Attention: Here be dragons

This is the latest (unstable) version of this documentation, which may document features not available in or compatible with released stable versions of Redot.

Compiling for Android

See also

This page describes how to compile Android export template binaries from source. If you're looking to export your project to Android instead, read Exporting for Android.

Note

In most cases, using the built-in deployer and export templates is good enough. Compiling the Android APK manually is mostly useful for custom builds or custom packages for the deployer.

Also, you still need to follow the steps mentioned in the Exporting for Android tutorial before attempting to build a custom export template.

Requirements

For compiling under Windows, Linux or macOS, the following is required:

  • Python 3.6+.

  • SCons 3.1.2+ build system.

  • Android SDK (command-line tools are sufficient).

    • Required SDK components will be automatically installed.

    • On Linux, do not use an Android SDK provided by your distribution's repositories as it will often be outdated.

    • On macOS, do not use an Android SDK provided by Homebrew as it will not be installed in a unified location.

  • Gradle (will be downloaded and installed automatically if missing).

  • JDK 17 (either OpenJDK or Oracle JDK).

    • You can download a build from Adoptium.

See also

To get the Redot source code for compiling, see Getting the source.

For a general overview of SCons usage for Redot, see Introduction to the buildsystem.

Setting up the buildsystem

  • Set the environment variable ANDROID_HOME to point to the Android SDK. If you downloaded the Android command-line tools, this would be the folder where you extracted the contents of the ZIP archive.

    • Windows: Press Windows + R, type "control system", then click on Advanced system settings in the left pane, then click on Environment variables on the window that appears.

    • Linux or macOS: Add the text export ANDROID_HOME="/path/to/android-sdk" to your .bashrc or .zshrc where /path/to/android-sdk points to the root of the SDK directories.

  • Install the necessary SDK components in this folder:

    • Accept the SDK component licenses by running the following command where android_sdk_path is the path to the Android SDK, then answering all the prompts with y:

    cmdline-tools/latest/bin/sdkmanager --sdk_root=<android_sdk_path> --licenses
    
    • Complete setup by running the following command where android_sdk_path is the path to the Android SDK.

    cmdline-tools/latest/bin/sdkmanager --sdk_root=<android_sdk_path> "platform-tools" "build-tools;34.0.0" "platforms;android-34" "cmdline-tools;latest" "cmake;3.10.2.4988404" "ndk;23.2.8568313"
    
  • After setting up the SDK and environment variables, be sure to restart your terminal to apply the changes. If you are using an IDE with an integrated terminal, you need to restart the IDE.

  • Run scons platform=android. If this fails, go back and check the steps. If you completed the setup correctly, the NDK will begin downloading. If you are trying to compile GDExtension, you need to first compile the engine to download the NDK, then you can compile GDExtension.

Building the export templates

Redot needs three export templates for Android: the optimized "release" template (android_release.apk), the debug template (android_debug.apk), and the Gradle build template (android_source.zip). As Google requires all APKs to include ARMv8 (64-bit) libraries since August 2019, the commands below build templates containing both ARMv7 and ARMv8 libraries.

Compiling the standard export templates is done by calling SCons from the Redot root directory with the following arguments:

  • Release template (used when exporting with Debugging Enabled unchecked)

scons platform=android target=template_release arch=arm32
scons platform=android target=template_release arch=arm64 generate_apk=yes
  • Debug template (used when exporting with Debugging Enabled checked)

scons platform=android target=template_debug arch=arm32
scons platform=android target=template_debug arch=arm64 generate_apk=yes
  • (Optional) Dev template (used when troubleshooting)

scons platform=android target=template_debug arch=arm32 dev_build=yes
scons platform=android target=template_debug arch=arm64 dev_build=yes generate_apk=yes

The resulting templates will be located under the bin directory:

  • bin/android_release.apk for the release template

  • bin/android_debug.apk for the debug template

  • bin/android_dev.apk for the dev template

  • bin/android_source.zip for the Gradle build template

Note

  • If you are changing the list of architectures you're building, remember to add generate_apk=yes to the last architecture you're building, so that the template files are generated after the build.

  • To include debug symbols in the generated templates, add the debug_symbols=yes parameter to the SCons command.

See also

If you want to enable Vulkan validation layers, see Vulkan validation layers on Android.

Adding support for x86 devices

If you also want to include support for x86 and x86_64 devices, run the SCons command a third and fourth time with the arch=x86_32, and arch=x86_64 arguments before building the APK with Gradle. For example, for the release template:

scons platform=android target=template_release arch=arm32
scons platform=android target=template_release arch=arm64
scons platform=android target=template_release arch=x86_32
scons platform=android target=template_release arch=x86_64 generate_apk=yes

This will create template binaries that works on all platforms. The final binary size of exported projects will depend on the platforms you choose to support when exporting; in other words, unused platforms will be removed from the binary.

Cleaning the generated export templates

You can use the following commands to remove the generated export templates:

cd platform/android/java
# On Windows
.\gradlew clean
# On Linux and macOS
./gradlew clean

Using the export templates

Redot needs release and debug binaries that were compiled against the same version/commit as the editor. If you are using official binaries for the editor, make sure to install the matching export templates, or build your own from the same version.

When exporting your game, Redot uses the templates as a base, and updates their content as needed.

Installing the templates

The newly-compiled templates (android_debug.apk , android_release.apk, and android_source.zip) must be copied to Redot's templates folder with their respective names. The templates folder can be located in:

  • Windows: %APPDATA%\Godot\export_templates\<version>\

  • Linux: $HOME/.local/share/godot/export_templates/<version>/

  • macOS: $HOME/Library/Application Support/Godot/export_templates/<version>/

<version> is of the form major.minor[.patch].status using values from version.py in your Redot source repository (e.g. 4.1.3.stable or 4.2.dev). You also need to write this same version string to a version.txt file located next to your export templates.

However, if you are writing your custom modules or custom C++ code, you might instead want to configure your template binaries as custom export templates here:

../../../_images/andtemplates.png

You don't even need to copy them, you can just reference the resulting file in the bin\ directory of your Redot source folder, so that the next time you build you will automatically have the custom templates referenced.

Building the Redot editor

Compiling the editor is done by calling SCons from the Redot root directory with the following arguments:

scons platform=android arch=arm32 production=yes target=editor
scons platform=android arch=arm64 production=yes target=editor
scons platform=android arch=x86_32 production=yes target=editor
scons platform=android arch=x86_64 production=yes target=editor generate_apk=yes
  • You can add the dev_build=yes parameter to generate a dev build of the Redot editor.

  • You can add the debug_symbols=yes parameter to include the debug symbols in the generated build.

  • You can skip certain architectures depending on your target device to speed up compilation.

Remember to add generate_apk=yes to the last architecture you're building, so that binaries are generated after the build.

The resulting binaries will be located under bin/android_editor_builds/.

Removing the Editor binaries

You can use the following commands to remove the generated editor binaries:

 cd platform/android/java
 # On Windows
.\gradlew clean
# On Linux and macOS
./gradlew clean

Installing the Redot editor APK

With an Android device with Developer Options enabled, connect the Android device to your computer via its charging cable to a USB/USB-C port. Open up a Terminal/Command Prompt and run the following commands from the root directory with the following arguments:

adb install ./bin/android_editor_builds/android_editor-release.apk

Troubleshooting

Platform doesn't appear in SCons

Double-check that you've set the ANDROID_HOME environment variable. This is required for the platform to appear in SCons' list of detected platforms. See Setting up the buildsystem for more information.

Application not installed

Android might complain the application is not correctly installed. If so:

  • Check that the debug keystore is properly generated.

  • Check that the jarsigner executable is from JDK 8.

If it still fails, open a command line and run logcat:

adb logcat

Then check the output while the application is installed; the error message should be presented there. Seek assistance if you can't figure it out.

Application exits immediately

If the application runs but exits immediately, this might be due to one of the following reasons:

  • Make sure to use export templates that match your editor version; if you use a new Redot version, you have to update the templates too.

  • libgodot_android.so is not in libs/<arch>/ where <arch> is the device's architecture.

  • The device's architecture does not match the exported one(s). Make sure your templates were built for that device's architecture, and that the export settings included support for that architecture.

In any case, adb logcat should also show the cause of the error.