Optical Zoom

绑定键位

API导航

APlayerController::PlayerCameraManager

管理摄像机

Copy1/** Camera manager associated with this Player Controller. */
2UPROPERTY(BlueprintReadOnly, Category=PlayerController)
3TObjectPtr<APlayerCameraManager> PlayerCameraManager;

APlayerCameraManager::GetFOVAngle

当前使用的FOV Field of View

Copy1/** Returns the camera's current full FOV angle, in degrees. */
2UFUNCTION(BlueprintCallable, Category = "Camera")
3virtual float GetFOVAngle() const;

APlayerCameraManager::SetFOV

设置FOV

Copy1/** 
2 * Locks the FOV to the given value.  Unlock with UnlockFOV.
3 * @param NewFOV - New full FOV angle to use, in degrees.
4 */
5virtual void SetFOV(float NewFOV);

InputComponent::BindAction<T>

若绑定键位模式为Action, 其默认回调函数形参列表为空

可以使用委托, 给出预设的其他形参

类似C++的bind

Copy 1/**
 2* Binds a delegate function to an Action defined in the project settings.
 3* Returned reference is only guaranteed to be valid until another action is bound.
 4*/
 5template< class DelegateType, class UserClass, typename... VarTypes >
 6FInputActionBinding& BindAction( const FName ActionName, const EInputEvent KeyEvent, UserClass* Object, typename DelegateType::template TMethodPtr< UserClass > Func, VarTypes... Vars )
 7{
 8    FInputActionBinding AB( ActionName, KeyEvent );
 9    AB.ActionDelegate.BindDelegate<DelegateType>(Object, Func, Vars...);
10    return AddActionBinding(MoveTemp(AB));
11}

实现

武器基类

• 瞄准镜变焦为武器相关
  
• 步枪独有
  

public

ShootThemUp: Weapon/STUBaseWeapon.h

Copy1virtual void Zoom(bool IsEnable) {}

步枪

1. 添加属性: 瞄准镜放大系数
   
   protected

ShootThemUp: Weapon/STURifleWeapon.h
   

   Copy1UPROPERTY(EditDefaultsOnly, BlueprintReadWrite)
   2float FOVZoomAngle = 50.0f;

2. 添加属性: 瞄准镜默认放大系数
   
   private

ShootThemUp: Weapon/STURifleWeapon.h
   

   Copy1float DefaultCameraFOV = 90.0f;

3. 覆写基类Zoom函数
   
   public

ShootThemUp: Weapon/STURifleWeapon.h
   

   Copy1virtual void Zoom(bool IsEnable) override;

   ShootThemUp: Weapon/STURifleWeapon.cpp
   

   Copy 1void ASTURifleWeapon::Zoom(bool IsEnable)
    2{
    3    const auto PlayerController = Cast<APlayerController>(GetController());
    4
    5    if (!PlayerController || !PlayerController->PlayerCameraManager) return;
    6
    7    if (IsEnable)
    8    {
    9        DefaultCameraFOV = PlayerController->PlayerCameraManager->GetFOVAngle();
   10    }
   11
   12    const auto NewFOV = IsEnable ? FOVZoomAngle : DefaultCameraFOV;
   13    PlayerController->PlayerCameraManager->SetFOV(NewFOV);
   14}

武器组件

作为键位绑定回调函数

public

ShootThemUp: Components/STUWeaponComponent.h

Copy1void Zoom(bool Enabled);

ShootThemUp: Components/STUWeaponComponent.cpp

Copy1void USTUWeaponComponent::Zoom(bool Enabled)
2{
3    if (CurrentWeapon)
4    {
5        CurrentWeapon->Zoom(Enabled);
6    }
7}

游戏角色

按照常规思路, 会添加两个接口ZoomIn和ZoomOff, 调用武器组件的Zoom, 来填平形参

下面给出一个回避技巧, 达到相同的效果

ShootThemUp: Player/STUPlayerCharacter.cpp

Copy1// SetupPlayerInputComponent
2
3DECLARE_DELEGATE_OneParam(FZoomInputSignature, bool);
4PlayerInputComponent->BindAction<FZoomInputSignature>("Zoom", IE_Pressed, WeaponComponent, &USTUWeaponComponent::Zoom, true);
5PlayerInputComponent->BindAction<FZoomInputSignature>("Zoom", IE_Released, WeaponComponent, &USTUWeaponComponent::Zoom, false);

问题

1. 发射器不支持瞄准镜; 保持鼠标右键不释放, 切换武器, 摄像机视角为放大
   
   ShootThemUp: Components/STUWeaponComponent.cpp
   

   Copy1// EquipWeapon
   2
   3if (CurrentWeapon)
   4{
   5    CurrentWeapon->Zoom(false);
   6    CurrentWeapon->FireStop();
   7    // ...
   8}

2. 游戏角色死亡后, 摄像机视角未解除放大
   
   ShootThemUp: Player/STUBaseCharacter.cpp
   

   Copy1// OnDeath
   2
   3WeaponComponent->Zoom(false);
   4WeaponComponent->FireStop();

和停止射击逻辑同时出现

若遇到卸载武器逻辑较为复杂的情况, 可以实现专门的UnEquip函数

查看

1. 在关卡中添加BP_STUPlayerCharacter实例
   

2. 调节Field of View参数: 数值变小, 起到放大效果