UE4截图方式一（利用USceneCaptureComponent2D组件截图）（C++程序）

作者：AllinToyou | 2024-02-18 11:04:03

踩

uscenecapturecomponent2d


#include "Components/SceneCaptureComponent2D.h"//SceneCaptureComponent2D组件的头文件
#include "Engine/TextureRenderTarget2D.h"//TextureRenderTarget2D组件的头文件
#include "Engine/World.h"//GetWord()方法所需要的头文件
#include "TimerManager.h"//定时器所需要的头文件
#include "Modules/ModuleManager.h"//Fmodule头文件
//与图片相关的头文件
#include "IImageWrapperModule.h"
#include "IImageWrapper.h"
#include "Misc/FileHelper.h"
#include "ImageUtils.h"

以上的头文件可以从UE4官网的C++ API文档上可以找到

5、ScreenShot.h文件中添加代码

声明一个USceneCaptureComponent2D组件，并且暴露在蓝图中


UPROPERTY(Category = Default, VisibleAnywhere, BlueprintReadOnly)
class	USceneCaptureComponent2D* CaptureComponent2D;// 声明一个2D截图的组件USceneCaptureComponent2D这个

声明两个自定义的函数


UFUNCTION(BlueprintCallable)
void ScreenShotToImage(const FString& InImagePath,const FVector2D& InRangeSize);//将截屏转换为相片
UFUNCTION(BlueprintCallable)
void ColorToImage(const FString& InImagePath, TArray<FColor>InColor,int32 InWidth,int32 InHight);//将颜色数据提取

6、在ScreenShot.cpp文件中添加代码实现以上两个函数

在构造函数中创建一下所需要的组件


AScreenShot::AScreenShot()
{
 	// 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;
	RootComponent = CreateDefaultSubobject<USceneComponent>(TEXT("RootComponent"));// 创建可附加内容的虚拟根组件。
	CaptureComponent2D = CreateDefaultSubobject<USceneCaptureComponent2D>(TEXT("CaptureComponent2D"));	// 创建2D相机
	CaptureComponent2D->SetupAttachment(RootComponent);//将CaptureComponent2D绑定到RootComponent组件
 
}

ScreenShotToImage函数的实现


void AScreenShot::ScreenShotToImage(const FString& InImagePath, const FVector2D& InRangeSize)
{
 
	
	if (CaptureComponent2D && CaptureComponent2D->TextureTarget)
	{
		
		auto Lab = [=]()  // 简单自动类型推断
		{
			//获取randerTarget贴图资源  将颜色值全部放入FTextureRenderTargetResource中
			FTextureRenderTargetResource* TextureRenderTargetResource = CaptureComponent2D->TextureTarget->GameThread_GetRenderTargetResource();
			int32 Width = CaptureComponent2D->TextureTarget->SizeX;//获取高度
			int32 Height = CaptureComponent2D->TextureTarget->SizeY;//获取宽度
			TArray<FColor> OutData;//声明一个Fcolor数组
			TextureRenderTargetResource->ReadPixels(OutData);  //读取像素点
 
			ColorToImage(InImagePath, OutData, Width, Height);//写入到本地存成图片
		};
		
		FTimerHandle TimerHandle;//定义一个定时器
		//0.001f后再解析图片写入本地  防止掉帧
		GetWorld()->GetTimerManager().SetTimer(TimerHandle, Lab, 0.001f, false,0);
 
			
	}
	
}

ColorToImage函数实现


void AScreenShot::ColorToImage(const FString& InImagePath, TArray<FColor> InColor, int32 InWidth, int32 InHight)
{
 
	IImageWrapperModule& ImageWrapperModule = FModuleManager::LoadModuleChecked<IImageWrapperModule>("ImageWrapper");
	FString	Ex = FPaths::GetExtension(InImagePath);
	if (Ex.Equals(TEXT("jpg"),ESearchCase::IgnoreCase)|| Ex.Equals(TEXT("jpeg"), ESearchCase::IgnoreCase))
	{
		TSharedPtr<IImageWrapper>ImageWrapper = ImageWrapperModule.CreateImageWrapper(EImageFormat::JPEG);
		//往本地写，获取颜色数据，获取尺寸，获取长度，高度，格式rgb,8位
		if (ImageWrapper->SetRaw(InColor.GetData(),InColor.GetAllocatedSize(),InWidth,InHight,ERGBFormat::BGRA,8))
		{
			FFileHelper::SaveArrayToFile(ImageWrapper->GetCompressed(100), *InImagePath);
		}
	}
	else
	{
		TArray<uint8>OutPNG;
		
		for (FColor&color:InColor)
		{
			color.A = 255;//不写的画截屏的图片都是透明通道，就是透明的
		}
		FImageUtils::CompressImageArray(InWidth, InHight, InColor, OutPNG);
		FFileHelper::SaveArrayToFile(OutPNG, *InImagePath);
 
	}
 
}