Hi On 04/09/09 10:16, Steve Hosgood wrote:
"I<hex number>.GMP". Does anyone know how the<hex number> is derived please? I guess that it is a bit-interleave of the latitude and longitude of some reference-point in the tile, but it could be a byte-interleave, or a nybble-interleave, or the interleave is done with the number expressed in decimal or whatever.
I don't think there is any big significance to the names, they can be fairly arbitrary strings.
I guess mkgmap must generate tiles too, so this info is likely well-known to those involved in the code.
We just use digit only names and the number is assigned by the mapmaker, or the tool they use to split the map. ..Steve
BTW: I gather that is possible for subtile files to be given decimal-based filenames too. How does that work? Is there any difference in the actual files depending on the naming system used?
Yes that is what mkgmap does. I don't think it makes any difference to anything else.