ue4 weapon

UE4版本4.17，不同版本api可能有差异

静态

1 在骨骼上加socket

在socket上右键-添加浏览资源-找到要添加的那个道具（这个只用来看效果，调位置，不会显示到最终效果中），调整socket位置，知道道具位置合适为止

2 在角色bp上，添加一个staticMesh到Mesh节点下

设置父项插槽到刚才创建的socket，选择自己要使用的道具模型

动态(蓝图)

1 创建骨骼socket，步骤同上

2  用蓝图创建跟上面静态一样的结构

注意使用蓝图和c++创建出来的staticMeshComp运行时，在角色蓝图位置是看不到的，原因未知，但武器是正确显示的

动态(代码)

效果跟上面蓝图一样

先设置socket，然后...

MyCharacter.h

// Fill out your copyright notice in the Description page of Project Settings.#pragma once#include "CoreMinimal.h"#include "GameFramework/Pawn.h"#include "Runtime/CoreUObject/Public/UObject/ConstructorHelpers.h"#include "GameFramework/Character.h"#include "TLog.h"#include "Runtime/Engine/Classes/Engine/EngineTypes.h"#include "Runtime/Engine/Classes/Components/InputComponent.h"#include "Runtime/Engine/Classes/Components/StaticMeshComponent.h"#include "Runtime/Engine/Classes/Engine/SkeletalMeshSocket.h"#include "MyCharacter.generated.h"UCLASS()class NDEMO_CHANGEWEAPON_API AMyCharacter : public ACharacter{GENERATED_BODY()public:// Sets default values for this character's propertiesAMyCharacter();protected:virtual void BeginPlay() override;public:virtual void Tick(float DeltaTime) override;virtual void SetupPlayerInputComponent(class UInputComponent* PlayerInputComponent) override;//这里武器加载的是个单独的UStaticMeshCompvoid WeaponAttach1();void WeaponDettach1();//之类武器加载的是个Actor类型的蓝图，这种较好，方便做复合物体一起绑到角色身上void WeaponAttach2();void WeaponDettach2();UStaticMesh* TUStaticMesh;};

MyCharacter.cpp

#include "MyCharacter.h"AMyCharacter::AMyCharacter(){PrimaryActorTick.bCanEverTick = true;static ConstructorHelpers::FObjectFinder<UStaticMesh> SphereVisualAsset(TEXT("StaticMesh'/Game/model/Effects/Meshes/Items/S_Sword_Basic.S_Sword_Basic'"));if (SphereVisualAsset.Succeeded()){TUStaticMesh = SphereVisualAsset.Object;}}void AMyCharacter::BeginPlay(){Super::BeginPlay();}void AMyCharacter::Tick(float DeltaTime){Super::Tick(DeltaTime);}void AMyCharacter::SetupPlayerInputComponent(UInputComponent* PlayerInputComponent){Super::SetupPlayerInputComponent(PlayerInputComponent);//测试默认按钮绑定，不用再手动设置输入InputComponent->BindAction("Custom_Z", IE_Pressed, this, &AMyCharacter::WeaponAttach1);InputComponent->BindAction("Custom_X", IE_Pressed, this, &AMyCharacter::WeaponDettach1);InputComponent->BindAction("Custom_V", IE_Pressed, this, &AMyCharacter::WeaponAttach2);InputComponent->BindAction("Custom_B", IE_Pressed, this, &AMyCharacter::WeaponDettach2);}void AMyCharacter::WeaponAttach1(){UE_LOG(TLog, Warning, TEXT("WeaponAttach1"));UStaticMeshComponent* C = NewObject<UStaticMeshComponent>(this, "TestWeapon");this->AddOwnedComponent(C);C->RegisterComponent();C->SetStaticMesh(TUStaticMesh);C->SetRelativeLocation(FVector(0.0f, 0.0f, 0.0f));C->SetWorldScale3D(FVector(0.8f));C->AttachToComponent(GetMesh(), FAttachmentTransformRules::SnapToTargetNotIncludingScale, TEXT("hand_right_socket"));}void AMyCharacter::WeaponDettach1() {UE_LOG(TLog, Warning, TEXT("WeaponDettach1"));}void AMyCharacter::WeaponAttach2(){TSubclassOf<AActor> WeaponClass = LoadClass<AActor>(NULL, TEXT("Blueprint'/Game/item/TWeapon.TWeapon_C'"));AActor* MeleeWeapon = GetWorld()->SpawnActor<AActor>(WeaponClass, FVector(0,0,0), FRotator(0,0,0));if (MeleeWeapon){//通过名字获得骨骼绑点const USkeletalMeshSocket *socket = GetMesh()->GetSocketByName("hand_right_socket");//绑定武器模型到骨骼挂点上socket->AttachActor(MeleeWeapon, GetMesh());}}void AMyCharacter::WeaponDettach2(){UE_LOG(TLog, Warning, TEXT("WeaponDettach2"));}

Loaction Rule说明

http://www.devqinwei.com/2016/11/03/ue4-%E5%B0%86actor-acttach-to-%E5%8F%A6%E4%B8%80%E4%B8%AAactor%E9%9C%80%E8%A6%81%E6%B3%A8%E6%84%8F%E7%9A%84/

这里要注意Loaction Rule有三种：Keep Relative , Keep World，Snap to Target。
Keep Relative:
将actor在当前场景中的transform移到parent(Socket)中。(当actor在world中处于原始transform时，它最终效果就是在Socket的预览中的效果。
Keep World:
保持actor在当前场景中的transform，对socket设置transform没有意义。但如果socket移动旋转缩放，会跟随相应移动旋转缩放。
Snap to Target:（最常使用）
使用Socket设置的transform，最终效果与actor在当前场景中的transform无关，最终效果等于socket中预览看到的效果。
DetachFromActor要注意，只有Keep Relative和Keep World选项。
如果使用 Snap to Target 进行attach，那么Keep World让Detach之后对保持之前在Socket调整后的最终尺寸到新的场景中（建议使用该方法）；如果使用Keep Relative，则会让尺寸使用物体原始尺寸。

特殊问题记录

新建character蓝图，actor类型weapon蓝图(里面包含一个staticMesh)

直接把weapon蓝图拖到character的节点上，运行，character会自动移动，原因跟物理有关，weapon中staticMesh默认Collider设置的是BlockAllDynamic，这个只要改成不跟character碰撞就不会使character自动飞走

奇怪的是，如果直接向character上加一个staticMesh collider也设置成BlockAllDynamic却是没问题的

这个问题无论是直接拖动节点，或是代码动态绑都存在