This describes the process of building a game-balanced ship, based on my current ramping.  With the exception of very large ships (which need considerable physics tweaks to behave at all naturally), this process will give you game-balanced ships- basically, smaller ships turn faster and accelerate better, but have less Power available for guns and shields.  With the Shields eating more and more power at the top levels, this more-or-less evens out.  

My XML Power Generators mod is in this codebase to demonstrate how Power Generators can make or break your game design- in the case of this one, the high-level ones make the ship balancing-act almost worthless... game-designers, go playtest what a Dagger with Class 10 everything + Power +500 is like ;-)

PHYSICS

MASS

Reference Mass = 100.  This goes up or down, depending on the following factors:

100 + 1 for every 100 points of armor over 1000. A fighter with 8000 hitpoints, therefore, weighs 170.  This includes subgroup hitpoints!

TORQUE ("turning speed")

Torque references go up or down, depending on the following factors:

20 X (Mass - 100)

Standard... Mass 100- everything goes *down* from here, to a minimum of 1000.

steering_torque = 17500, 17500, 17500
angular_drag = 10000, 10000, 10000
rotation_inertia = 1000, 1000, 1000

Therefore, a fighter with a mass of 250 has stats like this (or a multiple, for things that can turn quickly but where we want them to have "stiff" collision behavior):

torque = 14000
drag = 10000
inertia = 1000

Things with really super-high Mass should add 3-5 zeroes to the ends of everything, and multiply drag by at least 1.5... and intertia by 5 or more.  Battleships and other large vessels look extremely lame if they can switch vectors like a fighter can ;-)

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POWER

Charge Rate = (Mass - 100) * 3 + 100, minimum = 100.  Therefore, a ship with a mass of 250 would have a Charge Rate of 550.
Capacity = Charge Rate * 10 + 1000.  Therefore, a ship with a mass of 250 would have a Capacity of 5500.
