Changes for linux compile.

README.md

@@ -6,3 +6,68 @@ stand in your way. The fate of your empire depends on your ability to master
 the economy, field a military, influence galactic politics, and learn what you
 can about the universe.
 
+## What is this?
+This repository contains the full source code needed to build Star Ruler 2, and
+all secondary scripts, data files and assets required to run it.
+
+Blind Mind Studios has been inactive for a few years now, so we decided to
+open-source the game as a whole and allow anyone interested in how its engine works
+to tinker with it.
+
+## Building the Game
+The Star Ruler 2.exe contained in the main folder is just a launcher. To run
+the game you will need to build the binary for your platform from source.
+
+### Building on Windows
+You will need Visual Studio 2017 to build Star Ruler 2 on windows. Simply open the
+visual studio solution in source/msvc/Star Ruler 2/, and build the "Star Ruler 2" project
+in either Debug or Non-Steam Release configuration.
+
+Please note that while the built exe ends up in the bin/win64/ directory, it expects to be
+started with its working directory set to the main direcotry (where the
+launcher exe is). So when debugging from visual studio, make sure the 'Working
+Directory' configuration property is set to ../.../..
+
+### Building on Linux
+The equivalent launcher on linux is StarRuler2.sh. To build the binary files on linux,
+make sure your working directory is set to the main directory (the one with StarRuler2.sh in it),
+then run `make -f source/linux/Makefile compile` to compile the binary.
+
+Afterward, run the `StarRuler2.sh` shell script to start the game.
+
+Several dependencies are required to build on linux, including libpng, zlib,
+GLEW, GLU, freetype2, libvorbisfile, libvorbis, libogg, libopenal, libbz2,
+libXRandR, and libcurl.
+
+
+## Differences with Commercial Version
+* The music is not part of the open source release of Star Ruler 2. The data/music/ directory from the commercial
+  release can be copied directly into the data/ directory of an open-source build. The music will be detected and played.
+* All code for accessing the SteamWorks API has been removed. The game platform abstraction layer game\_platform.h has 
+  been kept intact, so other mod-sharing platforms could potentially be integrated into the game.
+* Code for the automatic game patcher that is part of the GOG.com release is part of the repository, but the functionality
+  is disabled, since it relies on delta updates and will not work with modified open source versions.
+* While the actual source code is probably still compatible with 32-bit platforms, project files and external dependencies for
+  32-bit builds are not included in this repository.
+
+## FAQ
+### Can I Play Multiplayer with Steam/GOG versions?
+Yes. The base open source version is multiplayer-compatible with the commercial versions. If you make multiplayer-incompatible
+changes to the open source version, please remember to change the MP\_VERSION identifier in scripts/definitions/version.as,
+so things do not break from people with incompatible versions trying to join each other.
+
+### Does this have the Wake of the Heralds DLC Expansion?
+Yes. The code has been modified to bypass all DLC checks and unlock it by default. The Wake of the Heralds content
+is always available in the open-source version.
+
+### Is there a Community?
+Most Star Ruler 2 community activity is centered around the [Steam Forums](https://steamcommunity.com/app/282590/discussions/)
+(it is possible to post without owning the game on steam), and the [Discord Server for Rising Stars](https://discord.gg/9YyXgbh),
+one of the largest SR2 mod projects.
+
+## Licensing
+Star Ruler 2 source code is licensed as MIT, art assets are licensed as CC-BY-NC 2.0.
+
+Some third party code is contained in this repository as dependencies. Licenses for those projects are contained in the appropriate source folders.
+
+See the COPYING file for more information.