[Script] WME Validator 1.1.19 / 04.06.2016

[sketch]

A bowtie U-turn is not too sharp.

Validator does not report too-sharp bow-ties. But this intersection is not a bow-tie.

Have a look at the Classification of crossings, DSSS:

you may want to join the double lanes into a single node, creating a sort of half-mapcat-bowtie

If you do so, Validator will detect the "half-mapcat-bowtie" and will not report "too-sharp turn". Alternatively, you can make the turn more than 30 degree or just ignore the warning.

Sure, Validator can look for similar street names, but I guess it will eliminate any use of this check, because the check basically was designed to detect situations like this...

Right, that's not really a bowtie, it's simply the point where a road transitions between split and un-split. For every situation where this happens at an intersection where U turns are allowed, there are several which happen somewhere along the road and where U turns are certainly not allowed.

As an aside, wow, that Wiki article could use some work! Lots of what-not-to-do screenshots and no corresponding how-to-do-it-right screenshots, just brief bits of text that even I have a hard time understanding. Needs some right-way-to-do-it examples and some big red Xes on the "don't do this" examples.

[dknight212]

In London we use this type of construction to work the time based operation of our congestion charge.[...]is it possible to prevent these types of segments being raised as issues?

It's not a problem to suppress the "Overlapping segments" either for lvl 6 locked segments or if one of the overlapping segments has a time based restriction.

Please note that Validator users have the "Exclude non-editable segments" option set by default, so low-level users do not see those errors since the segments have lvl 6 lock.

Please discuss the options I mentioned above with the other CMs and let me know shall I exclude lvl 6 locked segments, segments with restrictions, both or neither.

Thanks!

Thanks for this, unfortunately no great demand from the other UK CMs for this. I wonder if it would ever be useful to have the ability to select only certain lock levels for checking? I suppose not, given that an error is an error whoever caused it. Oh well.

[AlanOfTheBerg]

As an aside, wow, that Wiki article could use some work! Lots of what-not-to-do screenshots and no corresponding how-to-do-it-right screenshots, just brief bits of text that even I have a hard time understanding.

Maybe just edit it to redirect to the Junction Style Guide page?

[sketch]

Maybe just edit it to redirect to the Junction Style Guide page?

Not without adding some of the content to the Junction Style Guide. I'm only now noticing that the Guide doesn't actually include guidance on split-road intersections besides the bowtie. The section should be renamed more generally, and the information in the "classification" article should be modified for inclusion into that section of the JSG. I'd also want to contact fvwazing and ask if the classification names are actually used in any context before removing them from the Wiki.

I'm short on time today, otherwise I'd make a Wiki update thread about it. If you want to do that so we can stop hijacking this thread about it, that'd be cool, and I'll get to it when I can (hopefully tomorrow). If not, I'll do so when I have the chance.

[dbraughlr]

Validator does not report too-sharp bow-ties.
...
Sure, Validator can look for similar street names, but I guess it will eliminate any use of this check, because the check basically was designed to detect situations like this...

Yes, this is just a transition from divided to undivided. I thought that it was a simple case for demonstration. I didn't know that you had logic to detect an intersection.

A transition like this is valid and should be permitted.
What error would ever be missed by permitting this specific configuration?

[berestovskyy]

What error would ever be missed by permitting this specific configuration?

The main purpose of the "Too sharp turn" is to detect such the situations. Here is the original proposal by robindlc: this thread link It comes handy for connectors on intersections. For instance, left turn from the connector should not be enabled here:

As in many other situations.

You have few options:
1. Disable the u-turn.
2. Make the u-turn at least 30 degree (i.e. less than 150 degree of course deflection).
3. Split the road right on the intersection (i.e. make a half-bowtie).

Any of the above will make the Validator happy.

[dbraughlr]

1. The U-turn must be allowed.
2. Widening the U-turn could give rise to "Stay right" instructions for traffic going straight through.
3. Moving the split will result in Missing Road MPs when drivers make the legal U-turn.

Regardless, the example you gave doesn't match the transition scenario at all and would be detected because of either:

1. The junction does not have a two-way street splitting into two one-way streets departing at less than 60 degrees from the two-way and within 90 degrees of each other. Or,
2. The names of the one-way lanes do not begin with the name of the two-way street.

An at-grade connector is a one-way street that is usually unnamed. The duplicate right turn on the two-way portion should be disallowed.

[sketch]

What category is "too sharp turn" now?

If a distinction can be made between at-grade connector too-sharp turns and transition too-sharp turns, then the former should remain as a "warning" or whatever and the latter should be classified as a "note". I agree that there are allowable instances of this, but I must say that since the check was introduced, I've corrected dozens of instances of this mistake.

If not, the whole thing should be a note, I suppose. But it should definitely not be removed.

[berestovskyy]

2. Widening the U-turn could give rise to "Stay right" instructions for traffic going straight through.

I guess not, please see How Waze determines turn / keep / exit maneuvers

if s-out is determined to be the best continuation of s-in, the instruction is: 'CONTINUE'

Since "straight" and "u-turn" directions both have the same name and road type, the "straight" will always be the best continuation because the angle is more straight. Assuming the wiki document has no mistakes...

[dbraughlr]

As long as we are quoting the wiki:

NOTE: Be aware of the geometry used in the bow tie. If the angles are too steep (45 degrees or greater) a driver traveling along one of the one-way segments may be told to "turn" or "stay" at the intersection instead of receiving no instruction.