CI: build and publish Linux ARM64 native (test run, do not merge)

.github/workflows/ci.yml

@@ -55,6 +55,8 @@ jobs:
         target:
           - os: ubuntu-latest
             type: linux
+          - os: ubuntu-24.04-arm
+            type: linuxarm64
           - os: ubuntu-latest
             type: windows
           - os: macos-latest

bin/README.md

@@ -25,11 +25,13 @@ The expected library file names for different operating systems are:
 |---------|-----------------------|
 | Windows | imgui-java64.dll      |
 | Linux   | libimgui-java64.so    |
+| Linux ARM64 | libimgui-java64-arm64.so |
 | macOS   | libimgui-java64.dylib |
 
 ### Additional Information
 
 - All libraries include statically compiled **FreeType**.
+- `libimgui-java64-arm64.so` is the Linux aarch64 build. Its file name differs from the x86-64 one only because CI collects every platform into this single directory; when loading it by path, pass `-Dimgui.library.name=libimgui-java64-arm64.so`.
 - The macOS version is a universal library and support x86_64 and arm64 architectures.
 
 ### Continuous Integration

buildSrc/scripts/build.sh

@@ -77,6 +77,27 @@ case "$VTYPE" in
         fi
         echo "SO file copied to /tmp/imgui/dst/libimgui-java64.so successfully"
         ;;
+    linuxarm64)
+        echo "Running Gradle task for Linux ARM64 (native aarch64 host required)..."
+        ./gradlew imgui-binding:generateLibs -Denvs=linuxarm64 -Dfreetype=true
+        if [ $? -ne 0 ]; then
+            echo "Gradle task for Linux ARM64 failed"
+            exit 1
+        fi
+
+        echo "Checking if the generated SO file exists..."
+        check_file_exists /tmp/imgui/libsNative/linuxarm64/libimgui-java64.so
+
+        # Distinct name: CI merges every platform's output into one flat directory (bin/),
+        # so it must not collide with the x86-64 libimgui-java64.so.
+        echo "Copying the generated SO file to the destination directory..."
+        cp /tmp/imgui/libsNative/linuxarm64/libimgui-java64.so /tmp/imgui/dst/libimgui-java64-arm64.so
+        if [ $? -ne 0 ]; then
+            echo "Failed to copy SO file to /tmp/imgui/dst/libimgui-java64-arm64.so"
+            exit 1
+        fi
+        echo "SO file copied to /tmp/imgui/dst/libimgui-java64-arm64.so successfully"
+        ;;
     macos)
         echo "Running Gradle task for macOS and macOS ARM..."
         ./gradlew imgui-binding:generateLibs -Denvs=macos,macosarm64 -Dfreetype=true

buildSrc/scripts/publish.sh

@@ -40,6 +40,7 @@ publish_natives() {
 # Publish natives for each platform
 publish_natives "windows"
 publish_natives "linux"
+publish_natives "linuxarm64"
 publish_natives "macos"
 
 echo "> Nexus manual upload..."

buildSrc/scripts/vendor_freetype.sh

@@ -84,6 +84,10 @@ case "$VTYPE" in
     linux)
         build_freetype "-fPIC" "" "lib/libfreetype.a"
         ;;
+    linuxarm64)
+        # Built natively on an aarch64 host (e.g. the ubuntu-24.04-arm runner), so no --host/cross prefix.
+        build_freetype "-fPIC" "" "lib/libfreetype.a"
+        ;;
     macos)
         MACOS_VERSION=10.15
 

buildSrc/src/main/groovy/tool/generator/GenerateLibs.groovy

@@ -32,6 +32,7 @@ class GenerateLibs extends DefaultTask {
     private final String[] buildEnvs = System.getProperty('envs')?.split(',')
     private final boolean forWindows = buildEnvs?.contains('windows')
     private final boolean forLinux = buildEnvs?.contains('linux')
+    private final boolean forLinuxArm64 = buildEnvs?.contains('linuxarm64')
     private final boolean forMac = buildEnvs?.contains('macos')
     private final boolean forMacArm64 = buildEnvs?.contains('macosarm64')
 
@@ -120,10 +121,11 @@ class GenerateLibs extends DefaultTask {
         }
 
         if (forLinux) {
-            def linux64 = BuildTarget.newDefaultTarget(Os.Linux, Architecture.Bitness._64)
-            requireCpp17(linux64)
-            addFreeTypeIfEnabled(linux64)
-            buildTargets += linux64
+            buildTargets += createLinuxTarget(Architecture.x86)
+        }
+
+        if (forLinuxArm64) {
+            buildTargets += createLinuxTarget(Architecture.ARM)
         }
 
         if (forMac) {
@@ -145,6 +147,8 @@ class GenerateLibs extends DefaultTask {
             BuildExecutor.executeAnt(jniDir + '/build-windows64.xml', commonParams)
         if (forLinux)
             BuildExecutor.executeAnt(jniDir + '/build-linux64.xml', commonParams)
+        if (forLinuxArm64)
+            BuildExecutor.executeAnt(jniDir + '/build-linuxarm64.xml', commonParams)
         if (forMac)
             BuildExecutor.executeAnt(jniDir + '/build-macosx64.xml', commonParams)
         if (forMacArm64)
@@ -156,6 +160,8 @@ class GenerateLibs extends DefaultTask {
             checkLibExist("windows64/imgui-java64.dll")
         if (forLinux)
             checkLibExist("linux64/libimgui-java64.so")
+        if (forLinuxArm64)
+            checkLibExist("linuxarm64/libimgui-java64.so")
         if (forMac)
             checkLibExist("macosx64/libimgui-java64.dylib")
         if (forMacArm64)
@@ -170,6 +176,21 @@ class GenerateLibs extends DefaultTask {
         }
     }
 
+    BuildTarget createLinuxTarget(Architecture arch) {
+        def linuxTarget = BuildTarget.newDefaultTarget(Os.Linux, Architecture.Bitness._64, arch)
+        linuxTarget.libName = "libimgui-java64.so" // Lib for arm64 will be named the same for consistency.
+        if (arch == Architecture.ARM && System.getProperty('os.arch') in ['aarch64', 'arm64']) {
+            // gdx-jnigen defaults ARM Linux targets to the aarch64-linux-gnu- cross-compiler
+            // prefix. When already running natively on an aarch64 host (e.g. GitHub's
+            // ubuntu-24.04-arm runners) that prefix isn't needed, and the cross toolchain
+            // package providing it usually isn't installed there anyway.
+            linuxTarget.compilerPrefix = ''
+        }
+        requireCpp17(linuxTarget)
+        addFreeTypeIfEnabled(linuxTarget)
+        return linuxTarget
+    }
+
     BuildTarget createMacTarget(Architecture arch) {
         def minMacOsVersion = '10.15'
         def macTarget = BuildTarget.newDefaultTarget(Os.MacOsX, Architecture.Bitness._64, arch)

imgui-binding-natives/build.gradle

@@ -19,6 +19,7 @@ def packageDesc = 'Native binaries for imgui-java binding for Linux'
 def moduleName = 'imgui.natives.linux'
 def fromDir = '../bin'
 def libName = 'libimgui-java64.so'
+def jarLibName = null // set when the file name in bin/ differs from the name the loader expects on the classpath
 
 switch (findProperty('deployType')) {
     case 'windows':
@@ -33,6 +34,13 @@ switch (findProperty('deployType')) {
         moduleName = 'imgui.natives.linux'
         libName = 'libimgui-java64.so'
         break
+    case 'linuxarm64':
+        packageName = 'imgui-java-natives-linux-arm64'
+        packageDesc = 'Native binaries for imgui-java binding for Linux ARM64'
+        moduleName = 'imgui.natives.linux.arm64'
+        libName = 'libimgui-java64-arm64.so'
+        jarLibName = 'libimgui-java64.so'
+        break
     case 'macos':
         packageName = 'imgui-java-natives-macos'
         packageDesc = 'Native binaries for imgui-java binding for macOS'
@@ -45,6 +53,9 @@ jar {
     from(fromDir) {
         include "$libName" // this is fine
         into 'io/imgui/java/native-bin/'
+        if (jarLibName != null) {
+            rename { jarLibName }
+        }
     }
     manifest {
         attributes  'Automatic-Module-Name': moduleName