FAQ

Content:

Technical Stuff

What Software do I need to run MegaMek?
How do I install and run MegaMek?
Stable, Dev, Exp... Which Megamek release should I use?
I am on a Mac and I can’t find my data and log directories. How am I supposed to add my own custom designs, maps, etc.?
Mac fanboy here again, How do I open up multiple instances of MegaMek?
Why can’t I host a game?
How do I use more, or less, memory?
How do I start a dedicated server?

Unit Quesions

When I turn on the “Canon Units Only” option, I lose a bunch of units that I know should be canon.
Why can't I find unit XXX?
Why is unit XXX marked as illegal, it fits the official Record Sheet?

Misc

Why is the bot so stupid?
Are the dice conspiring against me?

Development

How do I submit a bug or learn about the known bugs?
How do I submit my suggestion or idea for a new feature?
When will rule/feature X be supported?
Can I join the MegaMek developers?
I am not a developer. Is there any other way I can help?

Technical stuff

What software do I need to run MegaMek?
MegaMek will run on any operating system that can run a Java Virtual Machine, including Windows, Mac OS X, and Linux. Your computer might already have Java installed, but it is probably a good idea to get an up-to-date version, even if it is installed. The primary reason that MegaMek will not run on some computers is that Java is either not installed or not up-to-date.

How do I install and run MegaMek?
MegaMek comes in a zip file. You will need to unzip it using an appropriate unzipping utility. For example, you could use 7-Zip or WinZip on windows. Simply unzip MegaMek into the directory of your choice. We recommend that you do not unzip a new release into the same directory as an older release, as this can often cause problems if files have changed. As of version 0.35.13, We are now packaging MegaMek in operating system-specific platforms. To run MegaMek on Windows and Mac OS X, simply double-click on the MegaMek icon. In a unix environment, you can run the startup shell script or run the program from the command line:

java -jar MegaMek.jar &

On older versions, Mac OSX users will need to double-click the MegaMek.jar file.

Stable, Dev, Exp... Which Megamek release should I use?
The Megamek project uses several different types of official releases.

Stable releases are, as the name suggest, the most stable. These are released less frequently and have undergone the most testing.

Between stable releases the project has two more frequently released versions. The first of which is the dev snapshot releases. These are released periodically during the development process and will contain new features that are being worked that aren't yet in the stable release. Since these releases are currently in development there is a much higher likelihood of encountering bugs.

The final release type is experimental. These releases come from the experimental branch and generally contain changes that may not make it into development or are longer term projects. These releases may or may not happen depending on whether there are experimental changes currently in development.

In addition to the official releases, Ralgith makes unofficial custom releases. The difference between these releases and the official releases is that the custom releases contain more data (units, maps, images) that is not in the official release.

When making bug reports or asking questions about functionality, it is important to specify what release you are using.

I am on a Mac and I can’t find my data and log directories. How am I supposed to add my own custom designs, maps, etc.?
If you are using a version between 0.35.13 and 0.35.21, you will need to right-click (or control + click) on the Megamek icon and choose “Show Package Contents.” Then navigate to Contents > Resources and you will see both your data and log directories. As of version 0.35.21, the data, log, and configuration directories should all appear in the main folder.

Mac fanboy here again, How do I open up multiple instances of MegaMek?
By default, OSX applications will only open a single instance. To open up a second instance of MegaMek, you will have to use the Terminal application (in Application/Utilities). Navigate to your MegaMek directory and type:

open -n MegaMek.app &

The “-n” argument tells OSX to open up a new instance of the application.

Why can’t I host a game?
If you are hosting a game over the internet, and other people cannot connect to your address, then you probably have port forwarding disabled in your router. You will need to allow port forwarding from the router to your computer on the port that MegaMek is using (2346, by default). How to do this will vary depending upon what type of set up you have for connecting with the internet. Check the instructions for your router. You can also try portforward.com, which has instructions on how to forward ports for many routers.

How do I use more, or less, memory?
By default, MegaMek uses up to 1024 megabytes (1 gigabyte) of memory. This amount of memory is sufficient for most games, but when playing large games against the bot, higher amounts of memory can boost performance. How you change the maximum memory allowed varies by operating system. On windows, open up the MegaMek.l4j.ini file and change the line that says “-Xmx1024m” to the amount of memory you want. For example, if you want 512 megabytes of memory, you would change this line to “-Xmx512m”. On Mac OSX, you want to right-click on the MegaMek icon and choose “Show Package Contents.” Then open up Contents/Info.plist. Look for the line that says “-Xmx1024m” and edit this as above. On a UNIX system you will need to edit the startup.sh file's last line, or just add the memory argument directly to your java command if launching manually. For example:

java -Xmx512m -jar MegaMek.jar &

How do I start a dedicated server?
It depends what operating system you are on, but in every case you will need to do it from the command line (DOS on Windows, Terminal/Xterm on Mac OSX and unix). Navigate to your MegaMek directory and type:

Windows:

MegaMek -dedicated -port XXXX

Mac OSX:

open MegaMek.app –args -dedicated -port XXXX &

Unix:

java -jar MegaMek.jar -dedicated -port XXXX &

Where you replace XXXX with the port you would like to use. On a Unix/OSX system, we also recommend you preface your command with a nohup command to avoid interruption.You can test your dedicated server now by opening a new MegaMek window and connecting to localhost on the given port number. On Mac OSX, note that you will need to use the “-n” argument to open up a new instance of MegaMek, once your dedicated server is running.

Unit Quesions

When I turn on the “Canon Units Only” option, I lose a bunch of units that I know should be canon.
We are currently in the process of recoding the canon status of all units as part of the Master Unit List project. Please be patient.

Why can't I find unit XXX?
There are three possibilities:
1st, did you check the different rules levels? Perhaps the unit you are looking for is Advanced or Experimental
2nd, we forgot to add it, then please report it either to the bug tracker or the forums
3rd, the unit has not yet passed the two months moratorium period since its official Record Sheet got released. You will have to wait that that happens.

Why is unit XXX marked as illegal, it fits the official Record Sheet?
Most of the times that means that the unit is using ferro-fibrous armor and is using the old armor rules, superceded by TechManual. Armor is now always rounded down, making some units overweight until a new Record Sheet is released.

Misc

Why is the bot so stupid?
The bot has not been overhauled for a long time and is completely unaware of many of the new optional rules available in MegaMek, so it will do stupid things like jump off of cliffs if you let it. For the best bot experience, play with a minimum of extra options enabled. We plan on making the bot better at some point, but right now our priority is on other issues.

Are the dice conspiring against me?
Short answer: No. Long answer: The dice use the standard Java random number generation routines. You can find them described in the Sun documentation. The same routine is used for every dice roll in the game. These routines have been tested, and they behave as closely as possible to real dice as is possible on a computer. To put it another way, every time the virtual die is rolled, it stands a one-in-six chance of generating each number, one through six.

Development

How do I submit a bug or learn about the known bugs?
Bugs are listed in the bug tracker on the project page. For your bug to be at its most useful, you should be able to describe it accurately, and preferably, you should be able to describe how to reproduce the bug. Please include the megameklog.txt file from your game when submitting bugs.

How do I submit my suggestion or idea for a new feature?
Similar to the bug tracker, there’s a feature requests tracker, also on the project page.

When will rule/feature X be supported?
The developers work on MegaMek as a hobby. This is nice for us, since we enjoy it, and nice for you since we’re able to give you this program for free. However, it means the only honest answer to this question is that we’ll work on rule/feature X when it interests us. If this isn’t fast enough..

Can I join the MegaMek developers?
Certainly! MegaMek is open source and anybody is welcome to contribute. A great way to get involved is to fix a bug or implement a new feature, and submit your patch to the patches section on the project page. Organization is fairly informal at present. If you want to make sure you’re not duplicating someone else’s work, you might post a message in the forums to announce your interest, but otherwise, go wild.

I am not a developer. Is there any other way I can help?
How would you like to help? Are you good with Art? Writing documentation? If you like playing best, submitting accurate and complete bug reports is always a big help.