[Feat] (Diligent, MG_Impl): wire BlitNamedFramebuffer color copy

- Explicit read/draw FBO color attachments resolve to Diligent textures/renderbuffers
- CopyTexture between them for same-size color blits
- Update handoff; 16 Diligent tests pass

HANDOFF_DILIGENT.md

@@ -155,7 +155,7 @@ Verified locally on Turnip Adreno 750:
   - `DrawArraysInstanced` / `DrawElementsInstanced` family
   - Indirect draw CPU fallback: `DrawArraysIndirect`, `DrawElementsIndirect`, `MultiDraw*Indirect`, `*IndirectCount`
   - `ClearBufferfv` / `ClearBufferfi` / `ClearBufferiv` / `ClearBufferuiv` (incl. stencil clear)
-  - `BlitFramebuffer` (same-size color copy between current read/draw FBOs)
+  - `BlitFramebuffer` / `BlitNamedFramebuffer` (same-size color copy between read/draw FBOs)
   - `CopyTexImage2D` / `CopyTexSubImage2D` (whole-color copy fallback)
   - `CopyImageSubData` (whole-texture copy between two texture objects)
   - `GenerateMipmap` (Diligent GPU mip generation on state textures)

MobileGL/MG_Backend/Diligent/BackendObject_Diligent.cpp

@@ -449,6 +449,26 @@ namespace MobileGL::MG_Backend::DiligentBackend {
             }
         }
 
+        void BlitNamedFramebuffer(const SharedPtr<MG_State::GLState::FramebufferObject>& readFramebuffer,
+                                  const SharedPtr<MG_State::GLState::FramebufferObject>& drawFramebuffer,
+                                  GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
+                                  GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
+                                  GLbitfield mask, GLenum filter) {
+            (void)srcX0;
+            (void)srcY0;
+            (void)srcX1;
+            (void)srcY1;
+            (void)dstX0;
+            (void)dstY0;
+            (void)dstX1;
+            (void)dstY1;
+            (void)filter;
+            auto* renderer = GetActiveRenderer();
+            if (renderer != nullptr) {
+                renderer->BlitNamedFramebuffer(readFramebuffer, drawFramebuffer, mask);
+            }
+        }
+
         void CopyTexImage2D(GLenum target, GLint level, GLenum internalformat, GLint x, GLint y,
                             GLsizei width, GLsizei height, GLint border) {
             (void)level;
@@ -662,6 +682,7 @@ namespace MobileGL::MG_Backend::DiligentBackend {
         m_functions.GL.ClearBufferiv = ClearBufferiv;
         m_functions.GL.ClearBufferuiv = ClearBufferuiv;
         m_functions.GL.BlitFramebuffer = BlitFramebuffer;
+        m_functions.GL.BlitNamedFramebuffer = BlitNamedFramebuffer;
         m_functions.GL.CopyTexImage2D = CopyTexImage2D;
         m_functions.GL.CopyTexSubImage2D = CopyTexSubImage2D;
         m_functions.GL.CopyImageSubData = CopyImageSubData;

MobileGL/MG_Backend/Diligent/Renderer/DiligentRenderer.cpp

@@ -1712,6 +1712,63 @@ void main()
         m_pContext->UnmapTextureSubresource(pStaging, 0, 0);
     }
 
+    void DiligentRenderer::BlitNamedFramebuffer(
+        const SharedPtr<MG_State::GLState::FramebufferObject>& readFbo,
+        const SharedPtr<MG_State::GLState::FramebufferObject>& drawFbo,
+        GLbitfield mask) {
+        if (!m_initialized || !m_pContext || (mask & GL_COLOR_BUFFER_BIT) == 0) {
+            return;
+        }
+
+        ::Diligent::RefCntAutoPtr<::Diligent::ITexture> pSrcTexture = m_pColorTarget;
+        ::Diligent::RefCntAutoPtr<::Diligent::ITexture> pDstTexture = m_pColorTarget;
+        if (readFbo && !readFbo->IsDefaultFramebuffer()) {
+            auto readBuffer = readFbo->GetReadBuffer();
+            if (readBuffer == FramebufferAttachmentType::None) {
+                readBuffer = FramebufferAttachmentType::Color0;
+            }
+            const auto& att = readFbo->GetAttachment(readBuffer);
+            if (att.IsTexture() && SyncTexture(*att.GetTexture()) != nullptr) {
+                auto it = m_textureCache.find(att.GetTexture()->GetLifetimeId());
+                if (it != m_textureCache.end() && it->second.Texture) {
+                    pSrcTexture = it->second.Texture;
+                }
+            } else if (att.IsRenderbuffer() && SyncRenderbuffer(*att.GetRenderbuffer()) != nullptr) {
+                auto it = m_renderbufferCache.find(att.GetRenderbuffer()->GetExternalIndex());
+                if (it != m_renderbufferCache.end() && it->second.Texture) {
+                    pSrcTexture = it->second.Texture;
+                }
+            }
+        }
+        if (drawFbo && !drawFbo->IsDefaultFramebuffer()) {
+            for (const auto candidate : drawFbo->GetDrawBuffers()) {
+                if (candidate == FramebufferAttachmentType::None) {
+                    continue;
+                }
+                const auto& att = drawFbo->GetAttachment(candidate);
+                if (att.IsTexture() && SyncTexture(*att.GetTexture()) != nullptr) {
+                    auto it = m_textureCache.find(att.GetTexture()->GetLifetimeId());
+                    if (it != m_textureCache.end() && it->second.Texture) {
+                        pDstTexture = it->second.Texture;
+                    }
+                } else if (att.IsRenderbuffer() && SyncRenderbuffer(*att.GetRenderbuffer()) != nullptr) {
+                    auto it = m_renderbufferCache.find(att.GetRenderbuffer()->GetExternalIndex());
+                    if (it != m_renderbufferCache.end() && it->second.Texture) {
+                        pDstTexture = it->second.Texture;
+                    }
+                }
+                break;
+            }
+        }
+        if (!pSrcTexture || !pDstTexture || pSrcTexture == pDstTexture) {
+            return;
+        }
+        ::Diligent::CopyTextureAttribs copyAttribs(
+            pSrcTexture, ::Diligent::RESOURCE_STATE_TRANSITION_MODE_TRANSITION,
+            pDstTexture, ::Diligent::RESOURCE_STATE_TRANSITION_MODE_TRANSITION);
+        m_pContext->CopyTexture(copyAttribs);
+    }
+
     void DiligentRenderer::BlitFramebuffer(GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
                                        GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
                                        GLbitfield mask, GLenum filter) {

MobileGL/MG_Backend/Diligent/Renderer/DiligentRenderer.h

@@ -36,6 +36,7 @@ namespace MobileGL::MG_State::GLState {
     class SamplerObject;
     class ProgramObject;
     class RenderbufferObject;
+    class FramebufferObject;
 }
 
 namespace MobileGL::MG_Backend::DiligentBackend {
@@ -65,6 +66,9 @@ namespace MobileGL::MG_Backend::DiligentBackend {
         void BlitFramebuffer(GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
                              GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
                              GLbitfield mask, GLenum filter);
+        void BlitNamedFramebuffer(const SharedPtr<MG_State::GLState::FramebufferObject>& readFbo,
+                                  const SharedPtr<MG_State::GLState::FramebufferObject>& drawFbo,
+                                  GLbitfield mask);
         void CopyReadFramebufferToTexture(MG_State::GLState::ITextureObject& dst);
         void CopyTextureSubData(MG_State::GLState::ITextureObject& src, MG_State::GLState::ITextureObject& dst);
         void GenerateMipmap(MG_State::GLState::ITextureObject& texture);