Two-way Ramps vs. Routing [Split from WME Validator]

[CBenson]

I'm not sure what "the error" is. Seem to mostly be a display problem with the routes shown in URs as discussed for example here and here. It may actually effect the user when the endpoint of the route is on one of the two segments that connects the same two junctions.

Your post, the second post, in the first thread you linked shows a user that followed the "display bug" route rather than the TTS route. I don't think it's reasonable to consider something as important as the route line being displayed incorrectly is so minor as to be considered merely a "display bug". Especially when the user isn't using sound. Is the user more likely to follow the arrow in the corner, or the route line on the screen?

Understood. But I've never actually been able to get confirmation from a user that they were actually following the route line in a conversation on a UR like this. I certainly can't say it doesn't happen, just that I haven't been able to verify it. On the other hand I can say that sometimes the purple route line in the UR is not the same as the purple line in the client, because that has happened to me. Notwithstanding, I think it is worthwhile to add the extra junctions at this point.

[CBenson]

It may actually effect the user when the endpoint of the route is on one of the two segments that connects the same two junctions.

This is one of the main issues with the "same endpoint" that affects end-users directly. The routing server may start the user on the other segment instead of the one the car icon is sitting on. To my knowledge, this bug has not been fixed in the server/app.

Agreed. Another is that waze may not recalculate the route if you deviate onto the other segment.

[CBenson]

What's recent? I've seen it in the past three months. Not sure about the past two months.

Issues with two segments connecting the same two junctions goes back to the Cartouche days where the waze error codes could be solved by adding junctions to make sure that the same two segments didn't connect the same two junctions. Unfortunately waze staff has variously at different times told us that the extra nodes are not necessary and also told us to add them to "loop" roads to solve routing issues. There is additional discussion here, but its not so recent either.

[CBenson]

People say that the "same endpoints" error is real. I am on the side of excluding the validation until it is shown that it is a still real problem, especially since the solution seem to be to insert an unneeded node node that will have to be removed after the bug is solved.

It is a bug known to many. There have been multiple threads about it. I can't find them because they were started without an understanding of why Waze was giving such bizarre routes (because we figured it out using those threads). I'm trying to find them now, but I don't know if I will. If you're not willing to take a few champs' words for it, I don't know what else to tell you.

I'm not sure what "the error" is. Seem to mostly be a display problem with the routes shown in URs as discussed for example here and here. It may actually effect the user when the endpoint of the route is on one of the two segments that connects the same two junctions.

[CBenson]

Question: In cases such as those, wouldn't it just make more sense to make them two-way streets until get to the point where it actually splits into on/off ramps attaching to the freeway? Is there a reason why that stretch of road segment must be type ramp?

Not sure they have to be ramp, but they shouldn't be streets. If not ramp, they should be typed at least as high as the lower of the types that they are connecting so not to interfere with the long route pruning routines. But, ramps usually just look better to me in those examples to me.

[CBenson]

I don't see why a ramp should be split just because its a ramp. For instance, I don't see why the two way portion of a trumpet interchange shouldn't be mapped with a two-way ramp segment. But eventually they all seem to get edited to two one-way segments.

[Bobthedog007]

Me, personally, my concern here is that it could very well be one of those things where at one time it was, in fact, a problem. But now it may not be; they may have fixed that issue. My question is: Have there been any recent examples of this being a problem?

I came across this bug in the last few weeks on a route I often take.

There is a road that passes a fast food drive through and a small loop around the building for the actual drive through, causing the same endpoints problem.

I would drive down the road and turn left onto that small loop and then wait. I would try to route to my next destination from there which would require me to turn right from the loop back onto the road back the way I came.

But waze would insist on only turning left off the loop onto the road, sending me far out of my way and doubling back much further down the road instead of just turning right to get onto the road.

It seemed as if waze was determined not to route me across a segment when I was on the other segment that had the same endpoints.

This happened every single time I went there. I then went and edited it by adding a new node on the loop to see what happened.
Since then it has always routed the much saner and shorter route by turning right from the loop back up the road.

So this same endpoint segment problem is still present it seems and adding a third node definitely fixed it in this case.


This is the loop
I would come from the east then turn south into the loop.

[AndyPoms]

I just saw this thread...

Recently (last few months) there was a problem with two-way sections of ramps not giving the proper instructions - missing keep right/left on splits, missing turn right/left to enter/exit the ramps. All these problems were solved by removing the two-way sections of ramp.

[AlanOfTheBerg]

Notice the lack of the "keep left" instruction onto the freeway.

It's because the angle wasn't steep enough at the time. Now it does do as you'd expect and say "stay left".

I don't think any angle would give a stay left instruction if the two segments in the permalink were ramp segments. The road type continuity would make the ramp to the highway the best continuation and suppress the instruction.

It shows a stay left in livemap instructions.

[AlanOfTheBerg]

Notice the lack of the "keep left" instruction onto the freeway.

It's because the angle wasn't steep enough at the time. Now it does do as you'd expect and say "stay left".