Friday, August 6, 2010

The Lost Battle - a ruby multiplayer game with Gosu and Chipmunk

This is a game I recently built to learn ruby in conjunction with the Gosu game engine and the Chipmunk physics engine.



The source of the game can be found at it's google code page here:

You can checkout using Mercurial with: hg clone the-lost-battle


For the game to run, it requires the following:

Running the game

To launch the game, fire up your terminal, navigate to the game's directory and run main.rb with the ruby interpreter: ruby main.rb
Or ruby1.9 main.rb if you have multiple versions of ruby installed.

After you click start game on the main screen, you will see the player selection, similar to the second screenshot above. If you do not have any joysticks connected, you will only be shown 1 player slot and the game will be unable to start since it requires 1 < players <= 4. Therefore, with a single joystick connected, you will be able to play a 2 player player with the keyboard+mouse and the other player with the controller. Make sure that the joysticks are connected before you go into the player selection screen because the amount of player slots that the screen will display depends on the number of connected controllers.

Additional Notes

Joystick support
The game requires at least one joystick to be connected. Since I had very limited time in building this game, I only pre-set configuration for PS3 controllers. You can try and play it with other controllers but it's unlikely that the usable buttons will be comfortable to use, and the axis may not even be configured correctly.

If you want to use a different controller, you need to add a new configuration in the gamestate.rb file, similar to the PS3 one:
PS3_CONTROLLER  ={horizontal: 0, vertical: 1}, {:horizontal => 2, :vertical => 3}, 11, 9)
Then use your new configuration instead of PS3_CONTROLLER when adding a new player to the player list:
@player_list.add(, rand(window.width), rand(window.height), p.controller_type == :joystick ?, PS3_CONTROLLER) :, p.vehicle, p.crosshair)

To find the correct button-mappings, use jstest.

Further info
I now plan to make other individual posts explaining some of the stuff I did, like Gosu Joystick support on linux, Health Bars with RMagick, Parallax scrolling, the Menu system and others.