# geos::operation::polygonize::Polygonizer Class Reference

Polygonizes a set of Geometrys which contain linework that represents the edges of a planar graph. More...

`#include <Polygonizer.h>`

List of all members.

## Public Member Functions

| Polygonizer ()
| Create a polygonizer with the same GeometryFactory as the input Geometry.
void | add (std::vector< geom::Geometry * > *geomList)
| Add a collection of geometries to be polygonized. May be called multiple times. Any dimension of Geometry may be added; the constituent linework will be extracted and used.
void | add (std::vector< const geom::Geometry * > *geomList)
| Add a collection of geometries to be polygonized. May be called multiple times. Any dimension of Geometry may be added; the constituent linework will be extracted and used.
void | add (geom::Geometry *g)
void | add (const geom::Geometry *g)
std::vector< geom::Polygon * > * | getPolygons ()
| Gets the list of polygons formed by the polygonization.
std::vector< const geom::LineString * > * | getDangles ()
| Get the list of dangling lines found during polygonization.
std::vector< const geom::LineString * > * | getCutEdges ()
| Get the list of cut edges found during polygonization.
std::vector< geom::LineString * > * | getInvalidRingLines ()
| Get the list of lines forming invalid rings found during polygonization.

## Protected Attributes

PolygonizeGraph * | graph
std::vector< const geom::LineString * > * | dangles
std::vector< const geom::LineString * > * | cutEdges
std::vector< geom::LineString * > * | invalidRingLines
std::vector< EdgeRing * > * | holeList
std::vector< EdgeRing * > * | shellList
std::vector< geom::Polygon * > * | polyList

## Friends

class | Polygonizer::LineStringAdder

## Detailed Description

Polygonizes a set of Geometrys which contain linework that represents the edges of a planar graph.

Any dimension of Geometry is handled - the constituent linework is extracted to form the edges. The edges must be correctly noded; that is, they must only meet at their endpoints. The Polygonizer will still run on incorrectly noded input but will not form polygons from incorrected noded edges.

The Polygonizer reports the follow kinds of errors:

- Dangles - edges which have one or both ends which are not incident on another edge endpoint
- Cut Edges - edges which are connected at both ends but which do not form part of polygon
- Invalid Ring Lines - edges which form rings which are invalid (e.g. the component lines contain a self-intersection)

## Member Function Documentation

void geos::operation::polygonize::Polygonizer::add | ( | std::vector< geom::Geometry * > * | geomList ) |

Add a collection of geometries to be polygonized. May be called multiple times. Any dimension of Geometry may be added; the constituent linework will be extracted and used.

Parameters:

  geomList | a list of Geometry with linework to be polygonized

void geos::operation::polygonize::Polygonizer::add | ( | std::vector< const geom::Geometry * > * | geomList ) |

Add a collection of geometries to be polygonized. May be called multiple times. Any dimension of Geometry may be added; the constituent linework will be extracted and used.

Parameters:

  geomList | a list of Geometry with linework to be polygonized

void geos::operation::polygonize::Polygonizer::add | ( | const geom::Geometry * | g ) |

Add a geometry to the linework to be polygonized. May be called multiple times. Any dimension of Geometry may be added; the constituent linework will be extracted and used

Parameters:

  g | a Geometry with linework to be polygonized

void geos::operation::polygonize::Polygonizer::add | ( | geom::Geometry * | g ) |

Add a geometry to the linework to be polygonized. May be called multiple times. Any dimension of Geometry may be added; the constituent linework will be extracted and used

Parameters:

  g | a Geometry with linework to be polygonized

std::vector<const geom::LineString*>* geos::operation::polygonize::Polygonizer::getCutEdges | ( | ) |

Get the list of cut edges found during polygonization.

Returns:
  a (possibly empty) reference to collection of the input LineStrings which are cut edges. Ownership retained by this object.

std::vector<const geom::LineString*>* geos::operation::polygonize::Polygonizer::getDangles | ( | ) |

Get the list of dangling lines found during polygonization.

Returns:
  a collection of the input LineStrings which are dangles

std::vector<geom::LineString*>* geos::operation::polygonize::Polygonizer::getInvalidRingLines | ( | ) |

Get the list of lines forming invalid rings found during polygonization.

Ownership is tranferred to caller, second call will return NULL (unless polygonize is called again).

Returns:
  a collection of LineStrings which form invalid rings

std::vector<geom::Polygon*>* geos::operation::polygonize::Polygonizer::getPolygons | ( | ) |

Gets the list of polygons formed by the polygonization.

Ownership of vector is transferred to caller, subsequent calls will return NULL.

Returns:
  a collection of Polygons

The documentation for this class was generated from the following file:

- Polygonizer.h