If you have byte-level chops then the most efficient call would be to ask for ST_AsBinary(geom) and then handle the well-known-binary byte array on your end. There's some WKB example code in the source repo, and also in the MapServer PostGIS connector. But it's a pretty easy format.
P. On Thu, May 26, 2011 at 11:30 AM, SixDegrees <[email protected]> wrote: > > I'm quite new to GIS in general and PostGIS/Postgres in particular. I have to > write a C/C++ routine to dredge values out of an existing PostGIS-enabled > database. For the most part, this seems straightforward, but I can't figure > out how to access the members of types stored as points. > > I'm aware of the ST_X() and ST_Y() SQL functions, but it using these seems > to require two queries. Is it possible to extract the point type into a > C/C++ struct/class with one call to the DB and process the results, or do I > have to make two calls for each point? I can't seem to find a PostGIS API; > does such a thing exist? > > A short example would be much appreciated, if possible. > > Thank you. > -- > View this message in context: > http://old.nabble.com/New-to-PostGIS---Simple-Question-tp31710695p31710695.html > Sent from the PostGIS - User mailing list archive at Nabble.com. > > _______________________________________________ > postgis-users mailing list > [email protected] > http://postgis.refractions.net/mailman/listinfo/postgis-users > _______________________________________________ postgis-users mailing list [email protected] http://postgis.refractions.net/mailman/listinfo/postgis-users
