You can't have a custom cost function, BUT the cost function can integrate:
- [mandatory] The sum of all arc cost used (used by any initial first strategy)
- [optional] The global span cost of any dimension (e.d. one coefficient per dimension, default 0)
- [optional] A vehicle fixed cost (e.d. one cost per vehicle, default 0)
Misc/Not tested yet:
- [optional] Soft constraint a group of node to be visited by the same vehicle
note: You can search for "soft" which means add extra cost to objective if not fulfilled while hard constraint must be respected...