目的：在AnimationBlueprint中使用自定义动画控制节点。

主要过程：

1.      引用相关模块。在Client.Build.cs文件中，PublicDependencyModuleNames.AddRange里加入”AnimGraphRuntime”,“AnimGraph”, “BlueprintGraph”，添加引用模块后可在使用时直接包含头文件名称，而不用指定具体路径。

2.      实现AnimNode类，用于处理更新骨骼位置等具体逻辑；

3.      实现AnimGraphNode类，用于在编辑器中显示信息等；

4.      编辑工程后即可在AnimationBlueprint中使用该节点

下面以我的自定义动画节点CopyParentBone为例，该节点作用是更改当前Component内某骨骼的Transform为Parent Component内同名称骨骼的Transform：

一、添加引用模块

Client.Build.cs

PublicDependencyModuleNames.AddRange(new string[]   
        {   
            "Core",   
            "CoreUObject",   
            "Engine",   
            "InputCore",  
            "AIModule",  
            "GameplayTasks",  
            "Landscape",  
            "Foliage",  
            "AnimGraphRuntime",  
            "AnimGraph",  
            "BlueprintGraph"  
        });  

二、AnimNode类

Public/AnimNode_CopyParentBone.h

/* 
 * \file AnimNode_CopyParentBone.h 
 * 
 * \author: Jia Zhipeng 
 * \date: 2016/02/24  
 */  
  
#pragma once  
#include "AnimNode_SkeletalControlBase.h"  
#include "AnimNode_CopyParentBone.generated.h"  
  
USTRUCT()  
struct FAnimNode_CopyParentBone :public FAnimNode_SkeletalControlBase  
//父类可以是FAnimNode_SkeletalControlBase或者FAnimNode_Base  
//FAnimNode_SkeletalControlBase一般用于对骨骼的控制，通过EvaluateBoneTransforms更改骨骼位置。  
//FAnimNode_Base一般用于对整体MeshBase的更改，通过Evaluate或者EvaluateComponentSpace更改Output.Pose更改全身的位置  
//自定义类继承父类后，override部分接口即可，以下是我用到的主要接口  
{  
    GENERATED_USTRUCT_BODY()  
  
    /** Name of bone to control. **/  
    UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = SkeletalControl)  
    FBoneReference BoneToModify;  
      
public:  
    //  Constructor  
    FAnimNode_CopyParentBone();  
  
//  // FAnimNode_Base interface  
//  显示Debug信息  
    virtual void GatherDebugData(FNodeDebugData& DebugData) override;  
//  // End of FAnimNode_Base interface  
  
    // FAnimNode_SkeletalControlBase interface  
//  更改位置的逻辑实现函数  
    virtual void EvaluateBoneTransforms(USkeletalMeshComponent* SkelComp, FCSPose<FCompactPose>& MeshBases, TArray<FBoneTransform>& OutBoneTransforms) override;  
//  判断用到的骨骼是否有效   
virtual bool IsValidToEvaluate(const USkeleton* Skeleton, const FBoneContainer& RequiredBones) override;  
    // End of FAnimNode_SkeletalControlBase interface  
  
private:  
    // FAnimNode_SkeletalControlBase interface  
//  初始化骨骼引用  
    virtual void InitializeBoneReferences(const FBoneContainer& RequiredBones) override;  
    // End of FAnimNode_SkeletalControlBase interface  
};

Private/AnimNode_CopyParentBone.cpp

/* 
 * \file AnimNode_CopyParentBone.cpp 
 * 
 * \author: Jia Zhipeng 
 * \date: 2016/02/24  
 */  
  
#include "Client.h"//自己的Game.h  
#include "AnimNode_CopyParentBone.h"  
  
FAnimNode_CopyParentBone::FAnimNode_CopyParentBone()  
{  
      
}  
  
//控制骨骼运动的逻辑实现。在OutBoneTransforms里Add需要修改的BoneTransform  
void FAnimNode_CopyParentBone::EvaluateBoneTransforms(USkeletalMeshComponent* SkelComp, FCSPose<FCompactPose>& MeshBases, TArray<FBoneTransform>& OutBoneTransforms)  
{  
    check(OutBoneTransforms.Num() == 0);  
    FTransform NewBoneTM = FTransform::Identity;  
    const FBoneContainer BoneContainer = MeshBases.GetPose().GetBoneContainer();  
      
    USceneComponent* ParentComponent = SkelComp->GetAttachParent();  
    if (ParentComponent)  
        NewBoneTM = ParentComponent->GetSocketTransform(BoneToModify.BoneName, RTS_Component);  
    else  
    {  
        UE_LOG(LogAnimation, Warning, TEXT("FAnimNode_CopyParentBone cannot get parent component"));  
    }  
    OutBoneTransforms.Add(FBoneTransform(BoneToModify.GetCompactPoseIndex(BoneContainer), NewBoneTM));  
}  
  
void FAnimNode_CopyParentBone::GatherDebugData(FNodeDebugData& DebugData)  
{  
    FString DebugLine = DebugData.GetNodeName(this);  
  
    DebugLine += "(";  
    AddDebugNodeData(DebugLine);  
    DebugLine += FString::Printf(TEXT(" Target: %s)"), * BoneToModify.BoneName.ToString());  
    DebugData.AddDebugItem(DebugLine);  
  
    ComponentPose.GatherDebugData(DebugData);  
}  
  
bool FAnimNode_CopyParentBone::IsValidToEvaluate(const USkeleton* Skeleton, const FBoneContainer& RequiredBones)  
{  
    return (BoneToModify.IsValid(RequiredBones));  
}  
  
void FAnimNode_CopyParentBone::InitializeBoneReferences(const FBoneContainer& RequiredBones)  
{  
    BoneToModify.Initialize(RequiredBones);  
}  

三、AnimGraphNode

Public/AnimGraphNode_CopyParentBone.h

/* 
 * \file AnimGraphNode_CopyParentBone.h 
 * 
 * \author: Jia Zhipeng 
 * \date: 2016/02/24 
 * \purporse: 自定义动画节点，在Parent Component中获得与当前Component的根骨骼同名的骨骼Transform，然后设置为当前骨骼的Transform 
 */  
#pragma once  
#include "AnimGraphNode_SkeletalControlBase.h"  
#include "AnimNode_CopyParentBone.h"  
#include "AnimGraphNode_CopyParentBone.generated.h"  
  
UCLASS(MinimalAPI)  
class UAnimGraphNode_CopyParentBone : public UAnimGraphNode_SkeletalControlBase  
{  
    GENERATED_UCLASS_BODY()  
  
    UPROPERTY(EditAnywhere, Category=Settings)  
    FAnimNode_CopyParentBone Node;  
  
    // UEdGraphNode interface  
//  鼠标悬浮在Node上的提示文本  
    virtual FText GetTooltipText() const override;  
//  Node的名字文本     
virtual FText GetNodeTitle(ENodeTitleType::Type TitleType) const override;  
    // End of UEdGraphNode interface  
  
protected:  
    // UAnimGraphNode_SkeletalControlBase interface  
//  返回controller的描述  
    virtual FText GetControllerDescription() const override;  
//  返回引用的AnimNode  
    virtual const FAnimNode_SkeletalControlBase* GetNode() const override { return &Node; }  
    // End of UAnimGraphNode_SkeletalControlBase interface  
      
};  

Private/AnimGraphNode_CopyParenBone.cpp

/* 
 * \file AnimNode_CopyParentBone.cpp 
 * 
 * \author: Jia Zhipeng 
 * \date: 2016/02/24  
 */  
  
#include "Client.h"  
#include "AnimGraphNode_CopyParentBone.h"  
  
#define LOCTEXT_NAMESPACE "A3Nodes"  
UAnimGraphNode_CopyParentBone::UAnimGraphNode_CopyParentBone(const FObjectInitializer& ObjectInitializer)  
:Super(ObjectInitializer)  
{  
}  
  
FText UAnimGraphNode_CopyParentBone::GetTooltipText() const  
{  
    return LOCTEXT("AnimGraphNode_CopyParentBone_Tooltip", "Copy parent bone's transform to this component's root. Their names must be same");  
}  
  
FText UAnimGraphNode_CopyParentBone::GetNodeTitle(ENodeTitleType::Type TitleType) const  
{  
    return LOCTEXT("AnimGraphNode_CopyParentBone_Title", "Copy Parent Bone");  
}  
  
FText UAnimGraphNode_CopyParentBone::GetControllerDescription() const  
{  
    return LOCTEXT("CopyParentBone", "Copy Parent Bone");  
}  
  
#undef LOCTEXT_NAMESPACE

参考内容

创建自定义动画节点

https://www.unrealengine.com/zh-CN/blog/creating-custom-animation-nodes