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【UE4 基础知识】一些相关宏：Core、UBT、平台

Core 宏

主要用于反射

  • UCLASS()

  • USTRUCT()

  • UENUM()

  • UPROPERTY()

  • UFUNCTION()

  • UMETA()

  • UPARAM()

  • GENERATED_BODY() 和 GENERATED_UCLASS_BODY() 的区别 ( from UE4 C++ UCLASS构造函数易出错分析 )

    • GENERATED_BODY() (现在一般都用这个了，另外一个属于比较老的版本)
      如果定义的是GENERATED_BODY()，那么意味着我不需要使用父类的构造函数，也就是说，我不能直接使用父类的声明，但是，我需要去实现的时候，我就必须自己去声明，否则就会报错。

      UCLASS()
class MYCHARACTER_API AMyCharacter : public ACharacter
{
    GENERATED_BODY()
public:
    AMyCharacter(const FObjectInitializer& ObjectInitializer);    
};

//如果不去声明自己的构造函数，就会报错： error C2084
AMyCharacter::AMyCharacter(const FObjectInitializer& ObjectInitializer)
    : Super(ObjectInitializer)
{}

    • GENERATED_UCLASS_BODY()
      如果定义的是GENERATED_UCLASS_BODY()，那么意味着我使用父类的构造函数，也就是说，我不需要为自己声明构造函数，直接去实现父类声明那个构造函数。

      UCLASS()
class MYCHARACTER_API AMyCharacter : public ACharacter
{
    GENERATED_UCLASS_BODY()
};

AMyCharacter::AMyCharacter(const FObjectInitializer& ObjectInitializer)
    : Super(ObjectInitializer)
{}

// 如果还去声明自己的构造函数，就会报错： error C2535:
UCLASS()
class MYCHARACTER_API AMyCharacter : public ACharacter
{
    GENERATED_UCLASS_BODY()       
public:
    AMyCharacter(const FObjectInitializer& ObjectInitializer);
};

  • 可查看 Engine\Source\Runtime\CoreUObject\Public\UObject\ObjectMacros.h

  • 本文原创链接

UBT 相关

  • WITH_EDIROT (cpp)

    #if WITH_EDITOR    //是否在用编辑器编译
...
#endif

if(GIsEdior)  // GIsEdior 全局变量,是否再编辑(PIE)模式下运行

  • WITH_EDITORONLY_DATA （.h 反射需要）
    包裹 UPROPERTY()、UFunction()

    #if WITH_EDITORONLY_DATA 
UPROPERTY()
    FString ActorName;
#endif

  • 所有 \Engine\Source\Runtime\Core\Public\Misc\Build.h

    /*----------------------------------------------------------------------------
	Mandatory bridge options coming from UBT, do not modify directly!
----------------------------------------------------------------------------*/

/**
 * Whether we are compiling with the editor; must be defined by UBT
 */
#ifndef WITH_EDITOR
	#define WITH_EDITOR	0 // for auto-complete
	#error UBT should always define WITH_EDITOR to be 0 or 1
#endif

/**
 * Whether we are compiling with the engine; must be defined by UBT
 */
#ifndef WITH_ENGINE
	#define WITH_ENGINE	0 // for auto-complete
	#error UBT should always define WITH_ENGINE to be 0 or 1
#endif

运行模式相关

  • 使用实例

    #if UE_BUILD_SHIPPING
 // do mobile specific stuff
#endif

  • \Engine\Source\Runtime\Core\Public\Misc\Build.h

    /*--------------------------------------------------------------------------------
	Build configuration coming from UBT, do not modify
--------------------------------------------------------------------------------*/

// Set any configuration not defined by UBT to zero
#ifndef UE_BUILD_DEBUG
	#define UE_BUILD_DEBUG				0
#endif
#ifndef UE_BUILD_DEVELOPMENT
	#define UE_BUILD_DEVELOPMENT		0
#endif
#ifndef UE_BUILD_TEST
	#define UE_BUILD_TEST				0
#endif
#ifndef UE_BUILD_SHIPPING
	#define UE_BUILD_SHIPPING			0
#endif
#ifndef UE_GAME
	#define UE_GAME						0
#endif
#ifndef UE_EDITOR
	#define UE_EDITOR					0
#endif
#ifndef UE_BUILD_SHIPPING_WITH_EDITOR
	#define UE_BUILD_SHIPPING_WITH_EDITOR 0
#endif
#ifndef UE_BUILD_DOCS
	#define UE_BUILD_DOCS				0
#endif

/** 
 *   Whether compiling for dedicated server or not.
 */
#ifndef UE_SERVER
	#define UE_SERVER					0
#endif

平台相关

  • 使用示例

    #if PLATFORM_IOS || PLATFORM_ANDROID
 // do mobile specific stuff
#endif

// Runtime/Core/Public/HAL/PlatformProcess.h
#if PLATFORM_WINDOWS
#include "Windows/WindowsPlatformProcess.h"
#elif PLATFORM_PS4
#include "PS4/PS4Process.h"
#elif PLATFORM_XBOXONE
#include "XboxOne/XboxOneProcess.h"
#elif PLATFORM_MAC
#include "Mac/MacPlatformProcess.h"
#elif PLATFORM_IOS
#include "IOS/IOSPlatformProcess.h"
#elif PLATFORM_ANDROID
#include "Android/AndroidProcess.h"
#elif PLATFORM_HTML5
#include "HTML5/HTML5PlatformProcess.h"
#elif PLATFORM_LINUX
#include "Linux/LinuxPlatformProcess.h"
#elif PLATFORM_SWITCH
#include "Switch/SwitchPlatformProcess.h"
#endif

  • 平台宏定义 \Engine\Source\Runtime\Core\Public\HAL\Platform.h

    // define all other platforms to be zero
//@port Define the platform here to be zero when compiling for other platforms
#if !defined(PLATFORM_WINDOWS)
	#define PLATFORM_WINDOWS 0
#endif
#if !defined(PLATFORM_XBOXONE)
	#define PLATFORM_XBOXONE 0
#endif
#if !defined(PLATFORM_MAC)
	#define PLATFORM_MAC 0
	// If PLATFORM_MAC is defined these will be set appropriately in
	// MacPlatform.h
	#define PLATFORM_MAC_X86 0
	#define PLATFORM_MAC_ARM64 0
#endif
#if !defined(PLATFORM_PS4)
	#define PLATFORM_PS4 0
#endif
#if !defined(PLATFORM_IOS)
	#define PLATFORM_IOS 0
#endif
#if !defined(PLATFORM_TVOS)
	#define PLATFORM_TVOS 0
#endif
#if !defined(PLATFORM_ANDROID)
	#define PLATFORM_ANDROID 0
#endif
#if !defined(PLATFORM_ANDROID_ARM)
	#define PLATFORM_ANDROID_ARM 0
#endif
#if !defined(PLATFORM_ANDROID_ARM64)
	#define PLATFORM_ANDROID_ARM64 0
#endif
#if !defined(PLATFORM_ANDROID_X86)
	#define PLATFORM_ANDROID_X86 0
#endif
#if !defined(PLATFORM_ANDROID_X64)
	#define PLATFORM_ANDROID_X64 0
#endif
#if !defined(PLATFORM_ANDROID_VULKAN)
	#define PLATFORM_ANDROID_VULKAN 0
#endif
#if !defined(PLATFORM_ANDROIDGL4)
	#define PLATFORM_ANDROIDGL4 0
#endif
#if !defined(PLATFORM_LUMINGL4)
	#define PLATFORM_LUMINGL4 0
#endif
#if !defined(PLATFORM_LUMIN)
	#define PLATFORM_LUMIN 0
#endif
#if !defined(PLATFORM_APPLE)
	#define PLATFORM_APPLE 0
#endif
#if !defined(PLATFORM_LINUX)
	#define PLATFORM_LINUX 0
#endif
#if !defined(PLATFORM_LINUXAARCH64)
	#define PLATFORM_LINUXAARCH64 0
#endif
#if !defined(PLATFORM_SWITCH)
	#define PLATFORM_SWITCH 0
#endif
#if !defined(PLATFORM_FREEBSD)
	#define PLATFORM_FREEBSD 0
#endif
#if !defined(PLATFORM_UNIX)
	#define PLATFORM_UNIX 0
#endif
#if !defined(PLATFORM_MICROSOFT)
	#define PLATFORM_MICROSOFT 0
#endif
#if !defined(PLATFORM_HOLOLENS)
#define PLATFORM_HOLOLENS 0
#endif

参考

posted @ 2021-11-04 14:11  砥才人  阅读(3465)  评论(0)  编辑  收藏  举报