Integrate Amazon GameLift into an Unreal Engine project

To clone the Unreal Engine source to your development environment

1. Clone the Unreal Engine source to your development environment in a branch of your choice.

   git clone https://github.com/EpicGames/UnrealEngine.git

2. Check out the tag of the version that you're using to develop your game. For example, the following example checks out Unreal Engine version 5.1.1:

   git checkout tags/5.1.1-release -b 5.1.1-release

3. Navigate to the root folder of the local repository. When you're in the root folder, run the following file: Setup.bat.

4. While in the root folder, also run the file: GenerateProjectFiles.bat.

5. After running the files from the previous steps, an Unreal Engine solution file, UE5.sln, is created. Open Visual Studio, and in the Visual Studio editor open the UE5.sln file.

6. In Visual Studio, open the View menu and choose the Solution Explorer option. This opens the context menu of the Unreal project node. In the Solution Explorer window, right-click the UE5.sln file (it can be listed as just UE5), then choose Build to build the Unreal project with the Development Editor Win64 target.

   Note

   The build can take over an hour to complete.

To configure your project for the plugin

1. With Visual Studio open, navigate to the Solution Explorer pane and choose the UE5 file to open the context menu for the Unreal project. In the context menu, choose the Set as Startup Project option.

2. At the top of your Visual Studio window, choose Start Debugging (green arrow).

   This action starts your new source-built instance of Unreal Editor. For more information about using the Unreal Editor, see Unreal Editor Interface on the Unreal Engine documentation website.

3. Close the Visual Studio window you opened, since the Unreal Editor opens a another Visual Studio window that contains the Unreal project and your game project.

4. In the Unreal editor, do one of the following:

   • Choose an existing Unreal project that you want to integrate with Amazon GameLift.

   • Create a new project. To experiment with the Amazon GameLift plugin for Unreal, try using Unreal engine's Third Person template. For more information about this template, see Third Person template on the Unreal Engine documentation website.

     Alternatively, configure a new project with the following settings:

     • C++

     • With starter content

     • Desktop

     • A project name. In the examples in this topic, we named our project GameLiftUnrealApp.

5. In Visual Studio's Solution Explorer, navigate to the location of your Unreal project. In the Unreal Source folder, find a file named Your-application-name.Target.cs.

   For example: GameLiftUnrealApp.Target.cs.

6. Make a copy of this file and name the copy: Your-application-nameServer.Target.cs.

7. Open the new file and make the following changes:

   • Change the class and constructor to match the filename.

   • Change the Type from TargetType.Game to TargetType.Server.

   • The final file will look like the following example:

        public class GameLiftUnrealAppServerTarget : TargetRules
         {  
             public GameLiftUnrealAppServerTarget(TargetInfo Target) : base(Target)
             {
                 Type = TargetType.Server;
                 DefaultBuildSettings = BuildSettingsVersion.V2;
                 IncludeOrderVersion = EngineIncludeOrderVersion.Unreal5_1;
                 ExtraModuleNames.Add("GameLiftUnrealApp");
             }
         }

To build the C++ server SDK libraries for Unreal

1. Download the Amazon GameLift C++ server SDK plugin for Unreal.

   Note

   Putting the SDK in the default download directory can result in build failure due to the path exceeding the 260 character limit. For example: C:\Users\Administrator\Downloads\GameLift-SDK-Release-06_15_2023\GameLift-Cpp-ServerSDK-5.0.4

   We recommend that you move the SDK to another directory, for example C:\GameLift-Cpp-ServerSDK-5.0.4.

2. Download and install OpenSSL. For more information on downloading OpenSSL, read the Github OpenSSL build and install documentation.

   For more information, read the OpenSSL Notes for Windows platforms documentation.

   Note

   The version of OpenSSL that you use to build the Amazon GameLift server SDK should match the version of OpenSSL used by Unreal to package your game server. You can find version information in the Unreal installation directory ...Engine\Source\ThirdParty\OpenSSL.

3. With the libraries downloaded, build the C++ server SDK libraries for Unreal Engine.

   In the GameLift-Cpp-ServerSDK-<version> directory in the downloaded SDK, compile with the -DBUILD_FOR_UNREAL=1 parameter and build the server SDK. The following examples show how to compile using cmake.

   Run the following commands in your terminal:

   mkdir cmake-build
   cmake.exe -G "Visual Studio 17 2022" -DCMAKE_BUILD_TYPE=Release -S . -B ./cmake-build -DBUILD_FOR_UNREAL=1 -A x64
   cmake.exe --build ./cmake-build --target ALL_BUILD --config Release

   The Windows build creates the following binary files in the out\gamelift-server-sdk\Release folder:

   • cmake-build\prefix\bin\aws-cpp-sdk-gamelift-server.dll

   • cmake-build\prefix\bin\aws-cpp-sdk-gamelift-server.lib

   Copy the two library files to the ThirdParty\GameLiftServerSDK\Win64 folder in the Amazon GameLift Unreal Engine plugin package.

Import the Amazon GameLift plugin

1. Locate the GameLiftServerSDK folder that you extracted from the plugin in the earlier procedure.

2. Locate the Plugins in your game project root folder. (If the folder does not exist, then create it there.)

3. Copy the GameLiftServerSDK folder into the Plugins.

   This will allow the Unreal project to see the plugin.

4. Add the Amazon GameLift server SDK plugin to the game's .uproject file.

   In the example, the app is called GameLiftUnrealApp, so the file will be GameLiftUnrealApp.uproject.

5. Edit the .uproject file to add the plugin to your game project.

   "Plugins": [
       {
           "Name": "GameLiftServerSDK",
           "Enabled": true
       }
   ]

6. Make sure the game's ModuleRules takes a dependency on the plugin. Open the .Build.cs file and add the Amazon GameLiftServerSDK dependency. This file is found under Your-application-name/Source//Your-application-name/.

   For example, the tutorial filepath is ../GameLiftUnrealApp/Source/GameLiftUnrealApp/GameLiftUnrealApp.Build.cs.

7. Add "GameLiftServerSDK" to the end of the list of PublicDependencyModuleNames.

   using UnrealBuildTool;
   using System.Collections.Generic;
   public class GameLiftUnrealApp : ModuleRules  
     {
       public GameLiftUnrealApp(TargetInfo Target)
       {
         PublicDependencyModuleNames.AddRange(new string[] { "Core", "CoreUObject", "Engine", "InputCore", "GameLiftServerSDK" });
         bEnableExceptions = true;
       }
     }

To build your game server

When you've finished adding server SDK code to your project, take the following steps to create a game server build and upload it to Amazon GameLift for hosting.

1. Build game project for both of the following target types: Development Editor and Development Server.

   Note

   You don't need to rebuild the solution. Instead, build just the project under the Games folder that matches the name of your app. Otherwise Visual Studio rebuilds the entire UE5 project, which might take up to an hour.

2. When both builds are complete, close Visual Studio and open your project's .uproject file to open it in the Unreal Editor.

3. In Unreal Editor, package the server build of your game. To choose a target, go to Platforms, Windows and select Your-application-nameServer.

4. To start the process of building the server application, go to Platforms, Windows and select Package Project. When the build is complete, you have an executable, such as GameLiftUnrealAppServer.exe.

5. Building a server application in Unreal Editor produces two executables. One is located in the root of the game build folder and acts as a wrapper for the actual server executable.

   When creating an Amazon GameLift fleet with your server build, we recommend that you pass in the actual server executable as the runtime configuration launch path. For example, in your game build folder, you might have a GameLiftFPS.exe file at the root and another at \GameLiftFPS\Binaries\Win64\GameLiftFPSServer.exe. When creating a fleet, we recommend you use C:\GameLiftFPS\Binaries\Win64\GameLiftFPSServer.exe as the launch path of the runtime configuration.

6. Make sure to open the necessary UDP ports on the Amazon GameLift fleet, so that the game server can communicate with game clients. By default, Unreal Engine uses port 7777. For more information, see UpdateFleetPortSettings in the Amazon GameLift service API reference guide.

7. Create an install.bat file for your game build. This install script runs whenever the game build is deployed to a Amazon GameLift fleet. Here's an example install.bat file:

   VC_redist.x64.exe /q
   UE5PrereqSetup_x64.exe /q

8. Now you can package and upload your game build to Amazon GameLift.

   The version of OpenSSL you use for your build needs to match the version used by the game server. Make sure you package the correct OpenSSL version with your game server build. For the Windows OS, the OpenSSL format is .dll.

   Note

   Package the OpenSSL DLLS in your game server build. Be sure to use the DLLs for the same version as you used when you build the game server.

   • libssl-3-x64.dll

   • libcrypto-3-x64.dll

   Package your dependencies along with your game server executable in in the root of a zip file. For example, openssl-lib dlls should be in the same directory as the .exe file.