Hi Rob, Thanks for your email! My replies inline below.
On Apr 4, 2012, at 12:23 PM, Rob Battle wrote: > Chris, > > I am the primary developer of the GeoSPARQL index in Parliament. The spatial > part is certainly pluggable. We have an interface for the index and have > implemented it with a variety of backends including a persistent RTree from > the degree project [1], PostgreSQL w/PostGIS [2], and an in-memory quad tree > using JTS [3]. Gotcha, OK. > One part that is not pluggable is the query engine for for Parliament (which > replaces the default ARQ query engine). We optimize the query such that the > parts of the query that can be answered more efficiently by the spatial index > are executed first. We would certainly consider using SIS if it could be > easily integrated and provides better performance than what we are currently > using. Cool. I'm not sure SIS will be more efficient than JTS, but SIS is ALv2 licensed, so it will at least carry with it less virality and won't cause your own software to be LGPL (or GPL), in a copyleft fashion. And, there are a budding number of people here and a positive community of many people who are interested in helping you solve use cases that are interesting and challenging. > TBH I hadn't heard of it before I saw this thread. No worries. We're trying to grow a community here at Apache and it's been slow, but extremely positive and a great overall experience. > > Unfortunately, I'm not sure if our implementation is ALv2. Parliament is BSD > licensed and some of the libraries we link to are LGPL. Depends on the version of LGPL, and specific instances, but what is known is that JTS brings with it LGPL dependencies and virality, with respect to licensing. There are different ways you can link against it, and legal "syntactic sugar", but rather than worry about that, we're trying to be an ALv2 "clean" version of similar functionality. And I (specifically, because we're all individuals here at Apache that have our own "itches" to scratch) am interested in a real use case for SIS beyond Quad Tree and our simple GMaps demo...GeoSPARQL sounds like a great use case! Cheers, Chris ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Chris Mattmann, Ph.D. Senior Computer Scientist NASA Jet Propulsion Laboratory Pasadena, CA 91109 USA Office: 171-266B, Mailstop: 171-246 Email: [email protected] WWW: http://sunset.usc.edu/~mattmann/ ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Adjunct Assistant Professor, Computer Science Department University of Southern California, Los Angeles, CA 90089 USA ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
