pawn控制行走和幾何體放縮

官方例子上有錯誤，

那個攝像機應該是成員變量，才能在編輯器中顯示出來，

總動員上的api比較老了，不適合，它們用的attachTo(根組件)，現在已經改爲SetupAttachment（根組件）了

即

_ourCamera->SetupAttachment(RootComponent);

_ourVisibleComponent->SetupAttachment(RootComponent);

 

其他的沒什麼好說的，輸入應該用pawn類，而不是actor，

    virtual void SetupPlayerInputComponent(class UInputComponent* PlayerInputComponent) override;起作用

先上圖，可以看到actor和camera和RootComponent的層級關係

設置輸入關係是在編輯->項目設置->輸入中，操作映射是一步一動，軸映射是連續動

 

上代碼

mypawn.h

// Fill out your copyright notice in the Description page of Project Settings.

#pragma once

#include "CoreMinimal.h"
#include "GameFramework/Pawn.h"
#include "MyPawn.generated.h"

class UCameraComponent;

UCLASS()
class MYSPAWN_DOC_API AMyPawn : public APawn
{
    GENERATED_BODY()

public:
    // Sets default values for this pawn's properties
    AMyPawn();

protected:
    // Called when the game starts or when spawned
    virtual void BeginPlay() override;

public:    
    // Called every frame
    virtual void Tick(float DeltaTime) override;

    // Called to bind functionality to input
    virtual void SetupPlayerInputComponent(class UInputComponent* PlayerInputComponent) override;

public:

    UPROPERTY(EditAnywhere)
    USceneComponent* _ourVisibleComponent;
    UPROPERTY(EditAnywhere)
    UCameraComponent* _ourCamera;

public:
    //輸入函數
    void move_XAxis(float axisValue);
    void move_YAxis(float axisValue);
    void startGrowing();
    void stopGrowing();

public:
    FVector _currentVelocity;
    bool _bGrowing;

};

mypawn.cpp

// Fill out your copyright notice in the Description page of Project Settings.

#include "MyPawn.h"
#include "camera/cameraComponent.h"
#include "components/inputComponent.h"

// Sets default values
AMyPawn::AMyPawn()
{
     // Set this pawn to call Tick() every frame.  You can turn this off to improve performance if you don't need it.
    PrimaryActorTick.bCanEverTick = true;
    //將該pawn設爲由最小編號玩家控制
    AutoPossessPlayer = EAutoReceiveInput::Player0;

    //創建可附加內容的虛擬根組件
    RootComponent = CreateDefaultSubobject<USceneComponent>(TEXT("RootComponent"));
    //創建相機和可見對象
    _ourCamera = CreateDefaultSubobject<UCameraComponent>(TEXT("ourCamera"));
    _ourVisibleComponent = CreateDefaultSubobject<UStaticMeshComponent>(TEXT("ourVisibleComponent"));

    //將相機和可見對象附加到根組件，偏移並旋轉相機
    _ourCamera->SetupAttachment(RootComponent);
    _ourCamera->SetRelativeLocation(FVector(-250.0f, 0.0f, 250.0f));
    _ourCamera->SetRelativeRotation(FRotator(-45.0f, 0.0f, 0.0f));
    _ourVisibleComponent->SetupAttachment(RootComponent);

}

// Called when the game starts or when spawned
void AMyPawn::BeginPlay()
{
    Super::BeginPlay();
    
}

// Called every frame
void AMyPawn::Tick(float DeltaTime)
{
    Super::Tick(DeltaTime);

    //縮放大小
    float currentScale = _ourVisibleComponent->GetComponentScale().X;
    if (_bGrowing)
    {
        currentScale += DeltaTime;
    }
    else
    {
        currentScale -= DeltaTime;
    }

    //確認不低於其實大小，或者增大之前的兩倍大小
    currentScale = FMath::Clamp(currentScale, 1.0f, 2.0f);
    _ourVisibleComponent->SetWorldScale3D(FVector(currentScale));

    //位置
    FVector newLocation = GetActorLocation() + _currentVelocity * DeltaTime;
    SetActorLocation(newLocation);

}

// Called to bind functionality to input
void AMyPawn::SetupPlayerInputComponent(UInputComponent* PlayerInputComponent)
{
    Super::SetupPlayerInputComponent(PlayerInputComponent);

    //按下或鬆開grow
    PlayerInputComponent->BindAction("Grow", IE_Pressed, this, &AMyPawn::startGrowing);
    PlayerInputComponent->BindAction("Grow", IE_Released, this, &AMyPawn::stopGrowing);

    //每幀響應MoveX, MoveY
    PlayerInputComponent->BindAxis("MoveX", this, &AMyPawn::move_XAxis);
    PlayerInputComponent->BindAxis("MoveY", this, &AMyPawn::move_YAxis);

}

void AMyPawn::move_XAxis(float axisValue)
{
    //以每秒100單位的速度前後移動
    _currentVelocity.X = FMath::Clamp(axisValue, -1.0f, 1.0f) * 100.0f;
}

void AMyPawn::move_YAxis(float axisValue)
{
    _currentVelocity.Y = FMath::Clamp(axisValue, -1.0f, 1.0f) * 100.0f;
}

void AMyPawn::startGrowing()
{
    _bGrowing = true;
}

void AMyPawn::stopGrowing()
{
    _bGrowing = false;
}