How does affinity grinding work? I know you have to win g1 races for more, but I'm getting a lot of different info online. Is it the total combination of shared g1 wins between:

>sub-legacy 1 and legacy 1
>sub-legacy 2 and legacy 1
>legacy 1 and legacy 2

or is it

>sub-legacy 1 and sub-legacy 2
>legacy and both sub-legacy

also, is it 1 point or 3 points per shared g1 win?