Contango and Backwardation Calculations (Rolling contacts)

Does anyone know how the calculations between futures contacts work. (For my example I make assumptions just to make the example easier to explain like roll dates etc.).

Example on next two contracts:

100.00
100.11

Roll date is say tomorrow.

So overnight the broker will 'pay' 11 points (times contacts) to the trade balance?

That just seems too simple. Is that all there is to it?

you got it backwards, at expiration you sell your long contract at 100 and buy the next one at 100.11. And you gotta do it yourself, your broker wont do it for you.

The difference (0.11) is supposed to be the cost of carry (and it usually is for currency futures) -- however in physical commodities there are other considerations such as cost of storage and so on. Those considerations will in the end determine whether the chain is in contango or backwardation.