[mkgmap-dev] r4006: 1st alpha version to write DEM data

Tue Dec 19 23:28:59 GMT 2017

Hi Gerd,

great news!

 > It will crash if any hgt file is missing
I have them all, but there is no HGT for sea area, missing files is a 
standard case.

 > I did not check if the flags in the tdb file are set correctly now
I didn't check either, but tdb created by mkgmap v3999 works correctly 
for maps with DEM.

 > My currennt understanding is that mkgmap should do the calculation of
 > the DEM resolution based on the levels used to create the rest of the
 > map.
I think it should be like that and some Garmin maps follow this rule. I 
have tried to create DEM with pixel size ratio like 1:4:16:64 for levels 
24,22,20,18. It didn't work correctly in Mapsource. What works for me is 
ratio 1:2:4:8. I think some of unknown fields in DEM header could 
contain this ratio. It is something to investigate further.

-- 
Best regards,
Andrzej