This change takes the existing typedefs for weight, duration and
distance, and makes them proper types, using the existing Alias
functionality.
Primarily this is to prevent bugs where the metrics are switched,
but it also adds additional documentation. For example, it now
makes it clear (despite the naming of variables) that most of the
trip algorithm is running on the duration metric.
I've not made any changes to the casts performed between metrics
and numeric types, they now just more explicit.
Weight and duration penalties are flipped in the lambda function
that applies penalties from traffic signals.
Duration is in deciseconds, whilst weight is multipled by
10^weight_precision, with weight_precision being 1 by default.
Therefore, for default routability profile, the penalties end up
being the same, hence why no tests picked this up.
If distance weight is used however, it will incorrectly apply an
additional penalty to the weight, and not add the traffic signal
delay to the duration in the routing graph.
To confuse things further, in some API responses the values are
correct because they use geometry data instead, but it's still
possible that a sub-optimal route was selected.
However, given the distance weight is in meters, and the additional
penalty per traffic light would be 20, it's unlikely this would
have changed the routing results.
In any case, we correct the function to apply the arguments correctly.
In case we're not able to get access to the unscoped credentials.
Scoped packages are also the recommended approach for projects
managed by a team of developers.
Badly constructed OSM intersections can create OSRM intersection
views that have no valid turns.
The guidance code for segregated intersections tries to look
ahead to the second intersection to ensure lanes are announced
intuitively.
Currently, OSRM assumes there are always turns at the second
intersection that we should consider. This commit corrects
this assumption so that it can now handle badly constructed
OSM intersections with no turns.
Due to some rather complex logic that tries to calculate intersection
angles by looking further up the road, it's possible to return
an intersection view that is missing a u-turn - something which
is assumed to exist in later guidance calculations.
We apply a fix here by ensuring the u-turn is always included in
the returned view.
