How do I convert from UTextureRenderTargetCube to UTextureCube at runtime

Development Asset Creation
, ,
1

I need to load a panorama texture and change the skybox environment at runtime.
I was doning well at previous steps.
But I failed when trying to convert from UTextureRenderTargetCube to UTextureCube after packaging project.
Here is my code:

#include "UtilityLibrary.h"
#include "Engine/TextureRenderTargetCube.h"
#include "AssetRegistry/AssetRegistryModule.h"
#include "UObject/ObjectMacros.h"
#include "UObject/UObjectBaseUtility.h"

void UUtilityLibrary::ConvertToStaticTexture(UTextureRenderTargetCube* renderTarget, FString PackagePath, FString TextureName, bool& success, UTextureCube*& outputTexture)
{
	UPackage* mPackage = CreatePackage(NULL, *PackagePath);
	UTextureCube* textureCube = renderTarget->ConstructTextureCube(mPackage, 
        TextureName, EObjectFlags::RF_Public | EObjectFlags::RF_Standalone);
	if (textureCube != nullptr) {
		outputTexture = textureCube;
		success = true;
	}
	else {
		outputTexture = nullptr;
		success = false;
	}
}

It can run in the editor. but after packaging, it always return nullptr.
I checked several tutorials, they executed the following codes, but I encountered compile error.

textureCube->MarkPackageDirty();
textureCube->GetOuter()->MarkPackageDirty();
FAssetRegistryModule::AssetCreated(textureCube);

I have no idea to solve it now.
I guess my flags settings is wrong or construct texture cube method is only editor support.