From steven at minst.net  Thu Sep 15 11:22:37 2011
From: steven at minst.net (Steven Ottens)
Date: Thu Sep 15 23:44:01 2011
Subject: [Tiling] BoF notes
Message-ID: <DBE255BA-6ED0-418E-BA31-6ABB416206F2@minst.net>

Hi all,

Thanks for those who could make it to the BoF. It was an interesting discussion. I've made some notes, please correct me when I'm wrong or lacking, since I've not captured the complete discussion.
We mainly discussed the need for a way to transport tiles between servers and/or software.

We had a short discussion on using postgis raster or berkley db for tilestorage. It turns out that they are not very suited for the above purpose.

So the discussion moved to SQLite
The MBTiles standard is a good example what we like to see. Except that it is a too restrictive specification. It only supports spherical mercator and only one layer.

We came up with this:
A simple one table database with x/y/z/image-blob (per layer)
A config.db which will contain metadata like the layernames, tileschema and the table/db which have the actual tiles

This way we can provide single file databases by putting the data in the config.db but also allow for more scalable solutions with multiple databases per layer.

Regards,
Steven