Fighters and drones are mobile DPS platforms. You cannot fully simulate how they apply damage. Pyfa exposes control of that via extra menu:
Stick to target - drones always take target's position. IIRC this is default setting since it's how pyfa behaved until graphs were reworked.
Stick to attacker - drones/fighters are placed into center of attacking ship/structure and are forced to attack from there. The note regarding center is important to remember, since the distance shown on graphs is overview distance (surface-to-surface) and radius of some attackers is huge (supers, structures). Effectively it means that in this mode, range shown on graph is range of drone minus radius of attacking ship/structure plus radius of attacking drone/fighter.
Auto - if drones are faster than attacker, same behavior as stick to target, otherwise same behavior as stick to attacker
If you have any thoughts on how to handle it better - feel free to share.
DPS graphs of fighters apparently aren't taking range or tracking into account at all?
To reproduce: load any ship that uses fighters, add fighters to fighter bay, ctrl-g, observe flat dps graph