Files
UnrealEngine/Engine/Plugins/Runtime/StateTree/Source/StateTreeModule/Public/Blueprint/StateTreeTaskBlueprintBase.h
2025-05-18 13:04:45 +08:00

210 lines
9.7 KiB
C++

// Copyright Epic Games, Inc. All Rights Reserved.
#pragma once
#include "Templates/SubclassOf.h"
#include "StateTreeTaskBase.h"
#include "StateTreeNodeBlueprintBase.h"
#include "StateTreeNodeRef.h"
#include "StateTreeTaskBlueprintBase.generated.h"
#define UE_API STATETREEMODULE_API
struct FStateTreeExecutionContext;
DECLARE_DYNAMIC_DELEGATE(FStateTreeDynamicDelegate);
/*
* Base class for Blueprint based Tasks.
*/
UCLASS(MinimalAPI, Abstract, Blueprintable)
class UStateTreeTaskBlueprintBase : public UStateTreeNodeBlueprintBase
{
GENERATED_BODY()
public:
UE_API UStateTreeTaskBlueprintBase(const FObjectInitializer& ObjectInitializer);
/**
* Called when a new state is entered and task is part of active states.
* Use FinishTask() to set the task execution completed. State completion is controlled by completed tasks.
*
* GameplayTasks and other latent actions should be generally triggered on EnterState. When using a GameplayTasks it's required
* to manually cancel active tasks on ExitState if the GameplayTask's lifetime is tied to the State Tree task.
*
* @param Transition Describes the states involved in the transition
*/
UFUNCTION(BlueprintImplementableEvent, meta = (DisplayName = "EnterState"))
UE_API void ReceiveLatentEnterState(const FStateTreeTransitionResult& Transition);
/**
* Called when a current state is exited and task is part of active states.
* @param Transition Describes the states involved in the transition
*/
UFUNCTION(BlueprintImplementableEvent, meta = (DisplayName = "ExitState"))
UE_API void ReceiveExitState(const FStateTreeTransitionResult& Transition);
/**
* Called right after a state has been completed, but before new state has been selected. StateCompleted is called in reverse order to allow to propagate state to other Tasks that
* are executed earlier in the tree. Note that StateCompleted is not called if conditional transition changes the state.
* @param CompletionStatus Describes the running status of the completed state (Succeeded/Failed).
* @param CompletedActiveStates Active states at the time of completion.
*/
UFUNCTION(BlueprintImplementableEvent, meta = (DisplayName = "StateCompleted"))
UE_API void ReceiveStateCompleted(const EStateTreeRunStatus CompletionStatus, const FStateTreeActiveStates CompletedActiveStates);
/**
* Called during state tree tick when the task is on active state.
* Use FinishTask() to set the task execution completed. State completion is controlled by completed tasks.
*
* Triggering GameplayTasks and other latent action should generally be done on EnterState. Tick is called on each update (or event)
* and can cause huge amount of task added if the logic is not handled carefully.
* Tick should be generally be used for monitoring that require polling, or actions that require constant ticking.
*
* Note: The method is called only if bShouldCallTick or bShouldCallTickOnlyOnEvents is set.
* @param DeltaTime Time since last StateTree tick.
*/
UFUNCTION(BlueprintImplementableEvent, meta = (DisplayName = "Tick"))
UE_API void ReceiveLatentTick(const float DeltaTime);
UE_DEPRECATED(all, "Use the new EnterState event without without return value instead. Task status is now controlled via FinishTask node, instead of a return value. Default status is running.")
UFUNCTION(BlueprintImplementableEvent, meta = (DisplayName = "EnterState (Deprecated)", DeprecatedFunction, DeprecationMessage="Use the new EnterState event without without return value instead. Task status is now controlled via FinishTask node, instead of a return value. Default status is running."))
UE_API EStateTreeRunStatus ReceiveEnterState(const FStateTreeTransitionResult& Transition);
UE_DEPRECATED(all, "Use the new Tick event without without return value instead. Task status is now controlled via FinishTask node, instead of a return value. Default status is running.")
UFUNCTION(BlueprintImplementableEvent, meta = (DisplayName = "Tick (Deprecated)", DeprecatedFunction, DeprecationMessage="Use the new Tick event without without return value instead. Task status is now controlled via FinishTask node, instead of a return value. Default status is running."))
UE_API EStateTreeRunStatus ReceiveTick(const float DeltaTime);
protected:
UE_API virtual EStateTreeRunStatus EnterState(FStateTreeExecutionContext& Context, const FStateTreeTransitionResult& Transition);
UE_API virtual void ExitState(FStateTreeExecutionContext& Context, const FStateTreeTransitionResult& Transition);
UE_API virtual void StateCompleted(FStateTreeExecutionContext& Context, const EStateTreeRunStatus CompletionStatus, const FStateTreeActiveStates& CompletedActiveStates);
UE_API virtual EStateTreeRunStatus Tick(FStateTreeExecutionContext& Context, const float DeltaTime);
/** Finish the task and sets it's status. */
UFUNCTION(BlueprintCallable, Category = "StateTree", meta = (HideSelfPin = "true", DisplayName = "Finish Task"))
UE_API void FinishTask(const bool bSucceeded = true);
/** Broadcasts the dispatcher. It will triggers bound callback (bound with BindDelegate) and bound transitions. */
UFUNCTION(BlueprintCallable, Category = "StateTree")
UE_API void BroadcastDelegate(FStateTreeDelegateDispatcher Dispatcher);
/**
* Registers the callback to the listener.
* If the listener was previously registered, then unregister it first before registering it again with the new delegate callback.
* The listener is bound to a dispatcher in the editor.
*/
UFUNCTION(BlueprintCallable, Category = "StateTree")
UE_API void BindDelegate(const FStateTreeDelegateListener& Listener, const FStateTreeDynamicDelegate& Delegate);
/** Unregisters the callback bound to the listener. */
UFUNCTION(BlueprintCallable, Category = "StateTree")
UE_API void UnbindDelegate(const FStateTreeDelegateListener& Listener);
#if WITH_EDITORONLY_DATA
UE_DEPRECATED(5.6, "FStateTreeWeakTaskRef is deprecated.")
/** Cached task while the node is active for async execution. */
PRAGMA_DISABLE_DEPRECATION_WARNINGS
mutable FStateTreeWeakTaskRef WeakTaskRef;
PRAGMA_ENABLE_DEPRECATION_WARNINGS
#endif
/** Run status when using latent EnterState and Tick */
EStateTreeRunStatus RunStatus = EStateTreeRunStatus::Running;
/**
* If set to true, the task will receive EnterState/ExitState even if the state was previously active.
* Generally this should be true for action type tasks, like playing animation,
* and false on state like tasks like claiming a resource that is expected to be acquired on child states. */
UPROPERTY(EditDefaultsOnly, Category="Default")
uint8 bShouldStateChangeOnReselect : 1;
/**
* If set to true, Tick() is called. Not ticking implies no property copy. Default true.
* Note: this is intentionally not a property, should be only set by C++ derived classes when the tick should not be called.
*/
uint8 bShouldCallTick : 1;
/** If set to true, Tick() is called. Default false. */
UPROPERTY(EditDefaultsOnly, Category="Default")
uint8 bShouldCallTickOnlyOnEvents : 1;
/** If set to true, copy the values of bound properties before calling Tick(). Default true. */
UPROPERTY(EditDefaultsOnly, Category="Default")
uint8 bShouldCopyBoundPropertiesOnTick : 1;
/** If set to true, copy the values of bound properties before calling ExitState(). Default true. */
UPROPERTY(EditDefaultsOnly, Category="Default")
uint8 bShouldCopyBoundPropertiesOnExitState : 1;
public:
#if WITH_EDITORONLY_DATA
/**
* True if the task is considered for completion.
* False if the task runs in the background without affecting the state completion.
*/
UPROPERTY(EditDefaultsOnly, Category = "Default")
uint8 bConsideredForCompletion : 1;
/** True if the user can edit bConsideredForCompletion in the editor. */
UPROPERTY(EditDefaultsOnly, Category = "Default")
uint8 bCanEditConsideredForCompletion : 1;
#endif
protected:
uint8 bHasExitState : 1;
uint8 bHasStateCompleted : 1;
uint8 bHasLatentEnterState : 1;
uint8 bHasLatentTick : 1;
UE_DEPRECATED(all, "Use bHasLatentEnterState instead.")
uint8 bHasEnterState_DEPRECATED : 1;
UE_DEPRECATED(all, "Use bHasLatentTick instead.")
uint8 bHasTick_DEPRECATED : 1;
mutable uint8 bIsProcessingEnterStateOrTick : 1;
friend struct FStateTreeBlueprintTaskWrapper;
};
/**
* Wrapper for Blueprint based Tasks.
*/
USTRUCT()
struct FStateTreeBlueprintTaskWrapper : public FStateTreeTaskBase
{
GENERATED_BODY()
virtual const UStruct* GetInstanceDataType() const override
{
return TaskClass;
};
UE_API virtual bool Link(FStateTreeLinker& Linker) override;
UE_API virtual EStateTreeRunStatus EnterState(FStateTreeExecutionContext& Context, const FStateTreeTransitionResult& Transition) const override;
UE_API virtual void ExitState(FStateTreeExecutionContext& Context, const FStateTreeTransitionResult& Transition) const override;
UE_API virtual void StateCompleted(FStateTreeExecutionContext& Context, const EStateTreeRunStatus CompletionStatus, const FStateTreeActiveStates& CompletedActiveStates) const override;
UE_API virtual EStateTreeRunStatus Tick(FStateTreeExecutionContext& Context, const float DeltaTime) const override;
#if WITH_EDITOR
UE_API virtual EDataValidationResult Compile(UE::StateTree::ICompileNodeContext& Context) override;
UE_API virtual FText GetDescription(const FGuid& ID, FStateTreeDataView InstanceDataView, const IStateTreeBindingLookup& BindingLookup, EStateTreeNodeFormatting Formatting = EStateTreeNodeFormatting::Text) const override;
UE_API virtual FName GetIconName() const override;
UE_API virtual FColor GetIconColor() const override;
#endif
UPROPERTY()
TSubclassOf<UStateTreeTaskBlueprintBase> TaskClass = nullptr;
UPROPERTY()
uint8 TaskFlags = 0;
private:
#if WITH_EDITORONLY_DATA
// The node will use the blueprint data instead.
using FStateTreeTaskBase::bConsideredForCompletion;
using FStateTreeTaskBase::bCanEditConsideredForCompletion;
#endif
};
#undef UE_API