Author Topic: Weeding/editing routepoints for navigation of a route...  (Read 5479 times)

Weeding/editing routepoints for navigation of a route...
« on: 25 April, 2014, 10:00:37 am »
I've been doing some test navigations of a shortish route with, probably too many routepoints and a handful of user waypoints (on Vista HCx)...  and also note in ff's article... http://www.aukadia.net/gps/lwg_1.htm
Quote
In follow road mode all Garmins can only handle 50 points in a route. But this is loads - most people probably only use about 10. And it does work best if these Routepoints are also proper User Waypoints.

So the questions are (feel free to point out an explanation somewhere I've missed), what's the best way having made a route, to edit down the number of routepoints, to avoid endless notifications of e.g. "via point 23: Pt23".  How do people approach annotation of a route with informative user waypoints (route points with added info?), and do people generally delete routepoints that are simply half-way along a straight road..?

Cheers
Andy

Cycle and recycle.   SS Wilson

frankly frankie

  • I kid you not
    • Fuchsiaphile
Re: Weeding/editing routepoints for navigation of a route...
« Reply #1 on: 25 April, 2014, 11:38:16 am »
What software or planner are you using to construct your short Route?  It rather sounds as though it's generating far too many points.  And what map in the GPS?  A Route of say 20km/12miles shouldn't require more than about 6 points, since you appear to be working in 'follow road' mode.

The main problem is ensuring the GPS in 'follow road' makes the choices you expect it to make, ie goes along the same roads that you planned.  The simplest way to do this is to err on the 'more points' side, rather than 'fewer'.   Unless, of course, you actually want your GPS to take you on a magical mystery tour.
In typical laney UK topography, it might be reasonable to aim for an average of say 1 Route point per 5km - so that the 50-point limit would allow you around 250km, or a very long day ride with a single Route. (Though with storage for 50 Routes there's nothing wrong with using 2 or 3 in a day.)  But does 1 point per 5km really guarantee that you'll follow the planned itinerary?  I'm not sure it does, in laney country.  (It would in mid-Wales, or in most of France - but possibly not in Hampshire say.) 
But certainly, I'd say, if you have points more frequently than say 1 per 3km on average, then there's something wrong - and that's when you get the 'nagging' effect on the GPS. 

Others who use this mode more than I do (I prefer 'direct' mode), may be able to fine-tune these figures a bit.

You could approach it another way and assume that 1 follow road point should be able to replace 3 route instructions, ie 3 turns where you would need a point in 'direct' mode.  I think that will give a similar frequency of 1 point per 3-5km, on UK lanes.

Another worthwhile tip for 'follow road' mode is to put your points on the roads you want to use, and not on the junctions.  Leave all the decision places clear of clutter, so that the GPS can do its thing.  Otherwise, the points you add will interfere with the instructions the GPS is trying to give.  Try it both ways and you'll see what I mean.
This is the opposite of 'direct' mode where you would want to put your points on the junctions (or a bit before, or a bit after, depending on which of the three sects of the direct religion you belong to).
This is why, when planning a Route, it's best to have a clear plan of which mode you are going to use on the GPS.

There's no need to differentiate between User Waypoints and Route- (Via-) points, since your GPS can store 1000 User Waypoints which is loads - enough for 20 50-point Routes or about 5000km ...
when you're dead you're done, so let the good times roll

PaulF

  • "World's Scariest Barman"
  • It's only impossible if you stop to think about it
Re: Weeding/editing routepoints for navigation of a route...
« Reply #2 on: 25 April, 2014, 11:54:07 am »
Still trying to find your way to the shops? :)

I fell foul of the 50 points in route on the Harlequin Hack, but my eTrex was working fine in 'off road' mode so I might say that it doesn't matter.

What I try to do it to put my waypoints after the junction so that as you approach the arrow points in the direction that you need to turn, only if the road curves significantly do I put an intermediate point - I think this is the same approach as Frankies'.

frankly frankie

  • I kid you not
    • Fuchsiaphile
Re: Weeding/editing routepoints for navigation of a route...
« Reply #3 on: 25 April, 2014, 12:12:18 pm »
No I'm a 'plumb on the junction' man but I do try very hard to eliminate points between junctions.  Only if the road shape immediately after an instruction bends right round would I add a 2nd point to maintain shape near the instruction.  That's in direct mode though.  Some of my Route files in central France have over 20km between points and it's great to do a left turn and then see essentially "nothing to think about for an hour"  :thumbsup:
when you're dead you're done, so let the good times roll

Re: Weeding/editing routepoints for navigation of a route...
« Reply #4 on: 25 April, 2014, 12:22:14 pm »
I'm also firmly in the camp of a routepoint on each relevant** junction - and direct (off-road) navigation mode, that way I'm not troubled by the 50 point limit, nor any surprises in routing sending me all around the country.

However since most routes return to point of origin there is a lot to be said for separate out & back route files - which often come within the 50 point limit anyway.

** relevant in this contect meaning that a white line is crossed and on an audax there would normally be a routesheet instruction.

Re: Weeding/editing routepoints for navigation of a route...
« Reply #5 on: 25 April, 2014, 01:30:54 pm »
What software or planner are you using to construct your short Route?  It rather sounds as though it's generating far too many points.  And what map in the GPS?  A Route of say 20km/12miles shouldn't require more than about 6 points, since you appear to be working in 'follow road' mode.

The main problem is ensuring the GPS in 'follow road' makes the choices you expect it to make, ie goes along the same roads that you planned.  The simplest way to do this is to err on the 'more points' side, rather than 'fewer'.   Unless, of course, you actually want your GPS to take you on a magical mystery tour.
In typical laney UK topography, it might be reasonable to aim for an average of say 1 Route point per 5km - so that the 50-point limit would allow you around 250km, or a very long day ride with a single Route. (Though with storage for 50 Routes there's nothing wrong with using 2 or 3 in a day.)  But does 1 point per 5km really guarantee that you'll follow the planned itinerary?  I'm not sure it does, in laney country.  (It would in mid-Wales, or in most of France - but possibly not in Hampshire say.) 
But certainly, I'd say, if you have points more frequently than say 1 per 3km on average, then there's something wrong - and that's when you get the 'nagging' effect on the GPS. 

Others who use this mode more than I do (I prefer 'direct' mode), may be able to fine-tune these figures a bit.

You could approach it another way and assume that 1 follow road point should be able to replace 3 route instructions, ie 3 turns where you would need a point in 'direct' mode.  I think that will give a similar frequency of 1 point per 3-5km, on UK lanes.

Another worthwhile tip for 'follow road' mode is to put your points on the roads you want to use, and not on the junctions.  Leave all the decision places clear of clutter, so that the GPS can do its thing.  Otherwise, the points you add will interfere with the instructions the GPS is trying to give.  Try it both ways and you'll see what I mean.
This is the opposite of 'direct' mode where you would want to put your points on the junctions (or a bit before, or a bit after, depending on which of the three sects of the direct religion you belong to).
This is why, when planning a Route, it's best to have a clear plan of which mode you are going to use on the GPS.

There's no need to differentiate between User Waypoints and Route- (Via-) points, since your GPS can store 1000 User Waypoints which is loads - enough for 20 50-point Routes or about 5000km ...

Thanks ff.  I think I've used an artificially small Route (commute) of ~15km.  IIRC I 'constructed' the route in rwgps, then uploaded to bikehike, and 'pruned' it to 50 routepoints and then saved it as a Route, and opened it in Mapsource running OFM_UK (2012).  So quite convoluted.  Perhaps I should have tried reducing to ~15 routepoints.  is there a program that will follow one's chosen philosophy of routepoints between/at/after junctions?   I haven't worked out how to import a Track to mapsource and then save as a Route. Last night I switched to talkytoaster's routable British Isles +10M contours, for the Vista HCx and Basc/Mapsource.  Is OFM_UK 2012 still fine, they were directing to talkytoaster.

I should know, but what is the main difference between routing with 'Follow Road' & 'Off road'?  I was also experimenting also with proximity beeps, and found the option to turn off the 'leaving area' beep, what effect the size of proximity has, and also managed to set the 'marine' off course alert to 200m.  I found beep on turn a tad annoying but this was because there were too many routepoints.
Cycle and recycle.   SS Wilson

Re: Weeding/editing routepoints for navigation of a route...
« Reply #6 on: 25 April, 2014, 01:36:57 pm »
Still trying to find your way to the shops? :)

I fell foul of the 50 points in route on the Harlequin Hack, but my eTrex was working fine in 'off road' mode so I might say that it doesn't matter.

What I try to do it to put my waypoints after the junction so that as you approach the arrow points in the direction that you need to turn, only if the road curves significantly do I put an intermediate point - I think this is the same approach as Frankies'.

 :)  My first real test of etrex routing may be the Blowingstone Audax on 18 May, hopefully I won't be beeping more than needed.   The Harlequin Hack was the first time Android MyTracks has died on me, perhaps it was osmand crashing that took it out too.  I've also since discovered that, for me, map set to up for 'direction of travel' is easier than 'North is up', so have set the etrex to 'track is up' on the map now.
Cycle and recycle.   SS Wilson

frankly frankie

  • I kid you not
    • Fuchsiaphile
Re: Weeding/editing routepoints for navigation of a route...
« Reply #7 on: 25 April, 2014, 07:03:02 pm »
IIRC I 'constructed' the route in rwgps, then uploaded to bikehike, and 'pruned' it to 50 routepoints and then saved it as a Route, and opened it in Mapsource running OFM_UK (2012). 

Maybe over-thinking it.  Why not set up your Route direct in Mapsource?  Granted it's a dog to use - but then so are nearly all the online planners IMO.  Set the routing to 'auto' in Preferences (and set any other routing preferences such as 'avoid unpaved'.  Provided it's a routable map of course, you can then get a feel for how far apart you can put points and still have it routing the way you want.
The routing is NOT transferred to the GPS but you have to assume the two Garmin products will take a similar view.
In practice the routing on the GPS never works quite the same way (even though they are both Garmin products of a similar generation) so it's wise to increase the points density slightly 'just in case' - but only slightly.

Quote
So quite convoluted.  Perhaps I should have tried reducing to ~15 routepoints.  is there a program that will follow one's chosen philosophy of routepoints between/at/after junctions?   I haven't worked out how to import a Track to mapsource and then save as a Route.

1) For a 15km Route, I really think 15 points is too many.  My 20km route to work had ... er ... 7 'turns' and it wouldn't take more than 4 points to define that in follow road, including start and finish. 
You have to allow the GPS routing algorithm to do some stuff, because otherwise if you try to pin it down completely you just get (as you've found) spurious prompts - but they are worse than spurious, they are blocking the useful prompts that you would otherwise be getting if you were giving it a bit more breathing space.   So I'd suggest the ratio of points to 'turns' should always be less than 50%.  Otherwise you really would get better results with direct routing and one point per turn.

2) Expecting a GPS or any other software to be able to second-guess what a cyclist might choose, is I think asking rather a lot.  Maybe some future generation of GPSs with multi-core processors might be able to make a stab.  But there are so many variables even down to tiredness at the end of a day, or wind direction.

3) I strongly recommend anyone who uses Mapsource to download the freebie utility WinGDB3   http://www.sackman.info/
This is optimised to work with GDB files and has loads of Route/Track conversion options.  Really it's stuff that a better and more mature Mapsource would have right there on the menu bar, but doesn't.

Quote
I should know, but what is the main difference between routing with 'Follow Road' & 'Off road'?  I was also experimenting also with proximity beeps,

Well, everything.  Follow road is actual autorouting.  Off road aka 'direct' is not - the GPS just acts dumb.  With the first, you are expecting the GPS to do stuff for you, and very often it's wonderful but sometimes it just isn't.  With the second, you program the GPS with what you want to do - and it just relays your own programming back to you at the right place.

I find autorouting works well with a short 'find and go to' within limits of say 10-20km.  Otherwise - I go direct.
when you're dead you're done, so let the good times roll

Re: Weeding/editing routepoints for navigation of a route...
« Reply #8 on: 26 April, 2014, 10:34:33 am »
Thanks ff.   :)   

I've redrawn one of my routes as a Route in Mapsource, but I can't see a way of showing where the all waypoints are positioned, or how many there are on the route; in order to try and edit.   How do you show all via/way points as blue flags?

edit.  Had a little play with wingdb3, and managed to convert Route viapoints to blue flag waypoints (using code 141 in prefs).   




Cycle and recycle.   SS Wilson

Re: Weeding/editing routepoints for navigation of a route...
« Reply #9 on: 27 April, 2014, 03:51:25 pm »
If I want to make a Route to navigate 'off road' , and having received a gpx track from the ride organiser, what the best approach for a 'direct' off road navigation Route?

e.g. if one wants to construct a Route, with the route sheet instructions as waypoints...

Is it best to use the gpx track displayed in mapsource, and start by adding waypoints at all the junctions onto the track, annotating according to route sheet e.g 1-R, 2-SO, 3-LR etc.
Then, using the route tool, construct a route clicking in the minimum number of Routepoints (at junction or after), while following the track & waypoints on the map, and then download Route & waypoints...

Can I just clarify, proximity beep use.  If one sets a proximity distance on user waypoints to beep, will the unit still beep even if one turns off 'turn warning' in 'Tones' ?  What's best?
Cycle and recycle.   SS Wilson

PaulF

  • "World's Scariest Barman"
  • It's only impossible if you stop to think about it
Re: Weeding/editing routepoints for navigation of a route...
« Reply #10 on: 27 April, 2014, 03:56:38 pm »
Don't know how mapsource works but in Basecamp, it's easier to create a route: there's a route, tool that allows you to click on points on the map and it links them as a route. No need to create the waypoints first.  I think in gps terms there's a difference between routepoints and waypoints?

Feanor

  • It's mostly downhill from here.
Re: Weeding/editing routepoints for navigation of a route...
« Reply #11 on: 27 April, 2014, 04:01:47 pm »
It's the same in Mapsource.

I'd not advise putting a User Waypoint at every routesheet instruction.
That would be just too many, IMO.

I'd bring the track into mapsource, place waypoints at the controls, and then use the route tool to build a route between the control waypoints.
Drag the route to create intermediate 'via' points until the route is constrained to follow the track.

But everyone has their own way of working, and there's no right or wrong.   Just what works for you.

frankly frankie

  • I kid you not
    • Fuchsiaphile
Re: Weeding/editing routepoints for navigation of a route...
« Reply #12 on: 27 April, 2014, 04:16:22 pm »
I think a proximity waypoint will always beep (assuming you have proximity beeps turned on as a general setting in the GPS) - regardless of whatever mode you're in.  In other words, whenever the GPS gets within xxx distance of a proximity waypoint, it will beep.   If you can, it's quite a good idea to disable the 'leaving' beep - generally you only need to know that you are arriving, not leaving.  They're very good for info controls, and some people like them for all control points.

Is it best to use the gpx track displayed in mapsource, and start by adding waypoints at all the junctions onto the track, annotating according to route sheet e.g 1-R, 2-SO, 3-LR etc.

My workflow is exactly that, so far, though I do try to use the minimum number of 'instruction' points possible.  Certainly not every mapped junction - just every routesheet instruction.  I name the Waypoints in the way you suggest (using 2 chars for the unique Id bit) - I don't bother with the Comment field (because the Vista doesn't display it, in any navigational mode).   I also, in Mapsource, have the default symbol for Waypoints set up as 'City Medium' which is a small grey blob.  This removes blue flag clutter from the GPS screen.

Then I construct the Route (with autorouting turned off in Preferences) by clicking on each Waypoint in turn.  (What this actually does is create Routepoints that inherit the properties of the existing Waypoints.)  NB if you don't utilise the Waypoints in this way, they won't really be much use just as standalone objects - not in a Vista anyway.

Then, if any shaping is required (and it has to be a fairly extreme case before I'll add any intermediate shaping points) I insert a point by right-clicking on the route and 'Insert Route Section'.  NB this inserts a Routepoint (aka Viapoint) NOT a Waypoint - it is not editable for name but that doesn't matter much because it's not marking a turn anyway.

On an event, I'd either do 1 Route per leg or (for a shorter event) 1 Route out and 2nd Route back.  On tour riding place to place, just 1 Route per day.
I use the GPS with 2 data fields showing - 'Waypoint at next' (which displays the name, ie the next instruction) and 'Distance to next'.


Waypoint naming for direct routes     Why I avoid 'shaping' points
when you're dead you're done, so let the good times roll

Re: Weeding/editing routepoints for navigation of a route...
« Reply #13 on: 27 April, 2014, 06:23:21 pm »
It's the same in Mapsource.

I'd not advise putting a User Waypoint at every routesheet instruction.
That would be just too many, IMO.

I'd bring the track into mapsource, place waypoints at the controls, and then use the route tool to build a route between the control waypoints.
Drag the route to create intermediate 'via' points until the route is constrained to follow the track.

But everyone has their own way of working, and there's no right or wrong.   Just what works for you.

Ditto.

Two Waypoints per route. Up to 10,000 Viapoints IIRC.

Re: Weeding/editing routepoints for navigation of a route...
« Reply #14 on: 27 April, 2014, 10:49:27 pm »
It's the same in Mapsource.

I'd not advise putting a User Waypoint at every routesheet instruction.
That would be just too many, IMO.

I'd bring the track into mapsource, place waypoints at the controls, and then use the route tool to build a route between the control waypoints.
Drag the route to create intermediate 'via' points until the route is constrained to follow the track.

But everyone has their own way of working, and there's no right or wrong.   Just what works for you.

Ditto.

Two Waypoints per route. Up to 10,000 Viapoints IIRC.

And if you have four info controls?    :)
Cycle and recycle.   SS Wilson

Re: Weeding/editing routepoints for navigation of a route...
« Reply #15 on: 27 April, 2014, 10:52:51 pm »
I think a proximity waypoint will always beep (assuming you have proximity beeps turned on as a general setting in the GPS) - regardless of whatever mode you're in.  In other words, whenever the GPS gets within xxx distance of a proximity waypoint, it will beep.   If you can, it's quite a good idea to disable the 'leaving' beep - generally you only need to know that you are arriving, not leaving.  They're very good for info controls, and some people like them for all control points.

Is it best to use the gpx track displayed in mapsource, and start by adding waypoints at all the junctions onto the track, annotating according to route sheet e.g 1-R, 2-SO, 3-LR etc.

My workflow is exactly that, so far, though I do try to use the minimum number of 'instruction' points possible.  Certainly not every mapped junction - just every routesheet instruction.  I name the Waypoints in the way you suggest (using 2 chars for the unique Id bit) - I don't bother with the Comment field (because the Vista doesn't display it, in any navigational mode).   I also, in Mapsource, have the default symbol for Waypoints set up as 'City Medium' which is a small grey blob.  This removes blue flag clutter from the GPS screen.

Then I construct the Route (with autorouting turned off in Preferences) by clicking on each Waypoint in turn.  (What this actually does is create Routepoints that inherit the properties of the existing Waypoints.)  NB if you don't utilise the Waypoints in this way, they won't really be much use just as standalone objects - not in a Vista anyway.

Then, if any shaping is required (and it has to be a fairly extreme case before I'll add any intermediate shaping points) I insert a point by right-clicking on the route and 'Insert Route Section'.  NB this inserts a Routepoint (aka Viapoint) NOT a Waypoint - it is not editable for name but that doesn't matter much because it's not marking a turn anyway.

On an event, I'd either do 1 Route per leg or (for a shorter event) 1 Route out and 2nd Route back.  On tour riding place to place, just 1 Route per day.
I use the GPS with 2 data fields showing - 'Waypoint at next' (which displays the name, ie the next instruction) and 'Distance to next'.
...

Thanks ff.  I decided to give this a go.  Mapsource is kind of frustrating but I'm slowly getting used to it; should campare with basecamp.

edit.  done a smaller route, but waypointing a 200km onto a mapsource route would be a task and a half...   ;)
Cycle and recycle.   SS Wilson

Re: Weeding/editing routepoints for navigation of a route...
« Reply #16 on: 27 April, 2014, 10:54:47 pm »
It's the same in Mapsource.

I'd not advise putting a User Waypoint at every routesheet instruction.
That would be just too many, IMO.

I'd bring the track into mapsource, place waypoints at the controls, and then use the route tool to build a route between the control waypoints.
Drag the route to create intermediate 'via' points until the route is constrained to follow the track.

But everyone has their own way of working, and there's no right or wrong.   Just what works for you.

Thanks - will try this too.  So presumably you don't use direct routing.
Cycle and recycle.   SS Wilson

Re: Weeding/editing routepoints for navigation of a route...
« Reply #17 on: 28 April, 2014, 12:41:37 am »
Been playing with this exact problem all weekend.

The software package I tracked down which appears to do everything bar transfer the file to the GPS is http://www.routeconverter.de/webstart/en
It has a Google Mpas overlay including an OSM cycling option, so you can use map, satellite or open cycle map as your mapping option. Place each point as you want, then name it directly.
Finalising the route is simply a case of converting the waypoint list to a route.

You can move, prune or rename points at will.

Highly recommended.

Feanor

  • It's mostly downhill from here.
Re: Weeding/editing routepoints for navigation of a route...
« Reply #18 on: 28 April, 2014, 08:08:18 am »
It's the same in Mapsource.

I'd not advise putting a User Waypoint at every routesheet instruction.
That would be just too many, IMO.

I'd bring the track into mapsource, place waypoints at the controls, and then use the route tool to build a route between the control waypoints.
Drag the route to create intermediate 'via' points until the route is constrained to follow the track.

But everyone has their own way of working, and there's no right or wrong.   Just what works for you.

Thanks - will try this too.  So presumably you don't use direct routing.

No, I use follow-the-road routing.
Which is why I don't place waypoints at every routsheet instruction.
I simply constrain the on-the-road route with sufficient via points.

Re: Weeding/editing routepoints for navigation of a route...
« Reply #19 on: 28 April, 2014, 12:04:22 pm »
It's the same in Mapsource.

I'd not advise putting a User Waypoint at every routesheet instruction.
That would be just too many, IMO.

I'd bring the track into mapsource, place waypoints at the controls, and then use the route tool to build a route between the control waypoints.
Drag the route to create intermediate 'via' points until the route is constrained to follow the track.

But everyone has their own way of working, and there's no right or wrong.   Just what works for you.

Thanks - will try this too.  So presumably you don't use direct routing.

No, I use follow-the-road routing.
Which is why I don't place waypoints at every routsheet instruction.
I simply constrain the on-the-road route with sufficient via points.

Ditto.

And every route terminates at a Control OR Info. ( So you don't ride past an Info and miss it. )

Re: Weeding/editing routepoints for navigation of a route...
« Reply #20 on: 28 April, 2014, 01:07:15 pm »
It's the same in Mapsource.

I'd not advise putting a User Waypoint at every routesheet instruction.
That would be just too many, IMO.

I'd bring the track into mapsource, place waypoints at the controls, and then use the route tool to build a route between the control waypoints.
Drag the route to create intermediate 'via' points until the route is constrained to follow the track.

But everyone has their own way of working, and there's no right or wrong.   Just what works for you.

Thanks - will try this too.  So presumably you don't use direct routing.

No, I use follow-the-road routing.
Which is why I don't place waypoints at every routsheet instruction.
I simply constrain the on-the-road route with sufficient via points.

Cheers.  I should know this, but with the method you describe AFAIUI, using auto-routing, when one clicks on the map and mapsource builds the route up to where you've clicked, what governs how many viapoints it uses/lays down?  So, in other words how do you normally avoid too many viapoints in mapsource i.e. how do you weed them down to the minimum needed?
Cycle and recycle.   SS Wilson

Feanor

  • It's mostly downhill from here.
Re: Weeding/editing routepoints for navigation of a route...
« Reply #21 on: 28 April, 2014, 01:21:10 pm »
It's the same in Mapsource.

I'd not advise putting a User Waypoint at every routesheet instruction.
That would be just too many, IMO.

I'd bring the track into mapsource, place waypoints at the controls, and then use the route tool to build a route between the control waypoints.
Drag the route to create intermediate 'via' points until the route is constrained to follow the track.

But everyone has their own way of working, and there's no right or wrong.   Just what works for you.

Thanks - will try this too.  So presumably you don't use direct routing.

No, I use follow-the-road routing.
Which is why I don't place waypoints at every routsheet instruction.
I simply constrain the on-the-road route with sufficient via points.

Cheers.  I should know this, but with the method you describe AFAIUI, using auto-routing, when one clicks on the map and mapsource builds the route up to where you've clicked, what governs how many viapoints it uses/lays down?  So, in other words how do you normally avoid too many viapoints in mapsource i.e. how do you weed them down to the minimum needed?

Using the Route tool in Mapsource, I click once on the start Waypoint, and then once on the destination Waypoint.
The machine draws a fat purple line along the ( wrong ) roads.
The Route properties show it contains exactly 2 Waypoints.
I then drag-and-drop the Route to the roads I want ( ie to follow the Track ).
Each time I do this, it adds 1 via point to the Route.
If I'm careful about where I place the via points, then it generally doesn't take more than a few to poke the Route along the way I want to go.

So I never have to weed down the number of via-points.
I start from zero, and add them as required.





PaulF

  • "World's Scariest Barman"
  • It's only impossible if you stop to think about it
Re: Weeding/editing routepoints for navigation of a route...
« Reply #22 on: 28 April, 2014, 01:26:56 pm »
What happens with Basecamp at least is that the route is stored simply as the set of route/waypoints. When it's displayed the system calculates the route dynamically. When you export it to a Garmin or other device just the points that you have selected are sent, the device then recalculates the route. So in theory the same set of points could give different routes on different devices if their maps or routing algoritms are different

Feanor

  • It's mostly downhill from here.
Re: Weeding/editing routepoints for navigation of a route...
« Reply #23 on: 28 April, 2014, 01:33:36 pm »
Which is exactly why I advise planning Routes using Mapsource loaded with the same maps you have in the GPS unit.
The route weightings of the maps will be the same, and the routing logic is hopefully the same too.

Of course, this is also why some people choose to use off-road routing, or Tracks.
This breaks the dependency on the maps.

frankly frankie

  • I kid you not
    • Fuchsiaphile
Re: Weeding/editing routepoints for navigation of a route...
« Reply #24 on: 28 April, 2014, 02:48:33 pm »
Which is exactly why I advise planning Routes using Mapsource loaded with the same maps you have in the GPS unit.
The route weightings of the maps will be the same, and the routing logic is hopefully the same too.

It isn't though.  Don't ask me to cite, but it has been demonstrated more than once, in this forum and elsewhere.  But the solution is simple enough - just increase the Route point frequency by a small amount, still well within the bounds of sanity.  (My idea of 'beyond sanity' would be > 1 Route point per 2 route instructions.)

There is a good reason for matching the map you plan with to the one in the GPS - it ensures that the Route points you lay down, are located precisely on Map points in the GPS.  I have a theory that this reduces the processing somewhat.
If on the other hand you plan in Google Maps (different map data) - your Route points will not be located on Map points and, since the map is an important part of the routing mechanism, there will be a processing overhead to reconcile all these 'off road' points.  OK, it is only a theory, and it's only going to affect the time it takes the GPS to do the initial route calculation.

I call them Route points because that's how they are tagged in the GPX.
when you're dead you're done, so let the good times roll