This is vamos.info, produced by makeinfo version 4.6 from vamos.texi.

INFO-DIR-SECTION Applications
START-INFO-DIR-ENTRY
* Vamos: (vamos).               An automotive simulator
END-INFO-DIR-ENTRY

   Vamos Automotive Simulator, by Sam Varner.

   This file documents the Vamos libraries and application.

   Copyright 2001-2003 Sam Varner

   Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.1 or
any later version published by the Free Software Foundation; with no
Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
Texts.  A copy of the license is included in the section entitled "GNU
Free Documentation License".

   Permission is granted to copy and distribute modified versions of
this manual under the conditions for verbatim copying, provided that the
entire resulting derived work is distributed under the terms of a
permission notice identical to this one.

   Permission is granted to copy and distribute translations of this
manual into another language, under the above conditions for modified
versions, except that this permission notice may be stated in a
translation approved by the Free Software Foundation.


File: vamos.info,  Node: Top,  Next: Let's Go,  Prev: (dir),  Up: (dir)

Vamos Automotive Simulator
**************************

Sam Varner <snick dash a dash doo @ comcast dot net>

   Vamos is an automotive simulation framework with an emphasis on
thorough physical modeling and good C++ design. Vamos includes a
real-time, first-person, 3D driving application.

   This file documents Vamos version 0.4.0.

* Menu:

* Let's Go::                    Getting on the road.
* Controls::                    Keyboard and joystick settings.
* Dashboard::                   On-screen information.
* Cars::                        Choosing and creating cars.
* Tracks::                      Choosing and creating tracks.
* Worlds::                      Specifying environments.
* Units::                       A note about units of measure.
* Code Reference::              The inner workings.
* Building Vamos::              Downloading and compiling the program.
* Copying::                     The GNU Free Documentation License.
* Concept Index::               An item for each concept.


File: vamos.info,  Node: Let's Go,  Next: Controls,  Prev: Top,  Up: Top

Let's Go
********

The `vamos' application lets you experience the simulation first hand.
Its main purpose is to be a test bed for the libraries.  It is not
intended to be a polished end-user application.  However, you can drive
on a number of tracks and try to beat your best time.  Or you can just
have fun driving on, and over, the ragged edge.

   When you start the application you will be looking out over the hood
of your car, down the front straight of a simple, fictitious circuit.
Give the car a little gas and shift into first by pressing and
releasing the first joystick button.  The clutch is engaged gradually,
so you will need to increase the throttle to keep the engine revs up.
If you stall, shift back to neutral (second button) and press the <s>
key to restart the engine.  *Note Controls::.

   Once you get going you will need to shift into second.  When you
press the button to shift, the clutch is disengaged.  It is re-engaged
when you release the button.  You will need to back off the throttle
when the clutch is disengaged in order to make your shifts smooth.  As
with shifting to first gear, the clutch is engaged gradually, although
much more quickly.

   The first turn on the circuit is a sharp left-hander at the top of a
hill.  This is a good place to practice sliding the car through a turn.
You will probably hear the tires slide as you enter the turn.  Don't
worry, the tires actually have _more_ grip when they're sliding a
little.  However, you do lose some directional stability.  So you point
the nose a little toward the center of the turn and use the throttle to
hold the car in the turn.  If you slide the car more than a little, you
will lose grip and probably find yourself in the barriers.

   When driving on the edge, the throttle and brake do as much as the
steering wheel to control the trajectory of the car.  In general,
accelerating tends to straighten out the car and braking tends to turn
the car more.  To demonstrate this, try backing off the throttle midway
through a turn.  You'll find that the back end steps out a little
causing the car to turn in.

   To recap, you will slide a little sideways through the turns,
steering with the brake and throttle.  You will also be trying to take a
perfect racing line, braking as late as possible and accelerating as
early as possible.  Just remember that the <r> key puts you back on the
road, pointed in the right direction.  *Note Controls::.


File: vamos.info,  Node: Controls,  Next: Dashboard,  Prev: Let's Go,  Up: Top

Controls
========

The car can be driven with keys or a joystick.  A joystick is highly
recommended.

   Keys, buttons, and joystick axes are mapped to functions in an XML
file in the data directory (usually `/usr/local/share/vamos/controls').
By default the file `default-controls' is used.  You can specify a
different file with the `-a' or `--controls=' options.  The default
control bindings are as follows:

Key         Stick              Action
<Up>*       Forward            Throttle.
<Down>*     Backward           Brake.
<Left>*     Left               Turn left.
<Right>*    Right              Turn right.
<Insert>*   Button-1*          Shift up.
<Delete>*   Button-2*          Shift down.
<Home>*     Button-3*          Clutch.
<a>                            Place the car back at the starting line.
<r>                            Place the car back on the road.
<s>                            Start the engine after a stall.
<f>                            Fill the fuel tank.
<c>                            Reload the car definition file.
<t>                            Reload the track definition file.
<p>                            Pause the application.
<q>                            Exit the application.
<F9>                           Cycle through the views.

   The `*' symbol indicates that the action is performed gradually after
the key or button is pressed.

   When shifting, pressing the key or button causes the clutch to be
disengaged before the new gear is selected.  Releasing the button
releases the clutch.  The clutch is engaged slowly when shifting from
neutral, and more quickly for other gears.  The clutch is always
disengaged quickly.

Control File Format
===================

Here's the format of a controls file.

     <controls name="Name">
       <!-- Key Binding -->
       <bind>
         <function>function name</function>
         <key>k</key>[<up|down/>]
         [<time>t</time>]
       </bind>
     
       <!-- Button Binding -->
       <bind>
         <function>function name</function>
         <button>b</button>[<up|down/>]
       </bind>
     
       <!-- Axis Binding -->
       <bind>
         <function>function name</function>
         <axis>a</axis>
         [<factor>f</factor>]
         [<offset>o</offset>]
         [<minimum>m</minimum>]
       </bind>
     </controls>

   The `function' tag gives the name of the function to bind.  Any
member funciton of Gl_Car_World that takes two double arguments and
returns a bool can be bound.  The case of the name inside the
`function' tag must match the actual function's name, and underscores
must be replaced with single spaces.

   The `down' tag binds the function to a key (or button) press; `up'
binds it to a key release.  If neither is specified, the function is
bound to a key press.

   The `time' tag sets how long it takes for setting to be ramped up to
its target value.  It is used for controling continuous values, like
throttle, from the keyboard.  The default time is 0.

   For joystick axes, vaules range from -1 to 1.  This number is
multiplied by the value in the `factor' tag and then the value in the
`offset' tag is added.  The result is clipped at `minimum'.  The
defaults are 1, 0, 0, respectively.

Bindable Functions
------------------

These are the functions that can be bound to controls.

`pause'
     Pause the simulation.

`quit'
     Quit the program.

`cycle view'
     Change the point-of-view from car to trackside to overhead.

`read car'
     Read the car definition file.

`read track'
     Read the track definition file.

`read world'
     Read the world definition file.

`restart car'
     Put the car at the starting line.

`reset car'
     Put the car back on the track.

`fill tank'
     Fill the car's gas tank.

`gas'
     Operate the throttle.

`brake'
     Operate the brakes.

`steer'
`steer left'
`steer right'
     Operate the steering wheel.  The 'steer left' and 'steer right'
     functions are useful for binding to keys.

`shift up'
`shift down'
     Select an adjacent gear, except when in neutral.

`shift up disengage'
`shift down disengage'
     Select an adjacent gear and operate the clutch, except when in
     neutral.

`initial shift up'
`initial shift down'
     Select an adjacent gear when in neutral.

`initial shift up disengage'
`initial shift down disengage'
     Select an adjacent gear and operate the clutch when in neutral.

`clutch'
     Operate the clutch.

`engage clutch'
`disengage clutch'
     Operate the clutch, except when in neutral

`initial engage clutch'
`initial disengage clutch'
     Operate the clutch when in neutral

   A function can be bound to more than one control.  However, when the
simulation is running, the joystick is read after the keys.  If, for
example, you bind the throttle to the up arrow key and to a joystick
axis, the joystick (if present) will override the keyboard.

   Similarly, more than one function can be bound to a control.  Each
function is called in turn until one of them returns true.

   For shifting, you will likely bind two functions to each shifting
control, one for shifting from neutral (e.g. `initial shift up') and
the other for shifting from other gears (e.g. `shift up').  If you bind
the clutch to a key or button, rather than a continuous contral, you
will also bind two functions to the clutch controls.  The reason is
that you may want different behavior from the clutch in these two
situations.

   When shifting from neutral to first, you will let the clutch out
slowly to get the car started without stalling.  When shifting to other
gears you will operate the clutch more quickly.  You can make this
happen by binding both `initial shift up disegnage' and `shift up
disengage' to the same key or button, and using a larger value in the
`time' tage for `initial shift up disengage'.


File: vamos.info,  Node: Dashboard,  Next: Cars,  Prev: Controls,  Up: Top

Dashboard
=========

Several rows of text are printed along the bottom of the screen to
provide some information about the car, similar to the gauges on a
car's dashboard.  You also get some information that you would not
normally see on a dashboard.  Here's what is shown, going down the
columns, starting on the left.

RPM
     The engine speed in revolutions per minute.

Torque
     The current engine torque in Newton-meters.

Speed
     The car's speed in kilometers per hour.

Gear
     The currently selected gear.  `N' stands for neutral and `R' is
     for reverse.

Slip Ratios
     The slip ratios for each of the tires.  A slip ratio is the
     difference between the speed of the contact patch and the road
     moving beneath it, divided by the speed of the wheel's hub.
     Rolling without sliding yields a slip ratio of zero.  Locking the
     wheels results in a slip ratio of 1.  Slip ratios are useful for
     seeing how close you are to the limit of adhesion.  A slip ratio
     of 0.1 is usually close to optimal.

Fuel
     Amount of fuel remaining in liters.

Lap Time
     The elapsed time for the current lap.

Last
     The time taken to complete the previous lap and the difference
     between this time and the best time.

Best
     The shortest lap time so far.

frame/s
     The current frame rate.

Sector
     The number of the current timing sector and the elapsed time for
     that sector.

Best
     The best time for the current sector.

Last Sector
     The time taken to complete the previous sector and the difference
     between this time and the best time for that sector.

Distance
     The distance from the start/finish line in meters.


File: vamos.info,  Node: Cars,  Next: Tracks,  Prev: Dashboard,  Up: Top

Cars
====

A number of different car definitions are provided.  The car can be
selected with `-c <car>' or `--car=<car>', where `<car>' is one of the
following

`F1'
     A modern Formula One car.

`F1-1967'
     A late sixties Formula One car.

`front-drive'
     A front wheel drive car.

`GT'
`default-car'
     A rear wheel drive sports car.

`trainer'
     An under-powered car for beginners.

Car File Format
===============

The car definition goes inside a `car' tag.  You can assign a name to
the car with the `name' attribute.

     <car name="GT">
       ...
     </car>

   The sections below show how the various subsystems are defined.

View
----

The driver's point-of-view is set with the `position' tag.  You may use
whatever units you like, as long as you're consistent.  *Note Units::.
The horizontal field-of-view is set with the `field-width' tag.  The
vertical field-of-view is calculated automatically from the current
window geometry.

       <view>
         <position>[ 1.3, 1.0, 0.8 ]</position>
         <field-width>60.0</field-width>
       </view>

Steering
--------

The maximum steering angle is set with the `max-angle' tag.  The
`exponent' detemines how linear the steering response is.  A higher
number makes the steering less sensitive at small angles.

       <steering>
         <max-angle>10.0</max-angle>
     	<exponent>3.0</exponent>
       </steering>

Drivetrain
----------

The drivetrain section defines the engine, clutch, transmission and
differential.

       <drivetrain>
         <engine>
           ...
         </engine>
     
         <clutch>
           ...
         </clutch>
     
         <transmission>
           ...
         </transmission>
     
         <differential>
           ...
         </differential>
       </drivetrain>

   The subsections of the drivetrain are described below.

         <engine>
     	  <position>[ 1.5, 1.0, 0.2 ]</position>
     	  <mass>200.0</mass>
           <max-power>3.0e5</max-power>
     	  <peak-engine-rpm>8000.0</peak-engine-rpm>
     	  <rpm-limit>10000.0</rpm-limit>
     	  <inertia>0.10</inertia>
     	  <idle>0.05</idle>
     	  <start-rpm>1000</start-rpm>
     	  <stall-rpm>500</stall-rpm>
     	  <fuel-consumption>0.0001</fuel-consumption>
     
           <sound>
             <file>engine.wav</file>
     		<pitch>0.01</pitch>
     		<volume>0.8</volume>
     		<throttle-volume-factor>1.0</throttle-volume-factor>
     		<engine-speed-volume-factor>0.001</engine-speed-volume-factor>
     	  </sound>
         </engine>

   The `position' and `mass' parameters affect the weight distribution
of the car.  The torque curve is calculated from `max-power' and
`peak-engine-rpm' using a polynomial expression given in `Motor Vehicle
Dynamics, Genta (1997)', where `peak-engine-rpm' is the engine speed at
which the maximum power output (`max-power') is achieved.  A rev limit
can be set with `rpm-limit'.  The rotational inertia of the moving
parts is `inertia'.  `idle' is the throttle position at idle.  Starting
the engine initially sets the engine speed to `start-rpm'.  Letting the
engine speed drop below `stall-rpm' makes the engine stall.  The rate
of fuel consumption is set with `fuel-consumption'.

   The engine sound is set in the `sound' section.  `file' is the name
of a WAV file in the `data/sounds' directory.  `throttle-volume-factor'
and `engine-speed-volume-factor' determine how the loudness of the
sound changes.

         <clutch>
           <sliding>0.5</sliding>
     	  <radius>0.25</radius>
     	  <area>0.2</area>
     	  <max-pressure>1.0e4</max-pressure>
         </clutch>

   The torque on the clutch is found by dividing the clutch pressure by
the value in the `area' tag and multiplying by the `radius' and
`sliding' (friction) parameters.

   The gear ratios can be defined in two different ways inside the
`transmission' tag.  The ratios can be defined individually as in the
example below.  The first number inside the brackets is the gear (-1 is
reverse), and the second is the clutch speed divided by the driveshaft
speed.

         <transmission>
     	  <gear-ratio>[ -1, -2.69 ]</gear-ratio>
     	  <gear-ratio>[ 1, 2.53 ]</gear-ratio>
     	  <gear-ratio>[ 2, 1.71 ]</gear-ratio>
     	  <gear-ratio>[ 3, 1.42 ]</gear-ratio>
     	  <gear-ratio>[ 4, 1.19 ]</gear-ratio>
     	  <gear-ratio>[ 5, 1.04 ]</gear-ratio>
     	  <shift-delay>0.2</shift-delay>
         </transmission>

   Alternatively, the number of gears and the highest and lowest ratios
can be specified.   The other gears will be calculate such that the
reciprocals of the ratios are equally spaced.

         <transmission>
     	  <forward-gears>5</forward-gears>
     	  <first-ratio>3.21</first-ratio>
     	  <last-ratio>1.10</last-ratio>
     	  <shift-delay>0.2</shift-delay>
         </transmission>

   The `shift-delay' tag tells how long it takes to change gears.  For
a paddle-shifter, like a modern Formula One car, `shift-delay' can be
set to zero.

Fuel Tank
---------

The fuel tank's position, the current volume of fuel and the density of
the fuel affect the car's weight distribution.  The `capacity' tag sets
the maximum volume of fuel that the tank can hold.  The initial volume
is set with the `volume' tag.  The density of the fuel is set with
`fuel-density'.

       <fuel-tank>
         <position>[ 1.00, 1.00, 0.25 ]</position>
     	<capacity>100.0</capacity>
     	<volume>100.0</volume>
     	<fuel-density>0.8</fuel-density>
       </fuel-tank>

Wheels
------

The `wheel' section contains information about the suspension, tire,
and brakes as well as the wheel itself.  The `side' and `end'
attributes tell where the wheel is located.  The values of these
attributes are important.

   The `steered' tag tells that the wheel responds to steering input.
The `driven' tag tells that torque from the engine is applied to the
wheel.  Only two wheels may have a `steered' tag, and only two may have
a `driven' tag.

       <wheel side="right" end="front">
         <steered/>
         <driven/>
         <position>[ 3.0, 0.05, -0.1 ]</position>
     	<mass>30.0</mass>
     	<restitution>0.1</restitution>
         <suspension>
           ...
         </suspension>
         <tire>
           ...
         </tire>
         <brakes>
           ...
         </brakes>
       <wheel>

   Values set in one wheel section are persistent; if you want the same
value for another wheel, you do not need set it.

   The suspension, tire, and brakes sections are described below.

Suspension
----------

         <suspension>
     	  <position>[ 3.0, 0.35, -0.1 ]</position>
     	  <hinge>[ 2.0, 0.35, 0.3 ]</hinge>
     	  <spring-constant>22000.0</spring-constant>
     	  <bounce>2000.0</bounce>
     	  <rebound>2000.0</rebound>
     	  <travel>0.4</travel>
     	  <max-compression-velocity>10.0</max-compression-velocity>
     	  <camber>-2.0</camber>
     	  <caster>5.0</caster>
     	  <toe>-2.0</toe>
     	</suspension>

The `hinge' is the center of the wheel's path as the suspension moves.
The location of the hinge is determined by suspension geometry, and may
be outside of the car itself.  Currently, this parameter has no effect
of performance.  It may be used in the future for configuring anti-dive
and anti-squat suspension geometries.

   `bounce' and `rebound' are the damping coefficients for compression
and expansion of the suspension, respectively.  If the speed at which
the suspension is compressed, or expanded exceeds the value in
`max-compression-velocity', the dampers "lock up."

   Wheel alignment is set with the `camber', `caster', and `toe' tags.
All angles are in degrees.

Tires
-----

The `longitudinal', `transverse', and `aligning' section each contain a
vector of "magic formula" coefficients as presented in `Motor Vehicle
Dynamics, Genta (1997)'.  The two elements of `rolling-resistance' are
the constant and velocity-squared terms, respectively.

     	<tire>
           <friction>
             <longitudinal>
               [ 1.65, 0.0, 1690.0, 0.0, 229.0, 0.0, 0.0, 0.0, -10.0, 0.0, 0.0 ]
             </longitudinal>
     	    <transverse>
     	      [ 1.80, 0.0, 1690.0, 800.0, 6.03, 0.0, -0.359, 1.0, 0.0, -6.11e-3, -3.22e-2, 0.0, 0.0, 0.0, 0.0 ]
     	    </transverse>
     	    <aligning>
     	      [ 2.07, -6.49, -21.9, 0.416, -21.3, 2.94e-2, 0.0, -1.20, 5.23, -14.8, 0.0, 0.0, -3.74e-3, 3.89e-2, 0.0, 0.0, 0.639, 1.69 ]
     	    </aligning>
     	  </friction>
     	  <radius>0.310</radius>
           <rolling-resistance>[ 1.3e-2, 6.5e-6 ]</rolling-resistance>
     	  <rotational-inertia>10.0</rotational-inertia>
         </tire>

Brakes
------

         <brakes>
     	  <friction>0.8</friction>
     	  <max-pressure>2.0e6</max-pressure>
           <front-bias>0.55</front-bias>
     	  <radius>0.2</radius>
     	  <area>0.01</area>
         </brakes>

`front-bias' is the fraction of braking pressure applied to the front
brakes.

Particles and Contact Points
----------------------------

Particles affect the mass distribution of the car.

       <particle>
         <position>[ 2.0, 1.0, 0.5 ]</position>
     	<mass>100.0</mass>
       </particle>

   Contact points are particles that participate in collisions.  The
material specified in the `material' tag (either "metal" or "rubber")
determines the sound made when contact is detected.  The coefficients
of friction and restitution are set with the `friction' and
`restitution' tags, respectively.

       <contact-point>
         <mass>40.0</mass>
         <position>[ 0.0, 0.0, 0.0 ]</position>
     	<material>metal</material>
     	<friction>0.5</friction>
     	<restitution>0.1</restitution>
       </contact-point>

Drag and Wings
--------------

The aerodynamic properties of the car are determined by the `drag' and
`wing' sections.  The frontal area and coefficient of drag, set it
`frontal-area' and `drag-coefficient', are used to calculate the drag
force.

       <drag>
         <position>[ 2.0, 1.0, 0.25 ]</position>
     	<frontal-area>2.0</frontal-area>
     	<drag-coefficient>0.3</drag-coefficient>
       </drag>

   Downforce can be added with wings.  The amount of downforce is
determined by the value in the `lift-coefficient' tag.  If the lift
coefficient is positive, upforce is generated.  This is usually
undesirable for cars.  The `efficiency' determines how much drag is
added as downforce increases.  The `surface-area' is the surface area
of the wing.  This value is also used in the drag calculation.

       <wing>
         <position>[ 0.0, 0.9, 0.5 ]</position>
     	<frontal-area>0.2</frontal-area>
     	<drag-coefficient>0.0</drag-coefficient>
     	<surface-area>0.5</surface-area>
     	<lift-coefficient>-4.0</lift-coefficient>
     	<efficiency>0.95</efficiency>
       </wing>


File: vamos.info,  Node: Tracks,  Next: Worlds,  Prev: Cars,  Up: Top

Tracks
======

Once you get bored with the default, you might want to try driving on
some different tracks.  The track can be selected using command line
arguments.  Use either `vamos -t <track>' or `vamos --track==<track>',
where `<track>', is one of the following

`drag'
     A striaight flat strip of road.

`Indianapolis'
     The Indianapolis Motor Speedway's road course.

`jump'
     A striaight strip of road with a jump.

`Magny-Cours'
     The track for the French grand prix (2003).

`Monza'
     The high-speed Italian circuit (2003).

`Mosport'
     The former home of the Canadian grand prix.

`Nurburgring'
     The new Nurburgring in Germany (2003).

`Peanut'
`default-track'
     A simple track.

`Silverstone'
     The home of the British grand prix (2003).

`skid_pad'
     A cirular track for testing handling.

`Spa'
     The Spa-Francorchamps track in Belgium.

`Suzuka'
     The track for the Japanase grand prix.

   You can use the `trk-convert' program to turn a track file for RARS
(Robot Auto Racing <http://rars.sourceforge.net>) into a C++ track file
for Vamos.  The converted files usually need some adjusting, so you'll
have to learn a little about Vamos track files.

Track File Format
=================

Tracks are defined in XML files.  Here's the beginning of a track file.

     <track name="Peanut">
       <!-- Material Properties -->
     
       <sky>
         <sides>textures/sky_sides.png</sides>
     	<top>textures/sky_top.png</top>
     	<bottom>textures/sky_bottom.png</bottom>
     	<smooth/>
       </sky>

The Sky Box
-----------

All information goes inside the `track' tag.  The `sky' section
describes the sky box, which is a cube onto which a background is
mapped.  The `sides' image is wrapped around the front, right, back,
and left sides of the sky box.  The optional `smooth' tag can improve
the quality of the sky box images.

Materials
---------

After the sky box, the properties of the various materials that make up
the track are defined.

       <material name="track" type="asphalt">
     	<friction>1.0</friction>
     	<restitution>0.1</restitution>
     	<rolling>1.0</rolling>
     	<drag>0.0</drag>
     	<bump-amplitude>0.01</bump-amplitude>
     	<bump-wavelength>100.0</bump-wavelength>
     	<texture>
     	  <file>textures/track2.png</file>
     	  <length>200.0</length>
     	  <smooth/>
     	  <mipmap/>
     	</texture>
       </material>

   The name is used to identify the material in other parts of the file.
The type helps determine what sound is played.  The type must be one of
rubber, metal, asphalt, concrete, grass, gravel, or dirt.

   The `friction' tag sets the relative friction of the surface.  If,
for example, you want to specify another surface that has half the
friction of asphalt, you whould set the friction value to 0.5.  The
calculation of the actual frictional force involves the car.
Similarly, relative values of the coefficient of restitution, rolling
resistance, and velocity-dependent drag are set with the `restitution',
`rolling', and `drag' tags.

   The bumpiness of the surface is set with the `bump-amplitude', and
`bump-wavelength' tags.  They define a sinusiodal variation in the
track's elevation.  You may use whatever units you like, as long as
you're consistent.  *Note Units::.

   The texture image is set in the `texture' section.  The file is the
name of a PNG image file.  The physical size that the image covers is
set with the `length' and `width' tags.  In this example, the `width'
tag is omitted.   As a result, the texture is stretched to fit the
width of the track.

   The `smooth' and `mipmap' tags improve the quality of the images,
but they also reduce the frame rate.

Segments
--------

The materials are grouped into "segments" that describe the materials
for the track, kerbs, shoulders, and barriers.

       <segment name="left turn">
         [ wall grass kerb track kerb gravel tires ]
       </segment>

   The name is used to identify the segment in other parts of the file.
Inside the `segment' tag is an array of material names.  The material
of the right-side barrier (as seen from a car traveling forward around
the track) is first.

Track Geometry
--------------

The track is made up of `road' sections.  Here is a simple `road'
section

       <road segment="left turn">
         <resolution>5.0</resolution>
     	<length>130.0</length>
     	<radius>160.0</radius>
       </road>

   The `segment' attribute names a list of materials defined earlier in
the file.  The `resolution' sets the size of the quadrilateral
divisions in the road section.  The smaller the resolution, the more
closely the section approximates a smooth curve.  The length and width
are given in meters.  However, any system of units can be used as long
as they are used consistently throughout the simulation for both
derived and fundamental quantities.

   The first road section must set the width of the track and shoulder,
and also the height of the barriers.  These dimensions are specified as
(distance, width) pairs.  Any number of pairs may be specified for a
given width,  the program will interpolate linearly between specified
points.

       <!-- front straight -->
       <road segment="straight pit">
         <resolution>10.0</resolution>
     	<length>100.0</length>
     	<left-width>[ 0.0, 25.0 ]</left-width>
     	<right-width>[ 0.0, 25.0 ]</right-width>
     	<left-road-width>[ 0.0, 8.0 ]</left-road-width>
     	<right-road-width>[ 0.0, 8.0 ]</right-road-width>
     	<left-wall-height>2.0</left-wall-height>
     	<right-wall-height>2.0</right-wall-height>
     	<elevation>[ 20.0, 0.0 ]</elevation>
     	<elevation>[ 200.0, 5.0 ]</elevation>
       </road>

   Similarly, any number of elevation points may be specified.  A spline
is used to interpolate between elevation points to achieve smooth
elevation changes.

Braking Markers
---------------

Braking markers are signs that show the distance to an upcoming turn.
For turns approached a high speed, markers at 150 m, 100 m, and 50 m
are typically shown.

       <road>
         ...
     	<braking-marker>
     	  <file>textures/50.png</file>
     	  <distance>50.0</distance>
     	  <size>[ 1.4, 0.7 ]</size>
     	  <offset>[ 2.0, 0.0 ]</offset>
     	  <side>right</side>
     	</braking-marker>
     	<braking-marker>
     	  <file>textures/100.png</file>
     	  <distance>100.0</distance>
     	</braking-marker>
     	<braking-marker>
     	  <file>textures/150.png</file>
     	  <distance>150.0</distance>
     	</braking-marker>
         ...
       </road>

   Once the size and offset parameters have been set, they do not need
to be specified again unless you want to use different values.

Kerbs
-----

Concrete kerbs are often placed along the insides of curves, and on the
opposite side at the curve exits.  I'm not really sure why.
Nonetheless, kerbs can be specified in the road sections.

       <road>
         ...
     	<left-kerb>
     	  <start>
             <distance>10.0</distance>
     		<transition>
     		  <length>4.0</length>
     		  <width>1.0</width>
     		</transition>
     	  </start>
     	  <end>
             <distance>100.0</distance>
     		<transition>
     		  <length>4.0</length>
     		  <width>1.0</width>
     		</transition>
     	  </end>
     	  <profile>[ 1.0, 0.1 ][ 3.0, 0.1 ][ 3.1, 0.0 ]</profile>
     	</left-kerb>
     
         <right-kerb>
           ...
         </right-kerb>
         ...
       </road>

   Each road section can have a left-side and a right-side kerb.  A set
of coordinates of the form [ distance-from-edge-of-track,
elevation-above-track ] set the shape of the kerb in the `profile' tag.
A [ 0.0, 0.0 ] coordinate is inserted automatically.

   The `start' and `end' tags tell where and how the kerb begins and
ends.  The distance is relative to the beginning of the road section.
The `transition' section tells how the ends of the kerb are capped.  In
the example above, the kerb tapers down track level and a width of 1.0
m in a distance of 4.0 m.

   Once the transition length and width, and the profile are set they do
not need to be specified again unless you want to use different values.
You can use `<transition/>' to specify a transition with the
previously set values.  For example, this kerb runs the entire length
of its road section and is capped with transitions at both ends.

         <right-kerb>
     	  <start><transition/></start>
     	  <end><transition/></end>
         </right-kerb>

   If there's no `start' tag, the kerb starts at the beginning of the
road section with no transition.  If there's to `end', the kerb ends at
the end of the road section.  To make the kerb join smoothly across two
road sections, omit the `end' in the first section, and omit the
`start' in the second.

   Kerbs are typically serrated.  Again, I don't know why.  This can be
simulated by setting the bump parameters on the kerb material defined
near the beginning of the track file.


File: vamos.info,  Node: Worlds,  Next: Units,  Prev: Tracks,  Up: Top

Worlds
======

The "world" specifies various environmental factors.  Here's the entire
default world file.

     <world name="Earth">
       <!-- Acceleration due to gravity -->
       <gravity>9.8</gravity>
     
       <maximum-time-step>0.01</maximum-time-step>
     
       <atmosphere>
         <!-- Air density -->
     	<density>1.2</density>
     	<!-- Wind velocity -->
         <velocity>[ 0.0, 0.0, 0.0 ]</velocity>
       </atmosphere>
     
       <lighting>
         <!-- Direction to the light source -->
         <source-position>[ 0.0, -1.0, 1.0 ]</source-position>
     	<!-- RGB for ambient light -->
     	<ambient>[ 0.7 , 0.7, 0.7 ]</ambient>
       </lighting>
     </world>

   Here is a description of the sections.

`gravity'
     Acceleration due to gravity.  The typical value for Earth is 9.8
     m/s^2.

`maximum-time-step'
     Each frame in the simulation will be sub-divided into time steps no
     larger than this value.  If you see jitter when the car is stopped,
     try lowering the maximum time step.  However, you may take a
     performance hit, if the value is too small.

`atmosphere'
     Density of the air and wind velocity.

`lighting'
     Light source position and ambient light level.

   Other world files can be specified with the `--world=' or `-w'
options.  Just for fun, a world file for the moon is provided.


File: vamos.info,  Node: Units,  Next: Code Reference,  Prev: Worlds,  Up: Top

Units
*****

A number that describes a physical quantity is meaningless unless the
units of measure are given.  If we have a length of 20, we don't know
if it's 20 meters, 20 feet, or 20 light years.  Despite this fact,
there are no units specified in Vamos.

   Consider the fundamental quantities to be time, length, and mass.
From these, you can derive the units for any quantity used in the
simulation.  For instance, the units on velocity are a length unit
divided by a time unit.  Force units are mass times length divided by
time squared.  As long as the fundamental and derived units are
consistent, it does not matter what base units are used.

   There's one exception.  Since the simulation relies on library
functions for timing information, and these libraries use seconds, the
unit of time must be seconds.

   I always use SI (metric) units because it's easy to keep the base and
derived units consistent.  The SI base units are the meter (m) for
length and kilogram (kg) for mass.  Power is derived quantity with
units of Watts.  A Watt is a kg*m^2/s^3.  If you use feet and slugs as
your base unit, then your power will be in slug*ft^2/s^3; you can't
simply use horsepower.

   Derived units used in the simulation are

   * area (distance^2)

   * volume (distance^3)

   * speed (distance/time)

   * acceleration (distance/time^2)

   * force (mass*acceleration)

   * torque (force*distance)

   * engine power (force*distance/time)

   * spring constant (force/distance)

   * damping (force/speed)

   * density (mass/volume)

   There are some places where non-SI units are used.  All angles are
specified in degrees.  Engine speeds are specified in rotations per
minute (RPM).  The coefficients for tire friction have their customary
units.


File: vamos.info,  Node: Code Reference,  Next: Building Vamos,  Prev: Units,  Up: Top

Code Reference
**************

The code is devided into four modules that reside in four namespaces,
`Vamos_Geometry', `Vamos_Body', `Vamos_Track' and `Vamos_World'.  Each
namespace contains the code for a library.  These libraries are
`libvamos-geometry', `libvamos-body', `libvamos-track', and
`libvamos-world'.  The geometry library has classes for vectors,
matrices and curves.  The body library has a class for a rigid body and
classes for a car and its parts.  It also has other classes that are
needed by more than one of the other libraries.  The track library has
the classes needed for building a track.  The world library handles a
rigid body's interaction with the track.

* Menu:

* The Geometry Library::        Vectors, matrices, curves, etc.
* The Track Library::           The driving surface.
* The Body Library::            Cars and other rigid bodies.
* The World Library::           The world mediates interactions.

   The geometry library is used by both the body and world libraries.
The body library is used by the world library.  The dependency graph
looks like this:
                libvamos-geometry
               /        |        \
             o          |          o
     libvamos-track     |      libvamos-body
             \          o         /
               o libvamos-world o
where
     libA o-- libB
means that library `libA' depends on library `libB'.  That is,
classes in `libA' include headers from `libB'.  Also a program that
links `libA' must also link `libB'.

   If you only need the services of the geometry library, then you only
have one library to link.  If you use the body library, then you need to
link the geometry library as well.  If you use the world library, then
you need to link all four.  When linking multiple libraries you may need
to make sure that `libvamos-geometry' is linked first, followed by
`libvamos-body', and then `libvamos-world'.  If you get errors from the
linker about undefined references to functions defined in one of these
libraries, then you may have to adjust the link order.

   Care was taken to avoid a dependency of `libvamos-track' on
`libvamos-body' and vice versa.  This allows cars and tracks to tested
independently.


File: vamos.info,  Node: The Geometry Library,  Next: The Track Library,  Up: Code Reference

The Geometry Library
====================

The geometry module is a collection of generic geometric objects.  Also,
classes that are required by more than one other module.  This is done
to avoid dependency problems.

Three_Vector
============

A `Three_Vector' represents a vector in three-dimensions.  Some
supported operations are

   * subscripting using `[]'

   * vector addition and subtraction using `+' and `-'

   * multiplication and division by a scalar using `*' and `/'

   * left and right matrix multiplication using `*'

   * dot and cross products using the `dot()' and `cross()'methods

   * projection onto another vector using the `project()' method

   * magnitude using the `abs()' method

   Matrix multiplication is done with a `Three_Matrix'.

Three_Matrix
============

A `Three_Matrix' represents 3x3 matrix.  It's suitable for representing
a three-dimensional rotation matrix or inertia tensor.  Some suported
operations are

   * subscripting using `[]'

   * matrix addition and subtraction using `+' and `-'

   * multiplication and division by a scalar using `*' and `/'

   * left and right vector multiplication using `*'

   * matrix multiplication using `*'

   * eigenvalue and eigenvector determination

   * inversion

Inertia_Tensor
==============

An inertia tensor is a matrix that describes a rigid body's responce to
torques.  The `Inertia_Tensor' generates the tensor from the locations
of masses on a body.  The masses and positions are specified using the
`add()' method.  The `inertia()' method returns the moment of inertia
for a force applied at a particular point on the body.

Two_Point
=========

A `Two_Point' describes a point in a plane.  It is a `struct' with two
data members, `x' and `y'.  A constructor is provided for initializing
the members.  No vector operations are supported, and some of the
supported operations are undefined for vectors.  That's why this class
is called `Two_Point' and not `Two_Vector'.  The supported operations
are scalar and member-wise addition, subtraction, multiplication, and
division.  For the scalar versions, the operation is performed on each
member.

   `Spline' is the only user of `Two_Point'.  Perhaps it should be
defined in `Spline''s header so that there's less temptation to use
`Two_Point' inappropriately.

Spline
======

`Spline' is a class for a parametric cubic spline interpolation between
points.  A vector of `Two_Point's through which the curve passes and
angle of the curve at the first and last points are passed to the
constructor.

   `Spline's are used to make smooth road elevation changes and banking
transitions.

Surface
=======

A `Surface' describes the friction, rolling resistance, restitution and
texture image of a surface such as pavement, grass or gravel.

Texture_Image
=============

The `Texture Image' class provides a convenient way of reading a
`*.ppm' image file from the disk and for getting information about the
image.

Conversions
===========

The header file `Conversions.h' contains a few functions for performing
frequently-used unit conversions.  Currently, there are conversions for
radians and degress, radians per second and revolutions per minute, and
meters per second and kilometers per hour.


File: vamos.info,  Node: The Track Library,  Next: The Body Library,  Prev: The Geometry Library,  Up: Code Reference

The Track Library
=================

A `Track' is a collection of straight and curved pieces of road.  These
pieces are described by classes derived from `Road_Segment'.
Currently, we have a straight segment class (`Straight_Road'), and a
circle arc segment class (`Arc_Road').  The track is assembled so that
there are no corners where two segments join.

   If you look at the code you'll find a class for a segment that
smoothly curves through a set of given points (`Spline_Road').  This
class has been commented out because I don't know how to do the
transformation from world coordinates to track coordinates for a spline.

   The elevation and banking at any number of points on a segment can be
specified.  The specified points are interpolated with a cubic spline so
that the transitions are smooth.

     Track o---Road_Segment
                ^     ^
               /       \
     Straight_Road    Arc_Road


File: vamos.info,  Node: The Body Library,  Next: The World Library,  Prev: The Track Library,  Up: Code Reference

The Body Library
================

A `Body' describes a three-dimensional rigid body made up of point
particles.  These particles are described by `Particle' and its
subclasses.  Position and orientation for both `Body's and `Particle's
is provided by the `Frame' base class.  The `Car' class is derived from
`Body'

          Frame
          ^   ^
         /     \
      Body o---Particle
       ^
       |
      Car

* Menu:

* Frame::                       A coordinate system.
* Particle::                    A body is made up of point particles.
* Body::                        A rigid body.
* Car::                         A drivable body.


File: vamos.info,  Node: Frame,  Next: Particle,  Up: The Body Library

Frame
-----


File: vamos.info,  Node: Particle,  Next: Body,  Prev: Frame,  Up: The Body Library

Particle
--------


File: vamos.info,  Node: Body,  Next: Car,  Prev: Particle,  Up: The Body Library

Body
----


File: vamos.info,  Node: Car,  Prev: Body,  Up: The Body Library

Car
---

Drivetrain
..........

Wheel
.....


File: vamos.info,  Node: The World Library,  Prev: The Body Library,  Up: Code Reference

The World Library
=================

To avoid dependencies, `Track', `Atmosphere', and `Body' were each
designed so that they know nothing about the others.  It is the purpose
of the `World' class to mediate any interactions among those classes.
Because `Track', `Atmosphere', and `Body' are independent, it is
neccessary that `World' depend on each of these classes.  A subclass of
`World' that provides an interface to the input methods of `Car' is
provided.  It's called `Car_World'.  (Apologies to Marcus Hewat,
creator of the Carworld program,
<http://perso.club-internet.fr/hewat/carworld/carworld.htm>.  Aside
from some bits of code I stole for reading textures from files and
drawing text on the screen, this project is unrelated to Carworld.)

             World
            o ^ o o---.
           /  |  \     \
      Track   |  Body  Atmosphere
              |   ^
       Car_World  |
               o  |
                \ |
                 Car

   The `World' base class doesn't do any graphics.  If you want to see
the results of the simulation on screen, you must derive an appropriate
class and define the `draw()' method.  An example of such a class that
uses OpenGL, `Gl_Car_World', is provided.  You must also use subclasses
of Track and Car (such as `Gl_Track' and `Gl_Car') that use the same
graphics system if you wish to see instances of those objects.

   A typical application will construct a `Track', `Atmosphere', and
`Car', and then construct a `World' by passing pointers to those
objects.  The simulation is started by calling the `World''s `start()'
method.  The `World' is responsible for initializing the graphics
system (if used) and starting the event loop.

Atmosphere
----------

To be written.


File: vamos.info,  Node: Building Vamos,  Next: Copying,  Prev: Code Reference,  Up: Top

Building Vamos
**************

Downloading
===========

You can get the latest release by going to the Vamos home page,
<http://vamos.sourceforge.net>, and following the "Download" link.
Another way to get there is to go through the SourceForge project page,
<http://sourceforge.net/projects/vamos>.

Dependencies
============

Vamos makes use of some external libraries.  These libraries need to be
present in order to compile Vamos.

   OpenGL-compatible libraries, including the OpenGL Utility Library
(GLU) and the OpenGL Utility Toolkit (GLUT) must be installed.  Mesa
<http://www.mesa-3d.org> works fine.  In addition, you need accelerated
video hardware.  Some video cards require specific GL implementations.

   For joystick control and sound, PLIB version 1.4 or later must be
present.  You can get it from <http://plib.sourceforge.net>.

   XML files are parsed with the help of SimGear.  Get version 0.2.0 or
later from <http://www.simgear.org>.

   Libsigc++ version 1.2 is used for implementing callbacks to member
functions.  Libsigc++ can be downloaded from
<http://libsigc.sourceforge.net>.

   You will also need a reasonably up-to-date C++ compiler.
Specifically, it must handle namespaces.  Gcc version 2.96 and later,
including 3.x, should do.  See <http://gcc.gnu.org>.

   By the way, the phrase "or later" does not mean that I can see into
the future.  I can't guarantee that a new version of one of these
packages will not be incompatible with Vamos.  If you find such an
incompatibility, please let me know.

Compiling
=========

After downloading the source archive (the `tar.gz' file), unpack it
with the `tar' command, or some other utility.  All of the files in the
archive are placed in a subdirectory.  If the archive is
`vamos-1.2.3.tar.gz', the files are placed in `vamos-1.2.3'.

   Vamos uses the GNU Autotools (`automake', `autoconf', and `libtool')
to check for prerequisites and handle different architectures.  Change
to the directory created by un-archiving and type `./configure'.  Type
`./configure --help' to see the options accepted by `configure'.  I
have only tried to compile Vamos on GNU/Linux and Cygwin/Win32
platforms.  Please write me if you find an architecture that is not
handled correctly.

   The `configure' script generates the `Makefile's needed to compile
the program.  Issue the `make' command to start the compilation.  If
you encounter errors, or warnings that you think I should know about,
please contact me.

   If the compilation succeeds, you can install the libraries, headers,
and application by typing `make install'.  You may need to be a
privileged user to install software on your system.  You do not need to
install the program to run the application.  Switch to the `vamos'
directory and run `./vamos' to try the application without installing.


File: vamos.info,  Node: Copying,  Next: Concept Index,  Prev: Building Vamos,  Up: Top

Copying
*******

Vamos may be copied according to the terms of the GNU General Public
License (GNU GPL).  The license is in the file COPYING in the top-level
directory of the source code.

   This documentation may be copied according to the terms of the GNU
Free Documentation License (GNU FDL) which is printed below.

GNU Free Documentation License
==============================

                        Version 1.1, March 2000
     Copyright (C) 2000 Free Software Foundation, Inc.
     59 Temple Place, Suite 330, Boston, MA  02111-1307, USA
     
     Everyone is permitted to copy and distribute verbatim copies
     of this license document, but changing it is not allowed.

  0. PREAMBLE

     The purpose of this License is to make a manual, textbook, or other
     written document "free" in the sense of freedom: to assure everyone
     the effective freedom to copy and redistribute it, with or without
     modifying it, either commercially or noncommercially.  Secondarily,
     this License preserves for the author and publisher a way to get
     credit for their work, while not being considered responsible for
     modifications made by others.

     This License is a kind of "copyleft", which means that derivative
     works of the document must themselves be free in the same sense.
     It complements the GNU General Public License, which is a copyleft
     license designed for free software.

     We have designed this License in order to use it for manuals for
     free software, because free software needs free documentation: a
     free program should come with manuals providing the same freedoms
     that the software does.  But this License is not limited to
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  1. APPLICABILITY AND DEFINITIONS

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     numbering more than 100, you must either include a
     machine-readable Transparent copy along with each Opaque copy, or
     state in or with each Opaque copy a publicly-accessible
     computer-network location containing a complete Transparent copy
     of the Document, free of added material, which the general
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     begin distribution of Opaque copies in quantity, to ensure that
     this Transparent copy will remain thus accessible at the stated
     location until at least one year after the last time you
     distribute an Opaque copy (directly or through your agents or
     retailers) of that edition to the public.

     It is requested, but not required, that you contact the authors of
     the Document well before redistributing any large number of
     copies, to give them a chance to provide you with an updated
     version of the Document.

  4. MODIFICATIONS

     You may copy and distribute a Modified Version of the Document
     under the conditions of sections 2 and 3 above, provided that you
     release the Modified Version under precisely this License, with
     the Modified Version filling the role of the Document, thus
     licensing distribution and modification of the Modified Version to
     whoever possesses a copy of it.  In addition, you must do these
     things in the Modified Version:

       A. Use in the Title Page (and on the covers, if any) a title
          distinct from that of the Document, and from those of
          previous versions (which should, if there were any, be listed
          in the History section of the Document).  You may use the
          same title as a previous version if the original publisher of
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       B. List on the Title Page, as authors, one or more persons or
          entities responsible for authorship of the modifications in
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          principal authors of the Document (all of its principal
          authors, if it has less than five).

       C. State on the Title page the name of the publisher of the
          Modified Version, as the publisher.

       D. Preserve all the copyright notices of the Document.

       E. Add an appropriate copyright notice for your modifications
          adjacent to the other copyright notices.

       F. Include, immediately after the copyright notices, a license
          notice giving the public permission to use the Modified
          Version under the terms of this License, in the form shown in
          the Addendum below.

       G. Preserve in that license notice the full lists of Invariant
          Sections and required Cover Texts given in the Document's
          license notice.

       H. Include an unaltered copy of this License.

       I. Preserve the section entitled "History", and its title, and
          add to it an item stating at least the title, year, new
          authors, and publisher of the Modified Version as given on
          the Title Page.  If there is no section entitled "History" in
          the Document, create one stating the title, year, authors,
          and publisher of the Document as given on its Title Page,
          then add an item describing the Modified Version as stated in
          the previous sentence.

       J. Preserve the network location, if any, given in the Document
          for public access to a Transparent copy of the Document, and
          likewise the network locations given in the Document for
          previous versions it was based on.  These may be placed in
          the "History" section.  You may omit a network location for a
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          it refers to gives permission.

       K. In any section entitled "Acknowledgments" or "Dedications",
          preserve the section's title, and preserve in the section all
          the substance and tone of each of the contributor
          acknowledgments and/or dedications given therein.

       L. Preserve all the Invariant Sections of the Document,
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          or the equivalent are not considered part of the section
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       M. Delete any section entitled "Endorsements".  Such a section
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       N. Do not retitle any existing section as "Endorsements" or to
          conflict in title with any Invariant Section.

     If the Modified Version includes new front-matter sections or
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     You may add a section entitled "Endorsements", provided it contains
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     You may add a passage of up to five words as a Front-Cover Text,
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  5. COMBINING DOCUMENTS

     You may combine the Document with other documents released under
     this License, under the terms defined in section 4 above for
     modified versions, provided that you include in the combination
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  6. COLLECTIONS OF DOCUMENTS

     You may make a collection consisting of the Document and other
     documents released under this License, and replace the individual
     copies of this License in the various documents with a single copy
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     this License in all other respects regarding verbatim copying of
     that document.

  7. AGGREGATION WITH INDEPENDENT WORKS

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     separate and independent documents or works, in or on a volume of
     a storage or distribution medium, does not as a whole count as a
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     copyright is claimed for the compilation.  Such a compilation is
     called an "aggregate", and this License does not apply to the
     other self-contained works thus compiled with the Document, on
     account of their being thus compiled, if they are not themselves
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     If the Cover Text requirement of section 3 is applicable to these
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  8. TRANSLATION

     Translation is considered a kind of modification, so you may
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     translations of some or all Invariant Sections in addition to the
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     original English version of this License.  In case of a
     disagreement between the translation and the original English
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  9. TERMINATION

     You may not copy, modify, sublicense, or distribute the Document
     except as expressly provided for under this License.  Any other
     attempt to copy, modify, sublicense or distribute the Document is
     void, and will automatically terminate your rights under this
     License.  However, parties who have received copies, or rights,
     from you under this License will not have their licenses
     terminated so long as such parties remain in full compliance.

 10. FUTURE REVISIONS OF THIS LICENSE

     The Free Software Foundation may publish new, revised versions of
     the GNU Free Documentation License from time to time.  Such new
     versions will be similar in spirit to the present version, but may
     differ in detail to address new problems or concerns.  See
     `http://www.gnu.org/copyleft/'.

     Each version of the License is given a distinguishing version
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     have the option of following the terms and conditions either of
     that specified version or of any later version that has been
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     the Document does not specify a version number of this License,
     you may choose any version ever published (not as a draft) by the
     Free Software Foundation.

ADDENDUM: How to use this License for your documents
----------------------------------------------------

To use this License in a document you have written, include a copy of
the License in the document and put the following copyright and license
notices just after the title page:

       Copyright (C)  YEAR  YOUR NAME.
       Permission is granted to copy, distribute and/or modify this document
       under the terms of the GNU Free Documentation License, Version 1.1
       or any later version published by the Free Software Foundation;
       with the Invariant Sections being LIST THEIR TITLES, with the
       Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.
       A copy of the license is included in the section entitled ``GNU
       Free Documentation License''.

   If you have no Invariant Sections, write "with no Invariant Sections"
instead of saying which ones are invariant.  If you have no Front-Cover
Texts, write "no Front-Cover Texts" instead of "Front-Cover Texts being
LIST"; likewise for Back-Cover Texts.

   If your document contains nontrivial examples of program code, we
recommend releasing these examples in parallel under your choice of
free software license, such as the GNU General Public License, to
permit their use in free software.


File: vamos.info,  Node: Concept Index,  Prev: Copying,  Up: Top

Concept Index
*************

* Menu:

* Atmosphere:                            The World Library.
* Body:                                  The Body Library.
* body library:                          The Body Library.
* building:                              Building Vamos.
* Car:                                   The Body Library.
* cars:                                  Cars.
* compiling:                             Building Vamos.
* configure:                             Building Vamos.
* controls:                              Controls.
* Conversions:                           The Geometry Library.
* copying:                               Copying.
* dashboard:                             Dashboard.
* dependencies:                          Building Vamos.
* downloading:                           Building Vamos.
* driving:                               Let's Go.
* FDL, GNU Free Documentation License:   Copying.
* Frame:                                 The Body Library.
* geometry library:                      The Geometry Library.
* image:                                 The Geometry Library.
* inertia tensor:                        The Geometry Library.
* Inertia_Tensor:                        The Geometry Library.
* installing:                            Building Vamos.
* libvamos-body:                         The Body Library.
* libvamos-geometry:                     The Geometry Library.
* libvamos-track:                        The Track Library.
* libvamos-world:                        The World Library.
* matrix:                                The Geometry Library.
* Particle:                              The Body Library.
* point:                                 The Geometry Library.
* Spline:                                The Geometry Library.
* spline:                                The Geometry Library.
* surface:                               The Geometry Library.
* texture:                               The Geometry Library.
* Texture_Image:                         The Geometry Library.
* Three_Matrix:                          The Geometry Library.
* Three_Vector:                          The Geometry Library.
* track library:                         The Track Library.
* tracks:                                Tracks.
* Two_Point:                             The Geometry Library.
* units:                                 Units.
* Vamos_Body:                            The Body Library.
* Vamos_Geometry:                        The Geometry Library.
* Vamos_Track:                           The Track Library.
* Vamos_World:                           The World Library.
* vector:                                The Geometry Library.
* world library:                         The World Library.



Tag Table:
Node: Top1232
Node: Let's Go2316
Node: Controls4840
Node: Dashboard10763
Node: Cars12529
Node: Tracks23396
Node: Worlds32460
Node: Units33901
Node: Code Reference35750
Node: The Geometry Library38053
Node: The Track Library41396
Node: The Body Library42436
Node: Frame43201
Node: Particle43288
Node: Body43394
Node: Car43490
Node: The World Library43603
Node: Building Vamos45428
Node: Copying48344
Node: Concept Index68533

End Tag Table
