NAME

Geo::Geos::Algorithm - Fundamental computational geometry algorithms.

SYNOPSIS

# imports constants: TYPE_TURN_CLOCKWISE, TYPE_TURN_COLLINEAR, TYPE_TURN_COUNTERCLOCKWISE
# TYPE_ORIENT_RIGHT, TYPE_ORIENT_LEFT, TYPE_ORIENT_STRAIGHT
use Geo::Geos::Algorithm;

use Geo::Geos::Algorithm qw/toRadians toDegrees angle isAcute isObtuse angleBetween getTurn
                       angleBetweenOriented interiorAngle normalize normalizePositive diff
                       centroid centroidArea centroidLine centroidPoint/;
use Geo::Geos::Algorithm qw/isPointInRing locatePointInRing isOnLine isCCW computeOrientation
                       orientationIndex distancePointLine distancePointLinePerpendicular
                       distanceLineLine signedArea getIntersection convexHull
                       interiorPointArea interiorPointLine interiorPointPoint
                       locate intersects signOfDet2x2
                       locateIndexedPointInArea locateSimplePointInArea/;

use Geo::Geos::Coordinate;
use Geo::Geos::GeometryFactory;

# Angle
my $c01 = Geo::Geos::Coordinate->new(0,2);
my $c02 = Geo::Geos::Coordinate->new(0,0);
my $c03 = Geo::Geos::Coordinate->new(1,1);

toDegrees(toRadians(90));                      # => 90
angle(Geo::Geos::Coordinate->new(1,0));        # => 0
isAcute($c01, $c02, $c03);                     # => success
isObtuse($c01, $c02, $c03);                    # => ''

my $a1 = angleBetween($c01, $c02, $c03);
toDegrees($a1);                                # => 45

my $a2 = angleBetweenOriented($c01, $c02, $c03);
toDegrees($a2);                                # => -45

my $a3 = interiorAngle($c01, $c02, $c03);
toDegrees($a3);                                # => 45

my $a4 = normalize(toRadians(90) * 3);
toDegrees($a4);                                # => -90

my $a5 = normalizePositive(toRadians(90) * 3);
toDegrees($a5);                                # => 270

my $a6 = diff($a2, $a3);
toDegrees($a6);                                # => 90

getTurn($a1, $a2);                             # => TYPE_TURN_CLOCKWISE;


# Computational Geometric algorithms.
my $c1 = Geo::Geos::Coordinate->new(1,2);
my $c2 = Geo::Geos::Coordinate->new(5,2);
my $c3 = Geo::Geos::Coordinate->new(5,0);
my $c4 = Geo::Geos::Coordinate->new(1,0);

my $coords_ring = [$c1, $c2, $c3, $c4, $c1];

isPointInRing($c1, $coords_ring);      # => success
locatePointInRing($c1, $coords_ring);  # => is 1
isOnLine($c3, [$c1, $c2]);             # => ''
isCCW($coords_ring);                   # => ''
computeOrientation($c1, $c2, $c3);     # => TYPE_TURN_CLOCKWISE
orientationIndex($c1, $c2, $c3);       # => TYPE_TURN_CLOCKWISE

distancePointLine($c3, $c1, $c2);                  # => 2
distancePointLinePerpendicular($c3, $c1, $c2);     # => 2
distanceLineLine($c1, $c2, $c3, $c4);              # => 2

signedArea($coords_ring);                           # => 8
Geo::Geos::Algorithm::length([$c1, $c2, $c3, $c4]);      # => 8

# CentralEndpointIntersector
getIntersection($c1, $c2, $c3, $c4); # => isa 'Geo::Geos::Coordinate'

# ConvexHull
my $gf = Geo::Geos::GeometryFactory::create();
my $lr = $gf->createLinearRing($coords_ring, 2);
convexHull($lr);  # => isa 'Geo::Geos::Geometry'

# InteriorPoint
my $p = $gf->createPolygon($lr);
interiorPointArea($p);     # => isa 'Geo::Geos::Coordinate'

my $ls = $gf->createLineString([$c1, $c2], 2);
interiorPointLine($ls);    # => isa 'Geo::Geos::Coordinate'

my $point = $gf->createPoint($c2);
interiorPointPoint($point);    # => isa 'Geo::Geos::Coordinate'

# PointLocator
locate($c2, $lr);      # => is 0
intersects($c1, $lr);  # => success

# RobustDeterminant
signOfDet2x2(1,2,3,4);     # => -1

# Locate
locateIndexedPointInArea($c2, $p);     # => 1;
locateSimplePointInArea($c2, $p);      # => 0;

EXPORTS CONSTANTS

TYPE_TURN_CLOCKWISE

TYPE_TURN_COLLINEAR

TYPE_TURN_COUNTERCLOCKWISE

TYPE_ORIENT_RIGHT

TYPE_ORIENT_LEFT

TYPE_ORIENT_STRAIGHT

SEE ALSO (C++ classes docs)

GEOS C++ Library

geos::algorithm::Angle

geos::algorithm::Centroid

geos::algorithm::CentroidArea

geos::algorithm::CentroidLine

geos::algorithm::CentroidPoint

geos::algorithm::CGAlgorithms

geos::algorithm::CentralEndpointIntersector

geos::algorithm::ConvexHull

geos::algorithm::InteriorPointArea

geos::algorithm::InteriorPointLine

geos::algorithm::InteriorPointPoint

geos::algorithm::PointLocator

geos::algorithm::RobustDeterminant

geos::algorithm::locate::IndexedPointInAreaLocator

geos::algorithm::locate::SimplePointInAreaLocator

SEE ALSO

Geo::Geos

Geo::Geos::Algorithm::HCoordinate

Geo::Geos::Algorithm::LineIntersector

Geo::Geos::Algorithm::MinimumDiameter

Geo::Geos::Coordinate

AUTHOR

Ivan Baidakou <i.baydakov@crazypanda.ru>, Crazy Panda, CP Decision LTD

LICENSE

You may distribute this code under the same terms as Perl itself.

cpanm Geo::Geos

perl -MCPAN -e shell
install Geo::Geos