GEOS  3.8.0dev
Public Member Functions | List of all members
geos::operation::buffer::OffsetSegmentGenerator Class Reference

#include <OffsetSegmentGenerator.h>

Public Member Functions

 OffsetSegmentGenerator (const geom::PrecisionModel *newPrecisionModel, const BufferParameters &bufParams, double distance)
bool hasNarrowConcaveAngle () const
void initSideSegments (const geom::Coordinate &nS1, const geom::Coordinate &nS2, int nSide)
void getCoordinates (std::vector< geom::CoordinateSequence * > &to)
 Get coordinates by taking ownership of them. More...
void closeRing ()
void createCircle (const geom::Coordinate &p, double distance)
 Adds a CW circle around a point.
void createSquare (const geom::Coordinate &p, double distance)
 Adds a CW square around a point.
void addFirstSegment ()
 Add first offset point.
void addLastSegment ()
 Add last offset point.
void addNextSegment (const geom::Coordinate &p, bool addStartPoint)
void addLineEndCap (const geom::Coordinate &p0, const geom::Coordinate &p1)
 Add an end cap around point p1, terminating a line segment coming from p0.
void addSegments (const geom::CoordinateSequence &pts, bool isForward)

Detailed Description

Generates segments which form an offset curve. Supports all end cap and join options provided for buffering. Implements various heuristics to produce smoother, simpler curves which are still within a reasonable tolerance of the true curve.

Martin Davis

Member Function Documentation

void geos::operation::buffer::OffsetSegmentGenerator::getCoordinates ( std::vector< geom::CoordinateSequence * > &  to)

Get coordinates by taking ownership of them.

After this call, the coordinates reference in this object are dropped. Calling twice will segfault...

FIXME: refactor memory management of this

bool geos::operation::buffer::OffsetSegmentGenerator::hasNarrowConcaveAngle ( ) const

Tests whether the input has a narrow concave angle (relative to the offset distance). In this case the generated offset curve will contain self-intersections and heuristic closing segments. This is expected behaviour in the case of buffer curves. For pure offset curves, the output needs to be further treated before it can be used.

true if the input has a narrow concave angle

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