TractionForce.X = PacejkaLateral(......);
TractionForce.Y = PacejkaLongitudinal(......);
This gives you the final 2D force vector you can contribute to the car body. I'm assuming the lateral is X, and the long is Y within the XY plane. Some tutorials have this reversed.
I guess I have to cap'em so they lie within the circle?[/quote]
Well, you don't have to. The whole point is to model car spins and other crazy out of control situations when you push the vehicle too far. In order for that to happen, you need to make allowances for the slip angle and ratio to map outside the traction circle. If you cap at the traction circle, then you are effectively flattening region outside the circle. This means that your slides will be consistently the same no matter how extreme are your slip parameters are. Of course it all depends what you want out of the game. Give either a test and use whatever feels good.
This is where having the Pacejka plots in a spreadsheet is so useful. You can easily manipulate its constants and try out different curves and slopes outside the peak traction.
