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README.md

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 # Custom ArmA 3 Launcher
-wip
+This is the official launcher/download-client of <a href="https://the-town.net/" target="_blank">the-town.net</a>.  
+
+This launcher uses a differential download method called <a href="http://zsync.moria.org.uk/" target="_blank">zsync</a>.
+This means that only changes between any old versions of the files on the computer and the files provided online are downloaded.
+
+> An optimised client-side implementation of the rsync algorithm. It allows updating of files from a remote web server, with efficiency approaching that of rsync -z, without requiring a special remote server application.
+
+
+### Configure
+If you want to use our launcher for your project, **please change the icons**!
+Open ``gui/src/main/resources/arma3launcher.json`` and edit the variables as you need.
+To configure your logo replace the _logo\*_ files inside the ``gui/src/main/resources/icons/`` folder.
+
+### Build
+To build this project simply run
+```bash
+mvn package
+```
+
+After building the package you find the universal auto patcher inside ``patcher/target/patcher.jar``.
+Inside ``gui/target/`` you find the gui as jar, jar with dependencies, jar wrapper build with launch4j and an assembled zip file.
+
+### Distribute
+After building the package you find inside the ``gui/target/`` folder an zip file.
+This zip file contains an empty ``jre/`` and an empty ``logs/`` folder.
+Bundle your own JRE with minimum JRE12 and put it in the ``*.zip/jre/``.  
+
+Linux/Mac users can run the *arma3launcher-gui.jar*.  
+Windows users can simply run the *arma3launcher.exe* and the launch4j wrapper prioritize the local JRE else use the bundled jre. 
+
+### Server side setup
+For the server side you need a simple webserver with no special configuration.
+
+The server side setup/configuration is done inside the ``<webserver root>/.sync/`` folder.
+Upload the files from ``linux/.sync/`` to ``<webserver root>/.sync/``.
+#### generateRepo.sh
+The *generateRepo.sh* is very important to run after every update of mods.
+Add new mods simply to ``<webserver root>``.
+
+You should generate the repository locally and update the changes via rsync.
+On Windows choose mingw or the linux subsystem.
+````bash
+rsync -a --exclude 'generateRepo.sh*' ./ remote_user@remote_host_or_ip:<webserver root>
+````
+#### modset.json
+The *modset.json* file is generated automatically by running the generateRepo.sh.
+It is containing the folder structure as well as the file sizes and sha1 sums. 
+
+#### server.json
+The *server.json* file contains all server as well as the modsets.
+The modsets are simply strings that should equal the corresponding folder.  
+Please see the example file.
+
+### changelog.txt
+The *changelog.txt* is a plain text file to write your changelogs for the modpacks, client or what ever.  
+The file is caches for 5 minutes and only loaded if the user switches the tab to the changelog tab.
+
+#### version.txt
+The *version.txt* is used for the autoupdater. It contains one line:
+```
+x.x.x:FILE.jar
+```
+
+*x.x.x* is the new version. *FILE.jar* is the new file that the client will download inside the ``<webserver root>/.sync/`` folder.
+
+#### patcher.jar
+The *patcher.jar* is a universal patcher and should not need to be updated. 
+The client download the patcher just once the ``%APDATA%/<launcher name>`` directory and only if a new version is available.
+If the *patcher.jar* already exists, the client skips the download.
+
+#### arma3launcher.jar
+The *arma3launcher.jar* is only a representation of the *FILE.jar*. See **version.txt**.
+
+## Screenshots
+<img src="screenshots/servertab.png" alt="server" width="500px"/>  
+
+<img src="screenshots/updatetab.png" alt="server" width="500px"/>  
+
+<img src="screenshots/presetstab.png" alt="server" width="500px"/>  
+
+<img src="screenshots/settingstab.png" alt="server" width="500px"/>