FVisualizerDebuggingState | Unreal Engine 5.7 Documentation

Global visualizer state manager that handles the complexities of natvis lookup rules for DLLs and LiveCoding

The singleton instance of this class is forward declared in CoreGlobals.h (GCoreDebuggingState), with additional symbols added to each DLL through UE_VISUALIZERS_HELPERS (GDebuggingState).

When a plugin or engine system needs to provide a globally accessible pointer to a natvis visualizer, that pointer can be added by calling FVisualizerDebuggingState::Assign using a globally unique ID that is used to find the pointer in the natvis. GUIDs may be generated using any readily-available GUID generator tool.

Pointers are located using an intrinsic call to strstr that finds the pointer's offset using a string match of the original GUID's lower-case, 32-character string representation of the form "c198d347ec1243ec833c423bd5fb6084". The offset of the address of the match divided by 32 gives the entry index from which the actual debug ptr can be retrieved.

An example visualizer syntax is included below. It is recommended that most natvis files utilizing this method would include an global intrinsic function at the top for quick access:

// C++: struct FMyGlobalState { static FMyGlobalState* GetSingleton(); TArray TypeNames; }; struct FMyStruct { int32 TypeNameIndex; };

// Register the global state FGuid DebugVisualizerID(0x1bdc1747, 0x6b924697, 0xbd8fccc8, 0xb26b4f79) EVisualizerDebuggingStateResult Result = FVisualizerDebuggingState::Assign(DebugVisualizerID, FMyGlobalState::GetSingleton());

// .natvis:

Type={ GetGlobalState()->TypeNames[TypeNameIndex] }


Name	FVisualizerDebuggingState
Type	struct
Header File	/Engine/Source/Runtime/Core/Public/Modules/VisualizerDebuggingState.h
Include Path	#include "Modules/VisualizerDebuggingState.h"

Syntax

struct FVisualizerDebuggingState

Constructors

Name	Remarks	Include Path	Unreal Specifiers
FVisualizerDebuggingState ()		Modules/VisualizerDebuggingState.h
FVisualizerDebuggingState ( const FVisualizerDebuggingState& )		Modules/VisualizerDebuggingState.h
FVisualizerDebuggingState ( FVisualizerDebuggingState&& )		Modules/VisualizerDebuggingState.h

Destructors

Name	Remarks	Include Path	Unreal Specifiers
~FVisualizerDebuggingState()		Modules/VisualizerDebuggingState.h

Functions

Public

Protected

Name	Remarks	Include Path	Unreal Specifiers
EVisualizerDebuggingStateResult AssignImpl ( const FGuid& UniqueId, void* DebugPtr )	Implementation function for Assign	Modules/VisualizerDebuggingState.h
void * Find ( const FGuid& UniqueId ) const	Attempt to locate the index of the specified unique ID	Modules/VisualizerDebuggingState.h

Static

Name	Remarks	Include Path	Unreal Specifiers
static EVisualizerDebuggingStateResult Assign ( const FGuid& UniqueId, void* DebugPtr )	Assign a globally accessible debugging state ptr by name, potentially overwriting a previously assigned ptr	Modules/VisualizerDebuggingState.h

Operators

Name	Remarks	Include Path	Unreal Specifiers
void operator= ( const FVisualizerDebuggingState& )		Modules/VisualizerDebuggingState.h
void operator= ( FVisualizerDebuggingState&& )		Modules/VisualizerDebuggingState.h

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