Build Instructions for CARLA Digital Twins Plugin (UE 5)

Prerequisites

• Unreal Engine 5 installed
• Git installed
• Operating System: Linux or Windows
• Enable Python Editor Script Plugin
  To enable:
  1. Open Unreal Engine 5.
  2. Go to Edit > Plugins.
  3. In the Scripting section, find "Python Editor Script Plugin".
  4. Check the box to enable it.
  5. Restart the editor when prompted.

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Common Setup Steps (Linux & Windows)

1. Create a new Unreal Engine 5 project. It must be a blank C++ project. We recommend removing starter content.

2. Close the Unreal Editor.

3. Open your project directory in your file explorer.

4. Inside the project root, create a folder named Plugins if it doesn't already exist.

5. Open a terminal (Linux) or CMD/PowerShell (Windows), navigate to the Plugins folder, and clone the Digital Twins plugin:

   git clone -b ue5-digitaltwins https://github.com/carla-simulator/carla-digitaltwins.git

6. Navigate into the cloned folder:

   cd carla-digitaltwins

7. Run the setup script:

   • On Linux:

     ./Setup.sh

   • On Windows (on an X64 Native Tools Command Prompt for VS 2022):

     Setup.bat

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Linux Build Instructions

1. From the project root directory, run:

   make <ProjectName>Editor

   Replace <ProjectName> with the actual name of your Unreal project.

2. Once compiled, double click on ProjectName.uproject

Mitsuba support

We provide a road mesh optimization pipeline using Mitsuba, an inverse rendering library integrated in DigitalTwins for road refinement. This option is currently only available for Ubuntu. It requires the use of aerial images, whose processing is provided through the library GDAL. To install it, run the following commands:

sudo apt install libgdal-dev
pip3 install gdal[numpy]=="$(gdal-config --version).*"

To enable the Mitsuba road optimization option, enable it in the OpenDriveToMap blueprint:

Alternatively, set the bUseMitsuba flag to true in OpenDriveToMap.h (line 187):

bool bUseMitsuba = true;

and compile the project.

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Windows Build Instructions

1. Right-click the .uproject file and select "Generate Visual Studio project files".
2. Open the generated .sln file with Visual Studio 2022 or any compatible version for UE5.
3. Build the solution using Development Editor configuration and Win64 platform.
4. Once compiled, run the project from Visual Studio (F5) or by double-clicking the .uproject file.

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How to Use the CARLA Digital Twins Tool in Unreal Engine

Prerequisite

Make sure the Digital Twins plugin is correctly installed and built in your Unreal Engine 5 project, as described in the build instructions.

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Steps to Launch the Digital Twins Tool

1. Open your Unreal Engine project where the Digital Twins plugin is installed.

2. In the Content Browser, go to the bottom-right corner and click the eye icon to enable "Show Plugin Content".

   

3. On the left panel, a new section will appear labeled DigitalTwins Content. Expand it.

   

4. Inside that folder, locate the file named:
   UW_DigitalTwins

5. Right-click on UW_DigitalTwins and select:

   Run Editor Utility Widget
   

   

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Importing a Real Map from OpenStreetMap

6. Once the tool launches, a UI will appear with three sections:

   • Filename – your custom name for the map
   • OSM URL – the URL from OpenStreetMap
   • LocalFilePath – optional local saving path

7. Go to https://www.openstreetmap.org.

8. Search and zoom into the area you want to replicate.

9. Click the Export button on the top menu, the one in the upper part of the window which is between other buttons as shown in the following screenshot:

10. On the left side of the window screen, find the text: “Overpass API”
    Right-click the link and select “Copy link address”.

    

11. Go back to the Digital Twins tool in Unreal:

    • Paste the copied URL into the OSMURL field.
    • Enter a desired name into the Filename field.

12. Click the Generate button.

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Generation and Preview

13. Unreal Engine might seem frozen — don't worry, it's processing the data.

    • You can check the progress in the Output Log.

14. Once the generation is complete, click Play to explore your generated digital twin of the map inside the Unreal environment.

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Importing the Generated Map into Another Unreal Project

Once the map generation process is complete:

1. Close the Unreal Editor.

2. Open your file explorer and navigate to the Plugins folder of the project where you originally generated the map.

3. Inside the Plugins folder, you will see a plugin folder named after the map name you entered in the Digital Twins UI.

4. Copy that folder.

5. Go to the target Unreal project (the one where you want to use the map) and paste the copied folder into its own Plugins directory.

6. Launch the target project. Unreal Engine will detect the plugin automatically and compile it if necessary.

Note: Make sure the target project is also using the same Unreal Engine version and build to avoid compatibility issues.