ue4 C++ 导入图片

void SDrawHouseTypeTools::OnButtonClickLoadImage()

{

       // 当前如果是在硬装模块，则可进行导入户型操作

       FHardEdMode* HardEdMode = (FHardEdMode*)GLevelEditorModeTools().GetActiveMode(FBuiltinEditorModes::EM_HardEdModeId);

       if (HardEdMode)

       {

              //打开文件夹

              TArray<FString> OpenFilenames;

              TSharedPtr<SWindow> ParentWindow = FSlateApplication::Get().GetActiveTopLevelWindow();

              void* ParentWindowHandle = (ParentWindow.IsValid() && ParentWindow->GetNativeWindow().IsValid()) ? ParentWindow->GetNativeWindow()->GetOSWindowHandle() : nullptr;

              if (ExtendFunc::OpenFileDialog(

                     ParentWindowHandle,

                     NSLOCTEXT("UIHome", "OpenReferencePictureTitle", "打开户型图片文件...").ToString(),

                     FPaths::GameDir(),

                     TEXT(""),

                     NSLOCTEXT("UIHome", "OpenReferencePictureFilter", "All Files (*.*)|*.*|户型图片文件 (*.png)|*.png|户型图片文件 (*.jpg)|*.jpg").ToString(),

                     ExtendFunc::EFileDialogFlags::None,

                     OpenFilenames))

              {

                     if (OpenFilenames.Num() > 0)

                     {

                           FString OpenFilename = OpenFilenames[0];

                           FName BrushName(*OpenFilename);

                           //传了图片路径，返回可以用来显示在runtime中的图片纹理

                           if (SpriteTexture.IsValid() && SpriteTexture->IsRooted())

                           {

                                  SpriteTexture->RemoveFromRoot();

                           }

                           // 判断图片得格式是否正确

                           SpriteTexture = TWeakObjectPtr<UTexture2D>(GetTexture2DFromDiskFile(OpenFilename));

                           if (SpriteTexture.IsValid())

                           {

                                  SpriteTexture->AddToRoot();

                                  //将数据存储并导入到画图方法中

                                  FIntPoint ImageSize = FIntPoint(SpriteTexture->GetSizeX(), SpriteTexture->GetSizeY());

                                  IHardModeModule::Get().GetImageSize() = ImageSize;

                                  TextureAlpha = 0.5;

                                  HardEdMode->OnHouseImgAlphaChanged(TextureAlpha);

                                  HardEdMode->SetHouseImg(SpriteTexture.Get(), ImageSize);

                           }

                           else

                           {

                                  FMessageDialog::Open(EAppMsgType::Ok, FText::FromString(TEXT("请导入正确格式的图片！")));

                                  OnButtonClickLoadImage();

                           }

                     }

              }

       }

       else

       {

              FMessageDialog::Open(EAppMsgType::Ok, FText::FromString(TEXT(" ")));

       }

}

//获取图片纹理

UTexture2D* SDrawHouseTypeTools::GetTexture2DFromDiskFile(const FString& FilePath)

{

       // 如果找到该文件，则返回true，否则为false

       if (!FPaths::FileExists(FilePath))

       {

              UE_LOG(LogTemp, Error, TEXT("File not found: %s"), *FilePath);

              return nullptr;

       }

       // 从文件中加载压缩的字节数据

       TArray<uint8> FileData;

       if (!FFileHelper::LoadFileToArray(FileData, *FilePath))

       {

              UE_LOG(LogTemp, Error, TEXT("Failed to load file: %s"), *FilePath);

              return nullptr;

       }

       // 使用ImageWrapper模块检测图像类型

       IImageWrapperModule& ImageWrapperModule = FModuleManager::LoadModuleChecked<IImageWrapperModule>(TEXT("ImageWrapper"));

       EImageFormat::Type ImageFormat = ImageWrapperModule.DetectImageFormat(FileData.GetData(), FileData.Num());

       if (ImageFormat == EImageFormat::Invalid)

       {

              UE_LOG(LogTemp, Error, TEXT("Unrecognized image file format: %s"), *FilePath);

              return nullptr;

       }

       // 为检测到的图像格式创建一个图像包装

       IImageWrapperPtr ImageWrapper = ImageWrapperModule.CreateImageWrapper(ImageFormat);

       if (!ImageWrapper.IsValid())

       {

              UE_LOG(LogTemp, Error, TEXT("Failed to create image wrapper for file: %s"), *FilePath);

              return nullptr;

       }

       // 解压图像数据

       const TArray<uint8>* RawData = nullptr;

       ImageWrapper->SetCompressed(FileData.GetData(), FileData.Num());

       ImageWrapper->GetRaw(ERGBFormat::BGRA, 8, RawData);

       if (RawData == nullptr)

       {

              UE_LOG(LogTemp, Error, TEXT("Failed to decompress image file: %s"), *FilePath);

              return nullptr;

       }

       // 创建纹理并上传未压缩的图像数据

       FString TextureBaseName = TEXT("Texture_") + FPaths::GetBaseFilename(FilePath);

       // UObject* Outer = nullptr;

       UTexture2D* mytexture = MyCreateTexture(*RawData, ImageWrapper->GetWidth(), ImageWrapper->GetHeight(), EPixelFormat::PF_B8G8R8A8, FName(*TextureBaseName));

       

       return mytexture;

}

UTexture2D* SDrawHouseTypeTools::MyCreateTexture(const TArray<uint8>& PixelData, int32 InSizeX, int32 InSizeY, EPixelFormat InFormat, FName BaseName)

{

       // 无耻地抄袭UTexture2D:CreateTransient一些修改

       if (InSizeX <= 0 || InSizeY <= 0 || (InSizeX % GPixelFormats[InFormat].BlockSizeX) != 0 || (InSizeY % GPixelFormats[InFormat].BlockSizeY) != 0)

       {

              return nullptr;

       }

       // 最重要的不同之处在于UTexture2D::CreateTransient:我们为新结构提供一个名称和一个所有者

       UTexture2D* NewTexture = NewObject<UTexture2D>(GetTransientPackage(), NAME_None, RF_Transient);

       NewTexture->PlatformData = new FTexturePlatformData();

       NewTexture->PlatformData->SizeX = InSizeX;

       NewTexture->PlatformData->SizeY = InSizeY;

       NewTexture->PlatformData->PixelFormat = InFormat;

       // 分配第一个纹理映射并上传像素数据

       int32 NumBlocksX = InSizeX / GPixelFormats[InFormat].BlockSizeX;

       int32 NumBlocksY = InSizeY / GPixelFormats[InFormat].BlockSizeY;

       FTexture2DMipMap* Mip = new(NewTexture->PlatformData->Mips) FTexture2DMipMap();

       Mip->SizeX = InSizeX;

       Mip->SizeY = InSizeY;

       Mip->BulkData.Lock(LOCK_READ_WRITE);

       void* TextureData = Mip->BulkData.Realloc(NumBlocksX * NumBlocksY * GPixelFormats[InFormat].BlockBytes);

       FMemory::Memcpy(TextureData, PixelData.GetData(), PixelData.Num());

       Mip->BulkData.Unlock();

       NewTexture->UpdateResource();

       return NewTexture;

}