[Tilesathome] Lowzoom Place Labels displaced

[Sebastian Spaeth]

80n wrote:
> I wonder if there has been some kind of Lowzoom regression recently?
> 
> This doesn't look right (roads in the middle of the Atlantic):
> http://www.informationfreeway.org/?lat=47.123941534554994&lon=-13.118355439939368&user=80n&zoom=6&layers=B000F000F 
> <http://www.informationfreeway.org/?lat=47.123941534554994&lon=-13.118355439939368&user=80n&zoom=6&layers=B000F000F>
> 
> And the Outer Hebrides has got spots:
> http://www.informationfreeway.org/?lat=57.256443738709635&lon=-8.306344763441256&user=80n&zoom=7&layers=B000F000F 
> <http://www.informationfreeway.org/?lat=57.256443738709635&lon=-8.306344763441256&user=80n&zoom=7&layers=B000F000F>
> 
> And half of Germany has gone:
> http://www.informationfreeway.org/?lat=50.9483202385237&lon=12.106935116925818&user=80n&zoom=6&layers=B000F000F 
> <http://www.informationfreeway.org/?lat=50.9483202385237&lon=12.106935116925818&user=80n&zoom=6&layers=B000F000F>

See my reply to Frederik in another mail.. I checked a missing Germany 
tile and the captionless layer was producing an empty land tile although 
it should not. (see bug 1). if someone could look into this client side, 
I'd appreciate.

2 1/2 reasons:

- There is a bug client side (that I won't be able to look into) that 
makes  "captionless" create one empty land tile, even if the OSM file 
contains loads of stuff. This is even with stable t at h clients. I have 
not looked  deeply into this.
Someone should examine this. I tried e.g.
./tilesGen.pl --Debug=1 --Layers=captionless xy 2208 1376
(this is in Germany)

(Rob also already mentioned some previous client bug which caused black 
tiles, I think that is fixed, not sure)

- I am deleting old legacy tiles and for areas where no new captionless
has been produced yet, it will be replaced by whatever oceantiles.dat
tells us (empty land/sea).

- There is also one bug on the server side (in addition) that somehow
seems to create an "unknown" lowzoom tile if underlying captionless
tiles are not existing. It should fall back to oceantiles.dat
information in these cases and I will look into that next week.

Otherwise nothing has changed in the way we produce lowzoom tiles, so 
regressions are probably on the client side. I'll do a few test lowzoom 
tiles next week.

spaetz