So! Starting in version 4.5 it is possible to add your own custom ships to the game! Yay!

The way it works is that you simply place images for the sprites and text file to describe the ship into the data/mods/ships/ directory.

Here's an example of such a ship:

{
name: Actual test ship
texture: startrek.png
uncoloredTexture: startrek2.png
description: To boldly go where no man has gone before
speed: 0.001
hitpoints: 2
width: 0.04
height: 0
supportBonus: 1
monster: true
weapons: [
	Spread Missile
	Dragons Breath:Blue
]
behaviour: Patrol
}

Supported weapons:

• Laser
• Weak laser
• Anti-ship missile
• Surface missile
• Spread Missile
• MIRV Missile
• Dragon missile
• Heal ray
• Disruptor missile
• Dragons Breath
• Chain missile

Take a look at the sample ship in the mods folder to get some more inspiration. Have fun!