Stratagus

Stratagus is a free cross-platform real-time Strategy game engine used to build other games. Licensed under the GNU GPL, it is written in C with the configuration language being Lua. SDL, gzip and bzip2 are among the external libraries used.

History
On June 15, 1998 Lutz Sammer released the first public version of a free Warcraft II clone for Linux he had written, named ALE Clone. In 1999 it was renamed to Freecraft. In June 2003, a cease and desist letter was received from Blizzard Entertainment, who thought the name Freecraft could cause confusion with the names StarCraft and Warcraft, and that some of the ideas within the engine were too similar to Warcraft II. The project halted on June 20, 2003.

In 2004 the developers regrouped to continue the work by the name of Stratagus, with a change in the aim: former interest in using the data-files from WarCraft had diminished; the project using the data-files from Warcraft II was split-off into the new and separate project Wargus and the free media set imitating Warcraft II was discontinued. Development on Stratagus was paused on June 10, 2007. The Stratagus developers are now working on Bos Wars, which uses its own modified version of the Stratagus engine. In June 2010 some of developers moved Stratagus project from Sourceforge to Launchpad and started working on Stratagus and games again. Now Stratagus, Wargus and Stargus are developed by Stratagus team on Launchpad.

Playable Stratagus-based games are: fantasy Aleona's Tales, medieval Battle for Mandicor, Warcraft II: Tides of Darkness port Wargus, futuristic Battle of Survival, historically-inspired Commander Stalin, StarCraft port Stargus, and space age Astroseries. Of these, only Aleona's Tales and Wargus are complete.

Programming
The Stratagus engine is a 2D engine based on a set of pictures in a .png file to show animation. This style was commonly used in the time that Warcraft and other RTS had come out.

Basing on Lua as their primary scripting language, virtually all the abilities in the engine have been made available so that a user of Stratagus does not have to make changes in the original source unless he wishes to add new features not presently supported by the engine.

Stratagus and Wargus have been ported to run on Pocket PC, Symbian and Android devices. Wargus has also been ported to the GP2X Linux handheld.