NAME
Math::Geometry::Planar::GPC::Polygon - OO wrapper to gpc library
Status
Successfully used in minor production use under perl 5.6.1 and 5.8.3. Your mileage may vary (see NO WARRANTY.)
AUTHOR
Eric L. Wilhelm
ewilhelm at sbcglobal dot net
http://pages.sbcglobal.net/mycroft/Copyright
Copyright 2004 Eric L. Wilhelm
License
This module and its C source code (functions.c) are freely redistributable under the GNU general public license (GPL). See http://www.gnu.org for details.
The General Polygon Clipping library (gpc.c and gpc.h) is also distributed under the GPL license. A copy of these files has been included with this distribution strictly for convenience purposes. See gpc.c for details. Note that the C library is authored by Alan Murta.
You may want to check the GPC home page for a more current version:
http://www.cs.man.ac.uk/aig/staff/alan/software/Portability
This module successfully compiles on i386 and solaris architectures according to the cpan testers results. Hopefully, versions after 0.04 will work on WIN32. I don't have any non-linux machines, so feel free to send patches.
NO WARRANTY
This code comes with ABSOLUTELY NO WARRANTY of any kind.
Changes
0.01 - First public release.
0.02 - Added API documentation.
0.03 - Fix to allocation error.
Possibly Fixed WIN32 compile problem?
0.04 - Twiddling with WIN32 compile problem (last try)Constructors
new
Traditional constructor, returns a blessed reference to the underlying C struct.
use Math::Geometry::Planar::GPC::Polygon;
my $gpc = Math::Geometry::Planar::GPC::Polygon->new();new_gpc
An optionally imported constructor, for those of you who don't like to type so much.
use Math::Geometry::Planar::GPC::Polygon qw(new_gpc);
my $gpc = new_gpc();Bound Functions
These are the functions provide by the Inline-C code. See functions.c in the source package for intimate details.
from_file
Loads a from a file into your gpc object. See the GPC library documentation for details.
$gpc->from_file($filename, $want_hole);to_file
Writes to a file.
$gpc->to_file($filename, $want_hole);clip_to
Clips the $gpc object to the $othergpc object.
$action may be any of the following:
INTERSECT
DIFFERENCE
UNION
$gpc->clip_to($othergpc, $action);Be wary. This interface may need to change.
add_polygon
Adds a polygon to the gpc object. @points is a list of array references which describe the point of the polygon. $hole is 1 or 0 (0 to not add a hole.)
$gpc->add_polygon(\@points, $hole);get_polygons
Gets the polygons from the gpc object. I'm not sure how to tell you if they are holes or not. @pgons will be a list of refs to lists of refs.
@pgons = $gpc->get_polygons();Helper Functions
Pure-perl implementation from here down.
as_string
$gpc->as_string();