Variable Font Issue


I’m making simple variable font, and have issue with axis.
Axis a is a height of right part of P. (Image 1, 2)
Axis b is a position of inner white spot of P. (Image 3)

Is there way to avoid the conflict, when a is not high enough for placement of inner spot? (Image 4). Is it possible to connect height of a to positioning of white spot?

How many masters do you have? You might need one for a+b.