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  3. UBehaviorTreeComponent

UBehaviorTreeComponent

API > API/Runtime > API/Runtime/AIModule

   
Name UBehaviorTreeComponent
Type class
Header File /Engine/Source/Runtime/AIModule/Classes/BehaviorTree/BehaviorTreeComponent.h
Include Path #include "BehaviorTree/BehaviorTreeComponent.h"

Syntax

UCLASS (ClassGroup=AI, Meta=(BlueprintSpawnableComponent), MinimalAPI)  
class UBehaviorTreeComponent : public UBrainComponent

Inheritance Hierarchy

Implements Interfaces

Constructors

Name Remarks Include Path Unreal Specifiers

UBehaviorTreeComponent ( const FObjectInitializer& ObjectInitializer
)

   BehaviorTree/BehaviorTreeComponent.h  
DO NOT USE. This constructor is for internal usage only for hot-reload purposes. BehaviorTree/BehaviorTreeComponent.h  

Structs

Name Remarks
FBranchActionInfo  
FBTSuspendBranchActionsScoped  

Typedefs

Name Type Remarks Include Path
FBTSuspendBranchDeactivationScoped FBTSuspendBranchActionsScoped   BehaviorTree/BehaviorTreeComponent.h

Constants

Name Type Remarks Include Path
ActiveDebuggerCounter int32 Set when at least one debugger window is opened BehaviorTree/BehaviorTreeComponent.h
bAddedEndFrameCallback bool Code for timing BT Search for FramePro. BehaviorTree/BehaviorTreeComponent.h
FrameSearchTime double   BehaviorTree/BehaviorTreeComponent.h
NumSearchTimeCalls int32   BehaviorTree/BehaviorTreeComponent.h

Functions

Public

Name Remarks Include Path Unreal Specifiers

void AddCooldownTagDuration ( FGameplayTag CooldownTag,
float CooldownDuration,
bool bAddToExistingDuration
)

 Add to the cooldown tag's duration BehaviorTree/BehaviorTreeComponent.h
  • BlueprintCallable
  • Category="AI|Logic"

virtual FString DescribeActiveTasks()

   BehaviorTree/BehaviorTreeComponent.h  

virtual FString DescribeActiveTrees()

   BehaviorTree/BehaviorTreeComponent.h  

int32 FindInstanceContainingNode ( const UBTNode* Node
) const

 Tries to find behavior tree instance in context BehaviorTree/BehaviorTreeComponent.h  

UBTNode * FindTemplateNode ( const UBTNode* Node
) const

 Tries to find template node for given instanced node BehaviorTree/BehaviorTreeComponent.h  

void ForEachChildTask ( TFunctionRef< void(UBTTaskNode&, const FBehaviorTreeInstance&, int32 InstanceIndex)> Functor
)

 Will call the given functor on each task node in the current instance stacks. BehaviorTree/BehaviorTreeComponent.h  

void ForEachChildTask ( UBTCompositeNode& StartNode,
int32 InstanceIndex,
TFunctionRef< void(UBTTaskNode&, const FBehaviorTreeInstance&, int32 InstanceIndex)> Functor
)

 Will call the given functor on each child node from the given start node. BehaviorTree/BehaviorTreeComponent.h  

float GetAccumulatedTickDeltaTime()

 Returns the accumulated delta time for the current tick BehaviorTree/BehaviorTreeComponent.h  

uint16 GetActiveInstanceIdx()

 Get index of active instance on stack BehaviorTree/BehaviorTreeComponent.h  

const UBTNode * GetActiveNode()

   BehaviorTree/BehaviorTreeComponent.h  

UBehaviorTree * GetCurrentTree()

   BehaviorTree/BehaviorTreeComponent.h  

uint8 * GetNodeMemory ( const UBTNode* Node,
int32 InstanceIdx
) const

   BehaviorTree/BehaviorTreeComponent.h  

UBehaviorTree * GetRootTree()

   BehaviorTree/BehaviorTreeComponent.h  

double GetTagCooldownEndTime ( FGameplayTag CooldownTag
) const

   BehaviorTree/BehaviorTreeComponent.h
  • BlueprintCallable
  • Category="AI|Logic"

EBTTaskStatus::Type GetTaskStatus ( const UBTTaskNode* TaskNode
) const

   BehaviorTree/BehaviorTreeComponent.h  

bool IsAbortPending()

   BehaviorTree/BehaviorTreeComponent.h  

bool IsAuxNodeActive ( const UBTAuxiliaryNode* AuxNode
) const

   BehaviorTree/BehaviorTreeComponent.h  

bool IsAuxNodeActive ( const UBTAuxiliaryNode* AuxNodeTemplate,
int32 InstanceIdx
) const

   BehaviorTree/BehaviorTreeComponent.h  

bool IsExecutingBranch ( const UBTNode* Node,
int32 ChildIndex
) const

   BehaviorTree/BehaviorTreeComponent.h  

bool IsInstanceStackEmpty()

 Returns true if InstanceStack contains any BT runtime instances BehaviorTree/BehaviorTreeComponent.h  

bool IsRestartPending()

   BehaviorTree/BehaviorTreeComponent.h  

void OnTaskFinished ( const UBTTaskNode* TaskNode,
EBTNodeResult::Type TaskResult
)

 Finish latent execution or abort BehaviorTree/BehaviorTreeComponent.h  

void ProcessExecutionRequest()

 Process execution flow BehaviorTree/BehaviorTreeComponent.h  

void RegisterMessageObserver ( const UBTTaskNode* TaskNode,
FName MessageType,
FAIRequestID MessageID
)

   BehaviorTree/BehaviorTreeComponent.h  

void RegisterMessageObserver ( const UBTTaskNode* TaskNode,
FName MessageType
)

 Setup message observer for given task BehaviorTree/BehaviorTreeComponent.h  

void RegisterParallelTask ( const UBTTaskNode* TaskNode
)

 Add active parallel task BehaviorTree/BehaviorTreeComponent.h  

void RequestBranchActivation ( const UBTDecorator& RequestedBy,
const bool bRequestEvenIfExecuting
)

 Request branch activation: helper for decorator BehaviorTree/BehaviorTreeComponent.h  

void RequestBranchDeactivation ( const UBTDecorator& RequestedBy
)

 Request branch deactivation: helper for decorator BehaviorTree/BehaviorTreeComponent.h  

void RequestBranchEvaluation ( const UBTDecorator& RequestedBy
)

 Request branch evaluation: helper for decorator BehaviorTree/BehaviorTreeComponent.h  

void RequestBranchEvaluation ( EBTNodeResult::Type ContinueWithResult
)

 Request branch evaluation: helper for active node (ex: tasks) BehaviorTree/BehaviorTreeComponent.h  

void RequestExecution ( const UBTCompositeNode* RequestedOn,
const int32 InstanceIdx,
const UBTNode* RequestedBy,
const int32 RequestedByChildIndex,
const EBTNodeResult::Type ContinueWithResult,
bool bStoreForDebugger
)

 Request execution change BehaviorTree/BehaviorTreeComponent.h  

void RequestExecution ( EBTNodeResult::Type ContinueWithResult
)

 Replaced by RequestBranchEvaluation with EBTNodeResult BehaviorTree/BehaviorTreeComponent.h  

void RequestExecution ( const UBTDecorator* RequestedBy
)

 Replaced by the RequestBranchEvaluation from decorator BehaviorTree/BehaviorTreeComponent.h  

void RequestUnregisterAuxNodesInBranch ( const UBTCompositeNode* Node
)

 Request unregistration of aux nodes in the specified branch BehaviorTree/BehaviorTreeComponent.h  

void RestartTree ( EBTRestartMode RestartMode
)

 Restarts execution from root BehaviorTree/BehaviorTreeComponent.h  

void ScheduleExecutionUpdate()

 Schedule execution flow update in next tick BehaviorTree/BehaviorTreeComponent.h  

void ScheduleNextTick ( float NextDeltaTime
)

 END UActorComponent overrides Schedule when will be the next tick, 0.0f means next frame, FLT_MAX means never BehaviorTree/BehaviorTreeComponent.h  

virtual void SetDynamicSubtree ( FGameplayTag InjectTag,
UBehaviorTree* BehaviorAsset,
UBTCompositeNode* OptionalStartingNode
)

 Assign subtree to RunBehaviorDynamic task specified by tag. BehaviorTree/BehaviorTreeComponent.h  

virtual void SetDynamicSubtree ( FGameplayTag InjectTag,
UBehaviorTree* BehaviorAsset
)

 Assign subtree to RunBehaviorDynamic task specified by tag. BehaviorTree/BehaviorTreeComponent.h
  • BlueprintCallable
  • Category="AI|Logic"

void StartTree ( UBehaviorTree& Asset,
EBTExecutionMode::Type ExecuteMode
)

 Starts execution from root BehaviorTree/BehaviorTreeComponent.h  

void StopTree ( EBTStopMode::Type StopMode
)

 Stops execution BehaviorTree/BehaviorTreeComponent.h  

bool TreeHasBeenStarted()

 Indicates instance has been initialized to work with specific BT asset BehaviorTree/BehaviorTreeComponent.h  

void UnregisterAuxNodesInBranch ( const UBTCompositeNode* Node,
bool bApplyImmediately
)

 Unregister all aux nodes in branch of tree BehaviorTree/BehaviorTreeComponent.h  

void UnregisterAuxNodesInRange ( const FBTNodeIndex& FromIndex,
const FBTNodeIndex& ToIndex
)

 Unregister all aux nodes between given execution index range: FromIndex < AuxIndex < ToIndex BehaviorTree/BehaviorTreeComponent.h  

void UnregisterAuxNodesUpTo ( const FBTNodeIndex& Index
)

 Unregister all aux nodes less important than given index BehaviorTree/BehaviorTreeComponent.h  
  BehaviorTree/BehaviorTreeComponent.h  

void UnregisterMessageObserversFrom ( const UBTTaskNode* TaskNode
)

 Remove message observers registered with task BehaviorTree/BehaviorTreeComponent.h  

void UnregisterParallelTask ( const UBTTaskNode* TaskNode,
uint16 InstanceIdx
)

 Remove parallel task BehaviorTree/BehaviorTreeComponent.h  

Overridden from UBrainComponent

Name Remarks Include Path Unreal Specifiers

virtual void Cleanup()

 AI logic won't be needed anymore, stop all activity and run cleanup BehaviorTree/BehaviorTreeComponent.h  

virtual void DescribeSelfToVisLog ( FVisualLogEntry* Snapshot
) const

   BehaviorTree/BehaviorTreeComponent.h  

virtual FString GetDebugInfoString()

   BehaviorTree/BehaviorTreeComponent.h  

virtual void HandleMessage ( const FAIMessage& Message
)

   BehaviorTree/BehaviorTreeComponent.h  

virtual bool IsPaused()

   BehaviorTree/BehaviorTreeComponent.h  

virtual bool IsRunning()

   BehaviorTree/BehaviorTreeComponent.h  

virtual void PauseLogic ( const FString& Reason
)

 Pause logic and blackboard updates. BehaviorTree/BehaviorTreeComponent.h  

virtual void RestartLogic()

 Restarts currently running or previously ran brain logic. BehaviorTree/BehaviorTreeComponent.h  

virtual EAILogicResuming::Type ResumeLogic ( const FString& Reason
)

 Resumes paused brain logic. MUST be called by child implementations! BehaviorTree/BehaviorTreeComponent.h  

virtual void StartLogic()

 Starts brain logic. If brain is already running, will not do anything. BehaviorTree/BehaviorTreeComponent.h  

virtual void StopLogic ( const FString& Reason
)

 Stops currently running brain logic. BehaviorTree/BehaviorTreeComponent.h  

Overridden from UActorComponent

Name Remarks Include Path Unreal Specifiers

virtual void RegisterComponentTickFunctions ( bool bRegister
)

   BehaviorTree/BehaviorTreeComponent.h  

virtual void SetComponentTickEnabled ( bool bEnabled
)

   BehaviorTree/BehaviorTreeComponent.h  

virtual void TickComponent ( float DeltaTime,
enum ELevelTick TickType,
FActorComponentTickFunction* ThisTickFunction
)

 BEGIN UActorComponent overrides BehaviorTree/BehaviorTreeComponent.h  

virtual void UninitializeComponent()

   BehaviorTree/BehaviorTreeComponent.h  

Protected

Name Remarks Include Path Unreal Specifiers

void AbortCurrentTask()

 Abort currently executed task BehaviorTree/BehaviorTreeComponent.h  

void ActivateBranch ( const UBTDecorator& RequestedBy,
bool bRequestEvenIfNotExecuting
)

 Activate a branch as the decorator conditions are now passing BehaviorTree/BehaviorTreeComponent.h  

void ApplyAllSearchUpdates ( const TArray< FBehaviorTreeSearchUpdate >& UpdateList,
int32 NewNodeExecutionIndex,
bool bDoPostUpdate,
bool bAllowTaskUpdates
)

 Apply updates and post update from specified UpdateList. BehaviorTree/BehaviorTreeComponent.h  

void ApplyDiscardedSearch()

 Apply pending node updates required for discarded search BehaviorTree/BehaviorTreeComponent.h  

void ApplySearchData ( UBTNode* NewActiveNode
)

 Apply pending node updates from SearchData BehaviorTree/BehaviorTreeComponent.h  

void ApplySearchUpdates ( const TArray< FBehaviorTreeSearchUpdate >& UpdateList,
int32 NewNodeExecutionIndex,
bool bPostUpdate
)

 Apply updates from specific list BehaviorTree/BehaviorTreeComponent.h  

EBTNodeRelativePriority CalculateRelativePriority ( const UBTNode* NodeA,
const UBTNode* NodeB
) const

 Return NodeA's relative priority in regards to NodeB BehaviorTree/BehaviorTreeComponent.h  

void CopyInstanceMemoryFromPersistent()

 Copy memory block from persistent memory to running instances (rollback) BehaviorTree/BehaviorTreeComponent.h  

void CopyInstanceMemoryToPersistent()

 Copy memory block from running instances to persistent memory BehaviorTree/BehaviorTreeComponent.h  

void DeactivateBranch ( const UBTDecorator& RequestedBy
)

 Deactivate a branch as the decorator conditions are not passing anymore BehaviorTree/BehaviorTreeComponent.h  

bool DeactivateUpTo ( const UBTCompositeNode* Node,
uint16 NodeInstanceIdx,
EBTNodeResult::Type& NodeResult,
int32& OutLastDeactivatedChildIndex
)

 Deactivate all nodes up to requested one BehaviorTree/BehaviorTreeComponent.h  

void EvaluateBranch ( const UBTDecorator& RequestedBy
)

 Evaluate a branch as the decorator conditions have changed BehaviorTree/BehaviorTreeComponent.h  

void EvaluateBranch ( EBTNodeResult::Type LastResult
)

 Evaluate a branch as current active node is finished BehaviorTree/BehaviorTreeComponent.h  

void ExecuteTask ( UBTTaskNode* TaskNode
)

 Execute new task BehaviorTree/BehaviorTreeComponent.h  

bool HasActiveLatentAborts()

 Return true if the current or any parallel task has a latent abort in progress BehaviorTree/BehaviorTreeComponent.h  

virtual void OnTreeFinished()

 Called when tree runs out of nodes to execute BehaviorTree/BehaviorTreeComponent.h  

void ProcessPendingExecution()

 Apply pending execution from last task search BehaviorTree/BehaviorTreeComponent.h  

void ProcessPendingInitialize()

 Apply pending tree initialization BehaviorTree/BehaviorTreeComponent.h  

bool PushInstance ( UBehaviorTree& TreeAsset
)

 Push behavior tree instance on execution stack @NOTE: should never be called out-side of BT execution, meaning only BT tasks can push another BT instance! BehaviorTree/BehaviorTreeComponent.h  

void RemoveAllInstances()

 Remove instanced nodes, known subtree instances and safely clears their persistent memory BehaviorTree/BehaviorTreeComponent.h  

void ResumeBranchActions()

 Resume branch actions and execute all the queued up ones BehaviorTree/BehaviorTreeComponent.h  

void ResumeBranchDeactivation()

   BehaviorTree/BehaviorTreeComponent.h  

void RollbackSearchChanges()

 Restore state of tree to state before search BehaviorTree/BehaviorTreeComponent.h  

void StoreDebuggerBlackboard ( TMap< FName, FString >& BlackboardValueDesc
) const

 Describe blackboard's key values BehaviorTree/BehaviorTreeComponent.h  

void StoreDebuggerExecutionStep ( EBTExecutionSnap::Type SnapType
)

 Make a snapshot for debugger BehaviorTree/BehaviorTreeComponent.h  

void StoreDebuggerInstance ( FBehaviorTreeDebuggerInstance& InstanceInfo,
uint16 InstanceIdx,
EBTExecutionSnap::Type SnapType
) const

 Make a snapshot for debugger from given subtree instance BehaviorTree/BehaviorTreeComponent.h  

void StoreDebuggerRemovedInstance ( uint16 InstanceIdx
) const

   BehaviorTree/BehaviorTreeComponent.h  

void StoreDebuggerRestart ( const UBTNode* Node,
uint16 InstanceIdx,
bool bAllowed
)

 Store restarting node for debugger BehaviorTree/BehaviorTreeComponent.h  

void StoreDebuggerRuntimeValues ( TArray< FString >& RuntimeDescriptions,
UBTNode* RootNode,
uint16 InstanceIdx
) const

 Gather nodes runtime descriptions BehaviorTree/BehaviorTreeComponent.h  

void StoreDebuggerSearchStep ( const UBTNode* Node,
uint16 InstanceIdx,
EBTNodeResult::Type NodeResult
) const

 Store search step for debugger BehaviorTree/BehaviorTreeComponent.h  

void StoreDebuggerSearchStep ( const UBTNode* Node,
uint16 InstanceIdx,
bool bPassed
) const

   BehaviorTree/BehaviorTreeComponent.h  

void SuspendBranchActions ( EBTBranchAction BranchActions
)

 Suspend any branch actions and queue them to be processed later by ResumeBranchActions() BehaviorTree/BehaviorTreeComponent.h  

void SuspendBranchDeactivation()

   BehaviorTree/BehaviorTreeComponent.h  

void TickNewlyAddedAuxNodesHelper()

   BehaviorTree/BehaviorTreeComponent.h  

void TrackNewLatentAborts()

 Tracks if there are new tasks using latent abort in progress BehaviorTree/BehaviorTreeComponent.h  

bool TrackPendingLatentAborts()

 Returns true if execution was waiting on latent aborts and they are all finished; BehaviorTree/BehaviorTreeComponent.h  

void UpdateDebuggerAfterExecution ( const UBTTaskNode* TaskNode,
uint16 InstanceIdx
) const

 Update runtime description of given task node in latest debugger's snapshot BehaviorTree/BehaviorTreeComponent.h  

uint8 UpdateInstanceId ( UBehaviorTree* TreeAsset,
const UBTNode* OriginNode,
int32 OriginInstanceIdx
)

 Add unique Id of newly created subtree to KnownInstances list and return its index BehaviorTree/BehaviorTreeComponent.h  

Static

Name Remarks Include Path Unreal Specifiers

static void EndFrame()

 Code for timing BT Search for FramePro. BehaviorTree/BehaviorTreeComponent.h  

static bool IsDebuggerActive()

 Check if debugger is currently running and can gather data BehaviorTree/BehaviorTreeComponent.h  

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