Add support for Linux (on 64-bit Intel/AMD)

.github/workflows/build.yml

@@ -340,6 +340,118 @@ jobs:
           name: Tests - macOS
           path: /Users/runner/cesium/CesiumForUnityBuildProject/TestResults.xml
           reporter: dotnet-nunit
+  Linux:
+    needs: [QuickChecks]
+    runs-on: ubuntu-latest
+    # Only allow a single Linux build at a time, for Unity licensing reasons
+    concurrency: linux
+    steps:
+      - name: Check out repository code
+        uses: actions/checkout@v4
+        with:
+          submodules: recursive
+      - name: Set up .NET SDK
+        uses: actions/setup-dotnet@v4
+        with:
+          dotnet-version: "10.0.103"
+      - name: Cache vcpkg artifacts
+        uses: actions/cache@v4
+        with:
+          path: "~/.ezvcpkg"
+          key: vcpkg-linux-alma-${{ hashFiles('native~/vcpkg/ports/**/vcpkg.json', 'native~/vcpkg/triplets/**/*', 'native~/extern/*toolchain.cmake') }}-${{ hashFiles('native~/extern/cesium-native/CMakeLists.txt', 'native~/CMakeLists.txt') }}
+          restore-keys: |
+            vcpkg-linux-alma-${{ hashFiles('native~/vcpkg/ports/**/vcpkg.json', 'native~/vcpkg/triplets/**/*', 'native~/extern/*toolchain.cmake') }}-
+      - name: Install Unity Hub
+        run: |
+          sudo apt-get install -y gnupg libgbm1 xvfb
+          wget -qO - https://hub.unity3d.com/linux/keys/public | gpg --dearmor | sudo tee /usr/share/keyrings/Unity_Technologies_ApS.gpg > /dev/null
+          sudo sh -c 'echo "deb [signed-by=/usr/share/keyrings/Unity_Technologies_ApS.gpg] https://hub.unity3d.com/linux/repos/deb stable main" > /etc/apt/sources.list.d/unityhub.list'
+          sudo apt-get update
+          sudo apt-get install -y unityhub
+      - name: Install Unity 2022.3.41f1
+        # This command sometimes returns exit code 130, despite actually succeeding.
+        # unityhub-bin requires a virtual display even in headless mode.
+        continue-on-error: true
+        run: |
+          xvfb-run -a /opt/unityhub/unityhub-bin --no-sandbox --headless install --version 2022.3.41f1 --changeset 0f988161febf
+      - name: Configure Unity to Use the License Server
+        run: |
+          sudo mkdir -p /usr/share/unity3d/config
+          sudo bash -c 'echo "{\"licensingServiceBaseUrl\": \"http://localhost:12331\",\"enableEntitlementLicensing\": true,\"clientConnectTimeoutSec\": 60,\"clientHandshakeTimeoutSec\": 120,\"toolset\":\"UnityLicenseServer_16768262570522_9\"}" > /usr/share/unity3d/config/services-config.json'
+      - name: Create SSH tunnel to Unity License Server
+        env:
+          UNITY_LICENSE_SERVER_SSH_KEY: ${{ secrets.UNITY_LICENSE_SERVER_SSH_KEY }}
+        run: |
+          echo "$UNITY_LICENSE_SERVER_SSH_KEY" > ~/unity-client-ssh-key
+          chmod 600 ~/unity-client-ssh-key
+          # Without StrictHostKeyChecking, OpenSSH will sit forever waiting for local input to confirm the server key is ok.
+          # We don't really care if the server is authentic, because we're not sending anything sensitive to it.
+          # The license server VM's sshd_config also needed to be modified with the following options, in order to prevent
+          # the tunnel from being closed between here and when we're ready to use it.
+          #   TCPKeepAlive yes
+          #   ClientAliveInterval 30
+          #   ClientAliveCountMax 9999
+          ssh -fNT -o StrictHostKeyChecking=no -i ~/unity-client-ssh-key -L 127.0.0.1:12331:127.0.0.1:8080 unity-client@ec2-44-204-244-196.compute-1.amazonaws.com
+          sleep 5
+      - name: Test Connection to Unity License Server
+        run: |
+          wget http://127.0.0.1:12331/v1/admin/status
+          cat status
+          rm status
+      - name: Update the version in Cesium.cpp
+        run: |
+          export VERSION=$(jq -r ".version" package.json)
+          export COMMIT=$(git rev-parse --short HEAD)
+          sed -i 's/Cesium::version = "Development Build"/Cesium::version = "'$VERSION'"/g' native~/src/Runtime/Cesium.cpp
+          sed -i 's/Cesium::commit = "Unknown"/Cesium::commit = "'$COMMIT'"/g' native~/src/Runtime/Cesium.cpp
+          # Sanity check that the replacements happened
+          grep $VERSION native~/src/Runtime/Cesium.cpp
+          grep $COMMIT native~/src/Runtime/Cesium.cpp
+      - name: Move cesium-unity Repo Under Empty Project
+        run: |
+          mkdir -p ~/cesium/CesiumForUnityBuildProject/Packages/com.cesium.unity
+          mv $GITHUB_WORKSPACE/* ~/cesium/CesiumForUnityBuildProject/Packages/com.cesium.unity
+          # Disable Unity audio
+          mkdir -p ~/cesium/CesiumForUnityBuildProject/Packages/com.cesium.unity/ProjectSettings
+          echo '%YAML 1.1\n%TAG !u! tag:unity3d.com,2011:\n--- !u!11 &1\nAudioManager:\n  m_DisableAudio: 1\n' > ~/cesium/CesiumForUnityBuildProject/Packages/com.cesium.unity/ProjectSettings/AudioManager.asset
+      - name: Build Reinterop
+        run: |
+          cd ~/cesium/CesiumForUnityBuildProject/Packages/com.cesium.unity
+          dotnet publish Reinterop~ -o .
+      - name: Build Package
+        env:
+          CESIUM_NATIVE_BUILD_CONTAINER: almalinux:8
+        run: |
+          # We only need a release build of vcpkg dependencies
+          export CESIUM_VCPKG_RELEASE_ONLY="TRUE"
+          cd ~/cesium/CesiumForUnityBuildProject/Packages/com.cesium.unity
+          dotnet run --project Build~ package --platform Editor --platform Linux
+          ls -l ~/cesium/CesiumForUnityBuildProject
+      - name: Publish Logs
+        if: success() || failure()    # run this step even if previous step failed
+        uses: actions/upload-artifact@v4
+        with:
+          name: Native Build Logs - Linux
+          path: ~/cesium/CesiumForUnityBuildProject/Packages/com.cesium.unity/native~/build-*/build.log
+      - name: Publish package artifact
+        if: ${{ success() }}
+        uses: actions/upload-artifact@v4
+        with:
+          name: Linux Package
+          path: ~/cesium/CesiumForUnityBuildProject/*.tgz
+      - name: Run Tests
+        env:
+          CESIUM_ION_TOKEN_FOR_TESTS: ${{ secrets.CESIUM_ION_TOKEN_FOR_TESTS }}
+        run: |
+          xvfb-run -a ~/Unity/Hub/Editor/2022.3.41f1/Editor/Unity -runTests -batchmode -projectPath ~/cesium/CesiumForUnityBuildProject -testResults ~/cesium/CesiumForUnityBuildProject/TestResults.xml -testPlatform PlayMode -logFile ~/cesium/CesiumForUnityBuildProject/test-log.txt
+          cat ~/cesium/CesiumForUnityBuildProject/test-log.txt
+      - name: Test Report
+        uses: kring/test-reporter@v1.6.2-kring
+        if: success() || failure()    # run this step even if previous step failed
+        with:
+          name: Tests - Linux
+          path: /home/runner/cesium/CesiumForUnityBuildProject/TestResults.xml
+          reporter: dotnet-nunit
   Emscripten:
     needs: [QuickChecks]
     runs-on: windows-latest
@@ -466,7 +578,7 @@ jobs:
           path: d:\cesium\CesiumForUnityBuildProject\*.tgz
   Combine:
     runs-on: ubuntu-latest
-    needs: [Windows, MacOS, Emscripten]
+    needs: [Windows, MacOS, Linux, Emscripten]
     steps:
       - name: Check out repository code
         uses: actions/checkout@v4
@@ -492,6 +604,16 @@ jobs:
           cd combine/emscripten
           tar xzf *.tgz
           rm *.tgz
+      - name: Download Linux build
+        uses: actions/download-artifact@v4
+        with:
+          name: Linux Package
+          path: combine/linux
+      - name: Extract Linux build
+        run: |
+          cd combine/linux
+          tar xzf *.tgz
+          rm *.tgz
       - name: Download Windows build
         uses: actions/download-artifact@v4
         with:
@@ -510,6 +632,7 @@ jobs:
           # Copy the everything. For files that exist in multiple packages, the Windows one will win.
           cp -r ../macos/* .
           cp -r ../emscripten/* .
+          cp -r ../linux/* .
           cp -r ../windows/* .
 
           # Remove the generated C# files
@@ -534,6 +657,14 @@ jobs:
             cat "$file" >> "../merged/$file"
           done;
 
+          cd ../linux
+          for file in $(find package/Source/generated -name '*.cs');
+          do
+            echo Merging $file
+            mkdir -p $(dirname "../merged/$file")
+            cat "$file" >> "../merged/$file"
+          done;
+
           cd ../windows
           for file in $(find package/Source/generated -name '*.cs');
           do

Build~/Package.cs

@@ -181,8 +181,14 @@ public void Run(Options options)
                     else
                     {
                         // On other platforms, just build once.
-                        Utility.Run("cmake", configureArgs);
-                        Utility.Run("cmake", buildArgs);
+                        string? containerImage = Environment.GetEnvironmentVariable("CESIUM_NATIVE_BUILD_CONTAINER");
+                        if (OperatingSystem.IsLinux() && !string.IsNullOrEmpty(containerImage))
+                            RunCmakeInContainer(containerImage, configureArgs, buildArgs);
+                        else
+                        {
+                            Utility.Run("cmake", configureArgs);
+                            Utility.Run("cmake", buildArgs);
+                        }
                     }
                 }
 
@@ -279,6 +285,29 @@ public void Run(Options options)
                     Directory.CreateDirectory(generatedPath);
                 }
 
+                if (options.Platforms.Contains("Linux"))
+                {
+                    Console.WriteLine("**** Compiling for Linux Player");
+                    unity.Run(new[]
+                    {
+                        "-batchmode",
+                        "-nographics",
+                        "-projectPath",
+                        Utility.ProjectRoot,
+                        "-buildTarget",
+                        "Linux64",
+                        "-executeMethod",
+                        "CesiumForUnity.BuildCesiumForUnity.CompileForLinuxAndExit"
+                    });
+
+                    Console.WriteLine("**** Adding generated files (for the Linux Player) to the package");
+                    AddGeneratedFiles("!UNITY_EDITOR && UNITY_STANDALONE_LINUX", generatedPath, outputGeneratedPath);
+
+                    // Clean the generated code directory.
+                    Directory.Delete(generatedPath, true);
+                    Directory.CreateDirectory(generatedPath);
+                }
+
                 if (options.Platforms.Contains("macOS"))
                 {
                     Console.WriteLine("**** Compiling for macOS Player");
@@ -368,6 +397,74 @@ private static void TraverseDirectoryRecursively(string directory, string builtP
             }
         }
 
+        private static void RunCmakeInContainer(
+            string containerImage,
+            IEnumerable<string> configureArgs,
+            IEnumerable<string> buildArgs)
+        {
+            string packageRoot = Utility.PackageRoot;
+            string ezvcpkgHostPath = Path.Combine(
+                Environment.GetFolderPath(Environment.SpecialFolder.UserProfile), ".ezvcpkg");
+
+            // Write cmake commands to a script file to avoid shell quoting complexity.
+            string scriptPath = Path.Combine(Path.GetTempPath(), $"cesium-cmake-{Guid.NewGuid():N}.sh");
+            File.WriteAllText(scriptPath,
+                "#!/bin/bash\n" +
+                "set -e\n" +
+                "dnf install -q -y dnf-plugins-core\n" +
+                "dnf config-manager --set-enabled powertools\n" +
+                "dnf module enable -y llvm-toolset\n" +
+                "dnf install -q -y clang make nasm git curl zip unzip tar kernel-headers perl-core ninja-build python3 pkgconfig autoconf automake libtool patch\n" +
+                "curl -fsSL https://github.com/Kitware/CMake/releases/download/v3.31.12/cmake-3.31.12-linux-x86_64.tar.gz | tar -xz -C /usr/local --strip-components=1\n" +
+                "curl -fsSL https://awscli.amazonaws.com/awscli-exe-linux-x86_64.zip -o /tmp/awscliv2.zip && unzip -q /tmp/awscliv2.zip -d /tmp && /tmp/aws/install && rm -rf /tmp/awscliv2.zip /tmp/aws\n" +
+                $"cmake {string.Join(' ', configureArgs)}\n" +
+                $"cmake {string.Join(' ', buildArgs)}\n",
+                new UTF8Encoding(false));
+
+            try
+            {
+                ProcessStartInfo dockerInfo = new ProcessStartInfo("docker");
+                dockerInfo.WorkingDirectory = packageRoot;
+
+                dockerInfo.ArgumentList.Add("run");
+                dockerInfo.ArgumentList.Add("--rm");
+                dockerInfo.ArgumentList.Add("--workdir");
+                dockerInfo.ArgumentList.Add(packageRoot);
+                dockerInfo.ArgumentList.Add("-v");
+                dockerInfo.ArgumentList.Add($"{packageRoot}:{packageRoot}");
+                dockerInfo.ArgumentList.Add("-v");
+                dockerInfo.ArgumentList.Add($"{ezvcpkgHostPath}:/root/.ezvcpkg");
+                dockerInfo.ArgumentList.Add("-v");
+                dockerInfo.ArgumentList.Add($"{scriptPath}:/tmp/cesium-build.sh:ro");
+                dockerInfo.ArgumentList.Add("-e");
+                dockerInfo.ArgumentList.Add("CC=clang");
+                dockerInfo.ArgumentList.Add("-e");
+                dockerInfo.ArgumentList.Add("CXX=clang++");
+
+                foreach (string envVarName in new[] {
+                    "VCPKG_BINARY_SOURCES", "AWS_ACCESS_KEY_ID", "AWS_SECRET_ACCESS_KEY",
+                    "AWS_REGION", "CESIUM_VCPKG_RELEASE_ONLY" })
+                {
+                    string? value = Environment.GetEnvironmentVariable(envVarName);
+                    if (!string.IsNullOrEmpty(value))
+                    {
+                        dockerInfo.ArgumentList.Add("-e");
+                        dockerInfo.ArgumentList.Add($"{envVarName}={value}");
+                    }
+                }
+
+                dockerInfo.ArgumentList.Add(containerImage);
+                dockerInfo.ArgumentList.Add("bash");
+                dockerInfo.ArgumentList.Add("/tmp/cesium-build.sh");
+
+                Utility.RunAndLog(dockerInfo);
+            }
+            finally
+            {
+                try { File.Delete(scriptPath); } catch (Exception) { }
+            }
+        }
+
         private static void AddGeneratedFiles(string condition, string source, string target)
         {
             TraverseDirectoryRecursively(

Build~/Unity.cs

@@ -133,6 +133,11 @@ private class UnityVersion
                 unityDefaultBaseDirectory = new DirectoryInfo("/Applications/Unity/Hub/Editor");
                 unityExecutableSubPath = "Unity.app/Contents/MacOS/Unity";
             }
+            else if (OperatingSystem.IsLinux())
+            {
+                unityDefaultBaseDirectory = new DirectoryInfo(Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.UserProfile), "Unity", "Hub", "Editor"));
+                unityExecutableSubPath = "Editor/Unity";
+            }
             else
             {
                 return null;
@@ -141,6 +146,9 @@ private class UnityVersion
             if (unityDir == null)
                 unityDir = unityDefaultBaseDirectory;
 
+            if (!unityDir.Exists)
+                return null;
+
             if (version != null)
             {
                 FileInfo unityExecutable = new FileInfo(Path.Combine(unityDir.FullName, version, unityExecutableSubPath));

CHANGES.md

@@ -1,5 +1,11 @@
 # Change Log {#changes}
 
+## ? - ?
+
+##### Additions :tada:
+
+- Added support for the Linux platform (x86-64 only).
+
 ## v1.23.1 - 2026-04-01
 
 This release updates [cesium-native](https://github.com/CesiumGS/cesium-native) from v0.58.0 to v0.59.0. See the [changelog](https://github.com/CesiumGS/cesium-native/blob/main/CHANGES.md) for a complete list of changes in cesium-native.

EditorTests/CesiumEditorTests.asmdef

@@ -18,8 +18,7 @@
     ],
     "autoReferenced": false,
     "defineConstraints": [
-        "UNITY_INCLUDE_TESTS",
-        "!UNITY_EDITOR_LINUX"
+        "UNITY_INCLUDE_TESTS"
     ],
     "versionDefines": [],
     "noEngineReferences": false

Source/CesiumForUnity.asmdef

@@ -10,6 +10,7 @@
         "Android",
         "Editor",
         "iOS",
+        "LinuxStandalone64",
         "macOSStandalone",
         "WSA",
         "WindowsStandalone64",
@@ -20,9 +21,7 @@
     "overrideReferences": false,
     "precompiledReferences": [],
     "autoReferenced": true,
-    "defineConstraints": [
-        "!UNITY_EDITOR_LINUX"
-    ],
+    "defineConstraints": [],
     "versionDefines": [
         {
             "name": "com.unity.splines",

Source/Editor/BuildCesiumForUnity.cs

@@ -126,6 +126,23 @@ public static void CompileForWindowsAndExit()
             EditorApplication.Exit(0);
         }
 
+        public static void CompileForLinuxAndExit()
+        {
+            CompileCesiumForUnityNative.ExitAfterCompile = true;
+
+            string buildPath = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString());
+            Directory.CreateDirectory(buildPath);
+            try
+            {
+                BuildPlayer(BuildTargetGroup.Standalone, BuildTarget.StandaloneLinux64, Path.Combine(buildPath, "Linux"));
+            }
+            finally
+            {
+                Directory.Delete(buildPath, true);
+            }
+            EditorApplication.Exit(0);
+        }
+
         public static void CompileForMacAndExit()
         {
             CompileCesiumForUnityNative.ExitAfterCompile = true;