Tread Changes Exisiting Routes - Shaping Point Issues

[proofresistant]

I'm glad that I have good, quickly comprehensible examples based on my _Tread_Shaping_Point_Issue_Guide

Inspired by your last comments, I have now completely ignored my XT2.

Test 1:
Imported the "rt_WK_Tyre_BCcalcCN_11_ShpPts.gpx" (route with shaping points) directly into the Tread app
Result 1:
Immediately (very quickly) the sharpening points were shifted

Test 2 Step 1:
imported the "rt_WK_Tyre_BCcalcCN_11_ViaPts.gpx" (route with via points) directly into the Tread app
Result 2 Step 1:
Everything looked fine.
Test 2 Step 2:
rt_WK_Tyre_BCcalcCN_11_ViaPts.gpx manipulated by me in the Tread app.
I converted all via points from the end to the beginning into sharpening points.
Result 2 Step 2:
With the first changes the sharpening points were slightly shifted and with the last change (first of the route) the route was clearly changed.

I hope this helps.

PS
Manipulating the routes in advance as my route planning task in the Tread app until they work is definitely not a reasonable option.

PPS
I can live with the fact that BC is no longer compatible with the XT2 or tread app, as BC cannot, among other things, generate different route algorithms between the VIA points.
But the XT2 or Tread app at least has to support GPX files, no matter where they come from and in principle no matter which maps they are based on. As far as I'm concerned, XT2 or Tread App should recalculate, but leave the via or sharpening points as they are.

[proofresistant]

So, I now have a second example to try out with the route “rt_NL_Rat_BC_ShpPts.gpx”.

This “rt_NL_Rat_BC_ShpPts.gpx” also reliably causes me issues in relation to the Tread app.

In the example, I can't even open this route in the Zumo XT2 when I import “rt_NL_Rat_BC_ShpPts.gpx” via the Tread app
After the route has arrived in the Zumo XT2 via the Tread app, I can't even open it in the Zumo XT2. After opening it, the screen hangs with the message (freely translated) “Route is being calculated. 0%”.

If I import the same route “rt_NL_Rat_BC_ShpPts.gpx” via SD card into the Zumo XT2, the route can be opened and calculated in the Zumo XT2 without any problems.

It is noticeable that this route, even if it works perfectly in the XT2, then also appears in the Tread app, where it can also be opened, but cannot be used / calculated as a route there.
However, the fact that the tread app cannot calculate the route has the added benefit that the tread app cannot destroy it either

[jfheath]

Thanks - So just so I am reading this correctly.

"When you import it Via the Tread App" - Does that mean that you import the gpx file as it is - using the option in the tread app to load in the gpx file?

[proofresistant]

sorry,
sometimes my English is misleading
I share the route with my smartphone and select there, open with Tread App.

[jfheath]

OK - Thanks for posting that.

I spent all morning looking at your GPX file, trying to work out why it wasn't working and trying different scenarios.

And I have an answer for you. Drum roll .......... I haven't got a clue.

Let me expand on that. I thought - I'm going to record this - so I set up my phone with its screen displaying on the computer monitor (and can be operated using the mouse and the keyboard), and I set up the XT2 in itse cardle with a video camera - set up the screen recording software to record everything I did.

Before doing anything, I Loaded the route into Basecamp and created a track from it.
Then I took a close look at every shaping point. Some were in positions where they were slightly off roads, badly placed on the wrong side of a juntions - so I corrected these. THe very last point is bypassed by the route - and the route goes past it, up a side road and then approaches it from the opposite direction. I think the mapping believes that to be a dual carriageway. It isn't, but it had been a very short distance before. I checked it on Street View.

I modified the GPX file to remove some route points that the XT2 might find difficult to deal with. Slightly off route. That mad little difference.

The Route placed on the SD card would not calcuate. Later on in the day - it did. I don't know how. I was recording what I did, so I need to trace back to find out when this happened.

The route transerred to the Tread App by importing the GPX file didn't do anything for ages. It would display shaping points and a dotted straight line point to point route. IT never calculated that - but I realised that it would load into trip planner. I selected the segement and asked it to calculate faster route. That produced the required maganeta line - but the route didn't quite match the track. Some shaping points had been moved to match the new route in somr rather odd places. So it is the Tread recalculation that causes the issue ?

This did not match my previous experience. The route was copied exaclty as it was and I couldn't make it change but I didd not recalculate it.

The shaping points were in the correct position when they were joined with straight dotted lines.

I wonder if the detailed description of the route and the subclasses makes a difference. BAsecamp cannot produce a route without subclasses. But MRA can. I'll give that a go.

[jfheath]

Ok - more progress.

I started putting Via Points into your route - changing shaping to Vias in Basecamp and re-exporting them. I changed 9, 11, 18, 23 to Vias

The route plotted on the Tread app to Point 11. ANd it plotted OK from point 18 to the end. I had p[reviously tidied up some route points, including the end, which was on the wrong side of the road - the map clearly thinks its a dual carriageway at that point, even though it isn't.

In between 11 and 18 the route was plotted as dashed straight lines, So I started looking at the map more closely between 11 and 18.

Points 12 and 13 are plotted on a road which is not open to cars and motorcycles - according to Street View. So I deleted those two points.

There are some other issues around that are too. When I changed the other Vias back to shaping points the route would not draw again. So I guess that at least one of 14, 15, 16, and 17 may be suspect too.

I've run out of time, I'm afraid. But this appears not to be the Garmin issue that we have been looking at !! I can get a result by recalculating the route. eg changing the route profile for another (Adventurous 1, and then back to Faster time) - but that causes the shaping points and route to shift.

We just need to know what it is about this route that prevent it from plotting a route through the shaping points. So far, all of the above has kept the shaping points in the correct location.

[proofresistant]

Yes, the route is special,
but it's a good example with roads just as small as the ones I like to ride here.
Whether the roads are closed to “everyone” shouldn't matter, you have reasons to want to drive exactly that way.
I know you can sometimes avoid such problems by using VIA points. But honestly, what does Garmin want from me? I plan a route and Garmin doesn't like it. If there was at least a hint why it doesn't like such routes, or a choice to ignore it, but no Garmin can't and that's that.

Then, here's the very interesting point, if the route is copied via SD card, the XT2 is apparently much more likely to cope with it.

[jfheath]

Then, here's the very interesting point, if the route is copied via SD card, the XT2 is apparently much more likely to cope with it.

Not from my observations. Your route would not calculate by the XT2 when placed on the SD card

When imported i to the tread app, it didn't calculate, but could be forced simply by selecting the segment and choosing / rechoosing a preference. But that moved the route and shaping ponts - although it followed much of the original pretty closely.

For me, normally a route placed on the SD card is ok if it cannot synch the Tread app. If it does, it changes - not completely, but some.

For me so far, If I import a route gpx file i to tread, the route remains intact and is synch'd intact to the XT2. I haven't followed a route like this on the road yet.

[proofresistant]

It's strange that it works for me when I import via SD card. The different behavior only makes it even more mysterious.

As I wrote, I tried the route again with exact points. Imported via SD, this route was also OK in the XT2, no better and no worse than before.
Only the Tread app had different results, just not good ones, and the one imported from the Tread app could be opened, but gave the error “Calculation not possible”.



Then to the accuracy of the points.
The points were already "nearly" accurate.

If about 5m is already a problem, then a lot of people will probably have a problem with that.
Then the device should be able to handle a certain margin of error.

However, like you, I set the points as precisely as possible and the result was somehow different, but unfortunately not significantly better.

Then to the sides of the road. We'll probably stumble over this more and more in the future if the navigation systems can't handle it. There is already more and more map accuracy where 2 lanes are recognized, even in cities with slight divisions or wide streets.
If you're not careful and the sat nav doesn't assist you, you end up driving in large circles. It also gets exciting when you simply want to turn existing routes in order to drive them back in the other direction. Have fun if the navigation system can't help you.
Such situations are best recognized by large screens, not good on the device and also not good in the Handy Tread app. This makes it all the more important that a planning software supports this and that the import of externally planned routes is reliably supported.

[jfheath]

I couldn't understand the very different behaviour with this route from @proofresistant - especially since it punched a gigantic hole in theories that I had formed from my previous tests - so I needed to find out: Was this completely new behaviour, or was it something particular to this route. Hence I made sure that every single point was on a road. Some weren't. I didn't think that this would make the slightest difference - but since I don't know how Tread behaves, I made sure.

It turned out to be the route. Goodness knows how it was created - the track and the route did not quite coincide on the Basecamp map (2025.1) that I was using - so BC had not created the track. And I do not understand how a BC map can come up with a route with these issues. Mine would not let me plot a route along the track that came with the route


The green section below is a stupid user error on my part. My recalculation of the route to ensure maps matched involved applying some avoidances that had somehow been set in my Basecamp options. The 'not a crossroads' comment was due to my BC not wanting to take it and a quick look at Google maps - which I took to be a flyover. The road works and prohibited routes are correct - but no longe an issue as BC was happy to route down them.
So Apologies for finding stuff that wasn't there and stuff that was there, but not relevant !

There were four issues and one still unresolved:

• A turn at a cross roads was not a cross roads - it was one road passing over another.
• A turn onto a main road was not available. A turn off the main road was available, but not onto it.
• One road - BC would not navigate. On street view it is a coned off one way route - due to road works. The way that the route goes, but it is probable then that the road was either closed, or was one way in the other direction at the time the map was created. Whatever - the Basecamp map cannot draw a route heading south. IT can draw a route heading north, but street view says is is closed in that direction. So (like the top of alpine cols) there has been a long term semi permanent closure. Maybe it will be different when I install the 2025.2 maps.
• One road was marked as prohibited to vehicular traffic - google street view.

So it turns out that there was nothing new to investigate here.

But it did emphasise some other issue which I am still looking into. Mainly - why does it sometimes plot a straight line, dashed route on the Tread App.

In other words - I found things that were casueing the routeing some problems. I didn't find the answer to the whole route itself. THe only thing I didn't re-draw was the start point. "When you have eliminated all which is impossible, then whatever remains, however improbable, must be the truth". The Via Points carry with them all of the routing details for the next segment. Or the maps are out of synch. Maybe time to update my map. I'll try that first.