With @karenzshea's name / ref split (ref. #2857) in master we want to
make use of it and reduce `NewName` instructions when ever possible.
This is a first step towards #2744 by using the already existing name
change heuristic from the extractor now in post-processing as well.
Limitations: at the moment we don't have the `SuffixTable` in
post-processing; this would require us serializing and subsequently
deserializing the table, passing it through from the profiles to the
API.
Before we only worked on subsequent quick turns, as in:
`right, right` keeps the user on the rightmost lanes.
This changeset modifies the logic to work on any subsequent steps
that are "quick" and have lane information we can constrain later.
Because we do not have a from-lane => to-lanes mapping we take the
lanes left and right of the turn lanes into account when heuristically
assigning the leftmost / rightmost lanes.
There are some edge cases where this still does not give us the optimal
solution but it gets close to what is actually possible at the moment
without having a lane mapping in post-processing.
References:
- https://github.com/Project-OSRM/osrm-backend/issues/2625
fix rebase
https://github.com/Project-OSRM/osrm-backend/pull/2685/files
fixes an issue where we did
elongate(fstStep, sndStep);
instead of
newStep = elongate(fstStep, sndStep);
we didn't get any warnings.
The only way to trigger a warning here is to use
```cpp
__attribute__((warn_unused_result))
```
This changeset does exactly that: for the new guidance code prone to
these kind of issue we add such an attribute to the declaration.
This changeset implements Lane Anticipation on roundabouts, delimited
by enter / leave step pairs. It does not handle lane anticipation
within a roundabout.
Lane anticipation happens on the granularity of a valid roundbaout:
We discard partial roundabout (enter without exit or exit without
enter) or data issues (no roundabout, exit before enter).
Related:
- https://github.com/Project-OSRM/osrm-backend/issues/2626 for lanes
within a roundabout
- https://github.com/Project-OSRM/osrm-backend/issues/2625 for handling
going straight in lane anticipation
From
> [warn} oops
to
> [assert] /tmp/osrm-backend/src/extractor/extractor.cpp:79
> in: int osrm::extractor::Extractor::run(): false
> terminate called without an active exception
