Paul,
Thanks for sending this my way. I'll pipe in and provide a little
background on SDF. You guys can then decide if it's the right format or
uDig or not.
SDF stands for Spatial Database Format. It supports multiple feature
classes per file with fully typed properties and multiple geometry
properties per feature class. Each geometry property is indexed via an
R-Tree. As for spatial operations, the SDF query engine supports
Intersects, Contains, Within, Disjoint, and Inside.
The format is built on SQLite, but does not use any of the relational
aspects of SQLite, hence you cannot use any of the SQLite client tools
for viewing / querying an SDF file. We are just using the low level
storage components of SQLite.
If you have questions or want more details on any of this just respond
on the udig-devel list, I joined that list today.
