[mkgmap-dev] Fwd: resolution and zoom levels in style files

Fri Feb 26 06:02:25 GMT 2010

Daniela Duerbeck wrote:
> I think there are a few problems for a beginner like me:
>
> I have 27 zoom levels on my Garmin device.
> I have 24 levels for resolution in the style file
> I have 8 mappings of resolution to levels in the options file.
>
> I learned that some levels on the device show "overzoom" so that they 
> are not to be counted.
>
> And, not to forget the option on the device: show more or less details.
>
> That makes everything a bit confusing, even if the resolutions in the 
> options file match exactly them inside the other files. :-)))
>
> Dani
>   
gpsmapedit gives approximate equivalents that work with default detail 
levels. For example in one of my maps I have Level0=24 bits, which is 
equal to a grid of 2.4m, a GPS zoom level of 120m or a MapSource Zoom of 
under 1.2km.

Bits - grid - GPS-MapSource
24 bits - 2.4m - 120m - <1.2km
22bits - 9.5m - 500m - 1.2 to 3km
20bits - 38m - 2km - 3 to 8 km
18bits - 153m - 5 to 8 km - 8 to 12 km
16bits - 610m - 20 to 30 km - 12 to 30km
15bits - 1.22km - 50 km - 50 -100km

Garvan