Creating a Libtorch Project

Oct 13, 2025 by thesweetdesigns.com 29 views

Introduction

Unreal Engine 5 (UE5) is a powerful game engine that provides a wide range of features for building high-performance, visually stunning games and experiences. However, when it comes to incorporating machine learning capabilities into your project, you may need to include external libraries such as Libtorch. In this article, we will guide you through the process of including Libtorch in your UE5 project.

Prerequisites

Before we begin, make sure you have the following prerequisites:

Unreal Engine 5 installed on your system
C++ programming knowledge
Familiarity with the UE5 project structure
Libtorch installed on your system

Step 1: Setting up Libtorch

To include Libtorch in your UE5 project, you need to set it up first. Here's how to do it:

Installing Libtorch

You can install Libtorch using the following command:

pip install torch torchvision

Creating a Libtorch Project

Create a new project in your preferred IDE (e.g., Visual Studio Code) and create a new C++ project. Add the following code to your main.cpp file to test if Libtorch is working correctly:

#include <torch/torch.h>
int main() 
torch:Tensor tensor = torch::ones({2, 2);
std::cout << tensor << std::endl;
return 0;
}

Compile and run the project to ensure that Libtorch is working correctly.

Step 2: Creating a UE5 Project

Create a new UE5 project using the Unreal Engine Launcher. Choose the "Third-Person" template and create a new project.

Step 3: Adding Libtorch to UE5 Project

To add Libtorch to your UE5 project, you need to create a new C++ class that will handle the Libtorch functionality. Here's how to do it:

Creating a New C++ Class

Create a new C++ class in your UE5 project by right-clicking on the "Source" folder and selecting "New C++ Class". Name the class "LibtorchClass".

Adding Libtorch to the Class

Add the following code to your LibtorchClass.h file:

#pragma once
#include "CoreMinimal.h"
#include "GameFramework/Actor.h"
#include "LibtorchClass.h"
#include <torch/torch.h>
class LIBTORCH_API ALibtorchClass : public AActor
{
GENERATED_BODY()
public:
// Sets default values for this actor's properties
ALibtorchClass();
protected:
// Called when the game starts or when spawned
virtual void BeginPlay() override;
public:
// Called every frame
virtual void Tick(float DeltaTime) override;
void TestLibtorch();

};

Add the following code to your LibtorchClass.cpp file:

#include "LibtorchClass.h"
ALibtorchClass::ALibtorchClass()
{
// Set this actor to call Tick() every frame.
PrimaryActorTick.bCanEverTick = true;
// ... other code ...

}
void ALibtorchClass::BeginPlay()
{
Super::BeginPlay();
// ... other code ...

}
void ALibtorchClass::Tick(float DeltaTime)
{
Super::Tick(DeltaTime);
// ... other code ...

}
void ALibtorchClass::TestLibtorch()

torch:Tensor tensor = torch::ones({2, 2);
std::cout << tensor << std::endl;
}

Step 4: Compiling the Project

To compile the project, you need to add the Libtorch library to your UE5 project. Here's how to do it:

Adding Libtorch to the Project

Add the following code to your Build.cs file:

using UnrealBuildTool;
using System.IO;
public class LibtorchClass : ModuleRules
{
public LibtorchClass(TargetInfo Target)
{
PublicDependencyModuleNames.AddRange(new string[] { "Core", "CoreUObject", "Engine", "InputCore" });
    PrivateDependencyModuleNames.AddRange(new string[] { &quot;Libtorch&quot; });

    PublicIncludePaths.AddRange(new string[] { &quot;Libtorch&quot; });

    PrivateIncludePaths.AddRange(new string[] { &quot;Libtorch&quot; });

    PublicDependencyModuleNames.Add(&quot;Libtorch&quot;);
}

}

Step 5: Running the Project

To run the project, you need to create a new blueprint class that will call the TestLibtorch function. Here's how to do it:

Creating a New Blueprint Class

Create a new blueprint class in your UE5 project by right-clicking on the "Blueprints" folder and selecting "New Blueprint Class". Name the class "LibtorchBlueprint".

Adding the `TestLibtorch` Function

Add the following code to your LibtorchBlueprint.h file:

#pragma once
#include "CoreMinimal.h"
#include "GameFramework/Actor.h"
#include "LibtorchBlueprint.h"
#include "LibtorchClass.h"
class LIBTORCH_API ALibtorchBlueprint : public AActor
{
GENERATED_BODY()
public:
// Sets default values for this actor's properties
ALibtorchBlueprint();
protected:
// Called when the game starts or when spawned
virtual void BeginPlay() override;
public:
// Called every frame
virtual void Tick(float DeltaTime) override;
void TestLibtorch();

};

Add the following code to your LibtorchBlueprint.cpp file:

#include "LibtorchBlueprint.h"
ALibtorchBlueprint::ALibtorchBlueprint()
{
// Set this actor to call Tick() every frame.
PrimaryActorTick.bCanEverTick = true;
// ... other code ...

}
void ALibtorchBlueprint::BeginPlay()
{
Super::BeginPlay();
// ... other code ...

}
void ALibtorchBlueprint::Tick(float DeltaTime)
{
Super::Tick(DeltaTime);
// ... other code ...

}
void ALibtorchBlueprint::TestLibtorch()
{
ALibtorchClass* libtorchClass = Cast<ALibtorchClass>(GetWorld()->GetFirstActor());
if (libtorchClass != nullptr)
{
libtorchClass->TestLibtorch();
}
}

Conclusion

In this article, we have shown you how to include Libtorch in your Unreal Engine 5 project. We have created a new C++ class that handles the Libtorch functionality and added it to the project. We have also created a new blueprint class that calls the TestLibtorch function. With these steps, you should be able to include Libtorch in your UE5 project and start using its machine learning capabilities.

Troubleshooting

If you encounter any errors during the process, here are some troubleshooting tips:

Make sure that you have installed Libtorch correctly and that it is working correctly.
Make sure that you have added the Libtorch library to your UE5 project correctly.
Make sure that you have created the new C++ class and blueprint class correctly.
Make sure that you have added the TestLibtorch function to the blueprint class correctly.

Future Work

In the future, we plan to add more features to the Libtorch class, such as support for different types of neural networks and more advanced machine learning algorithms. We also plan to add more examples and tutorials to help developers get started with using Libtorch in their UE5 projects.

References

License

Q: What is Libtorch and why do I need it in my UE5 project?

A: Libtorch is a C++ API for PyTorch, a popular machine learning library. You need it in your UE5 project if you want to incorporate machine learning capabilities into your game or application.

Q: How do I install Libtorch in my UE5 project?

A: To install Libtorch in your UE5 project, you need to follow these steps:

Install Libtorch using pip: pip install torch torchvision
Create a new C++ class in your UE5 project that will handle the Libtorch functionality
Add the Libtorch library to your UE5 project by adding the following code to your Build.cs file: PrivateDependencyModuleNames.AddRange(new string[] { "Libtorch" });
Compile and run the project to ensure that Libtorch is working correctly

Q: How do I add Libtorch to my UE5 project if I'm using a blueprint class?

A: To add Libtorch to your UE5 project if you're using a blueprint class, you need to follow these steps:

Create a new blueprint class in your UE5 project that will call the TestLibtorch function
Add the TestLibtorch function to the blueprint class that will call the Libtorch functionality
Add the Libtorch library to your UE5 project by adding the following code to your Build.cs file: PrivateDependencyModuleNames.AddRange(new string[] { "Libtorch" });
Compile and run the project to ensure that Libtorch is working correctly

Q: What are some common errors that I might encounter when including Libtorch in my UE5 project?

A: Some common errors that you might encounter when including Libtorch in your UE5 project include:

Missing Libtorch library: Make sure that you have installed Libtorch correctly and that it is working correctly.
Incorrect Libtorch library version: Make sure that you have the correct version of Libtorch installed.
Missing C++ class or blueprint class: Make sure that you have created the new C++ class or blueprint class correctly.
Missing TestLibtorch function: Make sure that you have added the TestLibtorch function to the blueprint class correctly.

Q: How do I troubleshoot issues with Libtorch in my UE5 project?

A: To troubleshoot issues with Libtorch in your UE5 project, you can try the following:

Check the UE5 logs for errors: The UE5 logs can provide valuable information about any errors that occur when including Libtorch in your project.
Check the Libtorch documentation: The Libtorch documentation can provide information about how to use Libtorch correctly.
Check online forums and communities: Online forums and communities can provide information and support from other developers who have encountered similar issues.

Q: What are some best practices for including Libtorch in my UE5 project?

A: Some best practices for including Libtorch in your UE5 project include:

Use the correct version of Libtorch: Make sure that you have the correct version of Libtorch installed.
Use the correct C++ class or blueprint class: Make sure that you have created the new C++ class or blueprint class correctly.
Use the correct TestLibtorch function: Make sure that you have added the TestLibtorch function to the blueprint class correctly.
Test the project thoroughly: Make sure that the project is working correctly before releasing it.

Q: Can I use Libtorch with other machine learning libraries in my UE5 project?

A: Yes, you can use Libtorch with other machine learning libraries in your UE5 project. However, you may need to modify the code to work with the other libraries.

Q: Is Libtorch compatible with other UE5 features?

A: Yes, Libtorch is compatible with other UE5 features. However, you may need to modify the code to work with the other features.

Q: Can I use Libtorch in a UE5 project that is not a game?

A: Yes, you can use Libtorch in a UE5 project that is not a game. Libtorch can be used in a variety of applications, including simulations, visualizations, and more.

Q: How do I get support for Libtorch in my UE5 project?

A: You can get support for Libtorch in your UE5 project by:

Checking the UE5 documentation: The UE5 documentation can provide information about how to use Libtorch correctly.
Checking online forums and communities: Online forums and communities can provide information and support from other developers who have encountered similar issues.
Contacting Epic Games: Epic Games provides support for UE5 and can help with any issues you may encounter when including Libtorch in your project.