Ralf Kleineisel wrote:

On 03/13/2010 11:04 PM, Daniela Duerbeck wrote:

I tried on several maps, [...] it seems to be dependent from 
where I am. A road which is nearby can be found, but not one that is 
farer away.


You can first search for the city in the city search. Then you can
search for the street with the "near here" search.

As far as I can see (with a Streetpilot i3) the street-search offered after you select a 'city' will only find streets within about 500m of the "place=city/town/whatever" marker. ( This is using a single-tile map straight from mkgmap. )

Currently, mkgmap's output .IMG file doesn't include an .MDR file (which is a kind of master-index). You *can* get mkgmap to generate an .MDR file, but it's the "wrong sort" for direct use in a Garmin GPS unit. What you have to do is to feed mkgmap's .IMG file and the matching .MDR file into 'mapsource' and get it to download the maps to the GPS unit.

Allegedly, that makes the street-searching work properly.

I have made a start on writing a stand-alone program to do what 'mapsource' does to convert the .MDR file to one that will work with the in-car units. However, I have a job and a family and cannot put the hours into the project that maybe I'd like. I do have some progress. But of course it's not just about writing a program, it's about deciphering the format of the .MDR file at the same time.

I tend to write up my findings on the .MDR file on the wiki at http://wiki.openstreetmap.org/wiki/OSM_Map_On_Garmin/MDR_Subfile_Format

Anyone else with knowledge of the file format is encouraged to join in!

Steve