UE C++ 多镜头设置缩放 平移

一.整体思路

首先需要在 想要控制的躯体Pawn上，生成不同相机对应的SpringArm组件。其次是在Controller上，拿到这个Pawn，并在其中设置输入响应，并定义响应事件。响应事件里有指向Pawn的指针，并把Pawn的缩放平移功能进行调用。

二.

1.CameraPawn的组件构成

	UPROPERTY(VisibleAnywhere, BlueprintReadOnly, Category = MySceneComponent)USceneComponent* MyRoot;UPROPERTY(VisibleAnywhere, BlueprintReadOnly, Category = MySceneComponent)USpringArmComponent* MySpringArm;UPROPERTY(VisibleAnywhere, BlueprintReadOnly, Category = MySceneComponent)UCameraComponent* MyCamera;void Zoom(bool Direction, float ZoomSpeed);void Panx(float x);void Pany(float y);void Back();

ACameraPawn::ACameraPawn()
{// 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;MyRoot = CreateDefaultSubobject<USceneComponent>(TEXT("MyRootComponent"));MySpringArm = CreateDefaultSubobject <USpringArmComponent>(TEXT("MySpringArmComponent"));MyCamera = CreateDefaultSubobject<UCameraComponent>(TEXT("MySCameraComponent"));RootComponent = MyRoot;MySpringArm->SetupAttachment(MyRoot);MyCamera->SetupAttachment(MySpringArm);MySpringArm->bDoCollisionTest = false;
}

2.将Pawn自己镜头伸缩，平移功能，复原写好

void ACameraPawn::Zoom(bool Direction, float ZoomSpeed) {if (Direction) {if (MySpringArm->TargetArmLength >= 300 && MySpringArm->TargetArmLength < 5000) {MySpringArm->TargetArmLength += (ZoomSpeed * 2);GEngine->AddOnScreenDebugMessage(-1, 5.f, FColor::Red, FString::Printf(TEXT("SpringArmLength is %f"), MySpringArm->TargetArmLength));}}else {if (MySpringArm->TargetArmLength > 300 && MySpringArm->TargetArmLength <= 5000) {MySpringArm->TargetArmLength -= (ZoomSpeed * 2);GEngine->AddOnScreenDebugMessage(-1, 5.f, FColor::Red, FString::Printf(TEXT("SpringArmLength is %f"), MySpringArm->TargetArmLength));}}
}void ACameraPawn::Panx(float x)
{MyCamera->AddLocalOffset(FVector(0,x,0));
}void ACameraPawn::Pany(float y)
{MyCamera->AddLocalOffset(FVector(0,0,y));
}void ACameraPawn::Back()
{MyCamera->SetRelativeLocation(FVector(0,0,0));
}

 3.在MyPlayerController里面绑定输入映射，以及响应的事件。

	virtual void SetupInputComponent();void WheelUpFunction();void WheelDownFunction();void PanX(float x);void PanY(float y);void Back();

4.绑定映射

void AMyPlayerController::SetupInputComponent()
{Super::SetupInputComponent();InputComponent->BindAction("WheelUp", IE_Pressed, this, &AMyPlayerController::WheelUpFunction);InputComponent->BindAction("WheelDown", IE_Pressed, this, &AMyPlayerController::WheelDownFunction);InputComponent->BindAction("BackXY",IE_Pressed,this,&AMyPlayerController::Back);InputComponent->BindAxis("PanX",this,&AMyPlayerController::PanX);InputComponent->BindAxis("PanY",this,&AMyPlayerController::PanY);//InputComponent->BindAction("ESCEvent", IE_Pressed, this, &AMyPlayerController::ESCEvent).bExecuteWhenPaused=true;//游戏暂停可以执行//InpuptComponent->BindAxis("PanY",this,);
}

5.响应事件，并操控控制到对应的Pawn里的函数。

void AMyPlayerController::WheelUpFunction()
{if (GetPawn()) {ACameraPawn* MyCameraPawn = Cast<ACameraPawn>(GetPawn());if (MyCameraPawn) {MyCameraPawn->Zoom(1, 10);}}
}void AMyPlayerController::WheelDownFunction()
{if (GetPawn()) {ACameraPawn* MyCameraPawn = Cast<ACameraPawn>(GetPawn());if (MyCameraPawn) {MyCameraPawn->Zoom(0, 10);}}
}void AMyPlayerController::PanX(float x)
{if (GetPawn()){ACameraPawn* MyCameraPawn = Cast<ACameraPawn>(GetPawn());if (MyCameraPawn) {MyCameraPawn->Panx(x);}}
}void AMyPlayerController::PanY(float y)
{if (GetPawn()){ACameraPawn* MyCameraPawn = Cast<ACameraPawn>(GetPawn());if (MyCameraPawn) {MyCameraPawn->Pany(y);}}
}void AMyPlayerController::Back()
{if (GetPawn()){ACameraPawn* MyCameraPawn = Cast<ACameraPawn>(GetPawn());if (MyCameraPawn) {MyCameraPawn->Back();}}
}

6.需要在ProjectSetting里面，设置使用的按键。

三.可能需要注意的

1.Pawn这里，需要Poccess。不然会控制不到。

2.SpringArm设置视角的位置。Camera最好都是相对位置为0，这样视角返回默认值可以用。

MyCamera->SetRelativeLocation(FVector(0,0,0));