This is so not the first post of this type, and will not be the last. Please note that this was written quickly, and I may have left something out from our discussion, or possibly been inaccurate, so please feel free to correct or add. This topic is definitely owed a more complete post, but it will have to be post DrupalCon.
Yesterday, at DrupalCon Copenhagen, we had a BoF on Geo-Goodness and Drupal where we discussed what is going on in this space, what things could/should happen, and what can be done to make Drupal the Drupal GeoCMS or something close.
Overall, the discussion was very ad-hoc, just trying to get stories of experience people had using modules, and picking modules, and what that means for the developers.
What we decided on are the following:
Documentation
There will be a documentation sprint for the following things tomorrow at the Code Sprint (Fri 27 Aug 2010, Copenhagen). I will be around to help direct people, but have some prior engagements for coding.
- Analysis of the module space for geo-related projects. What is out there? What does what? What works with what? what is the status of the projects? etc. I have agrede to start a wiki page for this, but will need a lot of collaboration to create a full picture.
- Recipes, Use Cases, Case Studies. More example based documentation, as most users can not think in the theoretical and find practical examples better learning tools.
The Stack
The Drupal Geospatial stack probably involves the following parts. There could and should be competing modules in most of these spaces, but they should be able to be switched out easily.
- Data storage
- Collection/Input
- Display
Data formats
A common data format of geospatial data to pass around Drupal would probably be beneficial. Allie has brought this up before, but no action from the community was taken on it. My suggestion was for Geo module to define this and it can be refined moving forward, if necessary.

Comments
Common data format
FYI, I've been adding PHP binding to libgeos (http://trac.osgeo.org/geos/) specifically to help in having a common, standard and fast way to deal with geometries in PHP.
I know for many a module dependency is too much, but note that GeoDjango is using libgeos too, trough shapely so I belive Drupal will lag behind if doesn't start doing the same :)
PHP Extension
Just talked with Markus, manarth about his work, which is creating a native PHP extension for data types. Need to start getting folks talking. Just wanted to get this down somewhere.
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zzolo
Geospatial Module Assessment Wiki Page
Created new wiki page about module assessment. Still needs lots of work: http://groups.drupal.org/node/89769
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zzolo
@zzolo. Great idea, new users
@zzolo. Great idea, new users are often totally confused and are all having a hard time finding the projects and how they all fit into the bigger picture. A map of mapping projects ;)
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Stein Magne
http://smbjorklund.com
Great idea!!
Great idea zzolo!
I've already included the field for the Mapstraction CCK module.
Thanks ;)
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Pablo López, Drupal developer
https://twitter.com/plopesc
Mapstraction added
Thanks zzolo, this is definitely needed.
Lev Tsypin
ThinkShout, Inc.
thinkshout.com | twitter.com/levelos