[游戏开发]虚幻4 游戏控制摄像头

游戏控制多个摄像机的切换

一、两个摄像机的切换
官方文档
二、多个摄像机的切换
代码实现

//CameraDirector.h
#include "CoreMinimal.h"
#include "GameFramework/Actor.h"
#include "CameraDirector.generated.h"

UCLASS()
class FLOATOBJECT_API ACameraDirector : public AActor
{
	GENERATED_BODY()

public:
	// Sets default values for this actor's properties
	ACameraDirector();

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

public:
	// Called every frame
	virtual void Tick(float DeltaTime) override;
	/*UPROPERTY(EditAnywhere)
		AActor* CameraOne;
	UPROPERTY(EditAnywhere)
		AActor* CameraTwo;*/

	float TimeToNextCameraChange;//在UE4中c++会自动初始化为0.0

	UPROPERTY(EditAnywhere)//在编辑器中可以编辑
		AActor* Cameras[6];//设置数组用于存放多个摄像机
};

//CameraDirector.cpp
#include "CameraDirector.h"
#include "Kismet/GameplayStatics.h"
int i = 0;
// Sets default values
ACameraDirector::ACameraDirector()
{
 	// Set this actor to call Tick() every frame.  You can turn this off to improve performance if you don't need it.
	PrimaryActorTick.bCanEverTick = true;

}

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

// Called every frame
void ACameraDirector::Tick(float DeltaTime)//每秒调用60次，一秒=60帧。
{
	Super::Tick(DeltaTime);
    //摄像机停留时间2.0s
    const float TimeBetweenCameraChanges = 2.0f;
    //摄像机平滑过渡时间0.75s
    const float SmoothBlendTime = 0.75f;
    /*逻辑讲解：
    开始的时候为0
    然后减去0.01等于-0.01
    判断小于0就执行
    -0.01+2=1.99
    然后不断循环1.99-0.01，循环199次（1.99/0.01)持续时间3秒左右(199/60)
    直到小于0之后再执行下面的代码
    进行遍历
    */
    TimeToNextCameraChange -= DeltaTime;//DeltaTime=1/60s
    if (TimeToNextCameraChange <= 0.0f)
    {
        TimeToNextCameraChange += TimeBetweenCameraChanges;

        // 查找处理本地玩家控制的actor,GetPlayerController获取玩家控制器
        APlayerController* OurPlayerController = UGameplayStatics::GetPlayerController(this, 0);
        if (OurPlayerController)
        {
           //遍历摄像机
               while ((OurPlayerController->GetViewTarget() != Cameras[i])&& (Cameras[i] != nullptr)&&i<6)
                {
                    // 线性地混合到摄像机2。
                    OurPlayerController->SetViewTargetWithBlend(Cameras[i], SmoothBlendTime);
                    i++;
                    break;
                }
                             
        }
    }
    if (i == 6)
        i = 0;//当遍历到第6个摄像机时，重新设为0从头遍历
}