It can be used in time when need do some tasks before
another movement generator add on top to motion stack.
This just finish pair Interrupt->Reset similar Initilize->Finilize
In general movementgenerator have states:
Initilize=>Interrupt<=>[-some addition movegen->]<=>Reset=>Finalize
To update a creatures distance to it's target without creating a new movement generator. Note it can only be used where creature is using TargetedMovementGenerator.
Signed-off-by: NoFantasy <nofantasy@nf.no>