[mkgmap-dev] Work in progress and the mdr2 branch

Thu Feb 10 11:35:39 GMT 2022

Hi all,

during the last days I've mainly rewritten GPXSee code in Java to be able to understand all the new structures in NT format.
I am making progress but it will probably take weeks until I really understand any of it.
The code in GPXSee is written to be very fast and it silently stops reading whereever bits or bytes have unexpected values,
something that we cannot do when we want to be able to write that format.
Most confusing for me is that it reads parts of the NOD file backwards (at least I think that is what class BitStream4R does).
Anyway, while debugging I see data that looks correct, e.g. some road geometry and labels match the data shown in GPXSee, so
I think it's just a matter of time to get to the point where GPXSee is now.

I wonder if I should try to merge the mdr2 branch into trunk first? 

It's major changes so far are:
- ability to use Huffman compression MDR15 (the string table in the global PC index *_mdr.img)
- different (hopefully better) handling of mixed cased labels (--lower-case option)
- changes from the faster-mp branch
- possibly more memory needed to write global POI index (mdr11)
- default style change to not render natural=coastline as line (*)
- reduced I/O because no strings temp file written for gmapsupp index (*)

(*) It would be quite easy to do this in trunk as well without merging the rest of the changes

Gerd