OpenXcom requires a vanilla version of the original X-COM resources. This can be any one of:
- DOS Version 1.4 (you can check if you have the correct version if it contains a "SOUND\GM.CAT" file)
- Windows Version / Collector's Edition
- Steam Version (you can find the game folder in "Steam\steamapps\common\xcom ufo defense\XCOM")
- Gog Version
First, you should decide what exactly you want to install.
- "Nightlies". Development versions - less polished, much more recent, not really nightly, but actually update every few months: released builds, repository.
- OpenXcom Extended, aka OXCE. Cutting edge, extra-modding-friendly development version: released builds, repository.
- And there's also available the OpenXcom 1.0 release but it has been discontinued a long time ago - use the nightlies or OXCE instead.
In the instructions below, we refer to three different folders a lot: the "data" folder, the "user" folder, and the "config" folder. See here for directory definitions and where they are located on your operating system.
Copy the original resources (specifically the GEODATA, GEOGRAPH, MAPS, ROUTES, SOUND, TERRAIN, UFOGRAPH, UFOINTRO, and UNITS subfolders) to OpenXcom's Data folder for version 1.0 or to the UFO folder in the User folder for the nightly. If using the nightly, you can alternately/additionally copy in Terror From the Deep files to the TFTD folder in your User folder to prepare for when the TFTD OpenXcom ruleset is released. Do not just drag/copy your whole X-COM folder into the Data folder, it won't work.
For version 1.0 it should end up like this:
and for the nightly it should look like this:
If you do this incorrectly, you'll get an error about "X not found". For more specific instructions, check your platform below.
A video tutorial that covers the installation of milestone version 1.0 is available here (courtesy of Ivan Dogovich). Though recorded for the Windows platform, check it out if you have doubts about a particular step during the installation.
This video: "OpenXCOM Nightly Install Tutorial" explains installing the Nightly (both with the installer and manually) and installing both simple and total conversion mods.
The installer will automatically detect Steam installations, patch the game and copy the original data for you, just follow the instructions.
Mac OS X
Copy the resources to the application's data resource (right click the application > Show Package Contents > Contents > Resources > data) for version 1.0 or the UFO and/or TFTD resources for the nightly.
OpenXcom requires the following libraries:
- SDL (libsdl1.2)
- SDL_mixer (libsdl-mixer1.2)
- SDL_gfx (libsdl-gfx1.2), version 2.0.22 or later
- SDL_image (libsdl-image1.2)
- yaml-cpp (libyaml-cpp), version 0.5.1 or later (please note that 0.5.2 has issues, use 0.5.3)
Check your distribution's package manager or the library website on how to install them.
Copy game resources to the appropriate folder locations.
To make a portable version of OpenXcom, just put all the files in the game folder, with a data (1.0) or UFO (nightly) subfolder for the resources and a user subfolder for your saves and settings (you may need to delete your old User Folder so the game doesn't use it instead).
In case you experience any problems or errors during the initial game loading/startup, these will be shown and logged in openxcom.log in the User Folder. Make sure you installed everything correctly as instructed, and if you still experience problems, check the forums.