# geos::operation::overlay::OverlayOp Class Reference

Computes the overlay of two Geometry. More...

`#include <OverlayOp.h>`

Inheritance diagram for geos::operation::overlay::OverlayOp:

List of all members.

## Public Types

enum | OpCode { opINTERSECTION = 1, opUNION, opDIFFERENCE, opSYMDIFFERENCE }
| The spatial functions supported by this class. More...

## Public Member Functions

| OverlayOp (const geom::Geometry *g0, const geom::Geometry *g1)
| Construct an OverlayOp with the given Geometry args.
geom::Geometry * | getResultGeometry (OpCode funcCode)
geomgraph::PlanarGraph & | getGraph ()
bool | isCoveredByLA (const geom::Coordinate &coord)
| This method is used to decide if a point node should be included in the result or not.
bool | isCoveredByA (const geom::Coordinate &coord)
| This method is used to decide if an L edge should be included in the result or not.

## Static Public Member Functions

static geom::Geometry * | overlayOp (const geom::Geometry *geom0, const geom::Geometry *geom1, OpCode opCode)
static bool | isResultOfOp (geomgraph::Label *label, OpCode opCode)
static bool | isResultOfOp (int loc0, int loc1, OpCode opCode)
| This method will handle arguments of Location.NULL correctly.

## Protected Member Functions

void | insertUniqueEdge (geomgraph::Edge *e)
| Insert an edge from one of the noded input graphs.

## Detailed Description

Computes the overlay of two Geometry.

The overlay can be used to determine any boolean combination of the geometries.

## Member Enumeration Documentation

enum geos::operation::overlay::OverlayOp::OpCode

The spatial functions supported by this class.

These operations implement various boolean combinations of the resultants of the overlay.

## Constructor & Destructor Documentation

geos::operation::overlay::OverlayOp::OverlayOp | ( | const geom::Geometry * | g0,
|  | const geom::Geometry * | g1 |
| ) |  |  |

Construct an OverlayOp with the given Geometry args.

Ownership of passed args will remain to caller, and the OverlayOp won't change them in any way.

## Member Function Documentation

static bool geos::operation::overlay::OverlayOp::isResultOfOp | ( | int | loc0,
|  | int | loc1,
|  | OpCode | opCode |
| ) |  |  | `[static]`

This method will handle arguments of Location.NULL correctly.

Returns:
  true if the locations correspond to the opCode

bool geos::operation::overlay::OverlayOp::isCoveredByLA | ( | const geom::Coordinate & | coord | ) |

This method is used to decide if a point node should be included in the result or not.

Returns:
  true if the coord point is covered by a result Line or Area geometry

bool geos::operation::overlay::OverlayOp::isCoveredByA | ( | const geom::Coordinate & | coord | ) |

This method is used to decide if an L edge should be included in the result or not.

Returns:
  true if the coord point is covered by a result Area geometry

void geos::operation::overlay::OverlayOp::insertUniqueEdge | ( | geomgraph::Edge * | e | ) | `[protected]`

Insert an edge from one of the noded input graphs.

Checks edges that are inserted to see if an identical edge already exists. If so, the edge is not inserted, but its label is merged with the existing edge.

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

- OverlayOp.h