using mkgmap to change zoom level details

Interesting, I follow this.

Ive not worked at mkgmap level, but used other tools to merge my own edited typ files into existing img files.

I did manage to get some joy out of using the mkgmap style settings to change the zoom levels. It worked for one garmin device, the Dakota hand-held. Haven't dared try it on the fenix yet... 

What tools do you use?

The tools I used:

• GMapTool
• TYPviewer
• TYPchanger

Some more info on what I've tried, with some success.

mkgmap is a java utility to convert OSM maps into Garmin .img files.

You can get it from Background (mkgmap.org.uk)

You run it using:

java -jar mkgmap.jar file.osm

There’s a README and some good doco at the website i got it from about style settings.

You can extract OSM maps in various ways (Google it) and then run mkgmap on them to make .img files for Garmin devices.

Using mkgmap to change what zoom levels nodes are visible at

Conversion Style manual (mkgmap.org.uk) says that “You can completely change which features are displayed and at what zoom levels.” which sounds perfect for getting around the ‘huts not visible until you zoom right in’ problem on the Fenix 7.

To do this you need to edit the files in a style directory (see examples\styles\default in the download and change the resolution for some node type, e.g. tourism=camp_site

I looked into my OSM map  and I see that there’s a node with tag k=name v=Rock Shelter and tag k=tourism v=camp_site so I edited the points style file in examples/default and changed

tourism=camp_site [0x2b03 resolution 20] [0x2b05 resolution 20] #TC changed res to 20 from 24 as a test

and then open a cmd window and run  (obviously this will be different for other osm maps and dowload locations etc)

cd d:\mkgmap

d:

java -jar mkgmap.jar --style-file=D:\mkgmap\examples\styles\default --description=GwinearTest D:\maps_OSM\gwinear\gwinear.osm

It produces a bunch of .img files in and the one you want is called 63240001.img. Copy that to /Garmin folder of the target device. Then choose that map on the device.

Note that I tried looking at the map with basecamp and the edits seemed to have to effect.

In a Dakota gps hand-held however, they did. When resolution set to 24, camp_site nodes only appeared for scales of 800m or less and disappeared above that. When I changed resolution to 18, the camp_site nodes stay visible up to scales of 54km!

Ta, I'll take a look! Meanwhile I just posted something I tried that kinda worked.

I tested this use of mkgmap to increase visibility of camp_site nodes when zoomed out, on the fenix 7. It does NOT work.

Unlike on the Dakota hand-held GPS, campsites don't show up when I zoom out past 80m. This despite me setting the resolutin of camp_site nodes to 18. (The correspondence between resolution setting and zoom level or scale is complicated but basically setting res to 18 instead of 24 should make camp_site nodes be visible for more zoomed outedness.) It doesn't appear to work on the Fenix like it did on the Dakota. Pooh.

Thanks for all info.

My interest has before been just to see the styles from an existing osm provider to see what obects they have inluded and I can manipulate with a new typ-file.

I think I now have the courage to go all the way.

What I have found that is more promising than the resolution is that the identifying hex number for the node's icon has a great effect on visibility at different zooms, on the Fenix 7. If, in the 'points' file that mkgmap uses, I change the rule for camp_site nodes to 

tourism=camp_site  [0x4a00 resolution 24]    #I.e. I have used hex 0x4a00 to set the icon rather than 0x2b05

then the picnic table icon that 0x4a00 apparently represents replaces the tent icon previously there and is visible at the camp_site for scales up to 300m. (up from 80m with the tent icon) This is the scale on the watch at which walking tracks first become visible, so not too bad. (Though I'd prefer even higher level vis...)

So, I just need to identify the hex number for a suitable icon for camp_site (and tourism=wilderness_hut and similar)  that has a high visibility.

Do you have those two in your typ file?

Or are the default symbols used?

I dont remember how the matching between style and typ was done. Is it on hex or the text (camp_site)?

Have you seen any complete doc regarding symbols in img?

They are built in symbols and codes I think.  I'm still looking for good doco. There's a Wikipedia article wiki.openstreetmap.org/.../POI_Types