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5 <h1 align="center">FlightGear FAQ</h1>
6 <p align="center"><small>Cameron Moore<br><a href="mailto:cameron@unbeatenpath.net?subject=FlightGear%20FAQ">cameron@unbeatenpath.net</a></small></p><hr noshade="yes">
10 <p>Welcome to the FlightGear FAQ. Here you will find the answers to
11 some questions that are frequently asked on our mailing lists. If
12 you have a question that is not answered here, feel free to ask
13 us on our mailing lists. Enjoy</p>
15 <hr noshade="yes"><h2><a name="toc">Table of Contents</a></h2><h4>1 -
16 <a href="#1">The FAQ</a></h4><div class="indent">1.1 -
17 <a href="#1.1">Where can I get the latest version of this FAQ?</a></div><div class="indent">1.2 -
18 <a href="#1.2">Who do I contact if I have comments about this FAQ?</a></div><div class="indent">1.3 -
19 <a href="#1.3">What other important documentation should I read?</a></div><div class="indent">1.4 -
20 <a href="#1.4">How old is this document?</a></div><br><h4>2 -
21 <a href="#2">Distribution</a></h4><div class="indent">2.1 -
22 <a href="#2.1">Where is the latest distribution of FlightGear?</a></div><div class="indent">2.2 -
23 <a href="#2.2">Where can I find the newest snapshots?</a></div><div class="indent">2.3 -
24 <a href="#2.3">Where can I fly and where do I get the scenery?</a></div><div class="indent">2.4 -
25 <a href="#2.4">Where can I get some different 3D models for my plane?</a></div><br><h4>3 -
26 <a href="#3">Compiling</a></h4><div class="indent">3.1 -
27 <a href="#3.1">Why won't FlightGear compile?</a></div><div class="indent">3.2 -
28 <a href="#3.2">I'm using RedHat 7, and ...?</a></div><br><h4>4 -
29 <a href="#4">Configuring</a></h4><div class="indent">4.1 -
30 <a href="#4.1">How do I install new scenery?</a></div><div class="indent">4.2 -
31 <a href="#4.2">How do I setup my joystick(s)?</a></div><br><h4>5 -
32 <a href="#5">Running</a></h4><div class="indent">5.1 -
33 <a href="#5.1">Why is FlightGear so slow?</a></div><div class="indent">5.2 -
34 <a href="#5.2">Why is my SGI machine so slow?</a></div><div class="indent">5.3 -
35 <a href="#5.3">Stuck upside down after "crash"?</a></div><div class="indent">5.4 -
36 <a href="#5.4">What happened to the panel, keyboard, etc?</a></div><div class="indent">5.5 -
37 <a href="#5.5">Why doesn't audio work properly under Irix?</a></div><div class="indent">5.6 -
38 <a href="#5.6">Why do I get an error loading libmk4.so.0?</a></div><br><h4>6 -
39 <a href="#6">Hacking</a></h4><div class="indent">6.1 -
40 <a href="#6.1">How do I design a flight dynamics model for a new plane?</a></div><div class="indent">6.2 -
41 <a href="#6.2">How do I import planes from Microsoft Flight Simulator?</a></div><div class="indent">6.3 -
42 <a href="#6.3">How do I import BGL scenery from Microsoft Flight Simulator?</a></div><div class="indent">6.4 -
43 <a href="#6.4">How do I design or modify a panel?</a></div><div class="indent">6.5 -
44 <a href="#6.5">How do I place objects, like buildings, into FlightGear?</a></div><br><h4>7 -
45 <a href="#7">Flying</a></h4><div class="indent">7.1 -
46 <a href="#7.1">Where can I learn about instrument flying and navigation?</a></div><div class="indent">7.2 -
47 <a href="#7.2">What is the difference between Aileron and Rudder?</a></div><br><h4>8 -
48 <a href="#8">FlightGear v0.7.6</a></h4><div class="indent">8.1 -
49 <a href="#8.1">Why do I get an error in viewer.cxx about `exit' being undeclared?</a></div><br>
52 <hr><h2><a name="1">1 -
54 <b><a name="1.1">1.1 -
55 <u>Where can I get the latest version of this FAQ?</u></a></b>
58 <a href="http://flightgear.org/Docs/FlightGear-FAQ.html">http://flightgear.org/Docs/FlightGear-FAQ.html</a>
62 <b><a name="1.2">1.2 -
63 <u>Who do I contact if I have comments about this FAQ?</u></a></b>
65 <p>First contact the author. If you get no response, send your
66 comments to the flightgear-users mailing list.</p>
69 <b><a name="1.3">1.3 -
70 <u>What other important documentation should I read?</u></a></b>
72 <p>Definitely read the <i>FlightGear Installation and Getting
73 Started</i> document available at
74 <a href="http://flightgear.org/Docs/">http://flightgear.org/Docs/</a>.</p>
75 <p>Also see the FlightGear/docs-mini/ directory in the source
76 distribution for various other helpful documents.</p>
79 <b><a name="1.4">1.4 -
80 <u>How old is this document?</u></a></b>
82 <p>See the <i>About This Document</i> section at the end of the FAQ.</p>
86 <hr><h2><a name="2">2 -
88 <b><a name="2.1">2.1 -
89 <u>Where is the latest distribution of FlightGear?</u></a></b>
92 <a href="http://flightgear.org/Downloads/">http://flightgear.org/Downloads/</a>.
96 <b><a name="2.2">2.2 -
97 <u>Where can I find the newest snapshots?</u></a></b>
99 <p>The best place to get the latest development code is from our CVS
101 <a href="http://flightgear.org/cvsResources/">http://flightgear.org/cvsResources/</a> for details.
103 <p>Otherwise, you can get relatively up-to-date snapshots of the
105 <a href="ftp://flightgear.sourceforge.net/pub/flightgear/Devel/Snapshots/">ftp://flightgear.sourceforge.net/pub/flightgear/Devel/Snapshots/</a>.
109 <b><a name="2.3">2.3 -
110 <u>Where can I fly and where do I get the scenery?</u></a></b>
112 <p>While the base package only comes with scenery for the San Francisco
113 Bay area, you can currently fly just about anywhere in the world.
114 See the <i>"Additional Scenery"</i> section of
115 <a href="http://flightgear.org/Downloads/">http://flightgear.org/Downloads/</a>
116 for more information or go directly to our graphical downloader at
117 <a href="http://flightgear.org/Downloads/world-scenery.html">http://flightgear.org/Downloads/world-scenery.html</a>.
119 <p>Also visit our <i>"Places to Fly"</i> section of the website
120 (<a href="http://flightgear.org/Places/">http://flightgear.org/Places/</a>)
121 for some help navigating to some awesome locations.</p>
124 <b><a name="2.4">2.4 -
125 <u>Where can I get some different 3D models for my plane?</u></a></b>
127 <p>We currently don't have any of our own models yet, but we have
128 been given permission by several people to convert their models (which
129 where originally intended for use with <i>Microsoft Flight
130 Simulator</i>) to use with FlightGear. See Wolfram's Hangar
131 (<a href="http://home.t-online.de/home/Wolfram.Kuss/">http://home.t-online.de/home/Wolfram.Kuss/</a>)
132 for a list of what we currently have available as well as
133 information on how to convert models yourself.</p>
137 <hr><h2><a name="3">3 -
139 <b><a name="3.1">3.1 -
140 <u>Why won't FlightGear compile?</u></a></b>
142 <p>Well, that depends. First make sure you are using the appropriate
143 versions of FlightGear, SimGear, and plib. If any of the packages are
144 out of sync with the others, compilation may fail.</p>
145 <p>The FlightGear <i>Downloads</i> page
146 (<a href="http://flightgear.org/Downloads/">http://flightgear.org/Downloads/</a>)
147 should tell you what versions you need if you are trying to compile
148 the latest stable release. If you are using a development snapshot,
149 make sure all three packages are up-to-date.</p>
150 <p>Also ensure that you have some implementation of OpenGL with glut
151 support with the appropriate header files. Linux users with nVidia
152 cards should make sure you have the latest drivers from nVidia. Other
153 Linux users make sure you have Mesa3D
154 (<a href="http://mesa3d.org">http://mesa3d.org</a>)
155 and your X server installed correctly. Windows users see
156 <a href="http://www.x-plane.com/SYSREQ/v5ibm.htm">http://www.x-plane.com/SYSREQ/v5ibm.html</a>,
158 <a href="http://www.x-plane.com/SYSREQ/v5mac.html">http://www.x-plane.com/SYSREQ/v5mac.html</a>.
160 <p>If your problems persist, subscribe to our FlightGear-Users mailing
161 list and let us know what problem you're having. See
162 <a href="http://flightgear.org/mail.html">http://flightgear.org/mail.html</a> for help with this.
166 <b><a name="3.2">3.2 -
167 <u>I'm using RedHat 7, and ...?</u></a></b>
169 <p>Update your gcc packages. See
170 <a href="http://redhat.com/errata/">http://redhat.com/errata/</a>
172 <a href="http://www.gnu.org/software/gcc/gcc-2.96.html">http://www.gnu.org/software/gcc/gcc-2.96.html</a>
173 for an explanation why.</p>
177 <hr><h2><a name="4">4 -
179 <b><a name="4.1">4.1 -
180 <u>How do I install new scenery?</u></a></b>
182 <p>The scenery archive files (ie. w100n30.tar.gz) should be untarred
183 into the <code>Scenery/</code> directory in your
184 <code>$FG_ROOT</code>.</p>
187 <b><a name="4.2">4.2 -
188 <u>How do I setup my joystick(s)?</u></a></b>
191 <p>FlightGear should come with a helpful program called <i>`fgjs`</i>
192 that can help configure your joystick.</p>
194 <p>See the README.Joystick file located in the
195 <code>FlightGear/docs-mini/</code> directory of the source
196 distribution. This document is mirrored at
197 <a href="http://rockfish.net/shell/aboutjoy.txt">http://rockfish.net/shell/aboutjoy.txt</a>.
199 <p>If you have a joystick with digital axes, see
200 <a href="http://www.unet.univie.ac.at/~a8603365/flightgear.html">http://www.unet.univie.ac.at/~a8603365/flightgear.html</a>
201 for a patch to the development version of FlightGear.</p>
205 <hr><h2><a name="5">5 -
207 <b><a name="5.1">5.1 -
208 <u>Why is FlightGear so slow?</u></a></b>
210 <p>FlightGear supports hardware acceleration, but it seems not to be
211 activated. Make sure you have OpenGL libraries installed and
212 configured properly and make sure you have the latest drivers for your
214 <p><b>Linux users</b>: If you are an nVidia user, follow their
215 directions on getting your card working. For most other users, make
216 sure Mesa is installed property and ensure that you have the
217 appropriate kernel device drivers for your card. Most people (and
218 distributions) use modules for their video card device drivers; run
219 <i>`lsmod`</i> as root to see what modules are loaded. You should also
220 make sure that you are loading the appropriate modules in your
221 XF86Config and that your video device section is correct. Now try
222 running an OpenGL application (other than FlightGear) to see how it
223 performs. You can try the <i>gears</i> demo from Mesa or something
224 like <i>Quake3</i>.</p>
227 <b><a name="5.2">5.2 -
228 <u>Why is my SGI machine so slow?</u></a></b>
230 <p>First of all, one of the most common mistakes on SGI hardware is to
231 forget to specify --fog-fastest. On most SGI machines the EXP2 shading
232 model isn't hardware supported resulting in frame rates below 1 frame
233 per second (fps).</p>
234 <p>FlightGear makes extensive use of the OpenGL z-buffer feature,which
235 on most older SGI hardware is only supported in software. This means
236 that the CPU has to do all the z-buffer calculations in addition to the
237 other tasks FlightGear involves (flight dynamics, scenery tracking,
238 pushing commands into the graphics queue, etc). The following features
239 are software rendered on low-end SGI machines (like Indy and
242 <li>stencil and accumulation buffer</li>
243 <li>depth queuing and depth buffering</li>
244 <li>fogging, lighting, clipping and transforms</li>
247 <p>This means that running FlightGear with the following options may not
248 even get the desired result:</p>
249 <p><code>./runfgfs --fog-disable --shading-flat --disable-skyblend \</code><br>
250 <code>--disable-textures --disable-clouds --disable-sound \</code><br>
251 <code>--disable-panel --enable-hud --disable-anti-alias-hud</code></p>
252 <p>I could even imagine that adding --enable-wireframe doesn't work on
253 these machines (I would be happy to be proven wrong though).</p>
254 <p>On a machine like O2 the following options give an acceptable
256 <code>./runfgfs --fog-fastest --disable-sound</code>
257 <p>Since I don't have access to other SGI hardware I can't tell which
258 options would be appropriate for your situation.</p>
261 <b><a name="5.3">5.3 -
262 <u>Stuck upside down after "crash"?</u></a></b>
264 <p>In his infinite wisdom the FlightGear Grand Master decided that
265 planes were to valuable to allow them to be destroyed by novice pilots
266 who seemed to crash a lot. The fact that nobody has bothered to model
267 crashes may have something to do with it too. :-)</p>
268 <p>The result of this as you have noticed is that with a little
269 practice an ingenuity you can trim the ship to fly inverted along the
271 <p>The quick answer is to hit Ctrl+U (with the default key bindings)
272 to warp the plane up 1000ft.</p>
273 <p>For the stubborn people out there: The trick to learn is to roll
274 back to normal (non inverted) do this by nursing the elevator to get
275 to about 500 feet or so and use the ailerons to snap roll 180*.
276 This is all good avionics except for the plane not destroying
277 itself. Remember the controls work in reverse when you are inverted
278 and keep that airspeed up!!!</p>
281 <b><a name="5.4">5.4 -
282 <u>What happened to the panel, keyboard, etc?</u></a></b>
284 <p>If you are using a development version of FlightGear, make
285 sure you also have the latest base package. See
286 <a href="http://rockfish.net/fg/">http://rockfish.net/fg/</a>
287 for details on getting the latest CVS version.</p>
290 <b><a name="5.5">5.5 -
291 <u>Why doesn't audio work properly under Irix?</u></a></b>
293 <p>FlightGear (as of June 2001) uses the Portable Libraries (PLIB)
294 for playing audio. The audio queue implementation of PLIB is far from
295 optimal (in fact it's just wrong). This seems to work on other
296 platforms quite well, but Irix expects things to be programmed
298 <p>There has been discussion about using OpenAL
299 (<a href="http://www.openal.org">http://www.openal.org</a>)
300 for the next release of both PLIB and FlightGear. Tests show that
301 the OpenAL audio implementation does the job right, meaning that
302 these audio problems should be gone by then. In the mean time it is
303 best to disable audio on Irix completely (by adding --disable-sound
304 either on the command line or to your <code>$HOME/.fgfsrc</code>
308 <b><a name="5.6">5.6 -
309 <u>Why do I get an error loading libmk4.so.0?</u></a></b>
311 <p>With the default installation, libmk4.so.0 is installed into
312 <code>/usr/local/lib</code>. You need to ensure that that path is
313 listed in <code>/etc/ld.so.conf</code>, then run <i>`ldconfig`</i>as
318 <hr><h2><a name="6">6 -
320 <b><a name="6.1">6.1 -
321 <u>How do I design a flight dynamics model for a new plane?</u></a></b>
324 <a href="http://jsbsim.sf.net">http://jsbsim.sf.net</a>.</p>
327 <b><a name="6.2">6.2 -
328 <u>How do I import planes from Microsoft Flight Simulator?</u></a></b>
331 <a href="http://home.t-online.de/home/Wolfram.Kuss/">http://home.t-online.de/home/Wolfram.Kuss/</a>.
335 <b><a name="6.3">6.3 -
336 <u>How do I import BGL scenery from Microsoft Flight Simulator?</u></a></b>
339 <a href="http://matrixsoft.50megs.com/BGL/">http://matrixsoft.50megs.com/BGL/</a>.
343 <b><a name="6.4">6.4 -
344 <u>How do I design or modify a panel?</u></a></b>
346 <p>See the README.xmlpanel file located in the
347 <code>FlightGear/docs-mini/</code> directory of the source
348 distribution. This document is mirrored at
349 <a href="http://rockfish.net/fg/README.xmlpanel">http://rockfish.net/fg/README.xmlpanel</a>.
353 <b><a name="6.5">6.5 -
354 <u>How do I place objects, like buildings, into FlightGear?</u></a></b>
356 <p>First, ensure that you have v0.7.7 or later, the scenery files
357 where you plan to place the object, the actual model, and the
358 longitude and latitude where you plan to place the object.</p>
359 <p>Now get the altitude for your point. If you don't want to
360 calculate this yourself, start FlightGear at your location and take
361 note of the altitude. Here's an example command:</p>
362 <p><code>fgfs --lat=45.50 --lon=-75.73 2>&1 | tee fgfs.log</code></p>
363 <p>The altitude is probably in feet, so divide the starting altitude
365 <p>Search the output log file for the first occurrence of the string
366 "Loading tile" and take note of the filename. In the above example,
367 the output line looks like:</p>
368 <p><code>Loading tile /usr/local/Scenery/w080n40/w076n45/1712601</code></p>
369 <p>Copy a 3D model in a format that Plib understands to the same
370 directory as the tile file. Edit the text file in that directory
371 consisting of the tile name with the extension ".ind". The file will
372 already exist if there is an airport on the tile; otherwise, you can
373 create it from scratch. In our example, the filename is:</p>
374 <p><code>/usr/local/Scenery/w080n40/w076n45/1712601.ind</code></p>
375 <p>At the end of the file, add a new entry for your object,
376 consisting of the word "OBJECT_STATIC" followed by the model name,
377 the longitude in degrees, the latitude in degrees, the altitude in
378 meters, and the heading in degrees. In our example the line looks
380 <p><code>OBJECT_STATIC Towerax.ac -75.73 45.40 60 0</code></p>
381 <p>Save the changes to the .ind file, restart FlightGear, and
383 <p>NOTE: The above information was taken from the following mailing
385 <a href="http://www.geocrawler.com/archives/3/11854/2001/6/0/5991409/">http://www.geocrawler.com/archives/3/11854/2001/6/0/5991409/</a>.
386 See that page if this one doesn't make sense.</p>
390 <hr><h2><a name="7">7 -
392 <b><a name="7.1">7.1 -
393 <u>Where can I learn about instrument flying and navigation?</u></a></b>
396 <a href="http://www.navfltsm.addr.com/">http://www.navfltsm.addr.com/</a>
397 is a very good site for learning techniques for navigation. Check
401 <b><a name="7.2">7.2 -
402 <u>What is the difference between Aileron and Rudder?</u></a></b>
404 <p>There is a bit of info on aileron vs. rudder here:
405 <a href="http://www.arundel.net/xplane/html/crosswind.html">http://www.arundel.net/xplane/html/crosswind.html</a>
407 <a href="http://www.monmouth.com/~jsd/how/">http://www.monmouth.com/~jsd/how/</a>.
412 <hr><h2><a name="8">8 -
413 FlightGear v0.7.6</a></h2>
414 <b><a name="8.1">8.1 -
415 <u>Why do I get an error in viewer.cxx about `exit' being undeclared?</u></a></b>
417 <p>This error cropped up after the release of v0.7.6. To fix the
418 problem, add "<code>#include <stdlib.h></code>" to the top of viewer.cxx.</p>
423 <hr noshade="yes"><a name="about"><h2>About This Document</h2></a><b>FlightGear FAQ</b><br>$Revision$<br>$Date$<br><p><small>
424 This document generated from XML using
425 <a href="http://www.gingerall.com/charlie-bin/get/webGA/act/sablotron.act">Sablotron</a>.
426 </small></p><address>Cameron Moore<br>cameron@unbeatenpath.net<br></address></body></html>