrExtOrExt<3, 0, &Extensions::depthTextureANGLE, &Extensions::packedDepthStencil>, RequireESOrExtOrExt<3, 0, &Extensions::depthTextureANGLE, &Extensions::packedDepthStencil>);

src/tests/gl_tests/DepthStencilFormatsTest.cpp

@@ -64,6 +64,62 @@ class DepthStencilFormatsTestBase : public ANGLETest
         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.get(), 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.get(), 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.get(), 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;
@@ -470,6 +526,27 @@ void main()
     }
 }
 
+// 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, DrawWithDepthStencil)
 {
     GLushort data[16];

src/tests/gl_tests/DepthStencilTest.cpp

@@ -52,8 +52,8 @@ class DepthStencilTest : public ANGLETest
 
         ASSERT_GL_NO_ERROR();
 
-        // Note: GL_DEPTH_COMPONENT24 is not allowed in GLES2.
+        // Note: GL_DEPTH_COMPONENT24 is allowed in GLES2 with GL_OES_depth24 extension.
-        if (getClientMajorVersion() >= 3)
+        if (getClientMajorVersion() >= 3 || IsGLExtensionEnabled("GL_OES_depth24"))
         {
             // Setup Color/Depth FBO with a depth format that's emulated with packed depth/stencil.
             glBindFramebuffer(GL_FRAMEBUFFER, mColorDepthFBO);
@@ -234,7 +234,7 @@ void DepthStencilTest::prepareSingleEmulatedWithPacked()
 // Tests that clearing or rendering into a depth-only format doesn't affect stencil.
 TEST_P(DepthStencilTest, DepthOnlyEmulatedWithPacked)
 {
-    ANGLE_SKIP_TEST_IF(getClientMajorVersion() < 3);
+    ANGLE_SKIP_TEST_IF(getClientMajorVersion() < 3 && !IsGLExtensionEnabled("GL_OES_depth24"));
 
     bindColorDepthFBO();
     prepareSingleEmulatedWithPacked();
@@ -256,6 +256,7 @@ ANGLE_INSTANTIATE_TEST(DepthStencilTest,
                        ES3_OPENGL(),
                        ES2_OPENGLES(),
                        ES3_OPENGLES(),
-                       ES2_VULKAN());
+                       ES2_VULKAN(),
+                       ES3_VULKAN());
 
 }  // anonymous namespace