C++ TMap::GenerateKeyArray方法代码示例

	/**
	* Nulls out references to a given object
	*
	* @param InObject - Object to null references to
	*/
	void NullReferencesToObject(UObject* InObject)
	{
		TArray<UObject*> ReplaceableObjects;
		TMap<UObject*, UObject*> ReplacementMap;
		ReplacementMap.Add(InObject, NULL);
		ReplacementMap.GenerateKeyArray(ReplaceableObjects);

		// Find all the properties (and their corresponding objects) that refer to any of the objects to be replaced
		TMap< UObject*, TArray<UProperty*> > ReferencingPropertiesMap;
		for (FObjectIterator ObjIter; ObjIter; ++ObjIter)
		{
			UObject* CurObject = *ObjIter;

			// Find the referencers of the objects to be replaced
			FFindReferencersArchive FindRefsArchive(CurObject, ReplaceableObjects);

			// Inform the object referencing any of the objects to be replaced about the properties that are being forcefully
			// changed, and store both the object doing the referencing as well as the properties that were changed in a map (so that
			// we can correctly call PostEditChange later)
			TMap<UObject*, int32> CurNumReferencesMap;
			TMultiMap<UObject*, UProperty*> CurReferencingPropertiesMMap;
			if (FindRefsArchive.GetReferenceCounts(CurNumReferencesMap, CurReferencingPropertiesMMap) > 0)
			{
				TArray<UProperty*> CurReferencedProperties;
				CurReferencingPropertiesMMap.GenerateValueArray(CurReferencedProperties);
				ReferencingPropertiesMap.Add(CurObject, CurReferencedProperties);
				for (TArray<UProperty*>::TConstIterator RefPropIter(CurReferencedProperties); RefPropIter; ++RefPropIter)
				{
					CurObject->PreEditChange(*RefPropIter);
				}
			}

		}

		// Iterate over the map of referencing objects/changed properties, forcefully replacing the references and then
		// alerting the referencing objects the change has completed via PostEditChange
		int32 NumObjsReplaced = 0;
		for (TMap< UObject*, TArray<UProperty*> >::TConstIterator MapIter(ReferencingPropertiesMap); MapIter; ++MapIter)
		{
			++NumObjsReplaced;

			UObject* CurReplaceObj = MapIter.Key();
			const TArray<UProperty*>& RefPropArray = MapIter.Value();

			FArchiveReplaceObjectRef<UObject> ReplaceAr(CurReplaceObj, ReplacementMap, false, true, false);

			for (TArray<UProperty*>::TConstIterator RefPropIter(RefPropArray); RefPropIter; ++RefPropIter)
			{
				FPropertyChangedEvent PropertyEvent(*RefPropIter);
				CurReplaceObj->PostEditChangeProperty(PropertyEvent);
			}

			if (!CurReplaceObj->HasAnyFlags(RF_Transient) && CurReplaceObj->GetOutermost() != GetTransientPackage())
			{
				if (!CurReplaceObj->RootPackageHasAnyFlags(PKG_CompiledIn))
				{
					CurReplaceObj->MarkPackageDirty();
				}
			}
		}
	}

//.........这里部分代码省略.........
				OldObject->RemoveFromRoot();
				OldObject->MarkPendingKill();

				OldToNewInstanceMap.Add(OldObject, NewUObject);

				if (bIsComponent)
				{
					UActorComponent* Component = Cast<UActorComponent>(NewUObject);
					AActor* OwningActor = Component->GetOwner();
					if (OwningActor)
					{
						OwningActor->ResetOwnedComponents();

						// Check to see if they have an editor that potentially needs to be refreshed
						if (OwningActor->GetClass()->ClassGeneratedBy)
						{
							PotentialEditorsForRefreshing.AddUnique(OwningActor->GetClass()->ClassGeneratedBy);
						}

						// we need to keep track of actor instances that need 
						// their construction scripts re-ran (since we've just 
						// replaced a component they own)
						OwnersToReconstruct.Add(OwningActor);
					}
				}
			}

			// If this original object came from a blueprint and it was in the selected debug set, change the debugging to the new object.
			if ((CorrespondingBlueprint) && (OldBlueprintDebugObject) && (NewUObject))
			{
				CorrespondingBlueprint->SetObjectBeingDebugged(NewUObject);
			}

			if (bLogConversions)
			{
				UE_LOG(LogBlueprint, Log, TEXT("Converted instance '%s' to '%s'"), *OldObject->GetPathName(), *NewUObject->GetPathName());
			}
		}
	}

	GEditor->OnObjectsReplaced().Remove(OnObjectsReplacedHandle);

	// Now replace any pointers to the old archetypes/instances with pointers to the new one
	TArray<UObject*> SourceObjects;
	TArray<UObject*> DstObjects;

	OldToNewInstanceMap.GenerateKeyArray(SourceObjects);
	OldToNewInstanceMap.GenerateValueArray(DstObjects); // Also look for references in new spawned objects.

	SourceObjects.Append(DstObjects);

	FReplaceReferenceHelper::IncludeCDO(OldClass, NewClass, OldToNewInstanceMap, SourceObjects, OriginalCDO);
	FReplaceReferenceHelper::FindAndReplaceReferences(SourceObjects, ObjectsThatShouldUseOldStuff, ObjectsToReplace, OldToNewInstanceMap, ReinstancedObjectsWeakReferenceMap);

	{ BP_SCOPED_COMPILER_EVENT_STAT(EKismetReinstancerStats_ReplacementConstruction);

		// the process of setting up new replacement actors is split into two 
		// steps (this here, is the second)...
		// 
		// the "finalization" here runs the replacement actor's construction-
		// script and is left until late to account for a scenario where the 
		// construction-script attempts to modify another instance of the 
		// same class... if this were to happen above, in the ObjectsToReplace 
		// loop, then accessing that other instance would cause an assert in 
		// UProperty::ContainerPtrToValuePtrInternal() (which appropriatly 
		// complains that the other instance's type doesn't match because it 
		// hasn't been replaced yet... that's why we wait until after 
		// FArchiveReplaceObjectRef to run construction-scripts).
		for (FActorReplacementHelper& ReplacementActor : ReplacementActors)
		{
			ReplacementActor.Finalize(ObjectRemappingHelper.ReplacedObjects);
		}
	}

	SelectedActors->EndBatchSelectOperation();
	if (bSelectionChanged)
	{
		GEditor->NoteSelectionChange();
	}

	if (GEditor)
	{
		// Refresh any editors for objects that we've updated components for
		for (auto BlueprintAsset : PotentialEditorsForRefreshing)
		{
			FBlueprintEditor* BlueprintEditor = static_cast<FBlueprintEditor*>(FAssetEditorManager::Get().FindEditorForAsset(BlueprintAsset, /*bFocusIfOpen =*/false));
			if (BlueprintEditor)
			{
				BlueprintEditor->RefreshEditors();
			}
		}
	}

	// in the case where we're replacing component instances, we need to make 
	// sure to re-run their owner's construction scripts
	for (AActor* ActorInstance : OwnersToReconstruct)
	{
		ActorInstance->RerunConstructionScripts();
	}
}

void FStatsMemoryDumpCommand::ProcessMemoryOperations( const TMap<int64, FStatPacketArray>& CombinedHistory )
{
	// This is only example code, no fully implemented, may sometimes crash.
	// This code is not optimized. 
	double PreviousSeconds = FPlatformTime::Seconds();
	uint64 NumMemoryOperations = 0;

	// Generate frames
	TArray<int64> Frames;
	CombinedHistory.GenerateKeyArray( Frames );
	Frames.Sort();

	// Raw stats callstack for this stat packet array.
	TMap<FName, FStackState> StackStates;

	// All allocation ordered by the sequence tag.
	// There is an assumption that the sequence tag will not turn-around.
	//TMap<uint32, FAllocationInfo> SequenceAllocationMap;
	TArray<FAllocationInfo> SequenceAllocationArray;

	// Pass 1.
	// Read all stats messages, parse all memory operations and decode callstacks.
	const int64 FirstFrame = 0;
	PreviousSeconds -= NumSecondsBetweenLogs;
	for( int32 FrameIndex = 0; FrameIndex < Frames.Num(); ++FrameIndex )
	{
        {
            const double CurrentSeconds = FPlatformTime::Seconds();
            if( CurrentSeconds > PreviousSeconds + NumSecondsBetweenLogs )
            {
                UE_LOG( LogStats, Warning, TEXT( "Processing frame %i/%i" ), FrameIndex+1, Frames.Num() );
                PreviousSeconds = CurrentSeconds;
            }
        }

		const int64 TargetFrame = Frames[FrameIndex];
		const int64 Diff = TargetFrame - FirstFrame;
		const FStatPacketArray& Frame = CombinedHistory.FindChecked( TargetFrame );

		bool bAtLeastOnePacket = false;
		for( int32 PacketIndex = 0; PacketIndex < Frame.Packets.Num(); PacketIndex++ )
		{
            {
                const double CurrentSeconds = FPlatformTime::Seconds();
                if( CurrentSeconds > PreviousSeconds + NumSecondsBetweenLogs )
                {
                    UE_LOG( LogStats, Log, TEXT( "Processing packet %i/%i" ), PacketIndex, Frame.Packets.Num() );
                    PreviousSeconds = CurrentSeconds;
                    bAtLeastOnePacket = true;
                }
            }

			const FStatPacket& StatPacket = *Frame.Packets[PacketIndex];
			const FName& ThreadFName = StatsThreadStats.Threads.FindChecked( StatPacket.ThreadId );
			const uint32 NewThreadID = ThreadIDtoStatID.FindChecked( StatPacket.ThreadId );

			FStackState* StackState = StackStates.Find( ThreadFName );
			if( !StackState )
			{
				StackState = &StackStates.Add( ThreadFName );
				StackState->Stack.Add( ThreadFName );
				StackState->Current = ThreadFName;
			}

			const FStatMessagesArray& Data = StatPacket.StatMessages;

			int32 LastPct = 0;
			const int32 NumDataElements = Data.Num();
			const int32 OnerPercent = FMath::Max( NumDataElements / 100, 1024 );
			bool bAtLeastOneMessage = false;
			for( int32 Index = 0; Index < NumDataElements; Index++ )
			{
				if( Index % OnerPercent )
				{
					const double CurrentSeconds = FPlatformTime::Seconds();
					if( CurrentSeconds > PreviousSeconds + NumSecondsBetweenLogs )
					{
						const int32 CurrentPct = int32( 100.0*(Index + 1) / NumDataElements );
						UE_LOG( LogStats, Log, TEXT( "Processing %3i%% (%i/%i) stat messages" ), CurrentPct, Index, NumDataElements );
						PreviousSeconds = CurrentSeconds;
						bAtLeastOneMessage = true;
					}
				}

				const FStatMessage& Item = Data[Index];

				const EStatOperation::Type Op = Item.NameAndInfo.GetField<EStatOperation>();
				const FName RawName = Item.NameAndInfo.GetRawName();

				if( Op == EStatOperation::CycleScopeStart || Op == EStatOperation::CycleScopeEnd || Op == EStatOperation::Memory )
				{
					if( Op == EStatOperation::CycleScopeStart )
					{
						StackState->Stack.Add( RawName );
						StackState->Current = RawName;
					}
					else if( Op == EStatOperation::Memory )
					{
						// Experimental code used only to test the implementation.
						// First memory operation is Alloc or Free
//.........这里部分代码省略.........

//.........这里部分代码省略.........
		int64 MaximumPacketSize = 0;
		int64 TotalPacketsNum = 0;
		// Read all packets sequentially, force by the memory profiler which is now a part of the raw stats.
		// !!CAUTION!! Frame number in the raw stats is pointless, because it is time based, not frame based.
		// Background threads usually execute time consuming operations, so the frame number won't be valid.
		// Needs to be combined by the thread and the time, not by the frame number.
		{
			// Display log information once per 5 seconds to avoid spamming.
			double PreviousSeconds = FPlatformTime::Seconds();
			const int64 FrameOffset0 = Stream.FramesInfo[0].FrameFileOffset;
			FileReader->Seek( FrameOffset0 );

			const int64 FileSize = FileReader->TotalSize();

			while( FileReader->Tell() < FileSize )
			{
				// Read the compressed data.
				FCompressedStatsData UncompressedData( SrcArray, DestArray );
				*FileReader << UncompressedData;
				if( UncompressedData.HasReachedEndOfCompressedData() )
				{
					break;
				}

				FMemoryReader MemoryReader( DestArray, true );

				FStatPacket* StatPacket = new FStatPacket();
				Stream.ReadStatPacket( MemoryReader, *StatPacket );

				const int64 StatPacketFrameNum = StatPacket->Frame;
				FStatPacketArray& Frame = CombinedHistory.FindOrAdd( StatPacketFrameNum );

				// Check if we need to combine packets from the same thread.
				FStatPacket** CombinedPacket = Frame.Packets.FindByPredicate( [&]( FStatPacket* Item ) -> bool
				{
					return Item->ThreadId == StatPacket->ThreadId;
				} );

				const int64 PacketSize = StatPacket->StatMessages.GetAllocatedSize();
				TotalStatMessagesNum += StatPacket->StatMessages.Num();

				if( CombinedPacket )
				{
					TotalDataSize -= (*CombinedPacket)->StatMessages.GetAllocatedSize();
					(*CombinedPacket)->StatMessages += StatPacket->StatMessages;
					TotalDataSize += (*CombinedPacket)->StatMessages.GetAllocatedSize();

					delete StatPacket;
				}
				else
				{
					Frame.Packets.Add( StatPacket );
					TotalDataSize += PacketSize;
				}

				const double CurrentSeconds = FPlatformTime::Seconds();
				if( CurrentSeconds > PreviousSeconds + NumSecondsBetweenLogs )
				{
					const int32 PctPos = int32( 100.0*FileReader->Tell() / FileSize );
					UE_LOG( LogStats, Log, TEXT( "%3i%% %10llu (%.1f MB) read messages, last read frame %4i" ), PctPos, TotalStatMessagesNum, TotalDataSize / 1024.0f / 1024.0f, StatPacketFrameNum );
					PreviousSeconds = CurrentSeconds;
				}
			
				MaximumPacketSize = FMath::Max( MaximumPacketSize, PacketSize );			
				TotalPacketsNum++;
			}
		}

		// Dump frame stats
		for( const auto& It : CombinedHistory )
		{
			const int64 FrameNum = It.Key;
			int64 FramePacketsSize = 0;
			int64 FrameStatMessages = 0;
			int64 FramePackets = It.Value.Packets.Num(); // Threads
			for( const auto& It2 : It.Value.Packets )
			{
				FramePacketsSize += It2->StatMessages.GetAllocatedSize();
				FrameStatMessages += It2->StatMessages.Num();
			}

			UE_LOG( LogStats, Warning, TEXT( "Frame: %10llu/%3lli Size: %.1f MB / %10lli" ), 
					FrameNum, 
					FramePackets, 
					FramePacketsSize / 1024.0f / 1024.0f,
					FrameStatMessages );
		}

		UE_LOG( LogStats, Warning, TEXT( "TotalPacketSize: %.1f MB, Max: %1f MB" ),
				TotalDataSize / 1024.0f / 1024.0f,
				MaximumPacketSize / 1024.0f / 1024.0f );

		TArray<int64> Frames;
		CombinedHistory.GenerateKeyArray( Frames );
		Frames.Sort();
		const int64 MiddleFrame = Frames[Frames.Num() / 2];

		ProcessMemoryOperations( CombinedHistory );
	}
}

//.........这里部分代码省略.........
					return Item->ThreadId == StatPacket->ThreadId;
				});
				
				if( CombinedPacket )
				{
					(*CombinedPacket)->StatMessages += StatPacket->StatMessages;
				}
				else
				{
					Frame.Packets.Add(StatPacket);
				}

				const int64 CurrentPos = FileReader->Tell();
				const int32 PctPos = int32(100.0f*CurrentPos/FileSize);

				UE_LOG( LogStats, Log, TEXT( "%3i Processing FStatPacket: Frame %5i for thread %5i with %6i messages (%.1f MB)" ), 
					PctPos, 
					StatPacket->Frame, 
					StatPacket->ThreadId, 
					StatPacket->StatMessages.Num(), 
					StatPacket->StatMessages.GetAllocatedSize()/1024.0f/1024.0f );

				const int64 PacketSize = StatPacket->StatMessages.GetAllocatedSize();
				TotalPacketSize += PacketSize;
				MaximumPacketSize = FMath::Max( MaximumPacketSize, PacketSize );
			}
		}

		UE_LOG( LogStats, Log, TEXT( "TotalPacketSize: %.1f MB, Max: %1f MB" ), 
			TotalPacketSize/1024.0f/1024.0f, 
			MaximumPacketSize/1024.0f/1024.0f );

		TArray<int64> Frames;
		CombinedHistory.GenerateKeyArray(Frames);
		Frames.Sort();
		const int64 MiddleFrame = Frames[Frames.Num()/2];


		// Remove all frames without the game thread messages.
		for (int32 FrameIndex = 0; FrameIndex < Frames.Num(); ++FrameIndex)
		{
			const int64 TargetFrame = Frames[FrameIndex];
			const FStatPacketArray& Frame = CombinedHistory.FindChecked( TargetFrame );

			const double GameThreadTimeMS = GetMetaData()->ConvertCyclesToMS( GetFastThreadFrameTimeInternal( Frame, EThreadType::Game ) );

			if (GameThreadTimeMS == 0.0f)
			{
				CombinedHistory.Remove( TargetFrame );
				Frames.RemoveAt( FrameIndex );
				FrameIndex--;
			}
		}
		
	
		StatMetaData->SecondsPerCycle = GetSecondsPerCycle( CombinedHistory.FindChecked(MiddleFrame) );
		check( StatMetaData->GetSecondsPerCycle() > 0.0 );

		//const int32 FirstGameThreadFrame = FindFirstFrameWithGameThread( CombinedHistory, Frames );

		// Prepare profiler frame.
		{
			SCOPE_LOG_TIME( TEXT( "Preparing profiler frames" ), nullptr );

			// Prepare profiler frames.
			double ElapsedTimeMS = 0;