Lorouter fails where Brouter works (conlusions: not that & other stuff)

[francisco]

Last weekend I'd been in a navigation workshop with a difficult track to test. The 22 Km. track was for 4x4 offroad, in dirty roads that were present in Locus Maps.
I did it with 2 devices, one with Locus 4 Gold and offline-Lorouter (updated 1 hour before the run) and another device as backup with Locus Pro and offline-Brouter. Same maps & configurations on both devices, except the offline router.
The GPS precision was very good, always between 3 and 6 meters.

1- Locus 4 Gold with offline-Lorouter
Several times the turn-by-turn presented a big "?" and I could became lost in the middle of nowhere.

2- Locus Pro with offline-Brouter
Always indicated me the way to go; so the backup-device turned the main device

So my first conclusion is  that offline-Lorouter is far away (yet ?) of the power of offline-Brouter.
And that offline-Lorouter is not for offroad, or offline-Lorouter is still in a beta stage and still dangerous for real adventures (without other device as backup), and if so should be noted by Locus.

Or something else I hope someone with more experience can share 

[Menion]

Hi francisco,

Big "?" in navigation usually means that you are out of computed route and you should on the map see, where is the recommended path. To me, it mainly looks that LoRouter and BRouter computed different routes. Is it correct?

Both routers use their own set of routing profiles. You probably do not share exactly the same profiles in both routers right?

So, to at least compare both routers, the best should be if you share with us here the start and end coordinates and type of routing you choosed for BRouter and LoRouter.

[francisco]

Hi francisco,

Big "?" in navigation usually means that you are out of computed route and you should on the map see, where is the recommended path. To me, it mainly looks that LoRouter and BRouter computed different routes. Is it correct?

Both routers use their own set of routing profiles. You probably do not share exactly the same profiles in both routers right?

So, to at least compare both routers, the best should be if you share with us here the start and end coordinates and type of routing you choosed for BRouter and LoRouter.

Hi Menion,
Yes, probably Lorouter and Brouter calculated different routes; Lorouter was on hiking and Brouter on MTB (both good for 4x4 offroad). But I wasn't in "route" mode, but following a track and automatic recalculation inhibited in both Locus, as always I do when navigating tracks .
I can't reproduce the other configurations, because I changed them after the track.
But I note that I was navigating a pre-made track, not a route/waypoint navigation, and had navigation indications in both Locus ; till certain moments in Locus 4, when those indication disappeared with that "?" - and I was in the track, not out of the track and I was seeing it in both screens. The secondary problem was that when in "?" "mode" is impossible to navigate to anywhere.
For example: when the last "?" happened in Locus 4 I decided to go to a nearest waypoint on an asphalt road; Locus 4 did not give answers because was in "? mode". But for example Waze putted me where I want with a route half in dirty-roads and another half in asphalt roads. And Locus pro + Brouter also.
An important note: Locus 4 was in Garmin Overlander (so no heat or gps antenna problems) and Locus Pro - as backup -and Waze, were in a mobile phone, so navigation conditions against it.
Now the very heat season started in my country and is forbidden to do offroad in my area; so I'll make new tests maybe by September / October and post results.
A suggestion: a friendly option to download Lorouter routing data is necessary; is a remote possibility - but a possibility - that I downloaded the wrong data, but there is no way to know if the data we've downloaded  is relevant to the tracks we pretend to do.
Or a "guide" with images. Brouter has that option, and that is why I'm going to use it.

[Menion]

Hello francisco

thanks for the very detailed description. I'm anyway not sure, how may I help here. You wrote you use completely different routing profiles, so how you want to compare the navigation capabilities of both apps? Integrated LoRouter, external BRouter from Google Play, or online LoRouter ... all should return identical results when you use exactly the same routing profiles. Data used for routing are also probably identical. So give a try to the same profile. You may use custom routing profiles in offline LoRouter or BRouter so use the same!

Btw. the easiest method to verify you have required routing data for offline LoRouter is to open detail of any LoMap in the Locus Store. There is in the middle option to download routing data.

Sorry I do not have more usable answer.

[francisco]

Hello francisco

thanks for the very detailed description
...
Sorry I do not have more usable answer.

Report on the error - is not an error
Due to Menion observations I made new tests.
This is relevant to conclusions: I used an Android phone arm64 with a CPU with 8 cores 1708-2073 MHz & GPU Adreno TM 619, 6 Gb Ram, 256 Gb Internal memory and Locus & Brouter in Internal memory. Always very good GPS signal (< 3 to 6m)
Today I tested only in Locus 4 Gold this combination of situations, in streets of my city (Lisbon-Portugal). These streets are very known and principal ones and present in all maps.
x - navigate a pre-made track
y - navigate to a waypoint
   X
a - using Lorouter offline
b - using Brouter offline
   X
k - using Lomaps
m - using OpenAndroMaps

Conclusions:
1 - big "?"

1.1. happens both in Brouter and Lorouter when we are out of the track or route, or Locus "thinks" we are (weak GPS signal ?); so not an error or malfunction.

1.2. Recalculations in the upper scenarios delay very much time (30" to 1 minute, or more); But Brouter is quicker then Lorouter by ~15 to 20". Is too much time for recalculation, considering that when we are in a road or a city street we can't stop, so recalculations never ends if there are various possible way outs during the driving & recalculations; also when we are in dirty-roads with several way-outs while recalculations are being done, recalc also never ends.

1.3. Apparently when a big "?" appears the most advisable is to stop and wait till the recalculation ends; but this is not possible most of the times; and also when we stop recurrently the map is not aligned with the direction we are going to so we went on a loop of recalculations when we begin drive going for a wrong way due to map alignment.

2 - name of streets
Although voice commands says the name of the streets, the navigation panel says "unknown street"; not relevant to me because I use Locus for offroad navigation and Waze or Sygic for road navigation.

3- Zoom levels
Although I've defined specific zoom levels in Automatic zooming (for 4x4 offroad or slow speeds the default ones are not appropriate) each time I start a navigation those zoom levels are overriden; during navigation I've to redefine it. But when navigation stops those zoom levels return to the ones I defined in 1st. instance and are this ones I pretend to use always till I redefine it only if I need ; I don't find the reason for this.

4 - Main conclusion (& suggestions):

4.1. improve speed of recalculation algorithms & also highest priority in the execution of those algorithms

4.2. solution for zoom levels not override (a guide or algorithm error?)

[Menion]

Hello,

4.1 Recalculation speed
- here it highly depends on the distance the BRouter has to compute. The longer the distance, the speed grows almost exponentially. For common hike & bike, it is not a big problem I believe. Most of the routes is below 50km and for this, speed is good enough. For longer routes it may be a problem, agree.

Bigger problem is, that even Radim, who in our team work on routing profiles, isn't experienced enough, to bring some noticable speed improvement to the BRouter system, so it is more on the work of Arndt (developer of the BRouter).

4.2 Auto-zoom
This will be a lot easier . You probably has set to apply certain "Preset" when navigation starts (in the navigation settings). So modify this preset!

[francisco]

Hello,

4.1 Recalculation speed
- here it highly depends on the distance the BRouter has to compute. The longer the distance, the speed grows almost exponentially. For common hike & bike, it is not a big problem I believe. Most of the routes is below 50km and for this, speed is good enough. For longer routes it may be a problem, agree.

Bigger problem is, that even Radim, who in our team work on routing profiles, isn't experienced enough, to bring some noticable speed improvement to the BRouter system, so it is more on the work of Arndt (developer of the BRouter).

4.2 Auto-zoom
This will be a lot easier . You probably has set to apply certain "Preset" when navigation starts (in the navigation settings). So modify this preset!

For 4.1 - the tests were: 1st. for 3,5 Km. track; 2nd. route to waypoint at 1,5 Km ; so no big calculations due to the track or route extension;
For 4.2. I'm going to explore that; I think that an updated Manual is essential because there are so many little things that our head went in " error FFF - out of memory"

[francisco]

Now about the phenomenon that the route calculation never ends
Take a look at the drawing (attachment of this post) and suppose you are on a circular road, from which several streets exit and all of them lead to our destination, the swimming pool in the center. If we are driving the car it will choose the nearest street to turn left; but as we are walking we have already passed that street and it will calculate for the 2nd street after, but as we are walking we have already passed the 2nd street ... etc; in this example the recalculation is infinite and we never know which way to go, except if we stop or slow down to give the calculation time to finish

[francisco]

One additional note about calculation: I made a test with a route (waypoint navigation) in Locos (both offline Brouter and Lorouter), and in Sygic (offline maps).
In Sygic the speed of calculalation, for example when we miss a street, is very fast compared with Lorouter and Brouter.
I know are different apps. But a note to optimize Lorouter calc speed /priority on execution.