Shaping point question

[Peobody]

I too get a sense of satisfaction out of "Getting it to work!" and the "it" can vary widely.

This is one of the potential lunch spots that I am trying to provide an alternate route advisory if there won't be a lunch stop. In this case we will be coming in from the south. That road is US-76. It briefly combines with GA-23 before heading west. You can see that I have a Via point (alerting) named "If no lunch stay on 76" followed by two shaping points and the restaurant point (all non-alerting). My thinking is that a right and then a left following US-76 will not cause any recalc related issue once we're back on the magenta line (provided no device auto recalcs). I think the alerting waypoint is too close to the intersection so will be moving that back a bit but otherwise, what do you think?

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[FrankB]

First of all not clear if you're asking me or John.

I really dont know if it would work. Suppose I was driving I would not understand "stay on 76". I would think: "I am not on the 76 now, so how could I stay on it?". But that could be my fault.
But provided you 'hit the via point', you can miss the via points without a problem. Maybe you have to 'fix the trips' with the Java program, or any of the other options.

I do see another potential problem, totally unrelated to your question. But in the past I had problems with routes that forced me to make u-turns. More specific the 'Closest Entry Point' would be unpredictable. It would sometimes work, sometimes you would get a totally messed up route.

But i'm interested in the matter, so keep me posted please.

[Peobody]

First of all not clear if you're asking me or John

Both. I know that one of John's concerns is that the XT will rename the instructional via points. I have not experienced the rename phenomenon, or if I have, it when unnoticed.

The more I think about this the more I don't like it. I think it would work if it was used solely by me, but not for a group ride. The restaurant point, as a non-alerting point, would not provide a clue to other riders about what it is. It will appear as a misplaced route point. I'm dropping the idea.

[jfheath]

Here's how I think that route will play out.

I am assuming that both points were created as Waypoints - unless you changed the symbols in BAsecamp yourself.
Not that it matters as far as the route is concerned - only that the name will change. This behaviour happened on units with Foursquare - which is probably just coincidence - so the 595 and XT. Not the 590.

Approaching from the south, the blue flag is a Via point, so it will announce something like as you approach 'Approaching If no lunch stay on 76' on the left'. No problem, pass through it.

It will then show an turn left warning up ahead onto route 23. You ignore it and decide to take route 23 north ?

The satnav will recalculate another way to get to the D2 Sunday Diner - but whichever route it takes, it will have to pass through the other two points - one just after the left turn onto the route 23. One following that after the turn west off the route 23 to the Diner.

You carry on towards the point where you disappear off the top left of the screen. Possibly by taking the 23 north, and then the 76. Possibly by taking Old Livery Street north and then right onto the 76. All of the time the XT will be finding ways to get you to turn back to thta first missed shaping point.

Eventually you will join the magenta line on the 76, where it turns left from vsiting the diner.

You said the diner was a shaping point. If that is the case, and the others are shaping points, then the route will calculate ahead as soon as you join it.
If any of those three missed points were Vias, then the satnav will still be trying to get you to go back to that first missed shaping point on route 23.

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The renamed route points never happen if they are created as waypoints.
If they fdo happen - they usually come up with sensible names that you may well recognise.
I notice the change becasue I tend to put 3igit sequence (mileage) numbers in front of my names.

Typically, an unchanged route point name will have lat/long coordinates underneath the name.
Changed coordinates will have a road, town, Postcode, county code (any of those) after it.

This is noticable in the UK eg Penrith, CMA. It took me ages to work out what CMA was. It turns out that we have 3 letter codes for each of our counties - like USA has for states. I didn't know that. I have never seen them used before. Perhaps Google made them up ?
SO these changed names stand out like a sore thumb for me !!

[Peobody]

Thanks John. I think the key is whether the satnav recalculates. If if is not allowed to then all should be well once back on the magenta line heading north offscreen (route 76).

Expecting riding companions to recognize what I did is a big ask. I am hoping that we will all be in communication but that is not a given since there are two Cardo's and a Sena. Regardless, there will be a leader, and all three are skilled at manual navigation, so the only concern with skipping a Via point lunch spot is the potential recalc mayhem resulting from the required Skip of that Via.

[jfheath]

Just coming back to this and adding a note for anyone else reading this a few weeks down the line - as I have just done...

If you have auto recalculations turned off, then when you deviate from the route, the satnav goes quiet. No instructions.

If you then rejoin the magenta line, normal spoken navigation continues - unless you have missed out a via point. If you have then one of two things will happen...
1. The satnav will remain quiet, even though you appear to be on the magenta line. This is because you are heading in the wrong direction - the satnav is trying to get you back to the missed Via Point.
2. The satnav will keep trying to turn you back. This is not RUT behaviour. It is correctly trying to take you back to the missed Via Point.

Odd, but entirely logical behaviour occurs after deviating from the route, just before you are about to rejoin it - having missed a shaping point: As you approach the magenta line crossing your path ahead of you, the missed shaping point to your right, the way ahead to your left. The satav may notice the route ahead and tell you to turn right- to reach the missed shaping point. You need to turn left, and it will immediately realise that this is the way ahead.

This can cause issues at roundabouts, as you could hit the magenta line leading back to the missed shaping point before you hit the one that heads in the direction you want to be heading.. This can happen whether autorecalc is on or off, but in different ways. It is always worthwhile before rejoining a route at a roundabout, to work out which magenta line you will be taking so that you continue heading in the correct direction, because the satnav may issue the instruction to take you back to the missed shaping point part way round the roundabout.

[Fxwheels]

It is always worthwhile before rejoining a route at a roundabout, to work out which magenta line you will be taking so that you continue heading in the correct direction, because the satnav may issue the instruction to take you back to the missed shaping point part way round the roundabout.

That is right. You always need to know which direction you're heading. Just by zooming out and see where the main line goes. Of course should be done with safety in mind as all these inputs are diverting attention from the road.
I normally have auto recalculations on or prompted. Still you have to be always in control of the route.