Currently we don't route over the Golden Gate bridge by default.
This sets the value to false by default. To test the behavior for
tolls when ignored, we would need issue #2781 implemented.
Roundabout Intersections are roundabouts with up to four ways and turn
angles which makes the turns obvious, e.g. as in:
```
*
*
* * * *
*
*
```
but not
```
*
*
* * *
* *
* *
```
For Roundabout Intersections we issue instructions such as
"turn <direction>" instead of "take the <nth> exit".
At the moment we have a limit on the radius for these Roundabout
Intersections of 5 meters. Which fails to classify a wide range of
Roundabout Intersections in the US (with the US-wide streets).
This changeset removes the Roundabout Intersection radius limit:
- if the roundabout is larger than a threshold and is named we classify
it as a rotary
- if the roundabout matches our criteria for Roundabout Intersections
we classify it as a Roundabout Intersection
- else fallback to plain old Roundabout
There is a second issue with determining a roundabout's radius.
But that's for another pull request (tracking in #2716).
References:
- https://github.com/Project-OSRM/osrm-backend/issues/2716
Staggered intersection are very short zig-zags of only a few meters.
They are common in rural and exurban areas, especially in the US.
(In addition, these cases could as well be tagging issues)
We do not want to announce these short left-rights or right-lefts:
* -> b a -> *
| or | becomes a -> b
a -> * * -> b
Here is one example:
- https://www.openstreetmap.org/edit#map=20/39.26017/-84.25182
And here are two edge-cases that we don't handle at the moment:
- http://www.openstreetmap.org/edit#map=20/38.87900/-76.98519
- http://www.openstreetmap.org/edit#map=19/45.51056/-122.63462
and probably should not handle since the distance in between is
quite long (roughly 7-15 meters). For these we want to announce
two turns to not confuse the user.
Thanks to @1ec5 for raising this issue and @karenzshea for
providing additional US examples and cultural insights.
Why only `hov=designated` and not all access tags, such as `hov:yes`,
`hov=no` and so on? From the Wiki:
- designated: The way is designated to high occupancy vehicles.
- yes: High occupancy vehicles are allowed. This by itself does not imply that other vehicles are restricted from using the way.
- no: High occupancy vehicles are not allowed on the way. This by itself does not imply that other vehicle types are allowed to use it.
The primary use-case is conditionally filtering ways such as:
http://www.openstreetmap.org/way/11198593#map=19/37.82571/-122.30521&layers=D
In addition there is a notion of HOV lanes for lane handling:
http://wiki.openstreetmap.org/wiki/Key:hov#hov:lanes.3D.2A
This changeset does not handle lanes at all, only designated HOV ways.
For HOV lane support, a logic similar to the lane access handling needs
to be implemented. This needs to go hand in hand with the existing lane
handling introduced in:
7d076e9344
References:
- #2711
- http://wiki.openstreetmap.org/wiki/Key:access
- http://wiki.openstreetmap.org/wiki/Key:hov#Values
After half a day of looking at the tagging and the data came to the
following conclusion:
We can't keep the user to the innermost / outermost lanes depending on
the exit the route takes: we found situations where both heuristics were
wrong.
Even on popular roundabouts the tagging is often wrong or in the best
case not present at all.
There are at least two different ways to interpret roundabout
indications: 1/ where e.g. a right arrow on the lane indicates turn
restrictions for the roundabout and the need to take this lane to exit
the roundabout to the right (possibly skipping multiple exits) and 2/
where a right arrow just means this is a lane in a immediate right turn.
Example: Australia marks lanes with arrows that seem to indicate
"angles you can exit the roundabout from", for example, these two ways:
- http://www.openstreetmap.org/way/320941710
- http://www.openstreetmap.org/way/42918021
Whereas Germany marks lanes with "directions you can travel in these
lanes immediately after entering the roundabout":
- http://www.openstreetmap.org/way/52578338
These two different interpretations of how to draw the arrows on the
roads mean we have conflicting solutions to "which lanes can you use to
take exit B from entry A" based on locality.
Continuing to tag ways based on lane markings is no problem, but
unfortunately, we can't reliably resolve good advice for navigation
system users (like "use the inside lane to take the second exit at the
roundabout"), there are too many situations that would generate bad
instructions (instructions that tell users to go into a lane they
shouldn't use).
Before we asserted on unique lane indications per lane. Turns out the
OSM data contains lane strings such as:
left;left|right
Which represents two lanes as in:
<< >
|| |
The two left indications _on a single lane_ look like data issue.
And we can't represent this with our enum-approach at the moment.
We don't want to crash there, so silently swallow this and
generate a single left|right for it.
