[Mapserver-users] Shapelib, GPC, PHP, and polygon clipping

Ryan, Adam ARyan at co.linn.or.us
Fri Apr 30 20:38:04 EDT 2004


Steve, Frank, etc...

A while back Steve Lime wrote in response to a request for polygon clipping
code.

http://mapserver.gis.umn.edu/data2/wilma/mapserver-users/0201/msg00094.html

He suggested using the GPC library.  I checked this out and was able to get
it to work.

Is it worth trying to use GPC with either PHP mapscript or shapelib directly
and  write a little routine to grab the shapes in question, convert them to
gpc ascii format, run the clip operation, and convert back to a shapefile
result?  In PHP I could build the ASCII files, then call a gpc executable,
and then translate the ASCII result back into a new shapefile.

Am I exploring old technology?  Is there a better way?  Seems like a lot of
steps but all the really hard work has been done and it's just a matter of
reformatting data to work with the different tools.

I'd like to explore PostGis but we're a Windows shop and it's not in the
cards.

Thank you for any suggestions you might have,

Adam Ryan
GIS Analyst
Linn County GIS Department
Albany, OR 97321
aryan at co.linn.or.us
 



More information about the mapserver-users mailing list