What's the best open source game to learn from?

Question

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For me to read code and learn, not to play...

...of course ;-)

Michał Piaskowski · Answer 1 · 2010-07-02T06:00:39.593

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Quake (1,2 and 3) and DukeNukem 3D source code is available under the GPL.

edited Jul 02 '10 at 06:00

answered Oct 22 '08 at 18:27

Michał Piaskowski

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Although originally commercial, the fact that these games are now released under the GPL make them the best open source games. Ever. You can't compete with Quake. You can't compete with what it means. – Vicent Marti Oct 22 '08 at 20:00
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Just a quick "legalese" comment: the source code of the "game engines" for these games is open source now. The graphics, maps, characters, story, etc. are still proprietary copyrighted items. If you want to play them, you have to either use the files provided with the shareware version or buy it :( – Joe Pineda Oct 22 '08 at 21:21
Agreed, but for learning games programming, these sources are invaluable! – Gary Willoughby Oct 23 '08 at 17:25
Another thing you can learn from these is historic, how they managed to get it to work on the hardware of the day. – Brad Gilbert Oct 24 '08 at 16:30
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Although being good games this doesn't mean the code is readable and good to play with. It's also heavily optimized, that will bring you some headaches in understanding the real inner workings. Anyway, if you like the procedural approach in games you'll be pretty much satisfied with it. – Manuel Jan 02 '09 at 17:28
Agreed, can't beat quake. Try OpenArena for a fully free package, and ioquake3 for a somewhat modernized version – Jan 06 '09 at 07:15

score 67 · Answer 2 · edited Nov 14 '08 at 10:21

67

If part of the reason for open-source code is for code to be reused and recycled as it evolves, then I think influence and legacy would be two large factors in this decision. On this basis, I would probably vote Rogue / Hack / Nethack. It was one of the seminal influences behind the hack-and-slash dungeon-crawling genre, living on today in thriving communities that still play these old ASCII games, as well as having a significant influence on some of the most popular graphical games of all time, such as Diablo and Diablo 2.

edited Nov 14 '08 at 10:21

Epaga

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answered Oct 22 '08 at 18:29

HanClinto

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Don't forget the Moria/Angband development tree. – David Thornley Nov 14 '08 at 21:41
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And Nethack has a a lot of technology in the code. UI abstraction layer, serialzation, domain specific data description language with a compiler, etc. – Darron Jan 06 '09 at 18:26
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And remember the reason it's called NetHack is because it was one of the first programs written collaboratively over the net. It was so new that deserved a special distinction in the name! – ilya n. Jun 21 '09 at 08:57
I think you can put MUDs in that tree as well: multiplayer realtime Internet text adventure game. CircleMUD has very good documentation and I started with that a few years ago: http://www.circlemud.org/ – karlphillip Oct 18 '11 at 16:47

Vinko Vrsalovic · Answer 3 · 2008-10-22T18:29:21.873

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Battle for Wesnoth

That said, you can devote some time reading http://en.wikipedia.org/wiki/List_of_open_source_games

It also depends what exactly do you want to learn... For instance there is an annual competition for games written in Pygame

edited Oct 22 '08 at 18:29

answered Oct 22 '08 at 18:23

Vinko Vrsalovic

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score 37 · Answer 4 · answered Nov 14 '08 at 10:23

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What about OpenTransportTycoon? :) Come one people - that's got to be the best!

http://www.openttd.org FTW! ;)

answered Nov 14 '08 at 10:23

Israr Khan

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the best ever, now only if they could create good API for programming your own bots. – lubos hasko Nov 14 '08 at 10:47
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..They've come close with NoAI now. oTTD is an interesting read, I've been able to learn a fair bit just by reading the oTTD source code. – Sukasa Mar 03 '09 at 19:39

score 31 · Answer 5 · answered Oct 22 '08 at 18:25

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How about FreeCiv?

answered Oct 22 '08 at 18:25

Thomas Owens

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One problem I have with FreeCiv is it doesn't run smoothly on older hardware. Otherwise I love it. – Brad Gilbert Oct 24 '08 at 16:31
I've got a really really old original Pentium running BSD that I run Freeciv on, it runs fine, except for the graphics in the client, the window is too large to fit on my older resolution monitor. So, i can't see the tabs on the bottom. – stephenbayer Nov 14 '08 at 21:26
Try the trident tileset for older computers. Should work fine. – u0b34a0f6ae Mar 10 '10 at 21:28

Corbin March · Answer 6 · 2008-10-22T21:40:49.227

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Check out Kenta Cho's games: http://www.asahi-net.or.jp/~cs8k-cyu/index_e.html. Most of them are written in D and use Simple DirectMedia Layer.

They're a lot of fun and the source is extremely readable - a great showcase for the D language.

Torus Trooper screenshot:

alt text http://images.macworld.com/images/legacy/images/content/torus.jpg

edited Oct 22 '08 at 21:40

answered Oct 22 '08 at 21:23

Corbin March

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Whoa, +1 for neat games written in D! – Matthew Olenik Apr 15 '09 at 10:56
Kenta Cho's games are awesome - the best probably being Gunroar or rRootage. – Steve Claridge Mar 06 '10 at 14:21

score 25 · Answer 7 · answered Oct 22 '08 at 21:44

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There is a very good text based role playing game called 'make', you are on a quest to find hidden dependancies guarded by bearded sages and wrestle patches from them.

answered Oct 22 '08 at 21:44

Martin Beckett

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score 20 · Answer 8 · answered Oct 22 '08 at 18:24

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Robocode is pretty awesome. See also its entry at Wikipedia.

answered Oct 22 '08 at 18:24

Martijn

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score 16 · Answer 9 · answered Oct 22 '08 at 21:46

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This one... the original Star Trek. PDP11 rulez! :)

answered Oct 22 '08 at 21:46

Kevin Little

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I remember playing this at school on a dot-matrix console... right up there with a civil war program and some wierd mafioso program (that the name escapes me atm) – Christopher Klein Oct 23 '08 at 17:27
You can download a PDP-11 version of Empire, too! http://www.classicempire.com – Walter Bright Nov 10 '08 at 05:42
@Christopher Klein: probably Syndicate – Adriano Varoli Piazza Jan 06 '09 at 18:48

score 16 · Answer 10 · answered Mar 03 '09 at 19:11

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alt text http://sc2.sourceforge.net/screenshots/melee2.png

Ur Quan Masters - Star Control 2 update.

answered Mar 03 '09 at 19:11

jle

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Just wanted to say this is *excellent*. The feel of the space combat is spot on. – Alex Sep 05 '09 at 14:10
Excellent game. This screenshot perhaps doesn't do it justice; Star Control II is often rated one of the best games ever (http://en.wikipedia.org/wiki/Star_Control_II#Accolades). – Josh Kelley Jan 25 '10 at 01:57

score 12 · Answer 11 · answered Oct 22 '08 at 19:42

I'd have to go with GNU Chess.

If you're really interested in looking at the code. From the wiki: "Version 5 was essentially a complete rewrite from scratch of GNU Chess to eliminate spaghetti code and replace antiquated data structures with more advanced computer chess implementation techniques."

Michael Burr · Answer 12 · 2008-10-22T18:54:54.740

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I can't believe Hunt the Wumpus hasn't been mentioned.

Or Star Trek?

edited Oct 22 '08 at 18:54

answered Oct 22 '08 at 18:46

Michael Burr

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My favorite implementation is "Be the Wumpus", which features audio ONLY. – mdm Oct 30 '09 at 18:53

score 10 · Answer 13 · answered Nov 14 '08 at 20:44

10

two words: Frozen Bubble.

answered Nov 14 '08 at 20:44

Chad

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Mnementh · Answer 14 · 2009-04-15T10:46:56.570

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My personal favorite is UFO Alien Invasion. I loved the original UFO and this is a really good clone.

edited Apr 15 '09 at 10:46

answered Nov 14 '08 at 20:52

Mnementh

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score 8 · Answer 15 · answered Oct 22 '08 at 18:47

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What? No one here likes Tux Racer?

I just LOVE that game!!! It's fast paced and can run on almost any decent modern computer (no need for expensive video cards). And it runs on Windows, too!! Furthermore, it demonstrates that "penguins can fly" (and even surpass speed of sound :P)

answered Oct 22 '08 at 18:47

Joe Pineda

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It's been my favorite one for a while too! – Pascal Paradis Oct 22 '08 at 18:51
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I won't vote you down, but I have never been impressed with TuxRacer. – Knobloch Oct 22 '08 at 19:00
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Tux Racer was neat back when I first got MesaGL working, but I can't help seeing it as a perfect example of how linux is a second-class citizen in the gaming world. – Adam Lassek Nov 14 '08 at 20:49

score 8 · Answer 16 · answered Oct 22 '08 at 19:20

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No question in my mind, GL Tron. How can you not love it?

http://en.wikipedia.org/wiki/GLtron

answered Oct 22 '08 at 19:20

jeph perro

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Because it's kind of boring. It's like Minesweeper for Tron fans. Never the less, I will not vote it down. – Cristian Ciupitu Oct 24 '08 at 18:13
Against the computer it's boring indeed. But it's a lot of fun against real people. – Ryan Lundy Jun 08 '10 at 04:02

Esko Luontola · Answer 17 · 2011-08-23T23:05:46.537

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Jagged Alliance 2

Its source code was released in 2004 (I think) and since then it has been improved very much by the mod community. The mod goes under the name JA2 v1.13 and the community resides at Bear's Pit.

P.S. For reading and learning from the code, this might not be the best project. It's old C code with many functions spanning hundreds of lines. Unless you want to learn how to work with legacy code, playing it is more fun. ;)

edited Aug 23 '11 at 23:05

answered Mar 03 '09 at 19:32

Esko Luontola

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Jagged Alliance 2 would be a good start if you want to practice your review skills. – mbx Aug 23 '11 at 19:01

score 5 · Answer 18 · answered Oct 22 '08 at 18:28

well....

If you'r into Flight simulators the definitively check out Free Space just can

http://scp.indiegames.us/

There are also tons of mods... a very nice one is on the battlestar gallactica universe where you actually fly the viper mark VII

http://www.game-warden.com/bsg/

have fun... errr, of course, where's my head...

happy code reading ;-)

Chris Porter · Answer 19 · 2008-10-22T18:42:07.010

If your intent is to see how a game works and are willing to spend a small amount of money to see it, I highly recommend the Torque Gaming Engine from GarageGames. For $150 you get the entire engine source code of a AAA game title (Tribes 2). The content was ripped so you aren't buying Tribes 2, but content is easy to replace. Compared to the cost of other comparable engines, Torque is an amazing bargain. And if you ever decide to produce a game, you can do so without overbearing licensing restrictions.

EDIT: I know its not Open Source, but for your purpose of learning code it should qualify. The engine is coded in C++ and there is a script layer that is similar in syntax to C#/Java.

Walter Bright · Answer 20 · 2008-12-05T02:58:43.810

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alt text http://www.classicempire.com/emlogo.jpg

Empire, the Wargame of the Century, naturally. You can download it from classicempire.com. Empire has been flunking out students and wrecking marriages since the 1970's.

edited Dec 05 '08 at 02:58

answered Nov 10 '08 at 05:33

Walter Bright

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anything that can get this has got to be good: http://www.classicempire.com/epyx.html – BCS Dec 03 '08 at 17:39

score 5 · Answer 21 · answered Nov 14 '08 at 10:19

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Sauerbraten Very nice FPS

answered Nov 14 '08 at 10:19

GvS

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also the code is extremely elegant and clean, a master piece of software development. – levhita Nov 14 '08 at 20:43
The code follows a certain philosophy and really does well in being minimalistic. It's actually a great piece of code if you wish to see how clean and elegantly optimizations can be done. – Hakkar Feb 24 '10 at 03:01

score 4 · Answer 22 · answered Oct 22 '08 at 20:01

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Wormux really has a fantastic architechture. i'm a professional game developer and i think that these guys really might be too. the quality of the work smells of years of game dev experience.

answered Oct 22 '08 at 20:01

DavidG

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score 4 · Answer 23 · edited Mar 18 '11 at 18:17

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It's got to be either Rogue

Rogue Screenshot http://upload.wikimedia.org/wikipedia/en/a/af/Rogue_Unix_Screenshot_CAR.PNG

or Empire I've invested (lost) so much time in both of those.

edited Mar 18 '11 at 18:17

John Gietzen

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answered Nov 14 '08 at 10:44

Denis Hennessy

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score 4 · Answer 24 · answered Nov 14 '08 at 20:27

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I've spent many hours playing FreeCol (a clone of Sid Meier's Colonization).

I mean "studying the source code of FreeCol".

answered Nov 14 '08 at 20:27

JPLemme

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score 4 · Answer 25 · answered Jun 01 '10 at 02:38

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Quite recently a few of the games from the Humble Indie Bundle went open source and are probably pretty interesting for people to look into. Gish, Lugaru, and Penumbra were all opened.

http://www.wolfire.com/humble

answered Jun 01 '10 at 02:38

Tyler

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score 3 · Answer 26 · edited Oct 22 '08 at 21:43

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Dopewars is fun to play on the internet or on a LAN with friends. And it runs on Windows, OSX, Linux, iPhone and there is an adaptation on Facebook.

edited Oct 22 '08 at 21:43

Adam Bellaire

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answered Oct 22 '08 at 18:54

Pascal Paradis

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score 3 · Answer 27 · answered Oct 24 '08 at 17:44

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Depending on what platform you're going for, the XNA guys have a few "starter kits" of ready to build projects, the code is available, but it's not explicitly open source:

http://creators.xna.com/education/starterkits/

answered Oct 24 '08 at 17:44

user17956

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score 3 · Answer 28 · answered Jan 06 '09 at 18:31

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So many games, so little time.

answered Jan 06 '09 at 18:31

pmg

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score 2 · Answer 29 · edited Feb 08 '17 at 14:20

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Hedgewars it's fun, runs smoothly, has nice graphics and everyone who liked Worms World Party will enjoy it.

  To compile and install you need:

  Qt >= 4.4
  FreePascal >= 2.2.0
  SDL >= 1.2.5
  SDL_net >= 1.2.5
  SDL_mixer >= 1.2
  SDL_image >= 1.2
  SDL_ttf >= 2.0
  CMake >= 2.6.0

alt text

edited Feb 08 '17 at 14:20

Community

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answered Jan 25 '10 at 01:12

xadoc

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Clearly has nothing to do with Worms. – L̲̳o̲̳̳n̲̳̳g̲̳̳p̲̳o̲̳̳k̲̳̳e̲̳̳ May 09 '10 at 03:27

score 2 · Answer 30 · answered Oct 22 '08 at 19:28

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Warsow, obviously.

It's a FPS, technically advanced as Quake 3, open source, with nicely documented code and a great community.

answered Oct 22 '08 at 19:28

friol

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That's because it uses Quake 3 code base. – Eugene Bujak Jul 04 '09 at 14:20

score 2 · Answer 31 · answered Oct 22 '08 at 19:58

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I can't believe, nobody mentioned Armagetron Advanced yet!

For fans of the movie Tron, this is a nice way to waste some time online with other players worldwide.

answered Oct 22 '08 at 19:58

HS.

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wusher · Answer 32 · 2008-10-22T20:06:56.717

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Duke3D released their source code. That's the best game ever. Source code is number 15 under duke3d

edited Oct 22 '08 at 20:06

answered Oct 22 '08 at 20:00

wusher

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score 2 · Answer 33 · answered Oct 24 '08 at 17:58

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A classic: Crowther/Woods Adventure ;-)

answered Oct 24 '08 at 17:58

Andreas Scherer

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score 2 · Answer 34 · answered Nov 14 '08 at 20:32

No shout outs to Angband yet? It went under new "ownership" in March of this year and is still the most addictive fantasty/dungeon style game I've seen. Source is readily available and it is pretty slick to see how a program can still be heavily active after its initial release back in 1993, or even later, if memory serves on its lifetime.

score 2 · Answer 35 · answered Nov 14 '08 at 20:50

2

No one mentioned freedroidrpg yet.

answered Nov 14 '08 at 20:50

Mnementh

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score 2 · Answer 36 · answered Mar 03 '09 at 18:50

Freespace 2 source code. It is based off of the original Volition Freespace 2 (released as open source). This is production (and thus "battle tested") code and will give you a good look at how shipping titles look (with all of the warts).

You can gain access to the FS2_open source through SVN here:

http://scp.indiegames.us/links.php

score 2 · Answer 37 · answered Mar 03 '09 at 18:54

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I've spent more time with Glubulation 2 Than any other open source game. Its an innovative and fresh variation on the RTS genre.

answered Mar 03 '09 at 18:54

SingleNegationElimination

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score 2 · Answer 38 · answered Apr 15 '09 at 10:48

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Tremulous is a good multiplayer-game.

answered Apr 15 '09 at 10:48

Mnementh

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score 1 · Answer 39 · answered Jan 25 '10 at 01:22

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Completely surprised that FreeCiv didn't get a mention yet. It is truly the best online multiplayer game out there. And I have played it for hours.

As for compiling, you can pick between the SDL client and the GTK client.

answered Jan 25 '10 at 01:22

Nathan Osman

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FreeCiv is currently the 5th most popular answer. ;) – CoderDennis Jan 25 '10 at 01:45

score 1 · Answer 40 · answered Mar 04 '10 at 16:38

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Distributed by Microsoft MechCommander 2 (good mech game).

answered Mar 04 '10 at 16:38

gorsky

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score 1 · Answer 41 · edited Feb 08 '17 at 14:22

1

TeeWorlds alt text

edited Feb 08 '17 at 14:22

Community

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answered Mar 04 '10 at 16:46

Tim

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Mnementh · Answer 42 · 2009-06-21T10:39:43.490

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And I will add a console-game: Meteora Evolution. It is a homebrew-game for the Nintendo DS and Open-Source.

edited Jun 21 '09 at 10:39

answered Nov 14 '08 at 20:57

Mnementh

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score 1 · Answer 43 · answered Nov 14 '08 at 20:57

1

Gnu-Backgammon.

answered Nov 14 '08 at 20:57

alexmeia

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score 1 · Answer 44 · answered Nov 14 '08 at 21:05

1

Torcs, the Open Racing Simulator http://torcs.sourceforge.net/

answered Nov 14 '08 at 21:05

Darkwoof · Answer 45 · 2008-12-17T13:45:45.900

I don't think it counts as "open-source", but I loved QBasic Gorilla.Bas grin I used to edit it to make all buildings disappear when the banana hits the sun; then it's a Banana Free-For-All! xD

I also took the liberty to rename the game QBrian Gorilla to make fun of a friend of mine... Lame, I know, but hey, I was 14. Haha..

QBasic was the first programming language I got into, before later moving on to VB, and then ASP, PHP and VB.Net. Ah, nostalgia... =)

score 1 · Answer 46 · answered Mar 03 '09 at 19:03

1

Open Arena, the best of Quake 3 engine, entirely open-source.

answered Mar 03 '09 at 19:03

rogeriopvl

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score 0 · Answer 47 · answered Oct 22 '08 at 18:24

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Do unintentional source releases count? If so, Half-Life 2 and EVE (though it was only the client code)

answered Oct 22 '08 at 18:24

Chris Porter

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No, because they are not open-source – jjnguy Oct 22 '08 at 18:25
More precisely: they are illegal (to obtain and own). – steffenj Oct 22 '08 at 18:56

score 0 · Answer 48 · edited Jun 20 '20 at 09:12

The MMORPG Ryzom was open sourced a few days ago (blog post).

While I'm not that well versed in game programming, paroneayea's comment on reddit makes me think it's worth a look:

It's hard to understate how big of a release this is. The volume of assets here, the size of the codebase.. The fact that anyone can run their own MMORPG server, or contribute back useful assets to make it into the main server!

Honestly I don't think I've been this excited about the freeing of a project since Blender was released as free and open source software nearly a decade ago.

Source code - Media assets

score 0 · Answer 49 · answered Nov 14 '08 at 20:53

0

Global Thermonuclear War (http://en.wikipedia.org/wiki/WOPR) or, tic tac toe

answered Nov 14 '08 at 20:53

Tim

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Hey, it isn't open source, he had to hack into their servers to play it.. :P – Daniel Dimovski Mar 14 '10 at 23:11

score 0 · Answer 50 · answered Dec 17 '08 at 14:35

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If you're looking for a very quick C#.NET implementation of the classic Balderdash, check out the Digger source here:

http://www.lutzroeder.com/silverlight/

answered Dec 17 '08 at 14:35

Nick Gotch

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driAn · Answer 51 · 2009-01-06T18:20:25.913

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It's clearly AssaultCube ;) a fast and fun first-person-shooter that comes as a 40mb package.

alt text http://assault.cubers.net/pics/main_actioncube.jpg

Written in messy C++ using SDL, OpenGL and OpenAL :P

edited Jan 06 '09 at 18:20

answered Jan 06 '09 at 18:09

driAn

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score 0 · Answer 52 · answered Jan 13 '11 at 06:14

0

GNU Chess is the best. but game play wise people prefer Warsaw first person shooter game.

answered Jan 13 '11 at 06:14

KnightScott

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score 0 · Answer 53 · answered Mar 29 '11 at 19:49

0

Ubran terror is a great counter strike like game. http://www.urbanterror.info/news/home/

answered Mar 29 '11 at 19:49

mcginleyr1

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score 0 · Answer 54 · answered Mar 29 '11 at 19:54

0

Megaroids on the Atari ST. Was the demo application for the Megamax C compiler. Played it in Midres (640x200x4colors). Simple game that have this "one more" spirit.

answered Mar 29 '11 at 19:54

ThorN

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score 0 · Answer 55 · answered Mar 29 '11 at 20:48

0

I played a lot myself at Chromium. Back in 2005 it was ship with Mandrake distribution. All my no-I-will-never-use-Linux-but-only-consider-Windows friends where amazed by its quality, beauty and fast pace style.

Chromium screenshot. A must according to me.

answered Mar 29 '11 at 20:48

yves Baumes

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What's the best open source game to learn from?

55 Answers55