[UE4]CustomAnimationBlueprintNode 自定义动画蓝图节点

转自：http://www.cnblogs.com/corgi/p/5405453.html

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

1.Animation Node, Entire Source for a TurnIn Place Node

https://wiki.unrealengine.com/Animation_Node,_Entire_Source_for_a_Turn_In_Place_Node

2. 创建自定义动画节点

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

3.UE引擎中部分节点如AnimNode_CopyBone,AnimNode_ModifyBone的源代码