Hi. I'm designing a computer game at the moment (it's still in the theory stages right now, since I can't get much done until I've got a working engine for it) -- I make 'ammateur' games as a personal hobby in my free time. However, my latest attempt is a bit more mathematically ambitious than my usual ones, primarily in physics. Unfortunately, I'm terrible at physics AND mathematics, so I'm hoping you guys can help me out with the formulae, etc. Basically, the game is a 2d 'sidescrolling' game. The player controls a spaceship in which they navigate the map from left to right. Simple. The problem is this: The player can customise their vehicle. Ultimately, they can choose from two types of chassis -- 'heavy carrier' and 'light skirmisher'. There are lots of different chassis you can choose, but they fundamentally come within those categories. Each chassis has various numbers of mounting plates, in varying locations, and varying numbers of engines, also in different locations (for example, the heavy vehicles would have engines on the underside to counter gravitational pull, whereas light vehicles have wings). You can buy parts for your ship (guns, shields, armour, etc), and these can be placed on any of the mounting plates available to you. However, each peripheral you attach has its own mass, and this mass SHOULD affect the physics. So if a heavy carrier with a massive gun turret on the top rear is speeding along and suddenly brakes, the back would lift a little. If the back is heavier then the front, then the rear countergravitational engine should have a much harder time keeping it up than the other end. That's my problem. Knowing how switching engines on/off, the varying masses and locations of the mountings, as well as gravity, the chassis' and mountings' inertia, and the thrust of the engines, would all coalesce mathematically. In short, I know nothing about physics. Basically, each vehicle has a point of rotation, it can rotate 360 degrees, it can move 2 dimensionally (up-down, left-right) only. An example of the kind of things I suppose I would need to know are the math to find out: .How the cumulative mass of the vehicle and all its mountings should affect decelleration. .How weight distribution would affect rotation (eg: A heavy rear end (no jokes would cause a rotating vehicle to swing around a lot; and making the back end lift/drop a little when slowing down depending on the weight distribution, etc) .How weight distribution, the thrusts of the various engines, and other factors, would affect the point of rotation. .How weight distribution would make one thruster have more strain than another, and force one end to 'hang' against the force of that engine. That kind of thing. Sorry if it's asking a bit much, but can anyone help out?