[pdal] GEOS support

[Howard Butler]

> On Jun 4, 2015, at 3:13 PM, Matt Hanson <matt.a.hanson at gmail.com> wrote:
> 
> Hello, 
> 
> I wanted to crop a point cloud with a polygon.    cmake on PDAL (current master) reports GEOS under "OPTIONAL packages have been found", however when I try to crop a polygon in my xml file it says:
> 
> PDAL: Polygon cropping not supported unless built with GEOS
> 
> Do I need to explicitly tell PDAL to build with GEOS support?

Crop filter isn’t a plugin, because it works without having GEOS linked in box mode. PDAL_HAVE_GEOS must be defined in ./include/pdal/pdal_defines.h to have GEOS support enabled. If that is commented out, your GEOS is not being used for some reason. Maybe there is some kind of cmake configuration bug that we have in regard to this.

`pdal --debug` will also show if it thinks your GEOS is linked.

Hope this helps,

Howard