GL: enable cube map 3D image up/download on all platforms.

There were slice-by-slice workarounds for certain drivers already, so
why not reuse them to make this functionality available everywhere.

doc/changelog.dox

@@ -220,6 +220,13 @@ See also:
 -   The @ref GL::Context class got significantly optimized in terms of compile
     time, header size and runtime as well, significantly reducing the amount of
     allocations done at startup.
+-   To make working with cube map images easier,
+    @ref GL::CubeMapTexture::setSubImage() and
+    @ref GL::CubeMapTexture::subImage() taking 3D images are now exposed on all
+    platforms, not just desktop OpenGL 4.5+, with a fall back to slice-by-slice
+    upload/download where needed. The compressed variant is still only GL 4.5+,
+    as that needs the @ref CompressedImageView APIs to be aware of compression
+    format properties, which isn't implemented yet.
 -   Added @ref GL::Framebuffer::Status::IncompleteDimensions for ES2. This enum
     isn't available on ES3 or desktop GL, but NVidia drivers are known to emit
     it, which is why it got added.

src/Magnum/GL/CubeMapTexture.cpp

@@ -493,16 +493,24 @@ CompressedBufferImage3D CubeMapTexture::compressedSubImage(const Int level, cons
     compressedSubImage(level, range, image, usage);
     return std::move(image);
 }
+#endif
 
 CubeMapTexture& CubeMapTexture::setSubImage(const Int level, const Vector3i& offset, const ImageView3D& image) {
     createIfNotAlready();
 
+    #ifndef MAGNUM_TARGET_GLES2
     Buffer::unbindInternal(Buffer::TargetHint::PixelUnpack);
+    #endif
     Context::current().state().renderer.applyPixelStorageUnpack(image.storage());
-    (this->*Context::current().state().texture.cubeSubImage3DImplementation)(level, offset, image.size(), pixelFormat(image.format()), pixelType(image.format(), image.formatExtra()), image.data(), image.storage());
+    (this->*Context::current().state().texture.cubeSubImage3DImplementation)(level, offset, image.size(), pixelFormat(image.format()), pixelType(image.format(), image.formatExtra()), image.data()
+        #ifdef MAGNUM_TARGET_GLES2
+        + Magnum::Implementation::pixelStorageSkipOffset(image)
+        #endif
+        , image.storage());
     return *this;
 }
 
+#ifndef MAGNUM_TARGET_GLES2
 CubeMapTexture& CubeMapTexture::setSubImage(const Int level, const Vector3i& offset, BufferImage3D& image) {
     createIfNotAlready();
 
@@ -511,7 +519,9 @@ CubeMapTexture& CubeMapTexture::setSubImage(const Int level, const Vector3i& off
     (this->*Context::current().state().texture.cubeSubImage3DImplementation)(level, offset, image.size(), image.format(), image.type(), nullptr, image.storage());
     return *this;
 }
+#endif
 
+#ifndef MAGNUM_TARGET_GLES
 CubeMapTexture& CubeMapTexture::setCompressedSubImage(const Int level, const Vector3i& offset, const CompressedImageView3D& image) {
     createIfNotAlready();
 
@@ -689,13 +699,13 @@ void CubeMapTexture::subImageImplementationDSASliceBySlice(const GLint level, co
     for(Int i = 0; i != size.z(); ++i)
         subImageImplementationDSA(level, {offset.xy(), offset.z() + i}, {size.xy(), 1}, format, type, static_cast<const char*>(data) + stride*i, storage);
 }
+#endif
 
 void CubeMapTexture::subImageImplementationSliceBySlice(const GLint level, const Vector3i& offset, const Vector3i& size, const PixelFormat format, const PixelType type, const GLvoid* const data, const PixelStorage& storage) {
     const std::size_t stride = std::get<1>(storage.dataProperties(pixelSize(format, type), size)).xy().product();
     for(Int i = 0; i != size.z(); ++i)
         subImageImplementationDefault(CubeMapCoordinate(GL_TEXTURE_CUBE_MAP_POSITIVE_X + i), level, offset.xy(), size.xy(), format, type, static_cast<const char*>(data) + stride*i);
 }
-#endif
 
 void CubeMapTexture::subImageImplementationDefault(const CubeMapCoordinate coordinate, const GLint level, const Vector2i& offset, const Vector2i& size, const PixelFormat format, const PixelType type, const GLvoid* const data) {
     bindInternal();

src/Magnum/GL/CubeMapTexture.h

@@ -559,10 +559,19 @@ class MAGNUM_GL_EXPORT CubeMapTexture: public AbstractTexture {
          * @ref imageSize(). The storage is not reallocated if it is large
          * enough to contain the new data.
          *
-         * The operation is protected from buffer overflow.
+         * If @gl_extension{ARB,direct_state_access} (part of OpenGL 4.5) is
-         * @see @fn_gl2{GetTextureLevelParameter,GetTexLevelParameter} with
+         * not available, the texture is bound before the operation (if not
-         *      @def_gl{TEXTURE_WIDTH}, @def_gl{TEXTURE_HEIGHT}, then
+         * already) and the image is downloaded slice by slice. If either
-         *      @fn_gl{PixelStore}, then @fn_gl2_keyword{GetTextureImage,GetTexImage}
+         * @gl_extension{ARB,get_texture_sub_image} or
+         * @gl_extension{ARB,robustness} is available, the operation is
+         * protected from buffer overflow.
+         * @see @fn_gl2{GetTextureLevelParameter,GetTexLevelParameter},
+         *      eventually @fn_gl{ActiveTexture}, @fn_gl{BindTexture} and
+         *      @fn_gl{GetTexLevelParameter} with @def_gl{TEXTURE_WIDTH},
+         *      @def_gl{TEXTURE_HEIGHT}, then @fn_gl{PixelStore}, then
+         *      @fn_gl2_keyword{GetTextureImage,GetTexImage},
+         *      @fn_gl_extension_keyword{GetnTexImage,ARB,robustness},
+         *      eventually @fn_gl_keyword{GetTexImage}
          * @requires_gl45 Extension @gl_extension{ARB,direct_state_access}
          * @requires_gl Texture image queries are not available in OpenGL ES or
          *      WebGL. See @ref Framebuffer::read() or @ref DebugTools::textureSubImage()
@@ -1024,7 +1033,6 @@ class MAGNUM_GL_EXPORT CubeMapTexture: public AbstractTexture {
         }
         #endif
 
-        #ifndef MAGNUM_TARGET_GLES
         /**
          * @brief Set image subdata
          * @param level             Mip level
@@ -1033,29 +1041,41 @@ class MAGNUM_GL_EXPORT CubeMapTexture: public AbstractTexture {
          *      @ref Trade::ImageData3D
          * @return Reference to self (for method chaining)
          *
-         * @see @ref setStorage(), @fn_gl2{TextureSubImage3D,TexSubImage3D}
+         * If @gl_extension{ARB,direct_state_access} (part of OpenGL 4.5) is
-         * @requires_gl45 Extension @gl_extension{ARB,direct_state_access}
+         * not available, the texture is bound before the operation (if not
-         * @requires_gl In OpenGL ES and WebGL you need to set image for each
+         * already) and the image is uploaded slice by slice.
-         *      face separately.
+         * @see @ref setStorage(), @fn_gl2{TextureSubImage3D,TexSubImage3D},
+         *      eventually @fn_gl{ActiveTexture}, @fn_gl{BindTexture} and
+         *      @fn_gl_keyword{TexSubImage2D}
+         * @requires_gles30 Extension @gl_extension{EXT,unpack_subimage}/
+         *      @gl_extension{NV,pack_subimage} in OpenGL ES 2.0 if
+         *      @ref PixelStorage::rowLength() is set to a non-zero value.
+         * @requires_webgl20 Non-zero @ref PixelStorage::rowLength() is not
+         *      supported in WebGL 1.0.
          */
         CubeMapTexture& setSubImage(Int level, const Vector3i& offset, const ImageView3D& image);
 
+        #ifndef MAGNUM_TARGET_GLES2
         /** @overload
-         * @requires_gl45 Extension @gl_extension{ARB,direct_state_access}
+         * @requires_gles30 Pixel buffer objects are not available in OpenGL ES
-         * @requires_gl In OpenGL ES and WebGL you need to set image for each
+         *      2.0.
-         *      face separately.
+         * @requires_webgl20 Pixel buffer objects are not available in WebGL
+         *      1.0.
          */
         CubeMapTexture& setSubImage(Int level, const Vector3i& offset, BufferImage3D& image);
 
         /** @overload
-         * @requires_gl45 Extension @gl_extension{ARB,direct_state_access}
+         * @requires_gles30 Pixel buffer objects are not available in OpenGL ES
-         * @requires_gl In OpenGL ES and WebGL you need to set image for each
+         *      2.0.
-         *      face separately.
+         * @requires_webgl20 Pixel buffer objects are not available in WebGL
+         *      1.0.
          */
         CubeMapTexture& setSubImage(Int level, const Vector3i& offset, BufferImage3D&& image) {
             return setSubImage(level, offset, image);
         }
+        #endif
 
+        #ifndef MAGNUM_TARGET_GLES
         /**
          * @brief Set compressed image subdata
          * @param level             Mip level
@@ -1248,8 +1268,8 @@ class MAGNUM_GL_EXPORT CubeMapTexture: public AbstractTexture {
         #ifndef MAGNUM_TARGET_GLES
         void MAGNUM_GL_LOCAL subImageImplementationDSA(GLint level, const Vector3i& offset, const Vector3i& size, PixelFormat format, PixelType type, const GLvoid* data, const PixelStorage&);
         void MAGNUM_GL_LOCAL subImageImplementationDSASliceBySlice(GLint level, const Vector3i& offset, const Vector3i& size, PixelFormat format, PixelType type, const GLvoid* data, const PixelStorage&);
-        void MAGNUM_GL_LOCAL subImageImplementationSliceBySlice(GLint level, const Vector3i& offset, const Vector3i& size, PixelFormat format, PixelType type, const GLvoid* data, const PixelStorage&);
         #endif
+        void MAGNUM_GL_LOCAL subImageImplementationSliceBySlice(GLint level, const Vector3i& offset, const Vector3i& size, PixelFormat format, PixelType type, const GLvoid* data, const PixelStorage&);
 
         void MAGNUM_GL_LOCAL subImageImplementationDefault(CubeMapCoordinate coordinate, GLint level, const Vector2i& offset, const Vector2i& size, PixelFormat format, PixelType type, const GLvoid* data);
         #ifndef MAGNUM_TARGET_GLES

src/Magnum/GL/Implementation/TextureState.cpp

@@ -348,6 +348,9 @@ TextureState::TextureState(Context& context,
         getCubeImage3DImplementation = &CubeMapTexture::getImageImplementationSliceBySlice;
     else
     #endif
+    if(context.isExtensionSupported<Extensions::ARB::direct_state_access>()) {
+        getCubeImage3DImplementation = &CubeMapTexture::getImageImplementationDSA;
+    } else {
         getCubeImage3DImplementation = &CubeMapTexture::getImageImplementationSliceBySlice;
     }
     #endif
@@ -500,14 +503,14 @@ TextureState::TextureState(Context& context,
     /* SVGA3D and Intel workaround for cube map texture upload. Overrides the
        DSA / non-DSA function pointers set above. */
     if((context.detectedDriver() & Context::DetectedDriver::Svga3D) &&
-       !context.isDriverWorkaroundDisabled("svga3d-texture-upload-slice-by-slice"_s)) {
+        context.isExtensionSupported<Extensions::ARB::direct_state_access>() &&
-        if(context.isExtensionSupported<Extensions::ARB::direct_state_access>()) {
+        !context.isDriverWorkaroundDisabled("svga3d-texture-upload-slice-by-slice"_s)
-            cubeSubImage3DImplementation = &CubeMapTexture::subImageImplementationDSASliceBySlice;
+    ) {
-        } else {
+        cubeSubImage3DImplementation = &CubeMapTexture::subImageImplementationDSASliceBySlice;
-            cubeSubImage3DImplementation = &CubeMapTexture::subImageImplementationSliceBySlice;
-        }
     } else if((context.detectedDriver() & Context::DetectedDriver::IntelWindows) &&
-       !context.isDriverWorkaroundDisabled("intel-windows-broken-dsa-for-cubemaps"_s)) {
+        context.isExtensionSupported<Extensions::ARB::direct_state_access>() &&
+        !context.isDriverWorkaroundDisabled("intel-windows-broken-dsa-for-cubemaps"_s)
+    ) {
         cubeSubImage3DImplementation = &CubeMapTexture::subImageImplementationSliceBySlice;
     }
     #ifdef CORRADE_TARGET_WINDOWS
@@ -523,10 +526,10 @@ TextureState::TextureState(Context& context,
     else if(context.isExtensionSupported<Extensions::ARB::direct_state_access>()) {
         cubeSubImage3DImplementation = &CubeMapTexture::subImageImplementationDSA;
     } else
+    #endif
     {
         cubeSubImage3DImplementation = &CubeMapTexture::subImageImplementationSliceBySlice;
     }
-    #endif
 
     #if defined(CORRADE_TARGET_APPLE) && !defined(MAGNUM_TARGET_GLES)
     if(!context.isDriverWorkaroundDisabled("apple-buffer-texture-unbind-on-buffer-modify"_s)) {

src/Magnum/GL/Implementation/TextureState.h

@@ -125,8 +125,8 @@ struct TextureState {
     void(CubeMapTexture::*getCubeImage3DImplementation)(GLint, const Vector3i&, PixelFormat, PixelType, std::size_t, GLvoid*, const PixelStorage&);
     void(CubeMapTexture::*getCompressedCubeImage3DImplementation)(GLint, const Vector2i&, std::size_t, std::size_t, GLvoid*);
     void(CubeMapTexture::*getCompressedCubeImageImplementation)(CubeMapCoordinate, GLint, const Vector2i&, std::size_t, GLvoid*);
-    void(CubeMapTexture::*cubeSubImage3DImplementation)(GLint, const Vector3i&, const Vector3i&, PixelFormat, PixelType, const GLvoid*, const PixelStorage&);
     #endif
+    void(CubeMapTexture::*cubeSubImage3DImplementation)(GLint, const Vector3i&, const Vector3i&, PixelFormat, PixelType, const GLvoid*, const PixelStorage&);
     void(CubeMapTexture::*cubeSubImageImplementation)(CubeMapCoordinate, GLint, const Vector2i&, const Vector2i&, PixelFormat, PixelType, const GLvoid*);
     void(CubeMapTexture::*cubeCompressedSubImageImplementation)(CubeMapCoordinate, GLint, const Vector2i&, const Vector2i&, CompressedPixelFormat, const GLvoid*, GLsizei);
 

src/Magnum/GL/Test/CubeMapTextureGLTest.cpp

@@ -128,15 +128,21 @@ struct CubeMapTextureGLTest: OpenGLTester {
     void compressedSubImageQueryBuffer();
     #endif
 
-    #ifndef MAGNUM_TARGET_GLES
     void image3D();
+    #ifndef MAGNUM_TARGET_GLES2
     void image3DBuffer();
+    #endif
+    #ifndef MAGNUM_TARGET_GLES
     void image3DQueryView();
     void image3DQueryViewNullptr();
     void image3DQueryViewBadSize();
+    #endif
 
+    #ifndef MAGNUM_TARGET_GLES
     void compressedImage3D();
+    #ifndef MAGNUM_TARGET_GLES2
     void compressedImage3DBuffer();
+    #endif
     void compressedImage3DQueryView();
     void compressedImage3DQueryViewNullptr();
     void compressedImage3DQueryViewBadSize();
@@ -216,7 +222,6 @@ const struct {
     #endif
 };
 
-#ifndef MAGNUM_TARGET_GLES
 constexpr UnsignedByte FullData[]{
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 
@@ -253,6 +258,7 @@ const struct {
     #endif
 };
 
+#ifndef MAGNUM_TARGET_GLES
 /* Just 4x4 0x00 - 0x3f compressed using RGBA DXT3 by the driver, repeated
    six times */
 constexpr UnsignedByte CompressedFullData[]{
@@ -348,13 +354,17 @@ CubeMapTextureGLTest::CubeMapTextureGLTest() {
               &CubeMapTextureGLTest::imageQueryViewBadSize});
     #endif
 
-    #ifndef MAGNUM_TARGET_GLES
     addInstancedTests({
         &CubeMapTextureGLTest::image3D,
+        #ifndef MAGNUM_TARGET_GLES2
         &CubeMapTextureGLTest::image3DBuffer,
-        &CubeMapTextureGLTest::image3DQueryView},
+        #endif
-        Containers::arraySize(FullPixelStorageData));
+        #ifndef MAGNUM_TARGET_GLES
+        &CubeMapTextureGLTest::image3DQueryView
+        #endif
+        }, Containers::arraySize(FullPixelStorageData));
 
+    #ifndef MAGNUM_TARGET_GLES
     addTests({&CubeMapTextureGLTest::image3DQueryViewNullptr,
               &CubeMapTextureGLTest::image3DQueryViewBadSize});
     #endif
@@ -1735,21 +1745,24 @@ void CubeMapTextureGLTest::compressedSubImageQueryBuffer() {
 }
 #endif
 
-#ifndef MAGNUM_TARGET_GLES
 void CubeMapTextureGLTest::image3D() {
     setTestCaseDescription(FullPixelStorageData[testCaseInstanceId()].name);
 
-    if(!Context::current().isExtensionSupported<Extensions::ARB::direct_state_access>())
+    #if !(defined(MAGNUM_TARGET_GLES2) && defined(MAGNUM_TARGET_WEBGL))
-        CORRADE_SKIP(Extensions::ARB::direct_state_access::string() << "is not supported.");
+    constexpr TextureFormat format = TextureFormat::RGBA8;
+    #else
+    constexpr TextureFormat format = TextureFormat::RGBA;
+    #endif
 
     CubeMapTexture texture;
-    texture.setStorage(1, TextureFormat::RGBA8, Vector2i{2, 2})
+    texture.setStorage(1, format, Vector2i{2, 2})
         .setSubImage(0, {}, ImageView3D{
             PixelFormat::RGBA, PixelType::UnsignedByte, {2, 2, 6},
             FullPixelStorageData[testCaseInstanceId()].data});
 
     MAGNUM_VERIFY_NO_GL_ERROR();
 
+    #ifndef MAGNUM_TARGET_GLES
     Image3D image = texture.image(0,
         {FullPixelStorageData[testCaseInstanceId()].storage, PixelFormat::RGBA, PixelType::UnsignedByte});
 
@@ -1763,14 +1776,13 @@ void CubeMapTextureGLTest::image3D() {
             FullPixelStorageData[testCaseInstanceId()].data,
             TestSuite::Compare::Container);
     }
+    #endif
 }
 
+#ifndef MAGNUM_TARGET_GLES2
 void CubeMapTextureGLTest::image3DBuffer() {
     setTestCaseDescription(FullPixelStorageData[testCaseInstanceId()].name);
 
-    if(!Context::current().isExtensionSupported<Extensions::ARB::direct_state_access>())
-        CORRADE_SKIP(Extensions::ARB::direct_state_access::string() << "is not supported.");
-
     CubeMapTexture texture;
     texture.setStorage(1, TextureFormat::RGBA8, Vector2i{2})
         .setSubImage(0, {}, BufferImage3D{
@@ -1780,6 +1792,7 @@ void CubeMapTextureGLTest::image3DBuffer() {
 
     MAGNUM_VERIFY_NO_GL_ERROR();
 
+    #ifndef MAGNUM_TARGET_GLES
     BufferImage3D image = texture.image(0,
         {FullPixelStorageData[testCaseInstanceId()].storage, PixelFormat::RGBA,
             PixelType::UnsignedByte}, BufferUsage::StaticRead);
@@ -1794,14 +1807,14 @@ void CubeMapTextureGLTest::image3DBuffer() {
         CORRADE_COMPARE_AS(Containers::arrayCast<UnsignedByte>(imageData).suffix(FullPixelStorageData[testCaseInstanceId()].offset),
             FullPixelStorageData[testCaseInstanceId()].data, TestSuite::Compare::Container);
     }
+    #endif
 }
+#endif
 
+#ifndef MAGNUM_TARGET_GLES
 void CubeMapTextureGLTest::image3DQueryView() {
     setTestCaseDescription(FullPixelStorageData[testCaseInstanceId()].name);
 
-    if(!Context::current().isExtensionSupported<Extensions::ARB::direct_state_access>())
-        CORRADE_SKIP(Extensions::ARB::direct_state_access::string() << "is not supported.");
-
     CubeMapTexture texture;
     texture.setStorage(1, TextureFormat::RGBA8, Vector2i{2, 2})
         .setSubImage(0, {}, ImageView3D{
@@ -1864,7 +1877,9 @@ void CubeMapTextureGLTest::image3DQueryViewBadSize() {
     texture.image(0, image);
     CORRADE_COMPARE(out.str(), "GL::CubeMapTexture::image(): expected image view size Vector(2, 2, 6) but got Vector(2, 1, 6)\n");
 }
+#endif
 
+#ifndef MAGNUM_TARGET_GLES
 void CubeMapTextureGLTest::compressedImage3D() {
     setTestCaseDescription(CompressedFullPixelStorageData[testCaseInstanceId()].name);