Unreal教学（6）——玩家输入和Pawn（Player Input and Pawns）

Pawn这个单词不会翻译，找不到可以形象描述这个单词的汉语，大概的意思就是可以通过很多的Components合成一个含有多种属性状态的物体。

这里主要是如果获取键盘和鼠标的输入，

在Edit  -- Project Setting -- Engine -- Input里面控制,有两种属性，一种是Action Mappings，另外一种是Axis Mapping.

这两种是有区别的，Action主要针对不是连续的，比如跳，射击等,Axis是连续的，比如移动，旋转等。

贴上代码

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"UCLASS()class UNREALLEARN_API AMyPawn : public APawn{GENERATED_BODY()public:// Sets default values for this pawn's propertiesAMyPawn();protected:// Called when the game starts or when spawnedvirtual void BeginPlay() override;public:// Called every framevirtual void Tick(float DeltaTime) override;// Called to bind functionality to inputvirtual void SetupPlayerInputComponent(class UInputComponent* PlayerInputComponent) override;UPROPERTY(EditAnywhere)USceneComponent* OurVisibleComponent;//Input functionsvoid Move_XAxis(float AxisValue);void Move_YAxis(float AxisValue);void StartGrowing();void StopGrowing();//Input variablesFVector CurrentVelocity;bool bGrowing;};

MyPawn.cpp

// Fill out your copyright notice in the Description page of Project Settings.#include "MyPawn.h"#include "Camera/CameraComponent.h"// Sets default valuesAMyPawn::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;// Set this pawn to be controlled by the lowest-numbered playerAutoPossessPlayer = EAutoReceiveInput::Player0;// Create a dummy root component we can attach things to.RootComponent = CreateDefaultSubobject<USceneComponent>(TEXT("RootComponent"));// Create a camera and a visible objectUCameraComponent* OurCamera = CreateDefaultSubobject<UCameraComponent>(TEXT("OurCamera"));OurVisibleComponent = CreateDefaultSubobject<UStaticMeshComponent>(TEXT("OurVisibleComponent"));// Attach our camera and visible object to our root component. Offset and rotate the camera.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 spawnedvoid AMyPawn::BeginPlay(){Super::BeginPlay();}// Called every framevoid AMyPawn::Tick(float DeltaTime){Super::Tick(DeltaTime);// Handle growing and shrinking based on our "Grow" action    {        float CurrentScale = OurVisibleComponent->GetComponentScale().X;        if (bGrowing)        {            // Grow to double size over the course of one second            CurrentScale += DeltaTime;        }        else        {            // Shrink half as fast as we grow            CurrentScale -= (DeltaTime * 0.5f);        }        // Make sure we never drop below our starting size, or increase past double size.        CurrentScale = FMath::Clamp(CurrentScale, 1.0f, 2.0f);        OurVisibleComponent->SetWorldScale3D(FVector(CurrentScale));    }    // Handle movement based on our "MoveX" and "MoveY" axes    {        if (!CurrentVelocity.IsZero())        {            FVector NewLocation = GetActorLocation() + (CurrentVelocity * DeltaTime);            SetActorLocation(NewLocation);        }    }}// Called to bind functionality to inputvoid AMyPawn::SetupPlayerInputComponent(UInputComponent* PlayerInputComponent){Super::SetupPlayerInputComponent(PlayerInputComponent);// Respond when our "Grow" key is pressed or released.    InputComponent->BindAction("Grow", IE_Pressed, this, &AMyPawn::StartGrowing);    InputComponent->BindAction("Grow", IE_Released, this, &AMyPawn::StopGrowing);    // Respond every frame to the values of our two movement axes, "MoveX" and "MoveY".    InputComponent->BindAxis("MoveX", this, &AMyPawn::Move_XAxis);    InputComponent->BindAxis("MoveY", this, &AMyPawn::Move_YAxis);}void AMyPawn::Move_XAxis(float AxisValue){    // Move at 100 units per second forward or backward    CurrentVelocity.X = FMath::Clamp(AxisValue, -1.0f, 1.0f) * 100.0f;}void AMyPawn::Move_YAxis(float AxisValue){    // Move at 100 units per second right or left    CurrentVelocity.Y = FMath::Clamp(AxisValue, -1.0f, 1.0f) * 100.0f;}void AMyPawn::StartGrowing(){    bGrowing = true;}void AMyPawn::StopGrowing(){    bGrowing = false;}