最简单的UE4C++教程——绘制UE4辅助调试的形状【六】

 【原教程是基于 UE 4.18&＃xff0c;我是基于 UE 4.25】

英文原地址

接上一节&＃xff0c;在本教程中&＃xff0c;我们将绘制 DrawDebugHelpers.h 提供的多个调试形状。DrawDebugHelpers.h 包含的相关的所有内容都是由 UE4 提供的。

创建一个新的 C&＃43;&＃43;  Actor 子类并将其命名为 MyDrawDebugHelpers 。在头文件中&＃xff0c;我们将在 .h 中声明将在 .cpp 文件中使用的变量&＃xff0c;它们也可以在编辑器中进行编辑。我们将创建一个FVectors&＃xff0c;一个 FMatrix&＃xff0c;一个 FBox&＃xff0c;和一个 FTransform。

该头文件代码如下&＃xff1a;

#pragma once#include "CoreMinimal.h"
#include "GameFramework/Actor.h"
#include "MyDrawDebugHelpers.generated.h"UCLASS()
class UNREALCPP_API AMyDrawDebugHelpers : public AActor
{GENERATED_BODY()public: // Sets default values for this actor&＃39;s propertiesAMyDrawDebugHelpers();protected:// Called when the game starts or when spawnedvirtual void BeginPlay() override;public: // Called every framevirtual void Tick(float DeltaTime) override;// declare location variablesUPROPERTY(EditAnywhere, Category &＃61; "Locations")FVector LocationOne;UPROPERTY(EditAnywhere, Category &＃61; "Locations")FVector LocationTwo;UPROPERTY(EditAnywhere, Category &＃61; "Locations")FVector LocationThree;UPROPERTY(EditAnywhere, Category &＃61; "Locations")FVector LocationFour;UPROPERTY(EditAnywhere, Category &＃61; "Locations")FVector LocationFive;UPROPERTY(EditAnywhere, Category &＃61; "Locations")FMatrix CircleMatrix;UPROPERTY(EditAnywhere, Category &＃61; "Locations")FBox MyBox;UPROPERTY(EditAnywhere, Category &＃61; "Locations")FTransform MyTransform;};

同时别忘了还要 include 头文件 DrawDebugHelpers.h 

#include "MyDrawDebugHelpers.h"
// include draw debu helpers header file
#include "DrawDebugHelpers.h"

在.cpp文件中&＃xff0c;我们将首先为变量指定默认值。下面是我们将为默认值添加的初始化代码。

// Sets default values
AMyDrawDebugHelpers::AMyDrawDebugHelpers()
{// 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;// init variables with valuesLocationOne &＃61; FVector(0,0,600);LocationTwo &＃61; FVector(0,-600,600);LocationThree &＃61; FVector(0,600,600);LocationFour &＃61; FVector(-300,0,600);LocationFive &＃61; FVector(-400,-600,600);MyBox &＃61; FBox(FVector(0,0,0), FVector(200,200,200));
}

接下来&＃xff0c;我们将在 BeginPlay() 函数中绘制许多不同的形状。

下面是我们将添加到 BeginPlay() 来绘制所有形状的函数。

// Called when the game starts or when spawned
void AMyDrawDebugHelpers::BeginPlay()
{Super::BeginPlay();DrawDebugPoint(GetWorld(), LocationOne, 200, FColor(52,220,239), true);DrawDebugSphere(GetWorld(), LocationTwo, 200, 26, FColor(181,0,0), true, -1, 0, 2);DrawDebugCircle(GetWorld(), CircleMatrix, 200, 50, FColor(0,104,167), true, -1, 0, 10);DrawDebugCircle(GetWorld(), LocationFour, 200, 50, FColor(0,0,0), true, -1, 0, 10);DrawDebugSolidBox(GetWorld(), MyBox, FColor(20, 100, 240), MyTransform, true);DrawDebugBox(GetWorld(), LocationFive, FVector(100,100,100), FColor::Purple, true, -1, 0, 10);DrawDebugLine(GetWorld(), LocationTwo, LocationThree, FColor::Emerald, true, -1, 0, 10);DrawDebugDirectionalArrow(GetWorld(), FVector(-300, 600, 600), FVector(-300, -600, 600), 120.f, FColor::Magenta, true, -1.f, 0, 5.f);DrawDebugCrosshairs(GetWorld(), FVector(0,0,1000), FRotator(0,0,0), 500.f, FColor::White, true, -1.f, 0);}

编译代码。将你的新 Actor 实例对象拖放到场景中&＃xff0c;则形状将在游戏中绘制。同时还可以在 Actor 的详细信息面板中编辑那些变量。

下面是最终的 .cpp 代码。

#include "MyDrawDebugHelpers.h"
// include draw debu helpers header file
#include "DrawDebugHelpers.h"// Sets default values
AMyDrawDebugHelpers::AMyDrawDebugHelpers()
{// 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;// init variables with valuesLocationOne &＃61; FVector(0,0,600);LocationTwo &＃61; FVector(0,-600,600);LocationThree &＃61; FVector(0,600,600);LocationFour &＃61; FVector(-300,0,600);LocationFive &＃61; FVector(-400,-600,600);MyBox &＃61; FBox(FVector(0,0,0), FVector(200,200,200));
}// Called when the game starts or when spawned
void AMyDrawDebugHelpers::BeginPlay()
{Super::BeginPlay();DrawDebugPoint(GetWorld(), LocationOne, 200, FColor(52,220,239), true);DrawDebugSphere(GetWorld(), LocationTwo, 200, 26, FColor(181,0,0), true, -1, 0, 2);DrawDebugCircle(GetWorld(), CircleMatrix, 200, 50, FColor(0,104,167), true, -1, 0, 10);DrawDebugCircle(GetWorld(), LocationFour, 200, 50, FColor(0,0,0), true, -1, 0, 10);DrawDebugSolidBox(GetWorld(), MyBox, FColor(20, 100, 240), MyTransform, true);DrawDebugBox(GetWorld(), LocationFive, FVector(100,100,100), FColor::Purple, true, -1, 0, 10);DrawDebugLine(GetWorld(), LocationTwo, LocationThree, FColor::Emerald, true, -1, 0, 10);DrawDebugDirectionalArrow(GetWorld(), FVector(-300, 600, 600), FVector(-300, -600, 600), 120.f, FColor::Magenta, true, -1.f, 0, 5.f);DrawDebugCrosshairs(GetWorld(), FVector(0,0,1000), FRotator(0,0,0), 500.f, FColor::White, true, -1.f, 0);}// Called every frame
void AMyDrawDebugHelpers::Tick(float DeltaTime)
{Super::Tick(DeltaTime);}

最终效果如下