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Guidance to next trackpoint, not nearest point

Haruki Yamada shared this question 8 years ago
Answered

I aware that other people asked a similar question before, but I amnot sure whether the solution exists or not; asking here again.


When I set "Guidance" to a route, a line with the indicator of distance stretched between my position and the nearest point on the route, but I prefer to point the next trackpoint.


Here is my understanding of points and trackpoints:

points: location info automatically added along the route

trackpoints: location info that user clicked on the map (while creating a route)


In my use case (for hike), I set trackpoints to some meaningful locations, such as junction, peak, col, etc., and I donot see much meaning of each point.


If I remember correctly, Locus behaved as I expected but at some point the guidance line starts pointing to the nearest point. Are there any way to have a guidance line to the next trackpoint?


I am using LocusPro 3.17.0, on Xperia Z1f (SO-02F, Android4.4.2).


Haruki

Best Answer
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@Haruki Yamada. I've made some tests. See in the zip attachment because to long to publish here.

In the .zip see .txt and used test sample gpx file

Replies (3)

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Your points are usually referred as trackpoints ( see e.g,. the serie of trackpoints in GPX files ).

Your trackpoints is usually referred as viapoints ( usually set in Navigation or Guidance dialog, or clicked/dragger in an online planner ). But if you generate your track online and use the final GPX, there is probably no distinguishing between both. TCX is probably another story, but I do not use them.


It seems to me you are using in some sense a kind of hybrid of Guidance(no navigation instructions - just guiding) and Navigation(track generated by routing engine with usage of viapoints), as you say points: location info automatically added along the route ).

If you use Locus PRO ( as Free version does not have automatic recalculation ) - What about using the Navigation instead, autocalculation=point priority ? In such case, if you go off-the track and trigger the off-distance threshold, the route is recalculated to the next viapoint ( if exists ) or the destination ( if does not ).

the limitation is, Navigation allows 2 viapoints only, AFAIK.

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>the limitation is, Navigation allows 2 viapoints only, AFAIK.

If you use BRouter explicitly (rather than implicitly) you can have up to 9 via points. I can find manual reference if you need more info.

Advantage is that via points can be inserted/ moved/ deleted if calculated track is not to your liking, although not as fast as "rubber-banding" like on some website editors. With internal Locus navigation, those 2 via points can't be moved once track is calculated - you get an error message like below ("point is not stored in database"):

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If Locus navigation allowed more via points, and those points could be later inserted/ moved/ deleted, and auto-recalculation occurred (topic & topic), then there would be no need for the explicit BRouter method of track calculation.

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that is true - I know about the multiple Brouter viapoint possibility, but was intentionally speaking in Locus only context. But, that cannot be easily used for the start-viapoions-end guidance

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Libor, Thank you for the comment. All my operations are closed in Locus on my Android phone, not using any other services like BRouter. I tried to create a route having 4 trackpoints as the attached screenshot, and enabled Guidance. (Since I amnot hiking right now, I chose a location and moved the center of map as a substitute of my current GPS position)

Locus points "280m" to the nearest point, which I didnot created. I checked this route by exporting as a file, it contained 4 lat/lon entries only. I also tried Navigation, but Locus still pointed the nearest point so no difference. Just to be clear, I want to have a guidance line as (B) while Guidance.

While this test, I noticed if I set the guide info on the upper area (indicated as (A)) to "Distance to next waypoint", at least I could know the distance to the next trackpoint.

Maybe this is a design concept of Locus, user should always get back to the route as much as possible, but in my use case I just want to know a straight-line distance to next target.

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When you say you have not created the trackpoint, who created it?

Or, is possible that all you want is not the nearest, but the next one?


Edit: When guidance is active, if you press the guidance button there are 2 items: Nearest point and Next point.Isn't it what you want? Also, check if your guidance settings are OK, and. you do not miss the trackpoint while passing across it.

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Libor,

>When you say you have not created the trackpoint, who created it?

I donot say I didnot create trackpoint. What I did was "Add new route & measure" and clicked 4 places on the map, and saved it as a route. Then set the route for Guidance. Locus pointed some point (that I didnot create) in the middle of the route, as showed the small arrows in baby-blue color in my screenshot.

I supposed those points (not trackpoints) are created by Locus automatically when I activate Guidance.

I aware "Nearest point" and "Next point" menu, but it doesnot point to trackpoint (unless I select "Next point" repeatedly until the arrow reaches the expected trackpoint).

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It looks like Locus uses some sort of Track guidance priority, in the opposite to trackpoint guidance priority, as analog of Route/Point priority recalculation in Navigation. What surprises me, as I have thought there is guidance directly to next trackpoint.

It is probably not a stored, but just a calculated point of the straight line between adjacent trackpoints. The angle of approaching to this point looks like a trade off between returning to track as soon as possible and the shortest path to the next trackpoint.

This approach may be actually wise, as Locus may suppose you has chosen the track for a reason. There may be good reason you SHOULD go from one trackpoint to the next one via straight line.This may mean - spending time out of a track/straight line can be anything from the annoyance up to the danger, what Locus cannot know..

Imagine the scenario you are in mountains on a challenging track. Next viapoint is 500 m away. You got from whatever reason 50 m aside of the planned track with much worse terrain. What would you prefer ?

A) Returning to the track after some 70-80 m, and then follow the track to the viapoint? or

B) Following the shortest path to the trackpoint via a line convergent with the track, passing 500 m of bad terrain for no good reason ?

Another scenario - nautical navigation to an atol lagoon between coral reefs, or to a port with a narrow passage. Deviation from a straight line may mean a shipwreck.

But I do not use Guidance mode much, so more experienced user can give better advices/explanations.

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Do you use Scrict route following ( Advanced section in Guidance options ) ?

If yes, does the pointing behavior differ if set to No ? As I can imagine if the Scrict following is used, and if was the author, I would additionally implement the behaviour you observed.

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Libor,

I think there is also the case the user intentionally doesnot follow the route. In mountain I know the peak(s) I will trace, but donot know the actual route. In that case I will make a route by connecting each peaks, and follow the actual trace from the trailhead. I can check I am heading to the right peak, but the current Locus implementation points some unknown point on the route I *willnot* go. That's the problem I am actually encountering. Yes I can know the distance to the next trackpoint, but I want the arrows at Guidance points the peak like a compass. (When you use compass, you will set some target (peak/col/junction) and will never change the target until you reach the target place)

The current Guidance works well when you perfectly know the route, including every corner and junction. Such a route is roads in the city so maybe Locus leans toward such a use case.


>Do you use Scrict route following ( Advanced section in Guidance options ) ?

No. When I enable that option, Locus follows the all points from trackpoint#1 even if trackpoint#2 is the nearest trackpoint. The arrow points the points, not trackpoint#2.

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For now, I do not see solution, but a workaround - switching between point by point guidance and track guidance. Guidance to point A. Than guidance to point B, avoiding guidance along a route.


I have raise an idea guidance-route/point-priority

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@Haruki Yamada. I've made some tests. See in the zip attachment because to long to publish here.

In the .zip see .txt and used test sample gpx file

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If you want Points indicated, even when track is +/- transparant, export as rte (route file) and reimport. Locus will show rte tagged points on the map with a red down arrow.

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0709,

Thank you for your detailed instruction and help! Finally I was able to setup Locus for my use case (pointing trackpoints only at Guidance). I figured out the required option was "Notify on every trackpoint" in Guidance option (I admit I have never tried this option, since I donot use notification feature...). With this option, Locus behaved perfectly as I wanted. Thank you for the info about changing the guidance line style, too, I will try.


Libor,

Thank you for your help, too. The discussion will help for understanding the use case I described.


Now this question can be set to "SOLVED". Thank you!!!

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Or, if you want the pure Guidance Start-viapoint1-viapoint2-destination, why do you generate the other points ? Just to have 4 points, being guided from one to another....

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the limitation is, Navigation allows 2 viapoints only ?

Using the "route and measure function" you can add multiple (*must pass) viapoints.

@ Haruki: Your specific question. I think not possible actually. Some guiding experts here ?

In exported and reimported file (gpx1.1) you do see the down arrows (via points) on your track.

Select individual via point one by one during walk and select guide to single (via)point ?

I am not 100% sure as I am only using the Navigation feature.

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For guidance or route creation - yes. But for navigation via Locus navigation dialog - not.

But one can IMHO define viapoint based track and make Locus to use navigation, eventual with Point priority recalculation - supposing there are OSM ways.

I admin I do not use some Locus ways of operation much.

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Hi Haruki,


you've gone through a very complex discussion as I can see. Thank all of you guys!

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Glad, the old guiding system helps Haruki.

The only small (so not urgent) issue I noticed.

- Locus strict guiding:

Points are strict, only around start and finish point I noticed some "wild" indicator jumps between points.

Looks and (notification) sounds see video: https://www.youtube.com/enhance?v=nhYbkv5vyRw

Here shown at start, but with some 'fiddling around' by virtual gps center moves also can be generated near end of track.

In example start and stop are very close for demo ! Anyway may happen in real also.

Regards, Willy.

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