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 SUPERTUXKART

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--------------------------------------------------------------------------------
 SYSTEM REQUIREMENTS
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To run SuperTuxKart on Android, you need a device that meets following
requirements:

- Android 4.4 or later
- Processor compatible with armv7 or x86
- GPU that supports OpenGL ES 3.0
- 1 GB RAM (STK uses ~150 MB in minimal configuration)
- 300 MB of free space on internal storage
- Touch screen or external keyboard



--------------------------------------------------------------------------------
 COMPILATION
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The build scripts are designed to run under linux. They may work under cygwin
after some tweaks, but atm. only linux is supported.

Dependencies list (may be incomplete):

    autoconf, automake, make, python, gradle, ant, imagemagick, cmake, 
    vorbis-tools

Additionally some dependencies for optimize_data script:

    advancecomp, libjpeg-progs, optipng

Before compilation you must download the package with dependencies from:
https://github.com/supertuxkart/dependencies
and extract it to stk-code/lib. It contains sources of libraries that are used
in STK, but are not availiable in stk-code repository (curl, freetype, openal).

You need also Android SDK for android-19 platform (the API for Android 4.4) and
Android NDK. Note that NDK >= r15b is atm. not supported. Version r12b is
strongly recommended, because it's known that it works without issues.

You need to create proper "android-sdk" and "android-ndk" symlinks in the
directory with Android project, so that the compilation script will have access
to the SDK and NDK. These paths can be also set in SDK_PATH and NDK_PATH 
environmental variables.

Before running the compilation, run the generate_assets script, so that
selected assets will be copied to "assets" directory, and then included in the
apk file.

You can select different karts and tracks by setting KARTS and TRACKS variables
in the generate_assets.sh script at the beginning of file.

When you are creating the assets directory manually, note that the
directories.txt file is urgently needed and it is used by the application for
extracting assets.

If the assets directory is already prepared, you can run "./make.sh" command to
build the project and create an apk file. Note that all arguments are passed to
the make command, so that you can run "./make.sh -j5" for multi-threaded build.

If you want to prepare a package for particular architecture, you can choose it
by setting the COMPILE_ARCH environmental variable. At this stage, supported
architectures are "armv7", "x86" and "aarch64". The default is "armv7".

You can choose build type by setting BUILD_TYPE environment variable to "debug"
or "release". The default is debug build. Note that if you choose release build,
you have to manually sign the apk with your key and run zipalign.

Additionally you can choose the build tool by setting BUILD_TOOL environment
variable to "gradle" or "ant". Note that ant has been already removed from
Android SDK, so you have to use SDK <= 25.2.5 for building with ant. By default 
the BUILD_TOOL is set to "gradle".

You can override the SDK build-tools version by setting the BUILD_TOOLS_VER
environment variable.

Basically if all dependencies are installed in the system, it should be enough
to just run:

    export SDK_PATH=/path/to/your/android/sdk
    export NDK_PATH=/path/to/your/android/ndk
    ./generate_assets.sh
    ./make.sh -j5



--------------------------------------------------------------------------------
 RELEASE BUILD
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Making a release build is similar to typical compilation, but there are few
additional things to do. 

You have to change version numbers. This is important, because assets manager
in STK checks these numbers and detects if already extracted data files are
up to date. So that when you will install new STK version, this will force new 
data extraction automatically.

So that you have to:

1. Change "data/supertuxkart.git" to "data/supertuxkart.VERSION_NUMBER"

2. Open "src/utils/constants.cpp" and change:

    const char STK_VERSION[] = "git";
      
   to
    
    const char STK_VERSION[] = "VERSION_NUMBER";
      
   where "VERSION_NUMBER" is for example "0.9.3" or "git20170409" or whatever.
    
3. You can also update these lines in "android/AndroidManifest.xml":
    android:versionCode="1"
    android:versionName="1.0"


Before compilation you have to set:

    export BUILD_TYPE=release

and then you make standard compilation with:

    ./generate_assets.sh
    ./make.sh -j5
    

The compiled apk is unsigned, so you have to sign it with your key. To sign it,
you have to run:

    jarsigner -verbose -sigalg SHA1withRSA -digestalg SHA1 -keystore \
        my-release-key.keystore SuperTuxKart-release-unsigned.apk alias_name
        
and then:

    zipalign -v 4 SuperTuxKart-release-unsigned.apk SuperTuxKart-release.apk