Thread: PyMapper (a maemo-mapper knock-off)
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rtaranu is offline rtaranu
2007-10-12 , 11:57
Posts: 6 | Thanked: 0 times | Joined on Oct 2007
#22
Originally Posted by penguinbait View Post
It was implied, but either way I am sure the corruption issue was the fault of the kernel bug.

Help me understand this, stored in db or on FS, your still writing the same amount of data right? perhaps a tad more with the db because you have an index. It may however take less room on the fs because of block size, but each tile is still written.

Am I missing something on how this helps the memory card? Is it the memory in the db being used as cache, still writing the same amount to the card???

I am sure metalayer-crawler will like this much better that maemo-mapper current fs layout..
You are right about the space saving, it's the block size thing. You can see how much space you'd save if you connect the Nokia to a Windows machine using USB and go to the repository folder's properties. It shows the "size" and "size-on-disk". Also, copying files to and from the Nokia is very slow for me when you deal with many small files, one single file works much faster.

About how it is better for the mem-card: not sure, all I can tell you is that I haven't managed to corrupt the mem-card yet.

But I can give you a list of advantages for using a db + python:

This is multi-platform, I actually developed this whole thing on my windows machine, and it ported without a hitch, I just had to change the "keyboard" event listeners. Ok, maybe not that easy, because I found many bugs in my code due to the Nokia being very slow, but the code did port right over without many issues.

If it's multiplatform, you can use your PC to download all the maps you want (faster) and just copy a database file over to the Nokia. You can also use this on win / linux / mac os without any complicated work.

DB is practical, because you can make "map sets". So when you go on a road trip and you need to cache a lot of tiles, you can erase them easily when you are done.

The project was actually started to be able to make custom maps. I was looking for a GPS / mapping device for marine applications and they are all very expensive (1000$+). But normal paper maps are 30$. My plan was to scan a paper map every year (since they change) and to import them into PyMapper. I'm still working on that idea, but the boating season's mostly over where I live and I'm not in a big rush till spring.
Last edited by rtaranu; 2007-10-12 at 12:01.