Level(value)Expresses the different constraint relaxation levels, which are applied for a visit and those that follow when it satisfies the threshold conditions.
The enumeration below is in order of increasing relaxation.
Values: LEVEL_UNSPECIFIED (0): Implicit default relaxation level: no constraints are relaxed, i.e., all visits are fully constrained.
This value must not be explicitly used in `level`.
RELAX_VISIT_TIMES_AFTER_THRESHOLD (1):
Visit start times and vehicle start/end times
will be relaxed, but each visit remains bound to
the same vehicle and the visit sequence must be
observed: no visit can be inserted between them
or before them.
RELAX_VISIT_TIMES_AND_SEQUENCE_AFTER_THRESHOLD (2):
Same as `RELAX_VISIT_TIMES_AFTER_THRESHOLD`, but the visit
sequence is also relaxed: visits remain simply bound to
their vehicle.
RELAX_ALL_AFTER_THRESHOLD (3):
Same as `RELAX_VISIT_TIMES_AND_SEQUENCE_AFTER_THRESHOLD`,
but the vehicle is also relaxed: visits are completely free
at or after the threshold time and can potentially become
unperformed.