Add Android host support (arm64, GDI, Vulkan)

.github/workflows/build.yml

@@ -62,10 +62,70 @@ jobs:
           path: artifacts/packages/*
           retention-days: 14
 
+  android:
+    name: Build Android arm64
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v6
+
+      # A .NET 9 SDK is required even though the project targets net8.0: the source generator needs
+      # Roslyn >= 4.10.
+      - name: Setup .NET
+        uses: actions/setup-dotnet@v5
+        with:
+          dotnet-version: 9.0.x
+
+      - name: Setup JDK
+        uses: actions/setup-java@v5
+        with:
+          distribution: temurin
+          java-version: '17'
+
+      - name: Setup Gradle
+        uses: gradle/actions/setup-gradle@v4
+        with:
+          gradle-version: '8.7'
+
+      # The NDK version has to match ndkVersion in Brovan/Android/app/brovan/build.gradle; the runner image
+      # preinstalls a newer one that build-apk.sh would otherwise pick.
+      - name: Install the Android NDK and CMake
+        run: |
+          SDKMANAGER="$ANDROID_SDK_ROOT/cmdline-tools/latest/bin/sdkmanager"
+          yes | "$SDKMANAGER" --licenses > /dev/null 2>&1 || true
+          "$SDKMANAGER" "ndk;26.3.11579264" "cmake;3.22.1" "platforms;android-34" "build-tools;34.0.0"
+          echo "ANDROID_NDK_HOME=$ANDROID_SDK_ROOT/ndk/26.3.11579264" >> "$GITHUB_ENV"
+
+      - name: Cache OpenSSL
+        uses: actions/cache@v4
+        with:
+          path: ~/brovan-toolchain/openssl-3.5.4
+          key: brovan-openssl-3.5.4-android-arm64
+
+      - name: Build OpenSSL for android-arm64
+        run: bash Brovan/Android/build-openssl.sh
+
+      - name: Cache Unicorn
+        uses: actions/cache@v4
+        with:
+          path: Brovan/.cache/unicorn
+          key: brovan-unicorn-android-arm64-${{ hashFiles('Brovan/Brovan.Unicorn.targets') }}
+
+      - name: Build APK
+        run: bash Brovan/Android/build-apk.sh
+
+      - name: Upload CI Artifact
+        uses: actions/upload-artifact@v6
+        with:
+          name: Brovan Android arm64
+          path: artifacts/android/*.apk
+          retention-days: 14
+
   release:
     name: Publish GitHub Release
     if: startsWith(github.ref, 'refs/tags/')
-    needs: build
+    needs: [ build, android ]
     runs-on: ubuntu-latest
     permissions:
       contents: write
@@ -80,6 +140,6 @@ jobs:
         env:
           GH_TOKEN: ${{ github.token }}
         run: |
-          gh release create "${{ github.ref_name }}" release-artifacts/**/*
-            --title "${{ github.ref_name }}"
+          gh release create "${{ github.ref_name }}" release-artifacts/**/* \
+            --title "${{ github.ref_name }}" \
             --generate-notes

.gitignore

@@ -62,3 +62,8 @@ nunit-*.xml
 /Brovan.Graphics/brovvulk-icd/generated
 /VirtualFS
 /Brovan/Properties
+/Brovan/Android/app/.gradle/
+/Brovan/Android/app/**/build/
+/Brovan/Android/app/local.properties
+/Brovan/Android/app/brovan/src/main/jniLibs/
+/*.apk

Brovan.Android/Brovan.Android.csproj

@@ -0,0 +1,34 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <!--
+    Solution entry point for the APK. Nothing is compiled here: Brovan/Android/build-apk.sh publishes the
+    emulator for linux-bionic-arm64, cross-builds Unicorn and runs gradle. The script only works on a Linux
+    host (NativeAOT does not cross-compile from Windows to linux-bionic), so a Windows build is a no-op.
+  -->
+
+  <PropertyGroup>
+    <TargetFramework>net8.0</TargetFramework>
+    <EnableDefaultItems>false</EnableDefaultItems>
+    <BuildAndroidApk Condition="'$(BuildAndroidApk)' == '' and $([MSBuild]::IsOSPlatform('Windows'))">false</BuildAndroidApk>
+    <BuildAndroidApk Condition="'$(BuildAndroidApk)' == ''">true</BuildAndroidApk>
+    <AndroidBuildScript>$([MSBuild]::NormalizePath($(MSBuildThisFileDirectory), '..', 'Brovan', 'Android', 'build-apk.sh'))</AndroidBuildScript>
+    <AndroidApkOutput>$([MSBuild]::NormalizePath($(MSBuildThisFileDirectory), '..', 'artifacts', 'android', 'brovan-arm64-v8a.apk'))</AndroidApkOutput>
+  </PropertyGroup>
+
+  <Target Name="ReportSkippedAndroidApk" AfterTargets="Build" Condition="'$(BuildAndroidApk)' != 'true'">
+    <Message Importance="normal" Text="[Brovan.Android] APK skipped on this host; build on Linux or pass -p:BuildAndroidApk=true." />
+  </Target>
+
+  <Target Name="BuildAndroidApk" AfterTargets="Build" Condition="'$(BuildAndroidApk)' == 'true'">
+    <Message Importance="high" Text="[Brovan.Android] Building the APK ($(Configuration))..." />
+    <Exec Command="bash &quot;$(AndroidBuildScript)&quot;" IgnoreExitCode="true"
+          EnvironmentVariables="CONFIG=$(Configuration);BROVAN_APK_OUTPUT=$(AndroidApkOutput)">
+      <Output TaskParameter="ExitCode" PropertyName="_AndroidApkExitCode" />
+    </Exec>
+    <!-- 3 is build-apk.sh's "no Android toolchain here"; a desktop Linux checkout should still build. -->
+    <Warning Condition="'$(_AndroidApkExitCode)' == '3'" Text="[Brovan.Android] APK skipped: no Android toolchain on this host (see Brovan/Android/README.md)." />
+    <Error Condition="'$(_AndroidApkExitCode)' != '0' and '$(_AndroidApkExitCode)' != '3'" Text="[Brovan.Android] build-apk.sh failed with exit code $(_AndroidApkExitCode)." />
+    <Message Condition="'$(_AndroidApkExitCode)' == '0'" Importance="high" Text="[Brovan.Android] APK -> $(AndroidApkOutput)" />
+  </Target>
+
+</Project>

Brovan.Generators/VulkanForwardGenerator.cs

@@ -1078,7 +1078,7 @@ private static string EmitHostCase(Model m, Command c, int id)
                     "                uint hasCi = r.ReadU32();\n" +
                     "                System.IntPtr ci = System.IntPtr.Zero;\n" +
                     "                if (hasCi != 0) ci = BrovVulkGenStruct.Rebuild(" + StructId["VkInstanceCreateInfo"] + ", r, st);\n" +
-                    "                if (Brovan.GeneralHelper.IsLinux && ci != System.IntPtr.Zero)\n" +
+                    "                if ((Brovan.GeneralHelper.IsLinux || Brovan.Android.AndroidHost.IsActive) && ci != System.IntPtr.Zero)\n" +
                     "                {\n" +
                     "                    System.IntPtr extPtr = *(System.IntPtr*)(ci + 56);\n" +
                     "                    uint extCount = *(uint*)(ci + 48);\n" +
@@ -1100,7 +1100,7 @@ private static string EmitHostCase(Model m, Command c, int id)
                     "                        }\n" +
                     "                        if (sawWin32)\n" +
                     "                        {\n" +
-                    "                            System.IntPtr xcbName = System.Runtime.InteropServices.Marshal.StringToHGlobalAnsi(\"VK_KHR_xcb_surface\");\n" +
+                    "                            System.IntPtr xcbName = System.Runtime.InteropServices.Marshal.StringToHGlobalAnsi(Brovan.Android.AndroidHost.IsActive ? \"VK_KHR_android_surface\" : \"VK_KHR_xcb_surface\");\n" +
                     "                            System.Runtime.InteropServices.Marshal.WriteIntPtr(newArr, (int)(newCount * 8), xcbName);\n" +
                     "                            newCount++;\n" +
                     "                            *(uint*)(ci + 48) = newCount;\n" +
@@ -1118,7 +1118,16 @@ private static string EmitHostCase(Model m, Command c, int id)
                     "                System.IntPtr vi = st.Lookup(r.ReadU32(), \"VkInstance\");\n" +
                     "                System.IntPtr surf = System.IntPtr.Zero;\n" +
                     "                int rr;\n" +
-                    "                if (Brovan.GeneralHelper.IsLinux)\n" +
+                    "                if (Brovan.Android.AndroidHost.IsActive)\n" +
+                    "                {\n" +
+                    "                    System.IntPtr awin = inst.WinHelper.EnsureHostWindowHandle();\n" +
+                    "                    byte* ci = stackalloc byte[32];\n" +
+                    "                    for (int z = 0; z < 32; z++) ci[z] = 0;\n" +
+                    "                    *(int*)(ci + 0) = " + "1000008000" + ";\n" +
+                    "                    *(void**)(ci + 24) = (void*)awin;\n" +
+                    "                    rr = (int)Brovan.Android.AndroidVulkanWsi.vkCreateAndroidSurfaceKHR(vi, (System.IntPtr)ci, System.IntPtr.Zero, (System.IntPtr)(&surf));\n" +
+                    "                }\n" +
+                    "                else if (Brovan.GeneralHelper.IsLinux)\n" +
                     "                {\n" +
                     "                    System.IntPtr xdpy; System.IntPtr xwin;\n" +
                     "                    inst.WinHelper.EnsureHostXlibSurfaceHandles(out xdpy, out xwin);\n" +