mkgmap and zooming

General talk
1

Hi folks,

I’m trying to customize Garmin map created by mkgmap using modified mkgmap default style (some points added and zoom levels are redefined). I’m lost trying to figure out why some points are appearing on the map on zoom levels, on which I think these points should not be present - these points are appearing on a less detailed maps, even when I’m using resolution 24. I’ve used 3 different mkgmap versions: stable (r1188), r1466, r1473 and the result is always the same. mapedit from http://www.geopainting.com/en/ seems to show points on generated maps correctly, my Garmin device not. I’m using Garmin Legend HCx, latest update. Extracts from config files:

options:
levels = 0:24, 1:22, 2:21, 3:20, 4:19, 5:18, 6:16, 7:12

points:
amenity=bench [0x004a level 0]
highway=bus_stop [0x2f08 level 5]

Bus stop icon disappearing on a more detailed zoom level then Bench, I expected it to be vice versa. Can anyone please confirm that this configuration is correct ?

Thanks in advance

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2

Two things:

  1. Have you tried using resolution instead of level in your style file:
    amenity=bench [0x004a resolution 24]
    highway=bus_stop [0x2f08 resolution 18]

  2. Garmin GPS units often have their own ideas about what resolutions certain things will appear at, no matter what you stipulate in your style file.

Things are further complicated by the fact that you can alter the detail of the map. Each extra degree of detail you select “moves” everything up one zoom level. Declutter option also affects this, as does the setting where you can decide the minimum zoom level at which POIs occur. But of course these latter settings should affect both POI types equally.

3

There are some poi types that disappear very early depending on GPS type or Mapsource (version).

4

I have used the range of 16nn 19nn and 1bnn, they seem to have normal behavier.
You can change the ID of the bench, if this Point makes the problem.
Since you would like to have the bus_stop in your POI-Liste, changing this ID will be no option.

Some IDs like 67nn are show very early and also 1dnn has some special behavier.
Just try to change the ID-Group.

5

Yes, I’ve tried both, and I’ve tried resolution before trying levels.

I have used pure mkgmap without any generated .typ files. I thought that it is probably device itself, which is interpreting settings differently from the mapsource or mapedit.

Anyways, my idea was to show almost all the points on the map (for mapping purposes), but define particular zoom levels for all these points (for overview while travelling). For example - museums and bus stops should appear on less detailed zoom levels with proper Icons, and benches, barriers on a more detailed map zoom levels. Some of the POIs which appears on an unwanted zoom levels are the ones from the default style and were unmodified, but I assume there is no 100% reliable spec for the behaviour of all POIs available. And all POI definitions I has added to the default style are shown incorrectly. I’m aware of the sf.net project with the spec for the .img format, probably reverse engineered information, but I haven’t went through it, to much details for me at this time.
I have used following options to generate the map, if this can help:


java -jar -Xmx384M ../mkgmap-r<#>/mkgmap.jar --style-file=./ezm.zip \
--check-roundabouts --check-roundabout-flares \
--drive-on-left --make-all-cycleways --generate-sea=multipolygon --add-pois-to-areas \
--gmapsupp --ignore-osm-bounds --net --route --mapname=31107908 \
reading.osm

I’ll play a bit with options, but I have spent already to much time on this.

csdf: Thanks for your web page, it is really useful in terms of using mkgmap.

Guys, Thanks for help, generated maps are working for me anyways…

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