多视角系统,视角之间的切换，输入操作。无人机Pawn视角的实现

一.创建自己的PlayerController。它相当于是灵魂，穿梭在不同Pawn之间。也即是切换视角。不同输入的响应也写在这里。这样即使，都有鼠标操作，也能区分。避免了代码的重复耦合。也可以叫做视角系统。

class LZJGAMEMODE_API ALZJPlayerController : public APlayerController
{GENERATED_BODY()virtual void SetupInputComponent();void LeftButtonFunction();void DeactiveLeftButtonFunction();void RightButtonFunction();void DeactiveRightButtonFunction();void WheelUpFunction();void WheelDownFunction();void PanX(float value);void PanY(float value);void RotateX(float value);void RotateY(float value);
};

二.开始需要绑定，每一个，按键事件。对应回调那个函数。在函数里，会通过GetPawn，判断当前肉体是哪个Pawn,在对于调用此时这个Pawn的函数功能。

void ALZJPlayerController::SetupInputComponent()
{Super::SetupInputComponent();InputComponent->BindAction("LeftButtonFunction", IE_Pressed, this, &ALZJPlayerController::LeftButtonFunction);InputComponent->BindAction("LeftButtonFunction", IE_Released, this, &ALZJPlayerController::DeactiveLeftButtonFunction);InputComponent->BindAction("RightButtonFunction", IE_Pressed, this, &ALZJPlayerController::RightButtonFunction);InputComponent->BindAction("RightButtonFunction", IE_Released, this, &ALZJPlayerController::DeactiveRightButtonFunction);InputComponent->BindAction("WheelUpFunction", IE_Pressed, this, &ALZJPlayerController::WheelUpFunction);InputComponent->BindAction("WheelDownFunction", IE_Pressed, this, &ALZJPlayerController::WheelDownFunction);InputComponent->BindAxis("PanX", this, &ALZJPlayerController::PanX);InputComponent->BindAxis("PanY", this, &ALZJPlayerController::PanY);InputComponent->BindAxis("RotateX", this, &ALZJPlayerController::RotateX);InputComponent->BindAxis("RotateY", this, &ALZJPlayerController::RotateY);bShowMouseCursor = true;
}void ALZJPlayerController::LeftButtonFunction()
{if (GetPawn()) {ALZJPawn* TmpCamPawn = Cast<ALZJPawn>(GetPawn());if (TmpCamPawn) {TmpCamPawn->ActivePin();}}
}void ALZJPlayerController::DeactiveLeftButtonFunction()
{if (GetPawn()) {ALZJPawn* TmpCamPawn = Cast<ALZJPawn>(GetPawn());if (TmpCamPawn) {TmpCamPawn->DeActivePin();}}
}void ALZJPlayerController::RightButtonFunction()
{if (GetPawn()) {ALZJPawn* TmpCamPawn = Cast<ALZJPawn>(GetPawn());if (TmpCamPawn) {TmpCamPawn->ActiveRotate();}}if (GetPawn()) {ALZJTravelPawn* TmpCamPawn = Cast<ALZJTravelPawn>(GetPawn());if (TmpCamPawn) {TmpCamPawn->ActiveRotate();}}
}void ALZJPlayerController::DeactiveRightButtonFunction()
{if (GetPawn()) {ALZJPawn* TmpCamPawn = Cast<ALZJPawn>(GetPawn());if (TmpCamPawn) {TmpCamPawn->DeActiveRotate();}}if (GetPawn()) {ALZJTravelPawn* TmpCamPawn = Cast<ALZJTravelPawn>(GetPawn());if (TmpCamPawn) {TmpCamPawn->DeActiveRotate();}}
}void ALZJPlayerController::WheelUpFunction()
{if (GetPawn()) {ALZJPawn* TmpCamPawn = Cast<ALZJPawn>(GetPawn());if (TmpCamPawn) {TmpCamPawn->Zoom(1, 10);}}
}void ALZJPlayerController::WheelDownFunction()
{if (GetPawn()) {ALZJPawn* TmpCamPawn = Cast<ALZJPawn>(GetPawn());if (TmpCamPawn) {TmpCamPawn->Zoom(0, 10);}}
}void ALZJPlayerController::PanX(float value)
{if (GetPawn()) {ALZJPawn* TmpCamPawn = Cast<ALZJPawn>(GetPawn());if (TmpCamPawn) {TmpCamPawn->PanX(value);}}}void ALZJPlayerController::PanY(float value)
{if (GetPawn()) {ALZJPawn* TmpCamPawn = Cast<ALZJPawn>(GetPawn());if (TmpCamPawn) {TmpCamPawn->PanY(value);}}
}void ALZJPlayerController::RotateX(float value)
{if (GetPawn()) {ALZJPawn* TmpCamPawn = Cast<ALZJPawn>(GetPawn());if (TmpCamPawn) {TmpCamPawn->RotateX(value * 0.8f);}}if (GetPawn()) {ALZJTravelPawn* TmpCamPawn = Cast<ALZJTravelPawn>(GetPawn());if (TmpCamPawn) {TmpCamPawn->RotateX(value * 0.2f);}}
}void ALZJPlayerController::RotateY(float value)
{if (GetPawn()) {ALZJPawn* TmpCamPawn = Cast<ALZJPawn>(GetPawn());if (TmpCamPawn) {TmpCamPawn->RotateY(value * 0.8f);}}if (GetPawn()) {ALZJTravelPawn* TmpCamPawn = Cast<ALZJTravelPawn>(GetPawn());if (TmpCamPawn) {TmpCamPawn->RotateY(value * 0.2f);}}
}

三.无人机视角

1.这里说一下，其中之一的无人机视角。如果肉体是无人机。这个无人机是如何实现的。

安装碰撞盒，用与碰撞。模型不必多说。还有两个物理喷射器的指针，因为我们要从物理上模仿，这个无人机。下面分别是物理银子的参数，模型数组，以及旋转螺旋桨动画函数的声明。

UCLASS()
class WXDRONE_API ADrone : public APawn
{GENERATED_BODY()public:// Sets default values for this pawn's propertiesADrone();UPROPERTY(EditAnywhere)class UBoxComponent* OutCollision;//碰撞包围盒//如果是指针 VisibleAnywhere 和 EditAnywhere 差不多UPROPERTY(VisibleAnywhere)class UStaticMeshComponent* Mesh;//使用前置声明避免头文件增加复杂度UPROPERTY(VisibleAnywhere)class UStaticMeshComponent* Paddle1;UPROPERTY(VisibleAnywhere)class UStaticMeshComponent* Paddle2;UPROPERTY(VisibleAnywhere)class UStaticMeshComponent* Paddle3;UPROPERTY(VisibleAnywhere)class UStaticMeshComponent* Paddle4;UPROPERTY(VisibleAnywhere)class UPhysicsThrusterComponent* UpThruster;UPROPERTY(VisibleAnywhere)class UPhysicsThrusterComponent* ForwardThruster;UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Init")float LiftAcc = 20000.0f;UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Init")float LiftThrustMax = 2000.0f;UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Init")float ForwardAcc = 5000.0f;UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Init")float ForwardThrustMax = 2000.0f;UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Init")float TurnStrength = 500000.0f;UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Init")float PaddleRotateSpeed = 500.0f;//UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Init")//TSubclassOf<class AMissle> Bullet;
protected:// Called when the game starts or when spawnedvirtual void BeginPlay() override;void Lift(float aixs);void Forward(float aixs);void Turn(float aixs);void Fire();//定义了一个数组存储所有螺旋桨TArray<UStaticMeshComponent*> Paddles;//旋转螺旋桨void RotatePaddle(float dt);
public:// Called every framevirtual void Tick(float DeltaTime) override;// Called to bind functionality to inputvirtual void SetupPlayerInputComponent(class UInputComponent* PlayerInputComponent) override;UFUNCTION(BlueprintCallable)void SetPossess();
};

无人机功能的实现，首先包含需要的头文件，和构造时初始化组件，设置位置参数等。

#include "Drone.h"
#include "Components/StaticMeshComponent.h"
#include "Components/BoxComponent.h"
#include "PhysicsEngine/PhysicsThrusterComponent.h"
#include "Kismet/KismetMathLibrary.h"
#include <Kismet/GameplayStatics.h>ADrone::ADrone()
{// 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;OutCollision = CreateDefaultSubobject<UBoxComponent>(TEXT("OutCollision"));RootComponent = OutCollision;OutCollision->SetBoxExtent(FVector(90.0f, 90.0f, 40.0f));OutCollision->SetSimulatePhysics(true);OutCollision->BodyInstance.bLockXRotation = true;OutCollision->BodyInstance.bLockYRotation = true;//UE的C++中，UE自己的类是由UE自己来管理生命周期的，如果要创建UE的对象需要使用专门的对应的函数来创建Mesh = CreateDefaultSubobject<UStaticMeshComponent>(TEXT("Mesh"));Mesh->SetupAttachment(OutCollision);Paddle1 = CreateDefaultSubobject<UStaticMeshComponent>(TEXT("Paddle1"));Paddle2 = CreateDefaultSubobject<UStaticMeshComponent>(TEXT("Paddle2"));Paddle3 = CreateDefaultSubobject<UStaticMeshComponent>(TEXT("Paddle3"));Paddle4 = CreateDefaultSubobject<UStaticMeshComponent>(TEXT("Paddle4"));Paddle1->SetupAttachment(Mesh, TEXT("Paddle1"));Paddle2->SetupAttachment(Mesh, TEXT("Paddle2"));Paddle3->SetupAttachment(Mesh, TEXT("Paddle3"));Paddle4->SetupAttachment(Mesh, TEXT("Paddle4"));//将元素加入到数组Paddles.Add(Paddle1);Paddles.Add(Paddle2);Paddles.Add(Paddle3);Paddles.Add(Paddle4);UpThruster = CreateDefaultSubobject<UPhysicsThrusterComponent>(TEXT("UpThruster"));UpThruster->SetupAttachment(RootComponent);UpThruster->ThrustStrength = 980.0f;UpThruster->SetAutoActivate(true);UpThruster->SetWorldRotation(UKismetMathLibrary::MakeRotFromX(-this->GetActorUpVector()));ForwardThruster = CreateDefaultSubobject<UPhysicsThrusterComponent>(TEXT("ForwardThruster"));ForwardThruster->SetupAttachment(RootComponent);ForwardThruster->ThrustStrength = 0.0f;ForwardThruster->SetAutoActivate(true);ForwardThruster->SetWorldRotation(UKismetMathLibrary::MakeRotFromX(-this->GetActorForwardVector()));}

然后，在Tick函数里，做动画。螺旋桨动画，和前倾，旋转等。因为Tick是和帧数相关的循环。不会出现明显抖动。如果用定时器，就有可能卡帧抖动。

// Called every frame
void ADrone::Tick(float DeltaTime)
{Super::Tick(DeltaTime);APlayerController* tmpPC = UGameplayStatics::GetPlayerController(GetWorld(), 0);APawn* tmpPawn = tmpPC->GetPawn();if (tmpPawn) {ADrone* TmpCamPawn = Cast<ADrone>(tmpPawn);if (TmpCamPawn) {//松开的时候可以维持悬停if (InputComponent->IsValidLowLevel()){if (FMath::Abs(InputComponent->GetAxisValue(TEXT("Lift"))) < 0.000001f){UpThruster->ThrustStrength = 980.0f;}//没有输入就取消前进推力if (FMath::Abs(InputComponent->GetAxisValue(TEXT("Forward"))) < 0.000001f){ForwardThruster->ThrustStrength = 0.0f;}}//调用旋转螺旋桨RotatePaddle(DeltaTime);//复原倾斜度float pitch = Mesh->GetRelativeRotation().Pitch;if (FMath::Abs(pitch) > KINDA_SMALL_NUMBER){Mesh->AddRelativeRotation(FRotator(-pitch * DeltaTime, 0.0f, 0.0f));if (FMath::Abs(Mesh->GetRelativeRotation().Pitch) <= KINDA_SMALL_NUMBER){Mesh->SetRelativeRotation(FRotator(0.0f, 0.0f, 0.0f));}}}}}

绑定输入，因为这个输入是特殊的，没有其它的Pawn和它相同。所以就写在Pawn肉体上，其实写在灵魂PlayerController上也可以。让后就是，通过物理喷射器，向前喷射多大的力，向上喷射多大的力，让无人机在移动上模仿物理效果，结合动画，就完成了无人机。这里要将碰撞的阻尼系数，勾上。不然没有摩擦力，无人机收到喷射，就会一直加速，越来越快。停不下来。

// Called to bind functionality to input
void ADrone::SetupPlayerInputComponent(UInputComponent* PlayerInputComponent)
{Super::SetupPlayerInputComponent(PlayerInputComponent);//轴事件函数不管有没有输入事件，都会每帧调用PlayerInputComponent->BindAxis(TEXT("Lift"), this, &ADrone::Lift);PlayerInputComponent->BindAxis(TEXT("Forward"), this, &ADrone::Forward);PlayerInputComponent->BindAxis(TEXT("Turn"), this, &ADrone::Turn);PlayerInputComponent->BindAction(TEXT("Fire"), IE_Pressed, this, &ADrone::Fire);}void ADrone::SetPossess()
{APlayerController* tmpPC = UGameplayStatics::GetPlayerController(GetWorld(), 0);if (tmpPC->IsValidLowLevel()){tmpPC->Possess(this);}
}void ADrone::Lift(float aixs)
{if (aixs != 0){UpThruster->ThrustStrength += aixs * LiftAcc * GetWorld()->DeltaTimeSeconds;UpThruster->ThrustStrength = FMath::Clamp(UpThruster->ThrustStrength, -LiftThrustMax, LiftThrustMax);}}void ADrone::Forward(float aixs)
{ForwardThruster->ThrustStrength += aixs * ForwardAcc * GetWorld()->DeltaTimeSeconds;ForwardThruster->ThrustStrength = FMath::Clamp(ForwardThruster->ThrustStrength, -ForwardThrustMax, ForwardThrustMax);float pitch = FMath::Abs(Mesh->GetRelativeRotation().Pitch);if (pitch < 30.0f){Mesh->AddRelativeRotation(FRotator(-100.0f * aixs * GetWorld()->DeltaTimeSeconds, 0.0f, 0.0f));}
}void ADrone::Turn(float aixs)
{OutCollision->AddTorqueInDegrees(-this->GetActorUpVector() * TurnStrength * aixs);
}void ADrone::Fire()
{//FTransform firetransform = Mesh->GetSocketTransform(TEXT("FireSocket"));//UClass* bullet = StaticLoadClass(AMissle::StaticClass(), NULL, TEXT("Blueprint'/Game/MyMissle.MyMissle_C'"));//AActor* bullet = Cast<AActor>(StaticLoadObject(AMissle::StaticClass(), NULL, TEXT("/Game/MyMissle")));//bullet->SetActorTransform(firetransform);//GetWorld()->SpawnActor<AMissle>(bullet, firetransform);
}void ADrone::RotatePaddle(float dt)
{for (auto paddle : Paddles){paddle->AddRelativeRotation(FRotator(0.0f, dt * PaddleRotateSpeed, 0.0f));}
}