July 12, 2006

Tremulous: The best free software game ever?

Author: Joe Barr

Linux and open source software lag behind the proprietary market in the number and quality of available video games, especially in the realm of first-person shooters (FPS), a genre dominated by the likes of Doom, Quake, Unreal, Half-Life, and Halo. Here, Linux is an afterthought, if not ignored completely. Tremulous, a mixture of FPS and RTS (real-time strategy) written by Tim Angus, is an exception to that rule.

Tremulous uses the free software version of the Quake 3 engine, which was released under the GPL by id Software last year. I downloaded the Linux version of Tremulous 1.1.0 -- it also runs on Windows -- from the files page on tremulous.net and installed it on an IBM ThinkPad T40 laptop, a desktop box, and a workstation. In each case, all it took was entering the following command as root and then following the prompts:

sh tremulous-1.1.0-installer.x86.run

Tremulous is based on a client-server architecture, but you have a choice as to how to run the server. You can run it as a completely stand-alone, dedicated process using the included tremded program, or you can run a server and client on one machine simultaneously. There isn't a lot of documentation available on tremded, but it comes with a sample configuration file in the install subdirectory, and there is another version of server.cfg on tremulous.info, an independent Tremulous site.

Which to use? If you are setting up a dedicated machine for Tremulous game play on the Internet, choose tremded, for continuity if for no other reason. For a quick pick-up game on the LAN, all you need do is choose the Create Server option from the client.

I wanted to be able to test Tremulous locally, so I started the Tremulous client on an otherwise idle workstation, clicked Create Server, selected a map, and changed the name to Wart's Lair. Then it was back to my everyday desktop machine to try it out. I started the game, selected Local, and then Refresh List. There it was: Wart's Lair appeared as my only choice for a server. I double-clicked on it and was connected.

Click to enlarge

The game

Tremulous is basically a struggle between two teams: the humans, a species I will assume you are familiar with, and the aliens, which look like bugs and sometimes crawl along walls and ceilings. During the game, each side progresses through three stages, with advanced abilities and equipment coming in during the second and third stages. There is one major difference between the species, beyond being on different teams. Humans can upgrade their equipment. Aliens can upgrade themselves. Both species have structures peculiar to themselves.


In the beginning, there are only two alien classes: Grangers and Dretches. Grangers are builders -- they build structures to support alien activities. Dretches are soldiers, used for attacking humans and human structures. There are basic and advanced versions of both classes, as there are of all classes, including Basilisks, Marauders, Dragoons, and Tyrants, which arrive on the scene later.

Various types of alien structures can be built during the game, but the Overmind -- the collective consciousness with control over all other alien structures -- has to be the first structure built. If it is destroyed during the game, all other existing structures except for Eggs cease to function, and the aliens themselves lose the ability to change to a more advanced class until a new Overmind is created.

Eggs are structures that spawn additional aliens. Other structures include Acid Tubes, Barricades, Trappers, Boosters, a Hovel, and Hives. Each has a purpose in the war against humans.

Q&A with Timbo

NewsForge: Is it correct that you are the lead developer of the game? I see in the credits that a number of people are listed. Did they volunteer their efforts, or are they

Tim Angus: I'm the only programmer and the director/leader of the project. The
other developers are all artists. Tremulous was completely non-commercially

NF: The notion of mixing a team-based FPS with RTS is interesting. Is
this something unique to Tremulous?

TA: The concept isn't hugely new. The inspiration for Tremulous came from a
Quake 2 modification named Gloom, but there are also parallels with "Natural Selection" for Half Life and the commercial game "Savage." Tremulous is the first completely free implementation of the concept, and also one of the more successful games to have spawned from id software's policy of GPL source release.

NF: Is there, or will there be, a commercial side to Tremulous?

TA: Unlikely. We may put a PayPal donation button (or similar) on the Web site, but I don't really see opportunity to commercially exploit it otherwise. This is partly because I believe the success of Tremulous is largely a function of its freedom. If people actually had to pay money to play it, I think it's highly unlikely that it would be popular.


Humans are spawned with either a Rifle or Construction Kit. A human with a Construction Kit serves the same function as an alien Granger; they are both builders. One with a Rifle is the equivalent of an alien Dretch -- a foot soldier whose job is to attack the enemy. Other weapons humans can acquire during game play are the Blaster, Pain Saw, Shotgun, Las Gun, Chainsaw, Mass Gun, Pulse Rifle, Grenade, Flamethrower, and Lucifer Cannon.

Humans can also upgrade their equipment, in addition to their weapons, buying such things as Light Armor, Helmets, Medkits, Battery Packs, Jet Packs, and Battlesuits.

Human structures begin with the Reactor, and just as with the alien Overmind, it must be the first structure created. If it is destroyed, all other structures except for Telenodes cease to function. Telenodes are to humans as Eggs are to aliens; it is from these structures that humans are spawned. Other structures include Machine Gun Turrets, Tesla Generators, Armories, Defense Computers, Medistations, and Repeaters.

A tip in the dark

If the game screen is too dark for you to clearly see all the screen areas, there are two quick ways to fix that. As noted in the FAQ, you don't need a flashlight. The quickest fix is to pop open the command console with the ~ key, enter /r_gamma 2, and then close the console.

If the thought of entering a command instead of clicking a rodent fills you with dread, you can also adjust the Brightness level by pressing the Esc key, then clicking on Options -> System -> GFX Software and using the slider to set the brightness to your liking.

One more tip -- don't play Tremulous in windowed mode and have Gaim running at the same time. If you do, an incoming message might get you some place that you can't escape from. At least I couldn't.


Tremulous is the best free software FPS game I've had the pleasure of playing, and I'm not alone in this opinion. It also has a community growing up around it, which should aid not only in growing its popularity but also in continuing improvements.

Good for id Software for freeing the engine, and good for Darklegion Development for what its developers have done with it. Give it a try. You'll like it.


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