⟨11charon_s.⟩ Due to my friend himīśā is unable to login to discord, I'll pass messages on both sides:
himīśā reply to sichelgaita:
 Yes I mean gravity force by "geopotential model" because by this term I mean everything that related to the non-relativistic gravititional field related to a non-point mass center body.
I said k=2 means Newtonian gravity to ensure that I am talking about gravity acceleration field, not specific potential energy.
So No Discontinuous of force at Rmax.
If you want to do it correct, I also gave two ways to do them... But they require tons of coding and is too intensive for a GAME.