walisser/fg/.
This central chapter describes how to build FlightGear on several systems. In case you are on a Win32 (i. e. Windows95/98/ME/NT/2000/XP) platform or any of the other platforms which binary executables are available for, you may not want to go though that potentially troublesome process but skip that chapter instead and straightly go to the next one. (Not everyone wants to build his or her plane himself or herself, right?) However, there may be good reason for at least trying to build the simulator:
On the other hand, compiling FlightGear is not a task for novice users. Thus, if you’re a beginner (we all were once) on a platform which binaries are available for, we recommend postponing this task and just starting with the binary distribution to get you flying.
As you will notice, this Chapter is far from being complete. Basically, we describe compiling for two operating systems only, Windows and Linux, and for only one compiler, the GNU C compiler. FlightGear has been shown to be built under different compilers (including Microsoft Visual C) as well as different systems (Macintosh) as well. The reason for these limitations are:
You might want to check Section A, Missed approach, if anything fails during compilation. In case this does not help we recommend sending a note to one of the mailing lists (for hints on subscription see Chapter C).
There are several Linux distributions on the market, and most of them should work. Some come even bundled with (often outdated) versions of FlightGear. However, if you are going to download or buy a distribution, Debian (Woody) is suggested by most people. SuSE works well, too.
Contrary to Linux/Unix systems, Windows usually comes without any development tools. This way, you first have to install a development environment. On Windows, in a sense, before building the plane you will have to build the plant for building planes. This will be the topic of the following section, which can be omitted by Linux users.
There is a powerful development environment available for Windows and this even for free: The Cygnus development tools, resp. Cygwin. Their home is at
http://sources.redhat.com/cygwin/,
and it is always a good idea to check back what is going on there now and then.
Nowadays, installing Cygwin is nearly automatic. First, make sure the drive you want Cygwin, PLIB, SimGear and FlightGear to live on, has nearly 1 GB of free disk space. Create a temporary directory and download the installer from the site named above to that directory. (While the installer does an automatic installation of the Cygnus environment, it is a good idea to download a new installer from time to time.)
Invoke the installer now. It gives you three options. To avoid having to download stuff twice in case of a re-installation or installation on a second machine, we highly recommended to take a two-step procedure. First, select the option Download from Internet. Insert the path of your temporary directory, your Internet connection settings and then choose a mirror form the list. Near servers might be preferred, but may be sometimes a bit behind with mirroring. We found
a very recent and fast choice. In the next windows the default settings are usually a good start. Now choose Next, sit back and wait.
If you are done, invoke the installer another time, now with the option Install from local directory. After confirming the temporary directory you can select a root directory (acting as the root directory of your pseudo UNIX file system). Cygnus does not recommend taking the actual root directory of a drive, thus choose c:/Cygwin (while other drives than c: work as well). Now, all Cygwin stuff and all FlightGear stuff lives under this directory. In addition, select
Default text file type: Unix
You are free to install the compiler for all users or just for you.
As a final step you should include the binary directory (for instance: c:/Cygwin/bin) into your path by adding path=c:\Cygwin\bin in your autoexec.bat under Windows 95/98/ME. Under WindowsNT/2000/XP, use the Extended tab under the System properties page in Windows control panel. There you’ll find a button Environment variables, where you can add the named directory.
Now you are done. Fortunately, all this is required only once. At this point you have a nearly UNIX-like (command line) development environment. Because of this, the following steps are nearly identical under Windows and Linux/Unix.
A preliminary remark: For UNIX, make sure you have all necessary OpenGL libraries first. Fortunately on all recent Linux distributions (i.e. SuSE-7.1) these are already put on the right place. Be sure to install the proper package. Besides the basic X11 stuff you want to have - SuSE as an example - the following packages: mesa, mesa-devel, mesasoft, xf86_glx, xf86glu, xf86glu-devel, mesaglut, mesaglut-devel and plib.
Also you are expected to have a bunch of tools installed that are usually required to compile the Linux kernel. So you may use the Linux kernel source package top determine the required dependencies. The following packages might prove to be useful when fiddling with the FlightGear sources: automake, autoconf, libtool, bison, flex and some more, that are not required to build a Linux kernel.
Please compare the release of the Plib library with the one that ships with your Linux distribution. It might be the case that FlightGear requires a newer one that is not yet provided by your vendor.
Under Windows, the required libraries should have been installed with the Cygwin installation above.
The following steps are identical under Linux/Unix and under Windows with minor modifications. Under Windows, just open the Cygwin icon from the Start menu or from the desktop to get a command line.
To begin with, the FlightGear build process is based on four packages which you need to built and installed in this order:
cd:/usr/local/
mkdir source
to /usr/local/source. Change to that directory and unpack PLIB using
tar xvfz plib-X.X.X.tar.gz.
cd into plib-X.X.X and run
./configure
make
make install.
Under Linux, you have to become root for being able to make install, for instance via the su command.
Confirm you now have PLIB’s header files (as ssg.h etc.) under /usr/include/plib (and nowhere else).
ftp://ftp.simgear.org/pub/simgear/Source/
Download it to /usr/local/source. Change to that directory and unpack SimGear using
tar xvfz SimGear-X.X.X.tar.gz.
cd into SimGear-X.X.X and run
./configure
make
make install
Again, under Linux, you have to become root for being able to make install, for instance via the su command.
ftp://www.flightgear.org/pub/flightgear/Source/
and download it to /usr/local/source. Unpack FlightGear using
tar xvfz FlightGear-X.X.X.tar.gz.
cd into FlightGear-X.X.X and run
./configure
configure knows about numerous options, with the more relevant ones to be specified via switches as
A good choice would be --prefix=/usr/local/FlightGear. In this case FlightGear’s binaries will live under /usr/local/FlightGear/bin. (If you don’t specify a --prefix the binaries will go into /usr/local/bin while the base package files are expected under /usr/local/lib/FlightGear.)
Assuming configure finished successfully, run
make
make install.
Again, under Linux, you have to become root for being able to make install, for instance via the su command.
Note: You can save a significant amount of space by stripping all the debugging symbols off the executable. To do this, make a
cd /usr/local/FlightGear/bin
to the directory in the install tree where your binaries live and run
strip *.
This completes building the executable and should result in a file fgfs (Unix) or fgfs.exe (Windows) under /usr/local/FlightGear/bin
Note: If for whatever reason you want to re-build the simulator, use the command make distclean either in the SimGear-X.X.X or in the FlightGear-X.X.X directory to remove all the build. If you want to re-run configure (for instance because of having installed another version of PLIB etc.), remove the files config.cache from these same directories before.
For compiling under Mac OS 10.1 you will need
This will need a bit more bravery than building under Windows or Linux. First, there are less people who tested it under sometimes strange configurations. Second, the process as described here itself nees a touch more experience by using CVS repositories.
First, download the development files. They are intended to simplify the build process as much as possible:
http://expert.cc.purdue.edu/ walisser/fg/fgdev.tar.gz
Once you have this extracted, make sure you are using tcsh, since the setup script requires it.
Compiling on other Unix systems - at least on IRIX and on Solaris, is pretty similar to the procedure on Linux - given the presence of a working GNU C compiler. Especially IRIX and also recent releases of Solaris come with the basic OpenGL libraries. Unfortunately the ”glut” libraries are mostly missing and have to be installed separately (see the introductory remark to this chapter). As compilation of the ”glut” sources is not a trivial task to everyone, you might want to use a pre-built binary. Everything you need is a static library ”libglut.a” and an include file ”glut.h”. An easy way to make them usable is to place them into /usr/lib/ and /usr/include/GL/. In case you insist on building the library yourself, you might want to have a look at FreeGLUT
http://freeglut.sourceforge.net/
which should compile with minor tweaks. Necessary patches might be found in
ftp://ftp.uni-duisburg.de/X11/OpenGL/freeglut_portable.patch
Please note that you do not want to create 64 bit binaries in IRIX with GCC (even if your CPU is a R10/12/14k) because GCC produces a broken ”fgfs” binary (in case the compiler does’nt stop with ”internal compiler error”). Things might look better if Eric Hofman manages to tweak the FlightGear sources for proper compiling with MIPSPro compiler (it’s already mostly done).
There should be a workplace for Microsoft Visual C++ (MSVC6) included in the official FlightGear distribution. Macintosh users find the required CodeWarrior files as a .bin archive at
http://icdweb.cc.purdue.edu/ walisser/fg/.
Numerous (although outdated, at times) hints on compiling on different systems are included in the source code under docs-mini.
If you succeeded in performing the steps named above, you will have a directory holding the executables for FlightGear. This is not yet sufficient for performing FlightGear, though. Besides those, you will need a collection of support data files (scenery, aircraft, sound) collected in the so-called base package. In case you compiled the latest official release, the accompanying base package is available from
ftp://www.flightgear.org/pub/flightgear/Shared/fgfs-base-X.X.X.tar.gz.
This package is usually quite large (around 25 MB), but must be installed for FlightGear to run. There is no compilation required for it. Just download it to /usr/local and install it with
tar xvfz fgfs-base-X.X.X.tar.gz.
Now you should find all the FlightGear files under /usr/local/Flightgear in the following directory structure::
/usr/local/Flightgear
/usr/local/Flightgear/Aircraft
/usr/local/Flightgear/Aircraft-uiuc
. . .
/usr/local/Flightgear/bin
. . .
/usr/local/Flightgear/Weather.
It you are into adventures or feel you’re an advanced user, you can try one of the recent bleeding edge snapshots at
http://www.flightgear.org/Downloads/.
In this case you have to get the most recent Snapshot from SimGear at
http://www.simgear.org/downloads.html
as well. But be prepared: These are for development and may (and often do) contain bugs.
If you are using these CVS snapshots, the base package named above will usually not be in sync with the recent code and you have to download the most recent developer’s version from
We suggest downloading this package fgfs_base-snap.X.X.X.tar.gz to a temporary directory. Now, decompress it using
tar xvfz fgfs_base-snap.X.X.X.tar.gz.
Finally, double-check you got the directory structure named above.