[Tilecache] Question about tilecache_seed.py with center locations

[Andrew Wooster]

Hi all,

I'm attempting to use tilecache_seed.py to seed the cache using the center
point/radius mode, and am having some difficulty.

My configuration looks like:
[osm]
type=Mapnik
mapfile=/Users/andrew/Projects/OSM/mapnik_osm/osm.xml
spherical_mercator=true
tms_type=google
metaTile=true
metaSize=3,3

And I'm trying to use tilecache_seed like so:
$ python tilecache_seed.py osm
25.791111,55.942778,0.08
^D

I'm using the SVN trunk, and this is happening both on OS X 10.5.3 and
64-bit Ubuntu 8.04 LTS Hardy Heron.

Sadly, it appears that the cache is not being seeded properly with this
method. As near as I can tell, at each zoom level it attempts to seed (5 -
16), it's picking the maximum tile position for both x and y at zoom z-1.
So, for zoom 5, it's attempting to seed tile (16, 16, 5). For zoom 16 it's
attempting to seed tile (32768, 32768, 16). The corresponding bounding
boxes are "(16, 16, 5), (16, 16, 5)" and "(32768, 32768, 16), (32768,
32768, 16)", which also seems odd.

It's also worth noting that seeding with the bounding box method fails
similarly, but seeding with:
$ python tilecache_seed.py osm 5 10

works fine.


If anyone has any ideas as to why this is failing in this configuration,
I'd love to hear them. In the meantime, I'm just starting to dig into the
internals of tilecache, and will keep trying to figure this out.

Thanks,

-Andrew