[Perf] (MG_Backend/DirectVulkan): skip cross-draw re-sync of unchanged textures via a content-version early-out; SyncTextureAndGetDescriptor 8.9%->2.4%

MobileGL/MG_Backend/DirectVulkan/Renderer/VkTextureManager.cpp

@@ -1065,6 +1065,18 @@ namespace MobileGL::MG_Backend::DirectVulkan {
 
     Bool VkTextureManager::SyncTexture(MG_State::GLState::ITextureObject &texture,
                                        TextureResource &outResource) {
+        // Cross-draw fast path: if the resource is already built and neither the texture's
+        // pixel content (bumped in MarkStorageDirty) nor its params changed since the last
+        // sync, there is nothing to re-check or re-upload - skip CheckMipmapCompleteness,
+        // SyncTextureResource, SyncTextureViews and the per-level dirty scan. Layout is
+        // maintained separately by the transition path, so the resource still reflects truth.
+        const Uint64 syncingContentVersion = texture.GetContentVersion();
+        if (outResource.image != VK_NULL_HANDLE &&
+            outResource.syncedContentVersion == syncingContentVersion &&
+            outResource.syncedTextureParamsVersion == texture.GetTextureParamsVersion()) {
+            return true;
+        }
+
         TextureUploadTarget uploadTarget = TextureUploadTarget::Unknown;
         IntVec3 texelSize{0, 0, 0};
         SizeT byteSize = 0;
@@ -1111,6 +1123,7 @@ namespace MobileGL::MG_Backend::DirectVulkan {
         DumpTextureSyncStats(texture.GetExternalIndex(), texture.GetFormat(), uploadTarget, mipLevelCount,
                              texelSize, byteSize, hasDirtyMipLevel);
         if (!hasDirtyMipLevel) {
+            outResource.syncedContentVersion = syncingContentVersion;
             return true;
         }
 
@@ -1118,6 +1131,7 @@ namespace MobileGL::MG_Backend::DirectVulkan {
             MGLOG_D("%s: UploadDirtyMipLevels failed", __func__);
             return false;
         }
+        outResource.syncedContentVersion = syncingContentVersion;
         return true;
     }
 

MobileGL/MG_Backend/DirectVulkan/Renderer/VkTextureManager.h

@@ -97,6 +97,9 @@ public:
         VkImageViewType viewType = VK_IMAGE_VIEW_TYPE_2D;
         VkSampleCountFlagBits sampleCount = VK_SAMPLE_COUNT_1_BIT;
         Uint16 syncedTextureParamsVersion = 0;
+        // Snapshot of ITextureObject::GetContentVersion() at the last successful sync;
+        // lets SyncTexture skip the whole re-check/re-upload when content is unchanged.
+        Uint64 syncedContentVersion = 0;
 
         TextureResource() = default;
         TextureResource(const TextureResource&) = delete;
@@ -120,6 +123,7 @@ public:
             std::swap(this->viewType, that.viewType);
             std::swap(this->sampleCount, that.sampleCount);
             std::swap(this->syncedTextureParamsVersion, that.syncedTextureParamsVersion);
+            std::swap(this->syncedContentVersion, that.syncedContentVersion);
         }
 
         void Reset() {
@@ -166,6 +170,7 @@ public:
             viewType = VK_IMAGE_VIEW_TYPE_2D;
             sampleCount = VK_SAMPLE_COUNT_1_BIT;
             syncedTextureParamsVersion = 0;
+            syncedContentVersion = 0;
         }
 
         ~TextureResource() {

MobileGL/MG_State/GLState/TextureState/TextureObject.cpp

@@ -207,6 +207,10 @@ namespace MobileGL {
                 return m_textureParamsVersion;
             }
 
+            Uint64 TextureObjectBase::GetContentVersion() const {
+                return m_contentVersion;
+            }
+
             Int TextureObjectBase::GetSamples() const {
                 return m_samples;
             }
@@ -257,6 +261,9 @@ namespace MobileGL {
 
             void TextureObjectWithOneMipmap::MarkStorageDirty(TextureUploadTarget uploadTarget, Uint mipmapLevel,
                                                               Bool dirty) {
+                if (dirty) {
+                    ++m_contentVersion;
+                }
                 m_textureStorage.MarkDirty(GetIndexOfTextureUploadTarget(uploadTarget), mipmapLevel, dirty);
             }
 

MobileGL/MG_State/GLState/TextureState/TextureObject.h

@@ -47,6 +47,10 @@ namespace MobileGL::MG_State::GLState {
         virtual Uint GetImmutableLevels() const = 0;
         virtual void SetImmutableLevels(Uint levels) = 0;
         virtual Uint16 GetTextureParamsVersion() const = 0;
+        // Monotonic counter bumped on every CPU-side pixel mutation (see MarkStorageDirty).
+        // Backends compare it against a per-resource snapshot to skip re-syncing unchanged
+        // textures across draws (e.g. the block atlas bound across a whole terrain batch).
+        virtual Uint64 GetContentVersion() const = 0;
         virtual Int GetSamples() const = 0;
         virtual void SetSamples(Int samples) = 0;
         virtual Bool HasFixedSampleLocations() const = 0;
@@ -86,6 +90,7 @@ namespace MobileGL::MG_State::GLState {
         Uint GetImmutableLevels() const override;
         void SetImmutableLevels(Uint levels) override;
         Uint16 GetTextureParamsVersion() const override;
+        Uint64 GetContentVersion() const override;
         Int GetSamples() const override;
         void SetSamples(Int samples) override;
         Bool HasFixedSampleLocations() const override;
@@ -108,6 +113,9 @@ namespace MobileGL::MG_State::GLState {
         UintVec2 m_levelRange = {0, 1000};
         Uint m_immutableLevels = 0;
         Uint16 m_textureParamsVersion = 0;
+        // Starts at 1 so a freshly-created backend resource (snapshot 0) never spuriously
+        // matches before its first sync. Bumped only on dirty=true in MarkStorageDirty.
+        Uint64 m_contentVersion = 1;
         Int m_samples = 0;
         Bool m_fixedSampleLocations = true;
     };

MobileGL/MG_State/GLState/TextureState/TextureObject2DCube.cpp

@@ -41,6 +41,9 @@ namespace MobileGL {
             }
 
             void TextureObject2DCube::MarkStorageDirty(TextureUploadTarget uploadTarget, Uint mipmapLevel, bool dirty) {
+                if (dirty) {
+                    ++m_contentVersion;
+                }
                 m_textureStorage.MarkDirty(GetIndexOfTextureUploadTarget(uploadTarget), mipmapLevel, dirty);
             }