GL: new "intel-windows-broken-dsa-for-cubemaps" workaround.

Fixes everything related to cube maps when ARB_DSA is used.

doc/changelog.dox

@@ -71,10 +71,16 @@ See also:
     @ref opengl-workarounds for more information). This pseudo-extension can be
     also explicitly disabled using the usual `--magnum-disable-extensions`
     @ref GL-Context-command-line "command-line option" for testing purposes.
--   New @cpp "intel-windows-buggy-dsa-bufferdata-for-index-buffers" @ce
-    workaround for a synchronization bug in the Intel Windows drivers when
-    @ref GL::Buffer::setData() is followed by @ref GL::Mesh::setIndexBuffer()
-    when @gl_extension{ARB,direct_state_access} is used
+-   An assorted collection of workarounds for Intel Windows drivers "fixing"
+    various issues related to @gl_extension{ARB,direct_state_access} by using a
+    non-DSA code path in the affected cases --- see
+    @ref opengl-workarounds for more information:
+    -   @cpp "intel-windows-buggy-dsa-bufferdata-for-index-buffers" @ce
+        fixing a nasty hard-to-reproduce synchronization bug when
+        @ref GL::Buffer::setData() is followed by
+        @ref GL::Mesh::setIndexBuffer()
+    -   @cpp "intel-windows-broken-dsa-for-cubemaps" @ce fixing everything
+        about @ref GL::CubeMapTexture (see [mosra/magnum-examples#55](https://github.com/mosra/magnum-examples/issues/55))
 -   New `--magnum-gpu-validation` @ref GL-Context-command-line "command-line option"
     and a corresponding environment variable to conveniently enable
     @gl_extension{KHR,debug} debug output

src/Magnum/GL/Implementation/FramebufferState.cpp

@@ -76,7 +76,6 @@ FramebufferState::FramebufferState(Context& context, std::vector<std::string>& e
 
         copySub1DImplementation = &AbstractFramebuffer::copySub1DImplementationDSA;
         copySub2DImplementation = &AbstractFramebuffer::copySub2DImplementationDSA;
-        copySubCubeMapImplementation = &AbstractFramebuffer::copySubCubeMapImplementationDSA;
         copySub3DImplementation = &AbstractFramebuffer::copySub3DImplementationDSA;
 
         renderbufferImplementation = &Framebuffer::renderbufferImplementationDSA;
@@ -86,7 +85,6 @@ FramebufferState::FramebufferState(Context& context, std::vector<std::string>& e
            function to specify cube map face */
         texture2DImplementation = &Framebuffer::texture2DImplementationDSA;
         textureImplementation = &Framebuffer::textureImplementationDSA;
-        textureCubeMapImplementation = &Framebuffer::textureCubeMapImplementationDSA;
         textureLayerImplementation = &Framebuffer::textureLayerImplementationDSA;
 
         renderbufferStorageImplementation = &Renderbuffer::storageImplementationDSA;
@@ -117,7 +115,6 @@ FramebufferState::FramebufferState(Context& context, std::vector<std::string>& e
         copySub1DImplementation = &AbstractFramebuffer::copySub1DImplementationDefault;
         #endif
         copySub2DImplementation = &AbstractFramebuffer::copySub2DImplementationDefault;
-        copySubCubeMapImplementation = &AbstractFramebuffer::copySub2DImplementationDefault;
         #if !(defined(MAGNUM_TARGET_WEBGL) && defined(MAGNUM_TARGET_GLES2))
         copySub3DImplementation = &AbstractFramebuffer::copySub3DImplementationDefault;
         #endif
@@ -131,7 +128,6 @@ FramebufferState::FramebufferState(Context& context, std::vector<std::string>& e
         #ifndef MAGNUM_TARGET_GLES
         textureImplementation = &Framebuffer::textureImplementationDefault;
         #endif
-        textureCubeMapImplementation = &Framebuffer::texture2DImplementationDefault;
         #if !(defined(MAGNUM_TARGET_WEBGL) && defined(MAGNUM_TARGET_GLES2))
         textureLayerImplementation = &Framebuffer::textureLayerImplementationDefault;
         #endif
@@ -139,6 +135,26 @@ FramebufferState::FramebufferState(Context& context, std::vector<std::string>& e
         renderbufferStorageImplementation = &Renderbuffer::storageImplementationDefault;
     }
 
+    /* DSA/non-DSA implementation for cubemaps, because Intel Windows drivers
+       have to be broken in a special way */
+    #ifndef MAGNUM_TARGET_GLES
+    if(context.isExtensionSupported<Extensions::ARB::direct_state_access>()
+        #ifdef CORRADE_TARGET_WINDOWS
+        && (!(context.detectedDriver() & Context::DetectedDriver::IntelWindows) ||
+            context.isDriverWorkaroundDisabled("intel-windows-broken-dsa-for-cubemaps"))
+        #endif
+    ) {
+        /* Extension name added above */
+
+        copySubCubeMapImplementation = &AbstractFramebuffer::copySubCubeMapImplementationDSA;
+        textureCubeMapImplementation = &Framebuffer::textureCubeMapImplementationDSA;
+    } else
+    #endif
+    {
+        copySubCubeMapImplementation = &AbstractFramebuffer::copySub2DImplementationDefault;
+        textureCubeMapImplementation = &Framebuffer::texture2DImplementationDefault;
+    }
+
     /* Framebuffer texture attachment on ES3 */
     #if defined(MAGNUM_TARGET_GLES) && !defined(MAGNUM_TARGET_WEBGL) && !defined(MAGNUM_TARGET_GLES2)
     if(context.isVersionSupported(Version::GLES320))

src/Magnum/GL/Implementation/TextureState.cpp

@@ -130,10 +130,6 @@ TextureState::TextureState(Context& context, std::vector<std::string>& extension
         setBufferImplementation = &BufferTexture::setBufferImplementationDSA;
         setBufferRangeImplementation = &BufferTexture::setBufferRangeImplementationDSA;
 
-        getCubeLevelParameterivImplementation = &CubeMapTexture::getLevelParameterImplementationDSA;
-        cubeSubImageImplementation = &CubeMapTexture::subImageImplementationDSA;
-        cubeCompressedSubImageImplementation = &CubeMapTexture::compressedSubImageImplementationDSA;
-
     } else
     #endif
     {
@@ -166,7 +162,25 @@ TextureState::TextureState(Context& context, std::vector<std::string>& extension
         setBufferImplementation = &BufferTexture::setBufferImplementationDefault;
         setBufferRangeImplementation = &BufferTexture::setBufferRangeImplementationDefault;
         #endif
+    }
+
+    /* DSA/non-DSA implementation for cubemaps, because Intel Windows drivers
+       have to be broken in a special way */
+    #ifndef MAGNUM_TARGET_GLES
+    if(context.isExtensionSupported<Extensions::ARB::direct_state_access>()
+        #ifdef CORRADE_TARGET_WINDOWS
+        && (!(context.detectedDriver() & Context::DetectedDriver::IntelWindows) ||
+            context.isDriverWorkaroundDisabled("intel-windows-broken-dsa-for-cubemaps"))
+        #endif
+    ) {
+        /* Extension name added above */
 
+        getCubeLevelParameterivImplementation = &CubeMapTexture::getLevelParameterImplementationDSA;
+        cubeSubImageImplementation = &CubeMapTexture::subImageImplementationDSA;
+        cubeCompressedSubImageImplementation = &CubeMapTexture::compressedSubImageImplementationDSA;
+    } else
+    #endif
+    {
         #if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
         getCubeLevelParameterivImplementation = &CubeMapTexture::getLevelParameterImplementationDefault;
         #endif
@@ -222,10 +236,15 @@ TextureState::TextureState(Context& context, std::vector<std::string>& extension
         if(context.isExtensionSupported<Extensions::ARB::direct_state_access>())
             getCubeLevelCompressedImageSizeImplementation = &CubeMapTexture::getLevelCompressedImageSizeImplementationDSANonImmutableWorkaround;
         else getCubeLevelCompressedImageSizeImplementation = &CubeMapTexture::getLevelCompressedImageSizeImplementationDefaultImmutableWorkaround;
-    } else {
-        if(context.isExtensionSupported<Extensions::ARB::direct_state_access>())
+    } else if(context.isExtensionSupported<Extensions::ARB::direct_state_access>()
+        #ifdef CORRADE_TARGET_WINDOWS
+        && (!(context.detectedDriver() & Context::DetectedDriver::IntelWindows) ||
+            context.isDriverWorkaroundDisabled("intel-windows-broken-dsa-for-cubemaps"))
+        #endif
+    ) {
         getCubeLevelCompressedImageSizeImplementation = &CubeMapTexture::getLevelCompressedImageSizeImplementationDSA;
-        else getCubeLevelCompressedImageSizeImplementation = &CubeMapTexture::getLevelCompressedImageSizeImplementationDefault;
+    } else {
+        getCubeLevelCompressedImageSizeImplementation = &CubeMapTexture::getLevelCompressedImageSizeImplementationDefault;
     }
 
     /* Image retrieval implementation */

src/Magnum/GL/Implementation/driverSpecific.cpp

@@ -210,6 +210,14 @@ namespace {
            Reproducible with the 2019.01 ImGui example, unfortunately I was not
            able to create a standalone minimal repro case. */
         "intel-windows-buggy-dsa-bufferdata-for-index-buffers",
+
+        /* ARB_direct_state_access implementation on Intel Windows drivers has
+           broken *everything* related to cube map textures (but not cube map
+           arrays) -- data upload, data queries, framebuffer attachment,
+           framebuffer copies, all complaining about "Wrong <func> 6 provided
+           for <target> 34067" (GL_TEXTURE_CUBE_MAP is 34067). Using the
+            non-DSA code path as a workaround. */
+        "intel-windows-broken-dsa-for-cubemaps",
         #endif
 
         #ifndef MAGNUM_TARGET_GLES