This is the license which applies to OpenTTD with the exception of some

3rd party modules. See [./README.md](./README.md) for details

GNU General Public License

==========================

_Version 2, June 1991_

_Copyright © 1989, 1991 Free Software Foundation, Inc.,_

_51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA_

Everyone is permitted to copy and distribute verbatim copies

of this license document, but changing it is not allowed.

### Preamble

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software--to make sure the software is free for all its users.  This

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When we speak of free software, we are referring to freedom, not

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To protect your rights, we need to make restrictions that forbid

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### TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION

**0.** This License applies to any program or other work which contains

a notice placed by the copyright holder saying it may be distributed

under the terms of this General Public License.  The "Program", below,

refers to any such program or work, and a "work based on the Program"

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is covered only if its contents constitute a work based on the

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Whether that is true depends on what the Program does.

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You may charge a fee for the physical act of transferring a copy, and

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These requirements apply to the modified work as a whole.  If

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In addition, mere aggregation of another work not based on the Program

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### NO WARRANTY

**11.** BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY

FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN

OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES

PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED

OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF

MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS

TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE

PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,

REPAIR OR CORRECTION.

**12.** IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING

WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR

REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,

INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING

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END OF TERMS AND CONDITIONS

### How to Apply These Terms to Your New Programs

If you develop a new program, and you want it to be of the greatest

possible use to the public, the best way to achieve this is to make it

free software which everyone can redistribute and change under these terms.

To do so, attach the following notices to the program.  It is safest

to attach them to the start of each source file to most effectively

convey the exclusion of warranty; and each file should have at least

the "copyright" line and a pointer to where the full notice is found.

    <one line to give the program's name and a brief idea of what it does.>

    Copyright (C) <year>  <name of author>

    This program is free software; you can redistribute it and/or modify

    it under the terms of the GNU General Public License as published by

    the Free Software Foundation; either version 2 of the License, or

    (at your option) any later version.

    This program is distributed in the hope that it will be useful,

    but WITHOUT ANY WARRANTY; without even the implied warranty of

    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License along

    with this program; if not, write to the Free Software Foundation, Inc.,

    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

Also add information on how to contact you by electronic and paper mail.

If the program is interactive, make it output a short notice like this

when it starts in an interactive mode:

    Gnomovision version 69, Copyright (C) year name of author

    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.

    This is free software, and you are welcome to redistribute it

    under certain conditions; type `show c' for details.

The hypothetical commands `show w` and `show c` should show the appropriate

parts of the General Public License.  Of course, the commands you use may

be called something other than `show w` and `show c`; they could even be

mouse-clicks or menu items--whatever suits your program.

You should also get your employer (if you work as a programmer) or your

school, if any, to sign a "copyright disclaimer" for the program, if

necessary.  Here is a sample; alter the names:

    Yoyodyne, Inc., hereby disclaims all copyright interest in the program

    `Gnomovision' (which makes passes at compilers) written by James Hacker.

    <signature of Ty Coon>, 1 April 1989

    Ty Coon, President of Vice

This General Public License does not permit incorporating your program into

proprietary programs.  If your program is a subroutine library, you may

consider it more useful to permit linking proprietary applications with the

library.  If this is what you want to do, use the GNU Lesser General

Public License instead of this License.

# OpenTTD

## Table of contents

- 1.0) [About](#10-about)

    - 1.1) [Downloading OpenTTD](#11-downloading-openttd)

    - 1.2) [OpenTTD gameplay manual](#12-openttd-gameplay-manual)

    - 1.3) [Supported platforms](#13-supported-platforms)

    - 1.4) [Installing and running OpenTTD](#14-installing-and-running-openttd)

    - 1.5) [Add-on content / mods](#15-add-on-content--mods)

    - 1.6) [OpenTTD directories](#16-openttd-directories)

    - 1.7) [Compiling OpenTTD](#17-compiling-openttd)

- 2.0) [Contact and community](#20-contact-and-community)

    - 2.1) [Contributing to OpenTTD](#21-contributing-to-openttd)

    - 2.2) [Reporting bugs](#22-reporting-bugs)

    - 2.3) [Translating](#23-translating)

- 3.0) [Licensing](#30-licensing)

- 4.0) [Credits](#40-credits)

## 1.0) About

OpenTTD is a transport simulation game based upon the popular game Transport Tycoon Deluxe, written by Chris Sawyer.

It attempts to mimic the original game as closely as possible while extending it with new features.

OpenTTD is licensed under the GNU General Public License version 2.0, but includes some 3rd party software under different licenses.

See the section ["Licensing"](#30-licensing) below for details.

## 1.1) Downloading OpenTTD

OpenTTD can be downloaded from the [official OpenTTD website](https://www.openttd.org/).

Both 'stable' and 'nightly' versions are available for download:

- most people should choose the 'stable' version, as this has been more extensively tested

- the 'nightly' version includes the latest changes and features, but may sometimes be less reliable

OpenTTD is also available for free on [Steam](https://store.steampowered.com/app/1536610/OpenTTD/), [GOG.com](https://www.gog.com/game/openttd), and the [Microsoft Store](https://www.microsoft.com/p/openttd-official/9ncjg5rvrr1c). On some platforms OpenTTD will be available via your OS package manager or a similar service.

## 1.2) OpenTTD gameplay manual

OpenTTD has a [community-maintained wiki](https://wiki.openttd.org/), including a gameplay manual and tips.

## 1.3) Supported platforms

OpenTTD has been ported to several platforms and operating systems.

The currently supported platforms are:

- Linux (SDL (OpenGL and non-OpenGL))

- macOS (universal) (Cocoa)

- Windows (Win32 GDI / OpenGL)

Other platforms may also work (in particular various BSD systems), but we don't actively test or maintain these.

### 1.3.1) Legacy support

Platforms, languages and compilers change.

We'll keep support going on old platforms as long as someone is interested in supporting them, except where it means the project can't move forward to keep up with language and compiler features.

We guarantee that every revision of OpenTTD will be able to load savegames from every older revision (excepting where the savegame is corrupt).

Please report a bug if you find a save that doesn't load.

## 1.4) Installing and running OpenTTD

OpenTTD is usually straightforward to install, but for more help the wiki [includes an installation guide](https://wiki.openttd.org/en/Manual/Installation).

OpenTTD needs some additional graphics and sound files to run.

For some platforms these will be downloaded during the installation process if required.

For some platforms, you will need to refer to [the installation guide](https://wiki.openttd.org/en/Manual/Installation).

### 1.4.1) Free graphics and sound files

The free data files, split into OpenGFX for graphics, OpenSFX for sounds and

OpenMSX for music can be found at:

- https://www.openttd.org/downloads/opengfx-releases/ for OpenGFX

- https://www.openttd.org/downloads/opensfx-releases/ for OpenSFX

- https://www.openttd.org/downloads/openmsx-releases/ for OpenMSX

Please follow the readme of these packages about the installation procedure.

The Windows installer can optionally download and install these packages.

### 1.4.2) Original Transport Tycoon Deluxe graphics and sound files

If you want to play with the original Transport Tycoon Deluxe data files you have to copy the data files from the CD-ROM into the baseset/ directory.

It does not matter whether you copy them from the DOS or Windows version of Transport Tycoon Deluxe.

The Windows install can optionally copy these files.

You need to copy the following files:

- sample.cat

- trg1r.grf or TRG1.GRF

- trgcr.grf or TRGC.GRF

- trghr.grf or TRGH.GRF

- trgir.grf or TRGI.GRF

- trgtr.grf or TRGT.GRF

### 1.4.3) Original Transport Tycoon Deluxe music

If you want the Transport Tycoon Deluxe music, copy the appropriate files from the original game into the baseset folder.

- TTD for Windows: All files in the gm/ folder (gm_tt00.gm up to gm_tt21.gm)

- TTD for DOS: The GM.CAT file

- Transport Tycoon Original: The GM.CAT file, but rename it to GM-TTO.CAT

## 1.5) Add-on content / mods

OpenTTD features multiple types of add-on content, which modify gameplay in different ways.

Most types of add-on content can be downloaded within OpenTTD via the 'Check Online Content' button in the main menu.

Add-on content can also be installed manually, but that's more complicated; the [OpenTTD wiki](https://wiki.openttd.org/) may offer help with that, or the [OpenTTD directory structure guide](./docs/directory_structure.md).

### 1.5.1) AI opponents

OpenTTD comes without AI opponents, so if you want to play with AIs you have to download them.

The easiest way is via the 'Check Online Content' button in the main menu.

You can select some AIs that you think are compatible with your playing style.

AI help and discussions may also be found in the [AI section of the forum](https://www.tt-forums.net/viewforum.php?f=65).

### 1.5.2) Scenarios and height maps

Scenarios and heightmaps can be added via the 'Check Online Content' button in the main menu.

### 1.5.3) NewGRFs

A wide range of add-content is available as NewGRFs, including vehicles, industries, stations, landscape objects, town names and more.

NewGRFs can be added via the 'Check Online Content' button in the main menu.

See also the wiki [guide to NewGRFs](https://wiki.openttd.org/en/Manual/NewGRF) and [the forum graphics development section](https://www.tt-forums.net/viewforum.php?f=66).

### 1.5.4) Game scripts

Game scripts can provide additional challenges or changes to the standard OpenTTD gameplay, for example setting transport goals, or changing town growth behaviour.

Game scripts can be added via the 'Check Online Content' button in the main menu.

See also the wiki [guide to game scripts](https://wiki.openttd.org/en/Manual/Game%20script) and [the forum graphics game script section](https://www.tt-forums.net/viewforum.php?f=65).

### 1.6) OpenTTD directories

OpenTTD uses its own directory structure to store game data, add-on content etc.

For more information, see the [directory structure guide](./docs/directory_structure.md).

### 1.7) Compiling OpenTTD

If you want to compile OpenTTD from source, instructions can be found in [COMPILING.md](./COMPILING.md).

## 2.0) Contact and Community

'Official' channels

- [OpenTTD website](https://www.openttd.org)

- IRC chat using #openttd on irc.oftc.net [more info about our irc channel](https://wiki.openttd.org/en/Development/IRC%20channel)

- [OpenTTD on Github](https://github.com/openTTD/) for code repositories and for reporting issues

- [forum.openttd.org](https://forum.openttd.org/) - the primary community forum site for discussing OpenTTD and related games

- [OpenTTD wiki](https://wiki.openttd.org/) community-maintained wiki, including topics like gameplay guide, detailed explanation of some game mechanics, how to use add-on content (mods) and much more

'Unofficial' channels

- the OpenTTD wiki has a [page listing OpenTTD communities](https://wiki.openttd.org/en/Community/Community) including some in languages other than English

### 2.1) Contributing to OpenTTD

We welcome contributors to OpenTTD.  More information for contributors can be found in [CONTRIBUTING.md](./CONTRIBUTING.md)

### 2.2) Reporting bugs

Good bug reports are very helpful.  We have a [guide to reporting bugs](./CONTRIBUTING.md#bug-reports) to help with this.

Desyncs in multiplayer are complex to debug and report (some software development skils are required).

Instructions can be found in [debugging and reporting desyncs](./docs/debugging_desyncs.md).

### 2.3) Translating

OpenTTD is translated into many languages.  Translations are added and updated via the [online translation tool](https://translator.openttd.org).

## 3.0) Licensing

OpenTTD is licensed under the GNU General Public License version 2.0.

For the complete license text, see the file '[COPYING.md](./COPYING.md)'.

This license applies to all files in this distribution, except as noted below.

The squirrel implementation in `src/3rdparty/squirrel` is licensed under the Zlib license.

See `src/3rdparty/squirrel/COPYRIGHT` for the complete license text.

The md5 implementation in `src/3rdparty/md5` is licensed under the Zlib license.

See the comments in the source files in `src/3rdparty/md5` for the complete license text.

The implementations of Posix `getaddrinfo` and `getnameinfo` for OS/2 in `src/3rdparty/os2` are distributed partly under the GNU Lesser General Public License 2.1, and partly under the (3-clause) BSD license.

The exact licensing terms can be found in `src/3rdparty/os2/getaddrinfo.c` resp. `src/3rdparty/os2/getnameinfo.c`.

The fmt implementation in `src/3rdparty/fmt` is licensed under the MIT license.

See `src/3rdparty/fmt/LICENSE.rst` for the complete license text.

## 4.0 Credits

See [CREDITS.md](./CREDITS.md)

/*

 * This file is part of OpenTTD.

 * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.

 * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

 * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.

 */

AILog.Info("0.7 API compatibility in effect:");

AILog.Info(" - AITown::GetLastMonthProduction's behaviour has slightly changed.");

AILog.Info(" - AISubsidy::GetDestination returns STATION_INVALID for awarded subsidies.");

AILog.Info(" - AISubsidy::GetSource returns STATION_INVALID for awarded subsidies.");

AISign.GetMaxSignID <- function()

{

	local list = AISignList();

	local max_id = 0;

	foreach (id, d in list) {

		if (id > max_id) max_id = id;

	}

	return max_id;

}

AITile.GetHeight <- function(tile)

{

	if (!AIMap.IsValidTile(tile)) return -1;

	return AITile.GetCornerHeight(tile, AITile.CORNER_N);

}

AIOrder.ChangeOrder <- function(vehicle_id, order_position, order_flags)

{

	return AIOrder.SetOrderFlags(vehicle_id, order_position, order_flags);

}

AIWaypoint.WAYPOINT_INVALID <- 0xFFFF;

AISubsidy.SourceIsTown <- function(subsidy_id)

{

	if (!AISubsidy.IsValidSubsidy(subsidy_id) || AISubsidy.IsAwarded(subsidy_id)) return false;

	return AISubsidy.GetSourceType(subsidy_id) == AISubsidy.SPT_TOWN;

}

AISubsidy.GetSource <- function(subsidy_id)

{

	if (!AISubsidy.IsValidSubsidy(subsidy_id)) return AIBaseStation.STATION_INVALID;

	if (AISubsidy.IsAwarded(subsidy_id)) {

		return AIBaseStation.STATION_INVALID;

	}

	return AISubsidy.GetSourceIndex(subsidy_id);

}

AISubsidy.DestinationIsTown <- function(subsidy_id)

{

	if (!AISubsidy.IsValidSubsidy(subsidy_id) || AISubsidy.IsAwarded(subsidy_id)) return false;

	return AISubsidy.GetDestinationType(subsidy_id) == AISubsidy.SPT_TOWN;

}

AISubsidy.GetDestination <- function(subsidy_id)

{

	if (!AISubsidy.IsValidSubsidy(subsidy_id)) return AIBaseStation.STATION_INVALID;

	if (AISubsidy.IsAwarded(subsidy_id)) {

		return AIBaseStation.STATION_INVALID;

	}

	return AISubsidy.GetDestinationIndex(subsidy_id);

}

AITown.GetMaxProduction <- function(town_id, cargo_id)

{

	return AITown.GetLastMonthProduction(town_id, cargo_id);

}

AIRail.RemoveRailWaypoint <- function(tile)

{

	return AIRail.RemoveRailWaypointTileRect(tile, tile, true);

}

AIRail.RemoveRailStationTileRect <- function(tile, tile2)

{

	return AIRail.RemoveRailStationTileRectangle(tile, tile2, false);

}

AIVehicle.SkipToVehicleOrder <- function(vehicle_id, order_position)

{

	return AIOrder.SkipToOrder(vehicle_id, order_position);

}

AIEngine.IsValidEngine <- function(engine_id)

{

	return AIEngine.IsBuildable(engine_id);

}

AIEngine._GetName <- AIEngine.GetName;

AIEngine.GetName <- function(engine_id)

{

	if (!AIEngine.IsBuildable(engine_id)) return null;

	return AIEngine._GetName(engine_id);

}

AIEngine._GetCargoType <- AIEngine.GetCargoType;

AIEngine.GetCargoType <- function(engine_id)

{

	if (!AIEngine.IsBuildable(engine_id)) return 255;

	return AIEngine._GetCargoType(engine_id);

}

AIEngine._CanRefitCargo <- AIEngine.CanRefitCargo;

AIEngine.CanRefitCargo <- function(engine_id, cargo_id)

{

	if (!AIEngine.IsBuildable(engine_id)) return false;

	return AIEngine._CanRefitCargo(engine_id, cargo_id);

}

AIEngine._CanPullCargo <- AIEngine.CanPullCargo;

AIEngine.CanPullCargo <- function(engine_id, cargo_id)

{

	if (!AIEngine.IsBuildable(engine_id)) return false;

	return AIEngine._CanPullCargo(engine_id, cargo_id);

}

AIEngine._GetCapacity <- AIEngine.GetCapacity;

AIEngine.GetCapacity <- function(engine_id)

{

	if (!AIEngine.IsBuildable(engine_id)) return -1;

	return AIEngine._GetCapacity(engine_id);

}

AIEngine._GetReliability <- AIEngine.GetReliability;

AIEngine.GetReliability <- function(engine_id)

{

	if (!AIEngine.IsBuildable(engine_id)) return -1;

	return AIEngine._GetReliability(engine_id);

}

AIEngine._GetMaxSpeed <- AIEngine.GetMaxSpeed;

AIEngine.GetMaxSpeed <- function(engine_id)

{

	if (!AIEngine.IsBuildable(engine_id)) return -1;

	return AIEngine._GetMaxSpeed(engine_id);

}

AIEngine._GetPrice <- AIEngine.GetPrice;

AIEngine.GetPrice <- function(engine_id)

{

	if (!AIEngine.IsBuildable(engine_id)) return -1;

	return AIEngine._GetPrice(engine_id);

}

AIEngine._GetMaxAge <- AIEngine.GetMaxAge;

AIEngine.GetMaxAge <- function(engine_id)

{

	if (!AIEngine.IsBuildable(engine_id)) return -1;

	return AIEngine._GetMaxAge(engine_id);

}

AIEngine._GetRunningCost <- AIEngine.GetRunningCost;

AIEngine.GetRunningCost <- function(engine_id)

{

	if (!AIEngine.IsBuildable(engine_id)) return -1;

	return AIEngine._GetRunningCost(engine_id);

}

AIEngine._GetPower <- AIEngine.GetPower;

AIEngine.GetPower <- function(engine_id)

{

	if (!AIEngine.IsBuildable(engine_id)) return -1;

	return AIEngine._GetPower(engine_id);

}

AIEngine._GetWeight <- AIEngine.GetWeight;

AIEngine.GetWeight <- function(engine_id)

{

	if (!AIEngine.IsBuildable(engine_id)) return -1;

	return AIEngine._GetWeight(engine_id);

}

AIEngine._GetMaxTractiveEffort <- AIEngine.GetMaxTractiveEffort;

AIEngine.GetMaxTractiveEffort <- function(engine_id)

{

	if (!AIEngine.IsBuildable(engine_id)) return -1;

	return AIEngine._GetMaxTractiveEffort(engine_id);

}

AIEngine._GetDesignDate <- AIEngine.GetDesignDate;

AIEngine.GetDesignDate <- function(engine_id)

{

	if (!AIEngine.IsBuildable(engine_id)) return -1;

	return AIEngine._GetDesignDate(engine_id);

}

AIEngine._GetVehicleType <- AIEngine.GetVehicleType;

AIEngine.GetVehicleType <- function(engine_id)

{

	if (!AIEngine.IsBuildable(engine_id)) return AIVehicle.VT_INVALID;

	return AIEngine._GetVehicleType(engine_id);

}

AIEngine._IsWagon <- AIEngine.IsWagon;

AIEngine.IsWagon <- function(engine_id)

{

	if (!AIEngine.IsBuildable(engine_id)) return false;

	return AIEngine._IsWagon(engine_id);

}

AIEngine._CanRunOnRail <- AIEngine.CanRunOnRail;

AIEngine.CanRunOnRail <- function(engine_id, track_rail_type)

{

	if (!AIEngine.IsBuildable(engine_id)) return false;

	return AIEngine._CanRunOnRail(engine_id, track_rail_type);

}

AIEngine._HasPowerOnRail <- AIEngine.HasPowerOnRail;

AIEngine.HasPowerOnRail <- function(engine_id, track_rail_type)

{

	if (!AIEngine.IsBuildable(engine_id)) return false;

	return AIEngine._HasPowerOnRail(engine_id, track_rail_type);

}

AIEngine._GetRoadType <- AIEngine.GetRoadType;

AIEngine.GetRoadType <- function(engine_id)

{

	if (!AIEngine.IsBuildable(engine_id)) return AIRoad.ROADTYPE_INVALID;

	return AIEngine._GetRoadType(engine_id);

}

AIEngine._GetRailType <- AIEngine.GetRailType;

AIEngine.GetRailType <- function(engine_id)