I'm preparing to upgrade an installation of Postgis in the near future and am
looking forward to trying out SFCGAL due to its robustness improvements for
PostGIS functions. However, as I am not an expert on the intricacies of
software licenses, I was extremely confused by the dual GPL/LGPL license
terms of CGAL upon which SFCGAL and Postgis now depend.
So my question is, does standard use of a Postgis database within the
context of a standard commercial web application, (querying it via SQL from
Java JDBC, filling it with data, returning data to app, etc.) require an
industrial license for CGAL or the release of source code for the app that
queries the database -or would that only apply if I modified CGAL itself
since SFCGAL is LGPL?
I'm assuming the latter since SFCGAL is now the default for functions like
st_intersects() which are pretty core to Postgis -and is included by default
with the liblwgeom package on Ubuntu 16.04; however I figured it's worth
clarifying with devs before I try it out, find that it solves my
longstanding issues with st_union() robustness and the dreaded "found
non-noded line string" error messages that have regularly thwarted my SQL
statements since 2012 -only for my heart to be crushed into oblivion knowing
that I can't actually use it in the app that I work on! That was my
experience after graduating college having worked almost entirely with ESRI
tools, learning all of the functions and their quirks and nuances, then
being abruptly hit with the realization that they are too expensive to use
in the real world unless you work for a large institution or corporation
(which is how I discovered PostGIS in the first place).