UE4C++编程入门：创建旋转立方体

根据UE4官方文档的编程快速入门&＃xff0c;通过编写C&＃43;&＃43;代码&＃xff0c;在场景中创建一个旋转的立方体。
该立方体通过一个C&＃43;&＃43;类来实现&＃xff0c;该类继承自父类Actor&＃xff0c;Actor类似于Unity的prefab&＃xff0c;可以拖到场景中。通过设置public变量&＃xff0c;可以实现类似在unity运行时&＃xff0c;修改gameobject的public参数的结果。

一、项目设置

选择blank模板&＃xff1a;

选择C&＃43;&＃43;&＃xff1a;

创建新C&＃43;&＃43;类&＃xff0c;File–> New C&＃43;&＃43; Class…

父类选择 Actor&＃xff1a;

将Actor命名为 FloatingActor&＃xff0c;然后点击 Create Class。&＃xff1a;

点击create Class后&＃xff0c;将切换到Visual Studio并编辑代码。

二、编写代码

FloatingActor.h新增代码如下&＃xff1a;

UCLASS()
class UE4_CPP_TEST_API AFloatingActor : public AActor
{GENERATED_BODY()public: UPROPERTY(EditAnywhere, BlueprintReadWrite, Category &＃61; "FloatingActor")float FloatSpeed &＃61; 20.0f;UPROPERTY(EditAnywhere, BlueprintReadWrite, Category &＃61; "FloatingActor")float RotationSpeed &＃61; 20.0f;// Sets default values for this actor&＃39;s propertiesAFloatingActor();UPROPERTY(VisibleAnywhere)UStaticMeshComponent* VisualMesh;protected:
...public:
...};


FloatingActor.cpp新增代码如下&＃xff1a;
构造函数&＃xff1a;

// Sets default values
AFloatingActor::AFloatingActor()
{VisualMesh &＃61; CreateDefaultSubobject<UStaticMeshComponent>(TEXT("Mesh"));VisualMesh->SetupAttachment(RootComponent);static ConstructorHelpers::FObjectFinder<UStaticMesh> CubeVisualAsset(TEXT("/Game/StarterContent/Shapes/Shape_Cube.Shape_Cube"));if (CubeVisualAsset.Succeeded()){VisualMesh->SetStaticMesh(CubeVisualAsset.Object);VisualMesh->SetRelativeLocation(FVector(0.0f, 0.0f, 0.0f));}// Set this actor to call Tick() every frame. You can turn this off to improve performance if you don&＃39;t need it.PrimaryActorTick.bCanEverTick &＃61; true;
}


Tick()函数&＃xff1a;

// Called every frame
void AFloatingActor::Tick(float DeltaTime)
{FVector NewLocation &＃61; GetActorLocation();FRotator NewRotation &＃61; GetActorRotation();float RunningTime &＃61; GetGameTimeSinceCreation();float DeltaHeight &＃61; (FMath::Sin(RunningTime &＃43; DeltaTime) - FMath::Sin(RunningTime));NewLocation.Z &＃43;&＃61; DeltaHeight * FloatSpeed; //按FloatSpeed调整高度float DeltaRotation &＃61; DeltaTime * RotationSpeed; //每秒旋转等于RotationSpeed的角度NewRotation.Yaw &＃43;&＃61; DeltaRotation;SetActorLocationAndRotation(NewLocation, NewRotation);Super::Tick(DeltaTime);
}


三、编译C&＃43;&＃43;代码

法一&＃xff1a;visual studio中编译

法二&＃xff1a;编辑器内编译

四、放置Actor

将actor拖到视口&＃xff0c;将Actor的 Location设置为&＃xff08;-180、0、180&＃xff09;。&＃xff1a;

五、运行结果

运行时调节Rotation Speed的效果&＃xff1a;

参考资料&＃xff1a;
https://docs.unrealengine.com/zh-CN/Programming/QuickStart/index.html