LoMaps + MapsForge V4

[Menion]

Hi guys,
finally, after years, we are preparing LoMaps based on the latest MapsForge V4 library.

Useful info (numbered so it may be easier to ask for additional info if needed).

1. Required Beta version 4.14.2.3+: http://bit.ly/lmVersionsTest

2. App contains the latest public code for MapsForge lib. So not the latest official 0.18.0 version, but 0.18.0 + latest changes and fixes: https://github.com/mapsforge/mapsforge/blob/master/docs/Changelog.md#new-since-0180

3. LoMaps, for testing of the new theme (currently only Europe) are prepared here: http://bit.ly/3IFmOS4

4. Public repository with the latest "LoMaps offline theme" and also tagging file is here: https://github.com/asamm/lomaps-mapsforge . Seems that @voldapet has to add some "readme".

5. You may notice that themes contains also a separate "poi" theme. This is a special addition currently only for internal LoMaps that affect the display of offline LoPoints (the base map theme does not contain instructions for the LoPoints icons at all). If interested, I may add support for this for public themes as well.

6. The New MapsForge library contains many useful improvements and also some fixes that may be interesting for overcomplicated hacks that are done in OpenAndroMaps regards colors (more here: https://github.com/mapsforge/mapsforge/pull/1366 )

7. Here also comes the idea to unite tag-mapping-xml for main MapsForgeV4-based maps. This should make a life for all theme creators so much easier. What do you think, mainly @Tobias?

8. I would also like to notify all map creators who have themes created for current V3-based LoMaps (and others) about this, namely: @john_percy , @Magellan , @karlchick , @LocusUser#1 , @Tobias, and others ...

9. And the last. If you notice any issue in the rendering system for V4 maps, feel free to ask me as well. I may help here a little bit.

10. New maps are not compatible with current public maps, so auto-loading won't work between them.

Uff, hope this is all. Thanks for reading and testing if someone will want to try it 

[Andrew Heard]

Well done @menion. I did some mucking around with the Ireland map, checking LoPoints. Twice LM completely froze with apparent high CPU load although not detected by Android as a crash. Even screen capture would not work. I just had LoPoints "around" for some category. Nothing too taxing. After re-run, LM displayed start-up screen but not Loading... & got no further until full restart. I wasn't sure what.ZIP theme file to use from Github so was just internal LM theme.

[Menion]

Froze? Hmm quite unexpected. Anyway maybe I see something in automatic crash reports, thanks, will look at it.

Themes > use internal. I've mentioned our repository just for theme creators or those who are interested in what is on the background.

[Andrew Heard]

Worse since - going all very slow. Even after phone reboot. Using New Zealand map. Gave up - LM essential for holiday; silly of me to test while away. Reverted to public 4.14 as previous .1 beta APK no longer available. Backup/ restore perfect, I think. Now no problem.
There was no crash so don't expect a report.

[michaelbechtold]

I'm not suffering like Andrew did, vector and raster maps fast and smooth. However, all vector maps show up in maps manager and in nearby list THREE times. I've imported one V4 LoMap and only then noticed. So I cannot tell if that issue was present before tth import already.
Regardless of the beta pain to come still, I'm happy about your contributions to MF and the move of LoMpas to V4. I.e. pain well spent :-)
Cheers
Michael

[balloni55]

my first impressions
- opening the theme window takes ~25 sec regardless which V4 card or theme is used
- neither in the map name nor in the map details the "normal user" can see that it is a V4 map

EDIT
in addition, the existing V3 map is overwritten without request and since I use LMP in parallel, this map is no longer available there

[Andrew Heard]

I'm not suffering like Andrew did, vector and raster maps fast and smooth

maybe some southern hemisphere issue? I could do more rigorous testing if home, but not while on holiday.

[T-mo]

- chosed 1 of the linked LoMaps and copied .osm.map to a dedicated folder inside mapsVector, skipped the poi.db
- offline-theme #4: put theme.xml and the 3 icon-folders to a separate directory and zipped it (compression none, store). Put this zip into mapsVector/_themes/

everything buttersmooth using new LoMap with this MF-theme and also with any other installed theme, no delays, theme-layers and switches all like expected

[Menion]

Hi guys,
thanks for useful info.

Version with fixed slowdown (hopefully is in preparation). The issue was in the MapsForge itself and in the way, how we use repeated symbols along the line.

New maps for Europe are already uploaded on Google Drive. The New Beta app version will be published tomorrow (or today evening).

@Tobias maybe this may be interesting for you. If you also find a while to verify that the rotation of symbols works correctly, it will be fine, thanks.

[Andrew Heard]

this may be interesting for you

wow - huge effort - impressive results

[balloni55]

my first impressions
- opening the theme window takes ~25 sec regardless which V4 card or theme is used
- neither in the map name nor in the map details the "normal user" can see that it is a V4 map

EDIT
in addition, the existing V3 map is overwritten without request and since I use LMP in parallel, this map is no longer available there

no answer and no improvement with V4.14.2.4 and new map 20.02.2023

[Tapio]

I have general questions:

a) Any difference to the available OAM Mapsforge V5 maps?
b) When will they be in the store?
c) Are they still exclusively used for e. g. retrieving the city name (for track naming)?

I noticed having more *.db of the same area (one is from asamm, the other from OAM) is not ideal. When I display Lopints Offline via the "Map-screen content" it displays many points twice because of the two databases.

[karlchick]

Some initial thoughts from me:

Point 1:

I see bicycle=designated is added.

Could we include the following?
   - bicycle=no|yes|designated|permissive
   - foot=no|yes|designated|permissive
   - horse=no|yes|designated|permissive


Point 2:

In the UK we have footpaths and bridleways that are legally protected and signed along their routes - these are known as Public Rights of Way (PROW).

OSM has inluded tagging for these ways (designation):

   https://wiki.openstreetmap.org/wiki/Key:designation

and has the following guidance for usage:

   https://wiki.openstreetmap.org/wiki/Access_provisions_in_the_United_Kingdom

Would it be possible to include this designation tag in LoMap maps?

For the UK, the following values would be useful: public_footpath, public_bridleway, restricted_byway, byway_open_to_all_traffic.
The following values are also used in Isle of Man: access_land, public_cycleway, green_lane.
The following values are also used in Scotland: core_path.

This would provide a massive improvement to be able to indicate footpaths that are of interest to hikers, cyclists and horse riders:
   - bridleways can often be part of a highway=track + designation=public_bridleway - these are currently not displayed in LocusMap but are quite common.
   - bridleways (in the UK at least) are also legally accessible for cyclists - some are sealed and useful to road-bikes but some not and need off-road bicycles.
   - many footpaths in OSM are foot=designated but only because there is a general (Cycle|Foot) signage used by the councils to indicate a shared space footway - these are publicly accessible paths, usually pavements, cyceways, side_walks, combined cycle lanes and footpaths - most are in/around towns. They are not PROW but if rendered as "footpaths" clutter the map with many "additional" paths, resulting in a "can't see the wood for the trees" situation for the walker...


Point 3:

Car parking amenities seem to be growing in OSM over the last year, to the point that the maps are starting to be cluttered with many additional parking=side_street.

Could you include the parking=* tag to help identify which car parking amenties are dedicated off-street parking from the many on-street packing, see:

https://wiki.openstreetmap.org/wiki/Key:parking

This tag is also useful for being able to indicate multi-storey and underground car parks.

When combined with access tag, it allows to identify those car parks that are publicly accessible and likely destinations for people arriving somewhere to park.


Point 4:

I see that many of the appear-zoom levels have been tweaked, some appearing much later...

I noticed when we went from v3 to v4 for OAM that there is a difference in visual scaling between LoMap and v4 maps of the same zoom level.
e.g. zoom=16 in LoMap appears similar in scale to zoom=15 in v4 maps.
This has the effect (for the user) that symbols/ways seem appear much later in v4 maps. When you zoom out in v4 maps you seem to get less information compared to when you switch to LoMap.
...so I was a little surprised to see some appear-zoom levels being increased for some tags...


Point 5:

The OAM maps have recently added OS crag data available from  OS open data. I think Christian did some magic scripting behind the scenes to make this possible for OAM and it is a massive improvement for UK maps.
Is this something that might be considered for LoMap v4?


Point 6:
In OAM maps the map tagging separates out common tag values, e.g. foot=yes and bicycle=yes are transformed into foot=ft_yes and bicycle_bic_yes.
I'm wondering if this is something that is desirable for LoMap v4 maps?
I'm not 100% sure why this was done, but is does mean that you can OR together many tags and check for specific instances of common values like ft_yes or bic_yes.
Perhaps this is now resolved with the bugfix to the double tag issue mentioned earlier?

[Andrew Heard]

4.14.2.4: after crashing with previous beta .3 & revert to public APK, I took the risk & installed latest anyway - and so far none of the previous issues with black screen or freezing - well done @menion.

[voldapet]

@karlchick

Thank you for the detailed description. To your points:
I created a new PR that summarizes your suggestions. Please check if acceptable. BTW: repo is public so feel free to participate and create your own pull requests  .
https://github.com/asamm/lomaps-mapsforge/pull/3/commits/194b33ca583a385f973a32db2ea8b83507376bf7

Point 1
- make sense, added
BTW: are there any standard symbols or styles that indicate designation in the UK maps?

Point 2
- added but I'm not sure if tags access_land, public_cycleway, green_lane will be used ...

Point 3
- I would like to avoid using '*' for such elements. I have therefore selected the most important / most used types

Point 4
- the LoMaps V3 was generated as 512x512 tiles and zoom or area is really "shifted" in comparison of 256x256 V4 tiles. There were minor changes in `zoom-appear` attribute for some elements. But it was mainly for zoom-levels 9 - 10 (I think). Do you have some specific requests to change the zoom-appear for certain elements?

Point 5
Well, everything is possible. But there are so-called JohnThorn maps in Locus Store. These maps combine OSM data with OS open data. John Thorn created powerful tools to combine the data but the theme would be (IMHO) a little bit better. What about contacting John and discussing with him a better theme?

Point 6
To be honest I don't know the exact reason for `foot=ft_yes` and `bicycle_bic_yes` but it was very likely because bug in tag matching in Mapsforge as menion already mentioned. This problem is solved https://github.com/mapsforge/mapsforge/pull/1366 (currently only in Locus and waiting for the new official release of mapsforge.)