Animation asset UAnimationAsset

type hierarchy structure

• UObjectBase
  • UObjectBaseUtility
    • UObject
      • UAnimationAsset
        • UAnimSequenceBase
          • UAnimCompositeBase
            • Animation Synthesis of UAnimComposite
            • UAnimMontage animation Montage
          • UAnimSequence animation sequence (note root motion)
          • UAnimStreamable
        • UBlendSpaceBase
          • UBlendSpace mixed space
            • UAimOffsetBlendSpace aim offset blend space
          • UBlendSpace1D one dimensional mixed space
            • Uaimoffsetblendspace 1D one dimensional aiming offset hybrid space
        • UPoseAsset

C + + call

UAnimationAsset

• Loaded are derived classes such as animation sequence and animation montage, which can be played directly

  // load
  UAnimationAsset* AnimDead_I;
  AnimDead_I = LoadObject<UAnimationAsset>(nullptr, TEXT("AnimSequence'/Game/Res/PolygonAdventure/Mannequin/Enemy/Animation/FightGroup/Enemy_Dead_I.Enemy_Dead_I'"));
  
  // Load constructor use
  UAnimationAsset* DeadAnim ; 
  static ConstructorHelpers::FObjectFinder<UAnimationAsset> StaticDeadAnim(TEXT("AnimSequence'/Game/Res/PolygonAdventure/Mannequin/Player/Animation/Player_Death.Player_Death'"));
  DeadAnim = StaticDeadAnim.Object;
  
  // Play, you can keep the last frame
  GetMesh()->PlayAnimation(DeadAnim, false);
  
  // Get duration
  AnimDead_I->GetMaxCurrentTime()
  

UAnimSequence

• Can play directly

• The length of time returned can be used for the behavior tree wait time

• The returned transform can be used to Modify bone if necessary

• Do not set cycle playback, you can freeze at the last frame

  // load
  static ConstructorHelpers::FObjectFinder<UAnimSequence> StaticAnimAttackSeq_III(TEXT("AnimSequence'/Game/Res/PolygonAdventure/Mannequin/Enemy/Animation/FightGroup/Enemy_Attack_III.Enemy_Attack_III'"));
  UAnimSequence* AnimAttackSeq_III;
  AnimAttackSeq_III = StaticAnimAttackSeq_III.Object;
  
  // Get duration
  AnimAttackSeq_III->GetPlayLength()
  // Get transform
  AnimAttackSeq_III->GetBoneTransform(OutputTrans, 0.f, CurrentPlayTime, true);
  

UAnimMontage

• Animation fusion can be realized through slot

• If necessary, you need to set it to freeze the last frame

• The length of the corresponding UAnimSequence can be used for the waiting time of the behavior tree

• It can be played after judging each frame; Or play when you want to call, such as characer and UBTTaskNode

  //play
  Montage_Play(AnimHurt);
  
  // Determine whether to play
  Montage_IsPlaying(AnimHurt)
  
  //Stop Montage
  void Montage_Stop(float InBlendOutTime, const UAnimMontage* Montage = NULL);
  Montage_Stop(0); // Stop all montages
  
  // Several methods related to the last frame of freeze frame
  GetMesh()->GlobalAnimRateScale = 0.f;
  GetMesh()->bNoSkeletonUpdate = true;
  GetMesh()->bPauseAnims = true;
  

Animation instance UAnimInstance and animation blueprint UAnimBlueprint

Article address https://www.cnblogs.com/shiroe/p/15634220.html

sketch

• Generally, when creating an animation blueprint, you need to select the Parent Class of UAnimInstance
• Therefore, after creating the UAnimInstance, write various variables and methods inside it, and then realize the communication between C + + and the blueprint through the animation blueprint. For example, variables are used for animation state machines, and events are used for calling animation notifications
• When Montage is first used, it is usually called in character. Later, it is found that it can also be used in UAnimInstance

C + + call

• Load animation blueprint

// Loading and setting
static  ConstructorHelpers::FClassFinder<UAnimInstance> StaticEnemyAnim(TEXT("AnimBlueprint'/Game/Blueprints/Enemy/BPA_Eneymy.BPA_Eneymy_C'"));
// GetMesh()->SetAnimationMode(EAnimationMode::AnimationBlueprint);
GetMesh()->SetAnimClass(StaticEnemyAnim.Class);

// character get * * UAnimInstance** 
SEAnim = Cast<UEnemyAnim>(GetMesh()->GetAnimInstance());

Behavior tree related modules

• UBTService can be used for data update

• UBTDecorator

• UBlackboardData blackboard data can be inherited by Data Asset under Editor

  • reload-able

    virtual void PostLoad() override;
    

  • Add data, several types

    //Waiting time
    	FBlackboardEntry WaitTime;
    	WaitTime.EntryName = FName(TEXT("WaitTime"));
    	UBlackboardKeyType_Float* WaitTimeKeyType = NewObject<UBlackboardKeyType_Float>();
    	WaitTime.KeyType = WaitTimeKeyType;
    	Keys.Add(WaitTime);
    
    	//Enemy attack type
    	FBlackboardEntry AttackType;
    	AttackType.EntryName = FName(TEXT("AttackType"));
    	UBlackboardKeyType_Enum* EnemyAttackTypeKeyType = NewObject<UBlackboardKeyType_Enum>();
    	// Get enumeration type through reflection
    	EnemyAttackTypeKeyType->EnumType = FindObject<UEnum>(ANY_PACKAGE, *FString("EEnemyAttackType"), true);
    	EnemyAttackTypeKeyType->EnumName = FString("EEnemyAttackType");
    	AttackType.KeyType = EnemyAttackTypeKeyType;
    	Keys.Add(AttackType);
    
    	// Player pointer
    	FBlackboardEntry PlayerPawn;
    	PlayerPawn.EntryName = FName(TEXT("PlayerPawn"));
    	UBlackboardKeyType_Object* PlayerPawnKeyType = NewObject<UBlackboardKeyType_Object>();
    	PlayerPawnKeyType->BaseClass = ASLAiPlayerCharacter::StaticClass();
    	PlayerPawn.KeyType = PlayerPawnKeyType;
    	Keys.Add(PlayerPawn);
    
    	//Whether an action is completed
    	FBlackboardEntry ProcessFinish;
    	ProcessFinish.EntryName = FName(TEXT("ProcessFinish"));
    	ProcessFinish.KeyType = NewObject<UBlackboardKeyType_Bool>();
    	Keys.Add(ProcessFinish);
    

• UBTTaskNode

  • Rewritable function

    // Override execution function
    virtual EBTNodeResult::Type ExecuteTask(UBehaviorTreeComponent& OwnerComp, uint8* NodeMemory) override;
    //Override termination function
    virtual EBTNodeResult::Type AbortTask(UBehaviorTreeComponent& OwnerComp, uint8* NodeMemory) override;
    
    // Set the blackboard data to associate
    UPROPERTY(EditAnywhere,Category="Blackboard")
    		struct FBlackboardKeySelector WaitTime;
    UPROPERTY(EditAnywhere,Category="Blackboard")
    		struct FBlackboardKeySelector Destination;
    UPROPERTY(EditAnywhere,Category="Blackboard")
    		struct FBlackboardKeySelector IsActionFinish;
    

  • ExecuteTask

    • You can obtain character and controller through the parameter OwnerComp, and then access related functions or data
    • Can change blackboard data

    SEController = Cast<AEnemyController>(OwnerComp.GetAIOwner());
    SECharacter = Cast<AEnemyCharacter>(SEController->GetPawn());
    
    // Using the navigation system to obtain random points
    UNavigationSystemV1::K2_GetRandomReachablePointInRadius(SEController, WanderOrigin,DesLoc, WanderRadius);
    OwnerComp.GetBlackboardComponent()->SetValueAsVector(Destination.SelectedKeyName, DesLoc);
    
    // Play the animation and return the duration
    float AttackDuration = SECharacter->PlayAttackAction(EEnemyAttackType::EA_Normal);
    OwnerComp.GetBlackboardComponent()->SetValueAsFloat(WaitTime.SelectedKeyName, AttackDuration);
    

  • AbortTask

    • It is generally used for finishing work, such as clearing timer

  • Return value EBTNodeResult

    • According to the return value, let the behavior tree continue to execute the child node or jump out and return to the parent node

    // Return value
    return EBTNodeResult::Failed;
    return EBTNodeResult::Succeeded;
    return EBTNodeResult::Aborted;