C API for the GEOS geometry algorithms library. More...

#include <stddef.h>
#include <geos/export.h>

Typedefs
typedef struct GEOSContextHandle_HS *	GEOSContextHandle_t

typedef void(*	GEOSMessageHandler) (GEOS_PRINTF_FORMAT const char *fmt,...) GEOS_PRINTF_FORMAT_ATTR(1

typedef void() typedef void(	GEOSMessageHandler_r) (const char message, void userdata)

typedef struct GEOSGeom_t	GEOSGeometry

typedef struct GEOSPrepGeom_t	GEOSPreparedGeometry

typedef struct GEOSCoordSeq_t	GEOSCoordSequence

typedef struct GEOSSTRtree_t	GEOSSTRtree

typedef struct GEOSBufParams_t	GEOSBufferParams

typedef struct GEOSMakeValidParams_t	GEOSMakeValidParams

typedef void(*	GEOSQueryCallback) (void item, void userdata)

typedef int(*	GEOSDistanceCallback) (const void item1, const void item2, double distance, void userdata)

typedef int(*	GEOSTransformXYCallback) (double x, double y, void *userdata)

typedef int(*	GEOSTransformXYZCallback) (double x, double y, double z, void userdata)

typedef void()	GEOSInterruptCallback(void)

typedef struct GEOSWKTReader_t	GEOSWKTReader

typedef struct GEOSWKTWriter_t	GEOSWKTWriter

typedef struct GEOSWKBReader_t	GEOSWKBReader

typedef struct GEOSWKBWriter_t	GEOSWKBWriter

typedef struct GEOSGeoJSONReader_t	GEOSGeoJSONReader

typedef struct GEOSGeoJSONWriter_t	GEOSGeoJSONWriter

Enumerations
enum	GEOSGeomTypes { GEOS_POINT , GEOS_LINESTRING , GEOS_LINEARRING , GEOS_POLYGON , GEOS_MULTIPOINT , GEOS_MULTILINESTRING , GEOS_MULTIPOLYGON , GEOS_GEOMETRYCOLLECTION , GEOS_CIRCULARSTRING , GEOS_COMPOUNDCURVE , GEOS_CURVEPOLYGON , GEOS_MULTICURVE , GEOS_MULTISURFACE }

enum	GEOSWKBByteOrders { GEOS_WKB_XDR = 0 , GEOS_WKB_NDR = 1 }

enum	GEOSWKBFlavors { GEOS_WKB_EXTENDED = 1 , GEOS_WKB_ISO = 2 }

enum	GEOSBufCapStyles { GEOSBUF_CAP_ROUND = 1 , GEOSBUF_CAP_FLAT = 2 , GEOSBUF_CAP_SQUARE = 3 }

enum	GEOSBufJoinStyles { GEOSBUF_JOIN_ROUND = 1 , GEOSBUF_JOIN_MITRE = 2 , GEOSBUF_JOIN_BEVEL = 3 }

enum	GEOSRelateBoundaryNodeRules { GEOSRELATE_BNR_MOD2 = 1 , GEOSRELATE_BNR_OGC = 1 , GEOSRELATE_BNR_ENDPOINT = 2 , GEOSRELATE_BNR_MULTIVALENT_ENDPOINT = 3 , GEOSRELATE_BNR_MONOVALENT_ENDPOINT = 4 }

enum	GEOSValidFlags { GEOSVALID_ALLOW_SELFTOUCHING_RING_FORMING_HOLE = 1 }

enum	GEOSMakeValidMethods { GEOS_MAKE_VALID_LINEWORK = 0 , GEOS_MAKE_VALID_STRUCTURE = 1 }

enum	GEOSPrecisionRules { GEOS_PREC_VALID_OUTPUT = 0 , GEOS_PREC_NO_TOPO = 1 , GEOS_PREC_KEEP_COLLAPSED = 2 }

Functions
GEOSInterruptCallback *	GEOS_interruptRegisterCallback (GEOSInterruptCallback *cb)

void	GEOS_interruptRequest (void)

void	GEOS_interruptCancel (void)

GEOSContextHandle_t	GEOS_init_r (void)

void	GEOS_finish_r (GEOSContextHandle_t handle)

GEOSMessageHandler	GEOSContext_setNoticeHandler_r (GEOSContextHandle_t extHandle, GEOSMessageHandler nf)

GEOSMessageHandler	GEOSContext_setErrorHandler_r (GEOSContextHandle_t extHandle, GEOSMessageHandler ef)

GEOSMessageHandler_r	GEOSContext_setNoticeMessageHandler_r (GEOSContextHandle_t extHandle, GEOSMessageHandler_r nf, void *userData)

GEOSMessageHandler_r	GEOSContext_setErrorMessageHandler_r (GEOSContextHandle_t extHandle, GEOSMessageHandler_r ef, void *userData)

GEOSCoordSequence *	GEOSCoordSeq_create_r (GEOSContextHandle_t handle, unsigned int size, unsigned int dims)

GEOSCoordSequence *	GEOSCoordSeq_copyFromBuffer_r (GEOSContextHandle_t handle, const double *buf, unsigned int size, int hasZ, int hasM)

GEOSCoordSequence *	GEOSCoordSeq_copyFromArrays_r (GEOSContextHandle_t handle, const double x, const double y, const double z, const double m, unsigned int size)

int	GEOSCoordSeq_copyToBuffer_r (GEOSContextHandle_t handle, const GEOSCoordSequence s, double buf, int hasZ, int hasM)

int	GEOSCoordSeq_copyToArrays_r (GEOSContextHandle_t handle, const GEOSCoordSequence s, double x, double y, double z, double *m)

GEOSCoordSequence *	GEOSCoordSeq_clone_r (GEOSContextHandle_t handle, const GEOSCoordSequence *s)

void	GEOSCoordSeq_destroy_r (GEOSContextHandle_t handle, GEOSCoordSequence *s)

int	GEOSCoordSeq_setX_r (GEOSContextHandle_t handle, GEOSCoordSequence *s, unsigned int idx, double val)

int	GEOSCoordSeq_setY_r (GEOSContextHandle_t handle, GEOSCoordSequence *s, unsigned int idx, double val)

int	GEOSCoordSeq_setZ_r (GEOSContextHandle_t handle, GEOSCoordSequence *s, unsigned int idx, double val)

int	GEOSCoordSeq_setXY_r (GEOSContextHandle_t handle, GEOSCoordSequence *s, unsigned int idx, double x, double y)

int	GEOSCoordSeq_setXYZ_r (GEOSContextHandle_t handle, GEOSCoordSequence *s, unsigned int idx, double x, double y, double z)

int	GEOSCoordSeq_setOrdinate_r (GEOSContextHandle_t handle, GEOSCoordSequence *s, unsigned int idx, unsigned int dim, double val)

int	GEOSCoordSeq_getX_r (GEOSContextHandle_t handle, const GEOSCoordSequence s, unsigned int idx, double val)

int	GEOSCoordSeq_getY_r (GEOSContextHandle_t handle, const GEOSCoordSequence s, unsigned int idx, double val)

int	GEOSCoordSeq_getZ_r (GEOSContextHandle_t handle, const GEOSCoordSequence s, unsigned int idx, double val)

int	GEOSCoordSeq_getXY_r (GEOSContextHandle_t handle, const GEOSCoordSequence s, unsigned int idx, double x, double *y)

int	GEOSCoordSeq_getXYZ_r (GEOSContextHandle_t handle, const GEOSCoordSequence s, unsigned int idx, double x, double y, double z)

int	GEOSCoordSeq_getOrdinate_r (GEOSContextHandle_t handle, const GEOSCoordSequence s, unsigned int idx, unsigned int dim, double val)

int	GEOSCoordSeq_getSize_r (GEOSContextHandle_t handle, const GEOSCoordSequence s, unsigned int size)

int	GEOSCoordSeq_getDimensions_r (GEOSContextHandle_t handle, const GEOSCoordSequence s, unsigned int dims)

int	GEOSCoordSeq_isCCW_r (GEOSContextHandle_t handle, const GEOSCoordSequence s, char is_ccw)

double	GEOSProject_r (GEOSContextHandle_t handle, const GEOSGeometry line, const GEOSGeometry point)

GEOSGeometry *	GEOSInterpolate_r (GEOSContextHandle_t handle, const GEOSGeometry *line, double d)

double	GEOSProjectNormalized_r (GEOSContextHandle_t handle, const GEOSGeometry g, const GEOSGeometry p)

GEOSGeometry *	GEOSInterpolateNormalized_r (GEOSContextHandle_t handle, const GEOSGeometry *g, double d)

GEOSGeometry *	GEOSBuffer_r (GEOSContextHandle_t handle, const GEOSGeometry *g, double width, int quadsegs)

GEOSBufferParams *	GEOSBufferParams_create_r (GEOSContextHandle_t handle)

void	GEOSBufferParams_destroy_r (GEOSContextHandle_t handle, GEOSBufferParams *parms)

int	GEOSBufferParams_setEndCapStyle_r (GEOSContextHandle_t handle, GEOSBufferParams *p, int style)

int	GEOSBufferParams_setJoinStyle_r (GEOSContextHandle_t handle, GEOSBufferParams *p, int joinStyle)

int	GEOSBufferParams_setMitreLimit_r (GEOSContextHandle_t handle, GEOSBufferParams *p, double mitreLimit)

int	GEOSBufferParams_setQuadrantSegments_r (GEOSContextHandle_t handle, GEOSBufferParams *p, int quadSegs)

int	GEOSBufferParams_setSingleSided_r (GEOSContextHandle_t handle, GEOSBufferParams *p, int singleSided)

GEOSGeometry *	GEOSBufferWithParams_r (GEOSContextHandle_t handle, const GEOSGeometry g, const GEOSBufferParams p, double width)

GEOSGeometry *	GEOSBufferWithStyle_r (GEOSContextHandle_t handle, const GEOSGeometry *g, double width, int quadsegs, int endCapStyle, int joinStyle, double mitreLimit)

GEOSGeometry *	GEOSDensify_r (GEOSContextHandle_t handle, const GEOSGeometry *g, double tolerance)

GEOSGeometry *	GEOSOffsetCurve_r (GEOSContextHandle_t handle, const GEOSGeometry *g, double width, int quadsegs, int joinStyle, double mitreLimit)

GEOSGeometry *	GEOSGeom_createPoint_r (GEOSContextHandle_t handle, GEOSCoordSequence *s)

GEOSGeometry *	GEOSGeom_createPointFromXY_r (GEOSContextHandle_t handle, double x, double y)

GEOSGeometry *	GEOSGeom_createEmptyPoint_r (GEOSContextHandle_t handle)

GEOSGeometry *	GEOSGeom_createLinearRing_r (GEOSContextHandle_t handle, GEOSCoordSequence *s)

GEOSGeometry *	GEOSGeom_createLineString_r (GEOSContextHandle_t handle, GEOSCoordSequence *s)

GEOSGeometry *	GEOSGeom_createEmptyLineString_r (GEOSContextHandle_t handle)

GEOSGeometry *	GEOSGeom_createEmptyPolygon_r (GEOSContextHandle_t handle)

GEOSGeometry *	GEOSGeom_createPolygon_r (GEOSContextHandle_t handle, GEOSGeometry shell, GEOSGeometry *holes, unsigned int nholes)

GEOSGeometry *	GEOSGeom_createCollection_r (GEOSContextHandle_t handle, int type, GEOSGeometry **geoms, unsigned int ngeoms)

GEOSGeometry **	GEOSGeom_releaseCollection_r (GEOSContextHandle_t handle, GEOSGeometry collection, unsigned int ngeoms)

GEOSGeometry *	GEOSGeom_createEmptyCollection_r (GEOSContextHandle_t handle, int type)

GEOSGeometry *	GEOSGeom_createRectangle_r (GEOSContextHandle_t handle, double xmin, double ymin, double xmax, double ymax)

GEOSGeometry *	GEOSGeom_clone_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

GEOSGeometry *	GEOSGeom_createCircularString_r (GEOSContextHandle_t handle, GEOSCoordSequence *s)

GEOSGeometry *	GEOSGeom_createEmptyCircularString_r (GEOSContextHandle_t handle)

GEOSGeometry *	GEOSGeom_createCompoundCurve_r (GEOSContextHandle_t handle, GEOSGeometry **curves, unsigned int ncurves)

GEOSGeometry *	GEOSGeom_createEmptyCompoundCurve_r (GEOSContextHandle_t handle)

GEOSGeometry *	GEOSGeom_createCurvePolygon_r (GEOSContextHandle_t handle, GEOSGeometry shell, GEOSGeometry *holes, unsigned int nholes)

GEOSGeometry *	GEOSGeom_createEmptyCurvePolygon_r (GEOSContextHandle_t handle)

void	GEOSGeom_destroy_r (GEOSContextHandle_t handle, GEOSGeometry *g)

GEOSGeometry *	GEOSCoverageUnion_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

int	GEOSCoverageIsValid_r (GEOSContextHandle_t extHandle, const GEOSGeometry input, double gapWidth, GEOSGeometry *output)

GEOSGeometry *	GEOSCoverageSimplifyVW_r (GEOSContextHandle_t extHandle, const GEOSGeometry *input, double tolerance, int preserveBoundary)

GEOSGeometry *	GEOSEnvelope_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

GEOSGeometry *	GEOSIntersection_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2)

GEOSGeometry *	GEOSIntersectionPrec_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2, double gridSize)

GEOSGeometry *	GEOSConvexHull_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

GEOSGeometry *	GEOSConcaveHull_r (GEOSContextHandle_t handle, const GEOSGeometry *g, double ratio, unsigned int allowHoles)

GEOSGeometry *	GEOSConcaveHullByLength_r (GEOSContextHandle_t handle, const GEOSGeometry *g, double ratio, unsigned int allowHoles)

GEOSGeometry *	GEOSPolygonHullSimplify_r (GEOSContextHandle_t handle, const GEOSGeometry *g, unsigned int isOuter, double vertexNumFraction)

GEOSGeometry *	GEOSPolygonHullSimplifyMode_r (GEOSContextHandle_t handle, const GEOSGeometry *g, unsigned int isOuter, unsigned int parameterMode, double parameter)

GEOSGeometry *	GEOSConcaveHullOfPolygons_r (GEOSContextHandle_t handle, const GEOSGeometry *g, double lengthRatio, unsigned int isTight, unsigned int isHolesAllowed)

GEOSGeometry *	GEOSMinimumRotatedRectangle_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

GEOSGeometry *	GEOSMaximumInscribedCircle_r (GEOSContextHandle_t handle, const GEOSGeometry *g, double tolerance)

GEOSGeometry *	GEOSLargestEmptyCircle_r (GEOSContextHandle_t handle, const GEOSGeometry g, const GEOSGeometry boundary, double tolerance)

GEOSGeometry *	GEOSMinimumWidth_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

GEOSGeometry *	GEOSMinimumClearanceLine_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

int	GEOSMinimumClearance_r (GEOSContextHandle_t handle, const GEOSGeometry g, double distance)

GEOSGeometry *	GEOSDifference_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2)

GEOSGeometry *	GEOSDifferencePrec_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2, double gridSize)

GEOSGeometry *	GEOSSymDifference_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2)

GEOSGeometry *	GEOSSymDifferencePrec_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2, double gridSize)

GEOSGeometry *	GEOSBoundary_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

GEOSGeometry *	GEOSUnion_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2)

GEOSGeometry *	GEOSUnionPrec_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2, double gridSize)

GEOSGeometry *	GEOSUnaryUnion_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

GEOSGeometry *	GEOSUnaryUnionPrec_r (GEOSContextHandle_t handle, const GEOSGeometry *g, double gridSize)

GEOSGeometry *	GEOSDisjointSubsetUnion_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

GEOSGeometry *	GEOSPointOnSurface_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

GEOSGeometry *	GEOSGetCentroid_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

GEOSGeometry *	GEOSMinimumBoundingCircle_r (GEOSContextHandle_t handle, const GEOSGeometry g, double radius, GEOSGeometry **center)

GEOSGeometry *	GEOSNode_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

GEOSGeometry *	GEOSClipByRect_r (GEOSContextHandle_t handle, const GEOSGeometry *g, double xmin, double ymin, double xmax, double ymax)

GEOSGeometry *	GEOSPolygonize_r (GEOSContextHandle_t handle, const GEOSGeometry *const geoms[], unsigned int ngeoms)

GEOSGeometry *	GEOSPolygonize_valid_r (GEOSContextHandle_t handle, const GEOSGeometry *const geoms[], unsigned int ngems)

GEOSGeometry *	GEOSPolygonizer_getCutEdges_r (GEOSContextHandle_t handle, const GEOSGeometry *const geoms[], unsigned int ngeoms)

GEOSGeometry *	GEOSPolygonize_full_r (GEOSContextHandle_t handle, const GEOSGeometry input, GEOSGeometry cuts, GEOSGeometry dangles, GEOSGeometry *invalidRings)

GEOSGeometry *	GEOSBuildArea_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

GEOSGeometry *	GEOSLineMerge_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

GEOSGeometry *	GEOSLineMergeDirected_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

GEOSGeometry *	GEOSLineSubstring_r (GEOSContextHandle_t handle, const GEOSGeometry *g, double start_fraction, double end_fdraction)

GEOSGeometry *	GEOSReverse_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

GEOSGeometry *	GEOSSimplify_r (GEOSContextHandle_t handle, const GEOSGeometry *g, double tolerance)

GEOSGeometry *	GEOSTopologyPreserveSimplify_r (GEOSContextHandle_t handle, const GEOSGeometry *g, double tolerance)

GEOSGeometry *	GEOSGeom_extractUniquePoints_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

GEOSGeometry *	GEOSSharedPaths_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2)

GEOSGeometry *	GEOSSnap_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2, double tolerance)

GEOSGeometry *	GEOSDelaunayTriangulation_r (GEOSContextHandle_t handle, const GEOSGeometry *g, double tolerance, int onlyEdges)

GEOSGeometry *	GEOSConstrainedDelaunayTriangulation_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

GEOSGeometry *	GEOSVoronoiDiagram_r (GEOSContextHandle_t extHandle, const GEOSGeometry g, const GEOSGeometry env, double tolerance, int flags)

int	GEOSSegmentIntersection_r (GEOSContextHandle_t extHandle, double ax0, double ay0, double ax1, double ay1, double bx0, double by0, double bx1, double by1, double cx, double cy)

char	GEOSDisjoint_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSTouches_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSIntersects_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSCrosses_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSWithin_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSContains_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSOverlaps_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSEquals_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSEqualsExact_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2, double tolerance)

char	GEOSEqualsIdentical_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSCovers_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSCoveredBy_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2)

const GEOSPreparedGeometry *	GEOSPrepare_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

void	GEOSPreparedGeom_destroy_r (GEOSContextHandle_t handle, const GEOSPreparedGeometry *g)

char	GEOSPreparedContains_r (GEOSContextHandle_t handle, const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedContainsXY_r (GEOSContextHandle_t handle, const GEOSPreparedGeometry *pg1, double x, double y)

char	GEOSPreparedContainsProperly_r (GEOSContextHandle_t handle, const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedCoveredBy_r (GEOSContextHandle_t handle, const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedCovers_r (GEOSContextHandle_t handle, const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedCrosses_r (GEOSContextHandle_t handle, const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedDisjoint_r (GEOSContextHandle_t handle, const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedIntersects_r (GEOSContextHandle_t handle, const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedIntersectsXY_r (GEOSContextHandle_t handle, const GEOSPreparedGeometry *pg1, double x, double y)

char	GEOSPreparedOverlaps_r (GEOSContextHandle_t handle, const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedTouches_r (GEOSContextHandle_t handle, const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedWithin_r (GEOSContextHandle_t handle, const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char *	GEOSPreparedRelate_r (GEOSContextHandle_t handle, const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedRelatePattern_r (GEOSContextHandle_t handle, const GEOSPreparedGeometry pg1, const GEOSGeometry g2, const char *im)

GEOSCoordSequence *	GEOSPreparedNearestPoints_r (GEOSContextHandle_t handle, const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

int	GEOSPreparedDistance_r (GEOSContextHandle_t handle, const GEOSPreparedGeometry pg1, const GEOSGeometry g2, double *dist)

char	GEOSPreparedDistanceWithin_r (GEOSContextHandle_t handle, const GEOSPreparedGeometry pg1, const GEOSGeometry g2, double dist)

GEOSSTRtree *	GEOSSTRtree_create_r (GEOSContextHandle_t handle, size_t nodeCapacity)

int	GEOSSTRtree_build_r (GEOSContextHandle_t handle, GEOSSTRtree *tree)

void	GEOSSTRtree_insert_r (GEOSContextHandle_t handle, GEOSSTRtree tree, const GEOSGeometry g, void *item)

void	GEOSSTRtree_query_r (GEOSContextHandle_t handle, GEOSSTRtree tree, const GEOSGeometry g, GEOSQueryCallback callback, void *userdata)

const GEOSGeometry *	GEOSSTRtree_nearest_r (GEOSContextHandle_t handle, GEOSSTRtree tree, const GEOSGeometry geom)

const void *	GEOSSTRtree_nearest_generic_r (GEOSContextHandle_t handle, GEOSSTRtree tree, const void item, const GEOSGeometry itemEnvelope, GEOSDistanceCallback distancefn, void userdata)

void	GEOSSTRtree_iterate_r (GEOSContextHandle_t handle, GEOSSTRtree tree, GEOSQueryCallback callback, void userdata)

char	GEOSSTRtree_remove_r (GEOSContextHandle_t handle, GEOSSTRtree tree, const GEOSGeometry g, void *item)

void	GEOSSTRtree_destroy_r (GEOSContextHandle_t handle, GEOSSTRtree *tree)

char	GEOSisEmpty_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

char	GEOSisSimple_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

char	GEOSisRing_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

char	GEOSHasZ_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

char	GEOSHasM_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

char	GEOSisClosed_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

char	GEOSRelatePattern_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2, const char *imPattern)

char *	GEOSRelate_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSRelatePatternMatch_r (GEOSContextHandle_t handle, const char intMatrix, const char imPattern)

char *	GEOSRelateBoundaryNodeRule_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2, int bnr)

char	GEOSisValid_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

char *	GEOSisValidReason_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

char	GEOSisValidDetail_r (GEOSContextHandle_t handle, const GEOSGeometry g, int flags, char reason, GEOSGeometry *location)

GEOSMakeValidParams *	GEOSMakeValidParams_create_r (GEOSContextHandle_t extHandle)

void	GEOSMakeValidParams_destroy_r (GEOSContextHandle_t handle, GEOSMakeValidParams *parms)

int	GEOSMakeValidParams_setKeepCollapsed_r (GEOSContextHandle_t handle, GEOSMakeValidParams *p, int style)

int	GEOSMakeValidParams_setMethod_r (GEOSContextHandle_t handle, GEOSMakeValidParams *p, enum GEOSMakeValidMethods method)

GEOSGeometry *	GEOSMakeValid_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

GEOSGeometry *	GEOSMakeValidWithParams_r (GEOSContextHandle_t handle, const GEOSGeometry g, const GEOSMakeValidParams makeValidParams)

GEOSGeometry *	GEOSRemoveRepeatedPoints_r (GEOSContextHandle_t handle, const GEOSGeometry *g, double tolerance)

char *	GEOSGeomType_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

int	GEOSGeomTypeId_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

int	GEOSGetSRID_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

void	GEOSSetSRID_r (GEOSContextHandle_t handle, GEOSGeometry *g, int SRID)

void *	GEOSGeom_getUserData_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

void	GEOSGeom_setUserData_r (GEOSContextHandle_t handle, GEOSGeometry g, void userData)

int	GEOSGetNumGeometries_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

const GEOSGeometry *	GEOSGetGeometryN_r (GEOSContextHandle_t handle, const GEOSGeometry *g, int n)

int	GEOSNormalize_r (GEOSContextHandle_t handle, GEOSGeometry *g)

int	GEOSOrientPolygons_r (GEOSContextHandle_t handle, GEOSGeometry *g, int exteriorCW)

GEOSGeometry *	GEOSGeom_setPrecision_r (GEOSContextHandle_t handle, const GEOSGeometry *g, double gridSize, int flags)

double	GEOSGeom_getPrecision_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

int	GEOSGetNumInteriorRings_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

int	GEOSGeomGetNumPoints_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

int	GEOSGeomGetX_r (GEOSContextHandle_t handle, const GEOSGeometry g, double x)

int	GEOSGeomGetY_r (GEOSContextHandle_t handle, const GEOSGeometry g, double y)

int	GEOSGeomGetZ_r (GEOSContextHandle_t handle, const GEOSGeometry g, double z)

int	GEOSGeomGetM_r (GEOSContextHandle_t handle, const GEOSGeometry g, double m)

const GEOSGeometry *	GEOSGetInteriorRingN_r (GEOSContextHandle_t handle, const GEOSGeometry *g, int n)

const GEOSGeometry *	GEOSGetExteriorRing_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

int	GEOSGetNumCoordinates_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

const GEOSCoordSequence *	GEOSGeom_getCoordSeq_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

int	GEOSGeom_getDimensions_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

int	GEOSGeom_getCoordinateDimension_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

int	GEOSGeom_getXMin_r (GEOSContextHandle_t handle, const GEOSGeometry g, double value)

int	GEOSGeom_getYMin_r (GEOSContextHandle_t handle, const GEOSGeometry g, double value)

int	GEOSGeom_getXMax_r (GEOSContextHandle_t handle, const GEOSGeometry g, double value)

int	GEOSGeom_getYMax_r (GEOSContextHandle_t handle, const GEOSGeometry g, double value)

int	GEOSGeom_getExtent_r (GEOSContextHandle_t handle, const GEOSGeometry g, double xmin, double ymin, double xmax, double *ymax)

GEOSGeometry *	GEOSGeomGetPointN_r (GEOSContextHandle_t handle, const GEOSGeometry *g, int n)

GEOSGeometry *	GEOSGeomGetStartPoint_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

GEOSGeometry *	GEOSGeomGetEndPoint_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

int	GEOSArea_r (GEOSContextHandle_t handle, const GEOSGeometry g, double area)

int	GEOSLength_r (GEOSContextHandle_t handle, const GEOSGeometry g, double length)

int	GEOSDistance_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2, double *dist)

char	GEOSDistanceWithin_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2, double dist)

int	GEOSDistanceIndexed_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2, double *dist)

int	GEOSHausdorffDistance_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2, double *dist)

int	GEOSHausdorffDistanceDensify_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2, double densifyFrac, double *dist)

int	GEOSFrechetDistance_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2, double *dist)

int	GEOSFrechetDistanceDensify_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2, double densifyFrac, double *dist)

int	GEOSHilbertCode_r (GEOSContextHandle_t handle, const GEOSGeometry geom, const GEOSGeometry extent, unsigned int level, unsigned int *code)

int	GEOSGeomGetLength_r (GEOSContextHandle_t handle, const GEOSGeometry g, double length)

GEOSCoordSequence *	GEOSNearestPoints_r (GEOSContextHandle_t handle, const GEOSGeometry g1, const GEOSGeometry g2)

GEOSGeometry *	GEOSGeom_transformXY_r (GEOSContextHandle_t handle, const GEOSGeometry g, GEOSTransformXYCallback callback, void userdata)

GEOSGeometry *	GEOSGeom_transformXYZ_r (GEOSContextHandle_t handle, const GEOSGeometry g, GEOSTransformXYZCallback callback, void userdata)

int	GEOSOrientationIndex_r (GEOSContextHandle_t handle, double Ax, double Ay, double Bx, double By, double Px, double Py)

GEOSWKTReader *	GEOSWKTReader_create_r (GEOSContextHandle_t handle)

void	GEOSWKTReader_destroy_r (GEOSContextHandle_t handle, GEOSWKTReader *reader)

GEOSGeometry *	GEOSWKTReader_read_r (GEOSContextHandle_t handle, GEOSWKTReader reader, const char wkt)

void	GEOSWKTReader_setFixStructure_r (GEOSContextHandle_t handle, GEOSWKTReader *reader, char doFix)

GEOSWKTWriter *	GEOSWKTWriter_create_r (GEOSContextHandle_t handle)

void	GEOSWKTWriter_destroy_r (GEOSContextHandle_t handle, GEOSWKTWriter *writer)

char *	GEOSWKTWriter_write_r (GEOSContextHandle_t handle, GEOSWKTWriter writer, const GEOSGeometry g)

void	GEOSWKTWriter_setTrim_r (GEOSContextHandle_t handle, GEOSWKTWriter *writer, char trim)

void	GEOSWKTWriter_setRoundingPrecision_r (GEOSContextHandle_t handle, GEOSWKTWriter *writer, int precision)

void	GEOSWKTWriter_setOutputDimension_r (GEOSContextHandle_t handle, GEOSWKTWriter *writer, int dim)

int	GEOSWKTWriter_getOutputDimension_r (GEOSContextHandle_t handle, GEOSWKTWriter *writer)

void	GEOSWKTWriter_setOld3D_r (GEOSContextHandle_t handle, GEOSWKTWriter *writer, int useOld3D)

int	GEOS_printDouble (double d, unsigned int precision, char *result)

GEOSWKBReader *	GEOSWKBReader_create_r (GEOSContextHandle_t handle)

void	GEOSWKBReader_destroy_r (GEOSContextHandle_t handle, GEOSWKBReader *reader)

void	GEOSWKBReader_setFixStructure_r (GEOSContextHandle_t handle, GEOSWKBReader *reader, char doFix)

GEOSGeometry *	GEOSWKBReader_read_r (GEOSContextHandle_t handle, GEOSWKBReader reader, const unsigned char wkb, size_t size)

GEOSGeometry *	GEOSWKBReader_readHEX_r (GEOSContextHandle_t handle, GEOSWKBReader reader, const unsigned char hex, size_t size)

GEOSWKBWriter *	GEOSWKBWriter_create_r (GEOSContextHandle_t handle)

void	GEOSWKBWriter_destroy_r (GEOSContextHandle_t handle, GEOSWKBWriter *writer)

unsigned char *	GEOSWKBWriter_write_r (GEOSContextHandle_t handle, GEOSWKBWriter writer, const GEOSGeometry g, size_t *size)

unsigned char *	GEOSWKBWriter_writeHEX_r (GEOSContextHandle_t handle, GEOSWKBWriter writer, const GEOSGeometry g, size_t *size)

int	GEOSWKBWriter_getOutputDimension_r (GEOSContextHandle_t handle, const GEOSWKBWriter *writer)

void	GEOSWKBWriter_setOutputDimension_r (GEOSContextHandle_t handle, GEOSWKBWriter *writer, int newDimension)

int	GEOSWKBWriter_getByteOrder_r (GEOSContextHandle_t handle, const GEOSWKBWriter *writer)

void	GEOSWKBWriter_setByteOrder_r (GEOSContextHandle_t handle, GEOSWKBWriter *writer, int byteOrder)

int	GEOSWKBWriter_getFlavor_r (GEOSContextHandle_t handle, const GEOSWKBWriter *writer)

void	GEOSWKBWriter_setFlavor_r (GEOSContextHandle_t handle, GEOSWKBWriter *writer, int flavor)

char	GEOSWKBWriter_getIncludeSRID_r (GEOSContextHandle_t handle, const GEOSWKBWriter *writer)

void	GEOSWKBWriter_setIncludeSRID_r (GEOSContextHandle_t handle, GEOSWKBWriter *writer, const char writeSRID)

GEOSGeoJSONReader *	GEOSGeoJSONReader_create_r (GEOSContextHandle_t handle)

void	GEOSGeoJSONReader_destroy_r (GEOSContextHandle_t handle, GEOSGeoJSONReader *reader)

GEOSGeometry *	GEOSGeoJSONReader_readGeometry_r (GEOSContextHandle_t handle, GEOSGeoJSONReader reader, const char geojson)

GEOSGeoJSONWriter *	GEOSGeoJSONWriter_create_r (GEOSContextHandle_t handle)

void	GEOSGeoJSONWriter_destroy_r (GEOSContextHandle_t handle, GEOSGeoJSONWriter *writer)

char *	GEOSGeoJSONWriter_writeGeometry_r (GEOSContextHandle_t handle, GEOSGeoJSONWriter writer, const GEOSGeometry g, int indent)

void	GEOSFree_r (GEOSContextHandle_t handle, void *buffer)

const char *	GEOSversion (void)

Library and Memory Management
Functions to initialize and tear down the library, and deallocate memory.
void	initGEOS (GEOSMessageHandler notice_function, GEOSMessageHandler error_function)

void	finishGEOS (void)

void	GEOSFree (void *buffer)

Coordinate Sequences
A GEOSCoordSequence is an ordered list of coordinates. Coordinates are 2 (XY), 3 (XYZ or XYM), or 4 (XYZM) dimensional.
GEOSCoordSequence *	GEOSCoordSeq_create (unsigned int size, unsigned int dims)

GEOSCoordSequence *	GEOSCoordSeq_copyFromBuffer (const double *buf, unsigned int size, int hasZ, int hasM)

GEOSCoordSequence *	GEOSCoordSeq_copyFromArrays (const double x, const double y, const double z, const double m, unsigned int size)

int	GEOSCoordSeq_copyToBuffer (const GEOSCoordSequence s, double buf, int hasZ, int hasM)

int	GEOSCoordSeq_copyToArrays (const GEOSCoordSequence s, double x, double y, double z, double *m)

GEOSCoordSequence *	GEOSCoordSeq_clone (const GEOSCoordSequence *s)

void	GEOSCoordSeq_destroy (GEOSCoordSequence *s)

int	GEOSCoordSeq_setX (GEOSCoordSequence *s, unsigned int idx, double val)

int	GEOSCoordSeq_setY (GEOSCoordSequence *s, unsigned int idx, double val)

int	GEOSCoordSeq_setZ (GEOSCoordSequence *s, unsigned int idx, double val)

int	GEOSCoordSeq_setXY (GEOSCoordSequence *s, unsigned int idx, double x, double y)

int	GEOSCoordSeq_setXYZ (GEOSCoordSequence *s, unsigned int idx, double x, double y, double z)

int	GEOSCoordSeq_setOrdinate (GEOSCoordSequence *s, unsigned int idx, unsigned int dim, double val)

int	GEOSCoordSeq_getX (const GEOSCoordSequence s, unsigned int idx, double val)

int	GEOSCoordSeq_getY (const GEOSCoordSequence s, unsigned int idx, double val)

int	GEOSCoordSeq_getZ (const GEOSCoordSequence s, unsigned int idx, double val)

int	GEOSCoordSeq_getXY (const GEOSCoordSequence s, unsigned int idx, double x, double *y)

int	GEOSCoordSeq_getXYZ (const GEOSCoordSequence s, unsigned int idx, double x, double y, double z)

int	GEOSCoordSeq_getOrdinate (const GEOSCoordSequence s, unsigned int idx, unsigned int dim, double val)

int	GEOSCoordSeq_getSize (const GEOSCoordSequence s, unsigned int size)

int	GEOSCoordSeq_getDimensions (const GEOSCoordSequence s, unsigned int dims)

int	GEOSCoordSeq_isCCW (const GEOSCoordSequence s, char is_ccw)

Geometry Constructors
Functions for creating and destroying geometries. Created geometries must be freed with GEOSGeom_destroy().
GEOSGeometry *	GEOSGeom_createPoint (GEOSCoordSequence *s)

GEOSGeometry *	GEOSGeom_createPointFromXY (double x, double y)

GEOSGeometry *	GEOSGeom_createEmptyPoint (void)

GEOSGeometry *	GEOSGeom_createLinearRing (GEOSCoordSequence *s)

GEOSGeometry *	GEOSGeom_createLineString (GEOSCoordSequence *s)

GEOSGeometry *	GEOSGeom_createEmptyLineString (void)

GEOSGeometry *	GEOSGeom_createEmptyPolygon (void)

GEOSGeometry *	GEOSGeom_createPolygon (GEOSGeometry shell, GEOSGeometry *holes, unsigned int nholes)

GEOSGeometry *	GEOSGeom_createCircularString (GEOSCoordSequence *s)

GEOSGeometry *	GEOSGeom_createEmptyCircularString ()

GEOSGeometry *	GEOSGeom_createCompoundCurve (GEOSGeometry **curves, unsigned int ncurves)

GEOSGeometry *	GEOSGeom_createEmptyCompoundCurve ()

GEOSGeometry *	GEOSGeom_createCurvePolygon (GEOSGeometry shell, GEOSGeometry *holes, unsigned int nholes)

GEOSGeometry *	GEOSGeom_createEmptyCurvePolygon ()

GEOSGeometry *	GEOSGeom_createCollection (int type, GEOSGeometry **geoms, unsigned int ngeoms)

GEOSGeometry **	GEOSGeom_releaseCollection (GEOSGeometry collection, unsigned int ngeoms)

GEOSGeometry *	GEOSGeom_createEmptyCollection (int type)

GEOSGeometry *	GEOSGeom_createRectangle (double xmin, double ymin, double xmax, double ymax)

GEOSGeometry *	GEOSGeom_clone (const GEOSGeometry *g)

void	GEOSGeom_destroy (GEOSGeometry *g)

Geometry Accessors
Functions to provide information about geometries.
char *	GEOSGeomType (const GEOSGeometry *g)

int	GEOSGeomTypeId (const GEOSGeometry *g)

int	GEOSGetSRID (const GEOSGeometry *g)

void *	GEOSGeom_getUserData (const GEOSGeometry *g)

int	GEOSGetNumGeometries (const GEOSGeometry *g)

const GEOSGeometry *	GEOSGetGeometryN (const GEOSGeometry *g, int n)

double	GEOSGeom_getPrecision (const GEOSGeometry *g)

int	GEOSGetNumInteriorRings (const GEOSGeometry *g)

int	GEOSGeomGetNumPoints (const GEOSGeometry *g)

int	GEOSGeomGetX (const GEOSGeometry g, double x)

int	GEOSGeomGetY (const GEOSGeometry g, double y)

int	GEOSGeomGetZ (const GEOSGeometry g, double z)

int	GEOSGeomGetM (const GEOSGeometry g, double m)

const GEOSGeometry *	GEOSGetInteriorRingN (const GEOSGeometry *g, int n)

const GEOSGeometry *	GEOSGetExteriorRing (const GEOSGeometry *g)

int	GEOSGetNumCoordinates (const GEOSGeometry *g)

const GEOSCoordSequence *	GEOSGeom_getCoordSeq (const GEOSGeometry *g)

int	GEOSGeom_getDimensions (const GEOSGeometry *g)

int	GEOSGeom_getCoordinateDimension (const GEOSGeometry *g)

int	GEOSGeom_getXMin (const GEOSGeometry g, double value)

int	GEOSGeom_getYMin (const GEOSGeometry g, double value)

int	GEOSGeom_getXMax (const GEOSGeometry g, double value)

int	GEOSGeom_getYMax (const GEOSGeometry g, double value)

int	GEOSGeom_getExtent (const GEOSGeometry g, double xmin, double ymin, double xmax, double *ymax)

GEOSGeometry *	GEOSGeomGetPointN (const GEOSGeometry *g, int n)

GEOSGeometry *	GEOSGeomGetStartPoint (const GEOSGeometry *g)

GEOSGeometry *	GEOSGeomGetEndPoint (const GEOSGeometry *g)

char	GEOSisEmpty (const GEOSGeometry *g)

char	GEOSisRing (const GEOSGeometry *g)

char	GEOSHasZ (const GEOSGeometry *g)

char	GEOSHasM (const GEOSGeometry *g)

char	GEOSisClosed (const GEOSGeometry *g)

Geometry Mutators
Functions to change geometry information or content.
void	GEOSSetSRID (GEOSGeometry *g, int SRID)

void	GEOSGeom_setUserData (GEOSGeometry g, void userData)

int	GEOSNormalize (GEOSGeometry *g)

int	GEOSOrientPolygons (GEOSGeometry *g, int exteriorCW)

Validation
Functions to check and create topological validity, simplicity and geometric quality.
char	GEOSisSimple (const GEOSGeometry *g)

char	GEOSisValid (const GEOSGeometry *g)

char *	GEOSisValidReason (const GEOSGeometry *g)

char	GEOSisValidDetail (const GEOSGeometry g, int flags, char reason, GEOSGeometry *location)

GEOSGeometry *	GEOSMakeValid (const GEOSGeometry *g)

GEOSGeometry *	GEOSMakeValidWithParams (const GEOSGeometry g, const GEOSMakeValidParams makeValidParams)

GEOSMakeValidParams *	GEOSMakeValidParams_create (void)

void	GEOSMakeValidParams_destroy (GEOSMakeValidParams *parms)

int	GEOSMakeValidParams_setMethod (GEOSMakeValidParams *p, enum GEOSMakeValidMethods method)

int	GEOSMakeValidParams_setKeepCollapsed (GEOSMakeValidParams *p, int keepCollapsed)

int	GEOSMinimumClearance (const GEOSGeometry g, double d)

GEOSGeometry *	GEOSMinimumClearanceLine (const GEOSGeometry *g)

GEOSGeometry *	GEOSRemoveRepeatedPoints (const GEOSGeometry *g, double tolerance)

Geometry Metrics
Functions to compute geometry metrics.
int	GEOSArea (const GEOSGeometry g, double area)

int	GEOSLength (const GEOSGeometry g, double length)

int	GEOSGeomGetLength (const GEOSGeometry g, double length)

Distance
Functions to compute distances between geometries using various distance metrics.
int	GEOSDistance (const GEOSGeometry g1, const GEOSGeometry g2, double *dist)

char	GEOSDistanceWithin (const GEOSGeometry g1, const GEOSGeometry g2, double dist)

int	GEOSDistanceIndexed (const GEOSGeometry g1, const GEOSGeometry g2, double *dist)

GEOSCoordSequence *	GEOSNearestPoints (const GEOSGeometry g1, const GEOSGeometry g2)

int	GEOSHausdorffDistance (const GEOSGeometry g1, const GEOSGeometry g2, double *dist)

int	GEOSHausdorffDistanceDensify (const GEOSGeometry g1, const GEOSGeometry g2, double densifyFrac, double *dist)

int	GEOSFrechetDistance (const GEOSGeometry g1, const GEOSGeometry g2, double *dist)

int	GEOSFrechetDistanceDensify (const GEOSGeometry g1, const GEOSGeometry g2, double densifyFrac, double *dist)

Linear Referencing
Functions to operate on LineStrings using locations specified by distance along the line.
double	GEOSProject (const GEOSGeometry line, const GEOSGeometry point)

GEOSGeometry *	GEOSInterpolate (const GEOSGeometry *line, double d)

double	GEOSProjectNormalized (const GEOSGeometry line, const GEOSGeometry point)

GEOSGeometry *	GEOSInterpolateNormalized (const GEOSGeometry *line, double proportion)

Overlay
Functions for computing boolean set-theoretic values from overlay pairs of geometries.
GEOSGeometry *	GEOSIntersection (const GEOSGeometry g1, const GEOSGeometry g2)

GEOSGeometry *	GEOSIntersectionPrec (const GEOSGeometry g1, const GEOSGeometry g2, double gridSize)

GEOSGeometry *	GEOSDifference (const GEOSGeometry ga, const GEOSGeometry gb)

GEOSGeometry *	GEOSDifferencePrec (const GEOSGeometry ga, const GEOSGeometry gb, double gridSize)

GEOSGeometry *	GEOSSymDifference (const GEOSGeometry ga, const GEOSGeometry gb)

GEOSGeometry *	GEOSSymDifferencePrec (const GEOSGeometry ga, const GEOSGeometry gb, double gridSize)

GEOSGeometry *	GEOSUnion (const GEOSGeometry ga, const GEOSGeometry gb)

GEOSGeometry *	GEOSUnionPrec (const GEOSGeometry ga, const GEOSGeometry gb, double gridSize)

GEOSGeometry *	GEOSUnaryUnion (const GEOSGeometry *g)

GEOSGeometry *	GEOSUnaryUnionPrec (const GEOSGeometry *g, double gridSize)

GEOSGeometry *	GEOSDisjointSubsetUnion (const GEOSGeometry *g)

GEOSGeometry *	GEOSClipByRect (const GEOSGeometry *g, double xmin, double ymin, double xmax, double ymax)

GEOSGeometry *	GEOSSharedPaths (const GEOSGeometry g1, const GEOSGeometry g2)

Buffer and Offset Curves
Functions for creating distance-based buffers and offset curves.
GEOSGeometry *	GEOSBuffer (const GEOSGeometry *g, double width, int quadsegs)

GEOSBufferParams *	GEOSBufferParams_create (void)

void	GEOSBufferParams_destroy (GEOSBufferParams *parms)

int	GEOSBufferParams_setEndCapStyle (GEOSBufferParams *p, int style)

int	GEOSBufferParams_setJoinStyle (GEOSBufferParams *p, int joinStyle)

int	GEOSBufferParams_setMitreLimit (GEOSBufferParams *p, double mitreLimit)

int	GEOSBufferParams_setQuadrantSegments (GEOSBufferParams *p, int quadSegs)

int	GEOSBufferParams_setSingleSided (GEOSBufferParams *p, int singleSided)

GEOSGeometry *	GEOSBufferWithParams (const GEOSGeometry g, const GEOSBufferParams p, double width)

GEOSGeometry *	GEOSBufferWithStyle (const GEOSGeometry *g, double width, int quadsegs, int endCapStyle, int joinStyle, double mitreLimit)

GEOSGeometry *	GEOSOffsetCurve (const GEOSGeometry *g, double width, int quadsegs, int joinStyle, double mitreLimit)

Coverages
Functions to work with coverages represented by lists of polygons that exactly share edge geometry.
GEOSGeometry *	GEOSCoverageUnion (const GEOSGeometry *g)

int	GEOSCoverageIsValid (const GEOSGeometry input, double gapWidth, GEOSGeometry *invalidEdges)

GEOSGeometry *	GEOSCoverageSimplifyVW (const GEOSGeometry *input, double tolerance, int preserveBoundary)

Noding and Polygonization
Functions computing noding of lines, and forming noded lines into polygons.
GEOSGeometry *	GEOSNode (const GEOSGeometry *g)

GEOSGeometry *	GEOSPolygonize (const GEOSGeometry *const geoms[], unsigned int ngeoms)

GEOSGeometry *	GEOSPolygonize_valid (const GEOSGeometry *const geoms[], unsigned int ngeoms)

GEOSGeometry *	GEOSPolygonizer_getCutEdges (const GEOSGeometry *const geoms[], unsigned int ngeoms)

GEOSGeometry *	GEOSPolygonize_full (const GEOSGeometry input, GEOSGeometry cuts, GEOSGeometry dangles, GEOSGeometry *invalid)

GEOSGeometry *	GEOSBuildArea (const GEOSGeometry *g)

Processing
Functions performing various geometric processes.
GEOSGeometry *	GEOSDensify (const GEOSGeometry *g, double tolerance)

GEOSGeometry *	GEOSLineMerge (const GEOSGeometry *g)

GEOSGeometry *	GEOSLineMergeDirected (const GEOSGeometry *g)

GEOSGeometry *	GEOSLineSubstring (const GEOSGeometry *g, double start_fraction, double end_fraction)

GEOSGeometry *	GEOSReverse (const GEOSGeometry *g)

GEOSGeometry *	GEOSSimplify (const GEOSGeometry *g, double tolerance)

GEOSGeometry *	GEOSTopologyPreserveSimplify (const GEOSGeometry *g, double tolerance)

GEOSGeometry *	GEOSGeom_extractUniquePoints (const GEOSGeometry *g)

int	GEOSHilbertCode (const GEOSGeometry geom, const GEOSGeometry extent, unsigned int level, unsigned int *code)

GEOSGeometry *	GEOSGeom_transformXY (const GEOSGeometry g, GEOSTransformXYCallback callback, void userdata)

GEOSGeometry *	GEOSGeom_transformXYZ (const GEOSGeometry g, GEOSTransformXYZCallback callback, void userdata)

GEOSGeometry *	GEOSSnap (const GEOSGeometry input, const GEOSGeometry snap_target, double tolerance)

GEOSGeometry *	GEOSGeom_setPrecision (const GEOSGeometry *g, double gridSize, int flags)

Spatial Predicates
Functions computing binary spatial predicates using the DE-9IM topology model.
char	GEOSDisjoint (const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSTouches (const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSIntersects (const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSCrosses (const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSWithin (const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSContains (const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSOverlaps (const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSEquals (const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSCovers (const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSCoveredBy (const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSEqualsExact (const GEOSGeometry g1, const GEOSGeometry g2, double tolerance)

char	GEOSEqualsIdentical (const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSRelatePattern (const GEOSGeometry g1, const GEOSGeometry g2, const char *imPattern)

char *	GEOSRelate (const GEOSGeometry g1, const GEOSGeometry g2)

char	GEOSRelatePatternMatch (const char intMatrix, const char imPattern)

char *	GEOSRelateBoundaryNodeRule (const GEOSGeometry g1, const GEOSGeometry g2, int bnr)

Prepared Geometry
A GEOSPreparedGeometry is a wrapper around GEOSGeometry that includes spatial indexing on the edges of the geometry. This allows spatial predicates to evaluate much faster, so for cases in which the same base geometry will be used over and over again for predicate tests, wrapping it in a GEOSPreparedGeometry is a best practice. Prepared Geometry supports some binary spatial predicates and distance calculations.
const GEOSPreparedGeometry *	GEOSPrepare (const GEOSGeometry *g)

void	GEOSPreparedGeom_destroy (const GEOSPreparedGeometry *g)

char	GEOSPreparedContains (const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedContainsXY (const GEOSPreparedGeometry *pg1, double x, double y)

char	GEOSPreparedContainsProperly (const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedCoveredBy (const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedCovers (const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedCrosses (const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedDisjoint (const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedIntersects (const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedIntersectsXY (const GEOSPreparedGeometry *pg1, double x, double y)

char	GEOSPreparedOverlaps (const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedTouches (const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedWithin (const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char *	GEOSPreparedRelate (const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

char	GEOSPreparedRelatePattern (const GEOSPreparedGeometry pg1, const GEOSGeometry g2, const char *imPattern)

GEOSCoordSequence *	GEOSPreparedNearestPoints (const GEOSPreparedGeometry pg1, const GEOSGeometry g2)

int	GEOSPreparedDistance (const GEOSPreparedGeometry pg1, const GEOSGeometry g2, double *dist)

char	GEOSPreparedDistanceWithin (const GEOSPreparedGeometry pg1, const GEOSGeometry g2, double dist)

STRtree
A GEOSSTRtree is a R-tree spatial index structure for two dimensional data. It uses the Sort-Tile-Recursive packing algorithm.
GEOSSTRtree *	GEOSSTRtree_create (size_t nodeCapacity)

int	GEOSSTRtree_build (GEOSSTRtree *tree)

void	GEOSSTRtree_insert (GEOSSTRtree tree, const GEOSGeometry g, void *item)

void	GEOSSTRtree_query (GEOSSTRtree tree, const GEOSGeometry g, GEOSQueryCallback callback, void *userdata)

const GEOSGeometry *	GEOSSTRtree_nearest (GEOSSTRtree tree, const GEOSGeometry geom)

const void *	GEOSSTRtree_nearest_generic (GEOSSTRtree tree, const void item, const GEOSGeometry itemEnvelope, GEOSDistanceCallback distancefn, void userdata)

void	GEOSSTRtree_iterate (GEOSSTRtree tree, GEOSQueryCallback callback, void userdata)

char	GEOSSTRtree_remove (GEOSSTRtree tree, const GEOSGeometry g, void *item)

void	GEOSSTRtree_destroy (GEOSSTRtree *tree)

Geometric Algorithms
Functions to compute basic geometric algorithms.
int	GEOSSegmentIntersection (double ax0, double ay0, double ax1, double ay1, double bx0, double by0, double bx1, double by1, double cx, double cy)

int	GEOSOrientationIndex (double Ax, double Ay, double Bx, double By, double Px, double Py)

WKT Reader and Writer
Functions for doing WKT I/O.
GEOSWKTReader *	GEOSWKTReader_create (void)

void	GEOSWKTReader_destroy (GEOSWKTReader *reader)

GEOSGeometry *	GEOSWKTReader_read (GEOSWKTReader reader, const char wkt)

void	GEOSWKTReader_setFixStructure (GEOSWKTReader *reader, char doFix)

GEOSWKTWriter *	GEOSWKTWriter_create (void)

void	GEOSWKTWriter_destroy (GEOSWKTWriter *writer)

char *	GEOSWKTWriter_write (GEOSWKTWriter writer, const GEOSGeometry g)

void	GEOSWKTWriter_setTrim (GEOSWKTWriter *writer, char trim)

void	GEOSWKTWriter_setRoundingPrecision (GEOSWKTWriter *writer, int precision)

void	GEOSWKTWriter_setOutputDimension (GEOSWKTWriter *writer, int dim)

int	GEOSWKTWriter_getOutputDimension (GEOSWKTWriter *writer)

void	GEOSWKTWriter_setOld3D (GEOSWKTWriter *writer, int useOld3D)

WKB Reader and Writer
Functions for doing WKB I/O.
GEOSWKBReader *	GEOSWKBReader_create (void)

void	GEOSWKBReader_destroy (GEOSWKBReader *reader)

void	GEOSWKBReader_setFixStructure (GEOSWKBReader *reader, char doFix)

GEOSGeometry *	GEOSWKBReader_read (GEOSWKBReader reader, const unsigned char wkb, size_t size)

GEOSGeometry *	GEOSWKBReader_readHEX (GEOSWKBReader reader, const unsigned char hex, size_t size)

GEOSWKBWriter *	GEOSWKBWriter_create (void)

void	GEOSWKBWriter_destroy (GEOSWKBWriter *writer)

unsigned char *	GEOSWKBWriter_write (GEOSWKBWriter writer, const GEOSGeometry g, size_t *size)

unsigned char *	GEOSWKBWriter_writeHEX (GEOSWKBWriter writer, const GEOSGeometry g, size_t *size)

int	GEOSWKBWriter_getOutputDimension (const GEOSWKBWriter *writer)

void	GEOSWKBWriter_setOutputDimension (GEOSWKBWriter *writer, int newDimension)

int	GEOSWKBWriter_getByteOrder (const GEOSWKBWriter *writer)

void	GEOSWKBWriter_setByteOrder (GEOSWKBWriter *writer, int byteOrder)

int	GEOSWKBWriter_getFlavor (const GEOSWKBWriter *writer)

void	GEOSWKBWriter_setFlavor (GEOSWKBWriter *writer, int flavor)

char	GEOSWKBWriter_getIncludeSRID (const GEOSWKBWriter *writer)

void	GEOSWKBWriter_setIncludeSRID (GEOSWKBWriter *writer, const char writeSRID)

GeoJSON Reader and Writer
Functions for doing GeoJSON I/O.
GEOSGeoJSONReader *	GEOSGeoJSONReader_create (void)

void	GEOSGeoJSONReader_destroy (GEOSGeoJSONReader *reader)

GEOSGeometry *	GEOSGeoJSONReader_readGeometry (GEOSGeoJSONReader reader, const char geojson)

GEOSGeoJSONWriter *	GEOSGeoJSONWriter_create (void)

void	GEOSGeoJSONWriter_destroy (GEOSGeoJSONWriter *writer)

char *	GEOSGeoJSONWriter_writeGeometry (GEOSGeoJSONWriter writer, const GEOSGeometry g, int indent)

DEPRECATED
Deprecated Functions. See description for replacement.
GEOSGeometry *	GEOSSingleSidedBuffer (const GEOSGeometry *g, double width, int quadsegs, int joinStyle, double mitreLimit, int leftSide)

GEOSGeometry *	GEOSSingleSidedBuffer_r (GEOSContextHandle_t handle, const GEOSGeometry *g, double width, int quadsegs, int joinStyle, double mitreLimit, int leftSide)

GEOSContextHandle_t	initGEOS_r (GEOSMessageHandler notice_function, GEOSMessageHandler error_function)

void	finishGEOS_r (GEOSContextHandle_t handle)

GEOSGeometry *	GEOSGeomFromWKT_r (GEOSContextHandle_t handle, const char *wkt)

char *	GEOSGeomToWKT_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

int	GEOS_getWKBOutputDims_r (GEOSContextHandle_t handle)

int	GEOS_setWKBOutputDims_r (GEOSContextHandle_t handle, int newDims)

int	GEOS_getWKBByteOrder_r (GEOSContextHandle_t handle)

int	GEOS_setWKBByteOrder_r (GEOSContextHandle_t handle, int byteOrder)

GEOSGeometry *	GEOSGeomFromWKB_buf_r (GEOSContextHandle_t handle, const unsigned char *wkb, size_t size)

unsigned char *	GEOSGeomToWKB_buf_r (GEOSContextHandle_t handle, const GEOSGeometry g, size_t size)

GEOSGeometry *	GEOSGeomFromHEX_buf_r (GEOSContextHandle_t handle, const unsigned char *hex, size_t size)

unsigned char *	GEOSGeomToHEX_buf_r (GEOSContextHandle_t handle, const GEOSGeometry g, size_t size)

GEOSGeometry *	GEOSGeomFromWKT (const char *wkt)

char *	GEOSGeomToWKT (const GEOSGeometry *g)

int	GEOS_getWKBOutputDims (void)

int	GEOS_setWKBOutputDims (int newDims)

int	GEOS_getWKBByteOrder (void)

int	GEOS_setWKBByteOrder (int byteOrder)

GEOSGeometry *	GEOSGeomFromWKB_buf (const unsigned char *wkb, size_t size)

unsigned char *	GEOSGeomToWKB_buf (const GEOSGeometry g, size_t size)

GEOSGeometry *	GEOSGeomFromHEX_buf (const unsigned char *hex, size_t size)

unsigned char *	GEOSGeomToHEX_buf (const GEOSGeometry g, size_t size)

GEOSGeometry *	GEOSUnionCascaded (const GEOSGeometry *g)

GEOSGeometry *	GEOSUnionCascaded_r (GEOSContextHandle_t handle, const GEOSGeometry *g)

Geometric Constructions
Functions for computing geometric constructions.
enum	GEOSPolygonHullParameterModes { GEOSHULL_PARAM_VERTEX_RATIO = 1 , GEOSHULL_PARAM_AREA_RATIO = 2 }

enum	GEOSVoronoiFlags { GEOS_VORONOI_ONLY_EDGES = 1 , GEOS_VORONOI_PRESERVE_ORDER = 2 }

GEOSGeometry *	GEOSEnvelope (const GEOSGeometry *g)

GEOSGeometry *	GEOSBoundary (const GEOSGeometry *g)

GEOSGeometry *	GEOSConvexHull (const GEOSGeometry *g)

GEOSGeometry *	GEOSConcaveHull (const GEOSGeometry *g, double ratio, unsigned int allowHoles)

GEOSGeometry *	GEOSConcaveHullByLength (const GEOSGeometry *g, double length, unsigned int allowHoles)

GEOSGeometry *	GEOSConcaveHullOfPolygons (const GEOSGeometry *g, double lengthRatio, unsigned int isTight, unsigned int isHolesAllowed)

GEOSGeometry *	GEOSPolygonHullSimplify (const GEOSGeometry *g, unsigned int isOuter, double vertexNumFraction)

GEOSGeometry *	GEOSPolygonHullSimplifyMode (const GEOSGeometry *g, unsigned int isOuter, unsigned int parameterMode, double parameter)

GEOSGeometry *	GEOSMinimumRotatedRectangle (const GEOSGeometry *g)

GEOSGeometry *	GEOSMaximumInscribedCircle (const GEOSGeometry *g, double tolerance)

GEOSGeometry *	GEOSLargestEmptyCircle (const GEOSGeometry obstacles, const GEOSGeometry boundary, double tolerance)

GEOSGeometry *	GEOSMinimumWidth (const GEOSGeometry *g)

GEOSGeometry *	GEOSPointOnSurface (const GEOSGeometry *g)

GEOSGeometry *	GEOSGetCentroid (const GEOSGeometry *g)

GEOSGeometry *	GEOSMinimumBoundingCircle (const GEOSGeometry g, double radius, GEOSGeometry **center)

GEOSGeometry *	GEOSDelaunayTriangulation (const GEOSGeometry *g, double tolerance, int onlyEdges)

GEOSGeometry *	GEOSConstrainedDelaunayTriangulation (const GEOSGeometry *g)

GEOSGeometry *	GEOSVoronoiDiagram (const GEOSGeometry g, const GEOSGeometry env, double tolerance, int flags)

Detailed Description

C API for the GEOS geometry algorithms library.

The C API is the supported API for using GEOS in your application/library/etc. The C API is kept stable, and deprecated function signatures are kept available over a long time period to allow transition time. While the C++ API is available, it may change at any time, and the ABI may not be stable between versions.

Important programming notes:

Call initGEOS() before using the library functions.
Call finishGEOS() when finished using the library.
To avoid memory leaks, call GEOSGeom_destroy() on GEOSGeometry objects, and call GEOSFree() on returned char * strings and byte buffers (unless marked const).
Functions ending with _r are thread safe (reentrant); see details in https://libgeos.org/development/rfcs/rfc03. To avoid accidental use of non-reentrant functions, define GEOS_USE_ONLY_R_API before including geos_c.h.

Typedef Documentation

◆ GEOSBufferParams

typedef struct GEOSBufParams_t GEOSBufferParams

Parameter object for buffering.

See also: GEOSBufferParams_create(); GEOSBufferParams_destroy()

◆ GEOSContextHandle_t

typedef struct GEOSContextHandle_HS* GEOSContextHandle_t

Type returned by GEOS_init_r(), for use with the functions ending in _r (the reentrant API).

Contexts must only be used from a single thread at a time.

◆ GEOSCoordSequence

typedef struct GEOSCoordSeq_t GEOSCoordSequence

Coordinate sequence type representing fixed-size lists of coordinates. Contains the list of vertices defining the location of a GEOSGeometry.

See also: GEOSCoordSeq_create(); GEOSCoordSeq_destroy()

◆ GEOSDistanceCallback

typedef int(* GEOSDistanceCallback) (const void *item1, const void *item2, double *distance, void *userdata)

Callback function for use in spatial index nearest neighbor calculations. Allows custom distance to be calculated between items in the index. Is passed two items, and sets the calculated distance between the items into the distance pointer. Extra data for the calculation can be passed via the userdata.

Parameters

item1	first of the pair of items to calculate distance between
item2	second of the pair of items to calculate distance between
distance	the distance between the items here
userdata	extra data for the calculation

Returns: 1 if distance calculation succeeds, 0 otherwise

See also: GEOSSTRtree_nearest_generic; GEOSSTRtree_iterate

◆ GEOSGeoJSONReader

typedef struct GEOSGeoJSONReader_t GEOSGeoJSONReader

Reader object to read GeoJSON format and construct a Geometry.

See also: GEOSGeoJSONReader_create; GEOSGeoJSONReader_create_r

◆ GEOSGeoJSONWriter

typedef struct GEOSGeoJSONWriter_t GEOSGeoJSONWriter

Writer object to turn a Geometry into GeoJSON.

See also: GEOSGeoJSONReader_create; GEOSGeoJSONReader_create_r

◆ GEOSGeometry

typedef struct GEOSGeom_t GEOSGeometry

The generic type for a geometry. A geometry can be a Point, LineString, Polygon, MultiPoint, MultiLineString, MultiPolygon, or GeometryCollection. The geometry type can be read with GEOSGeomTypeId. Most functions in GEOS have GEOSGeometry * as either a parameter or a return type.

See also: GEOSGeom_createPoint; GEOSGeom_createLineString; GEOSGeom_createPolygon; GEOSGeom_createCollection; GEOSGeom_destroy

◆ GEOSInterruptCallback

typedef void() GEOSInterruptCallback(void)

Callback function for use in interruption. The callback will be invoked before checking for interruption, so can be used to request it.

See also: GEOS_interruptRegisterCallback; GEOS_interruptRequest; GEOS_interruptCancel

◆ GEOSMakeValidParams

typedef struct GEOSMakeValidParams_t GEOSMakeValidParams

Parameter object for validity enforcement.

See also: GEOSMakeValidParams_create(); GEOSMakeValidParams_destroy()

◆ GEOSMessageHandler

typedef void(* GEOSMessageHandler) (GEOS_PRINTF_FORMAT const char *fmt,...) GEOS_PRINTF_FORMAT_ATTR(1

Callback function for passing GEOS error messages to parent process.

Set the GEOSMessageHandler function for error and notice messages using initGEOS or initGEOS_r.

Parameters

fmt	the message format template

◆ GEOSMessageHandler_r

typedef void(*) typedef void(* GEOSMessageHandler_r) (const char *message, void *userdata)

A GEOS message handler function.

Parameters

message	the message contents
userdata	the user data pointer that was passed to GEOS when registering this message handler.

See also: GEOSContext_setErrorMessageHandler; GEOSContext_setNoticeMessageHandler

◆ GEOSPreparedGeometry

typedef struct GEOSPrepGeom_t GEOSPreparedGeometry

Prepared geometry type.

See also: GEOSPrepare(); GEOSPreparedGeom_destroy()

◆ GEOSQueryCallback

typedef void(* GEOSQueryCallback) (void *item, void *userdata)

Callback function for use in spatial index search calls. Pass into the query function and handle query results as the index returns them.

See also: GEOSSTRtree_query

◆ GEOSSTRtree

typedef struct GEOSSTRtree_t GEOSSTRtree

STRTree index.

See also: GEOSSTRtree_create(); GEOSSTRtree_destroy()

◆ GEOSTransformXYCallback

typedef int(* GEOSTransformXYCallback) (double *x, double *y, void *userdata)

Callback function for use in GEOSGeom_transformXY. Allows custom function to be applied to x and y values for each coordinate in a geometry. Z and M values are unchanged by this function. Extra data for the calculation can be passed via the userdata.

Parameters

x	coordinate value to be updated
y	coordinate value to be updated
userdata	extra data for the calculation

Returns: 1 if calculation succeeded, 0 on failure

◆ GEOSTransformXYZCallback

typedef int(* GEOSTransformXYZCallback) (double *x, double *y, double *z, void *userdata)

Callback function for use in GEOSGeom_transformXYZ. Allows custom function to be applied to x, y and z values for each coordinate in a geometry. M values are unchanged by this function. Extra data for the calculation can be passed via the userdata.

Parameters

x	coordinate value to be updated
y	coordinate value to be updated
z	coordinate value to be updated
userdata	extra data for the calculation

Returns: 1 if calculation succeeded, 0 on failure

◆ GEOSWKBReader

typedef struct GEOSWKBReader_t GEOSWKBReader

Reader object to read Well-Known Binary (WKB) format and construct Geometry.

See also: GEOSWKBReader_create; GEOSWKBReader_create_r

◆ GEOSWKBWriter

typedef struct GEOSWKBWriter_t GEOSWKBWriter

Writer object to turn Geometry into Well-Known Binary (WKB).

See also: GEOSWKBWriter_create; GEOSWKBWriter_create_r

◆ GEOSWKTReader

typedef struct GEOSWKTReader_t GEOSWKTReader

Reader object to read Well-Known Text (WKT) format and construct Geometry.

See also: GEOSWKTReader_create; GEOSWKTReader_create_r

◆ GEOSWKTWriter

typedef struct GEOSWKTWriter_t GEOSWKTWriter

Writer object to turn Geometry into Well-Known Text (WKT).

See also: GEOSWKTWriter_create; GEOSWKTWriter_create_r

Enumeration Type Documentation

◆ GEOSBufCapStyles

enum GEOSBufCapStyles

Cap styles control the ends of buffered lines.

See also: GEOSBuffer

Enumerator
GEOSBUF_CAP_ROUND	End is rounded, with end point of original line in the centre of the round cap.
GEOSBUF_CAP_FLAT	End is flat, with end point of original line at the end of the buffer
GEOSBUF_CAP_SQUARE	End is flat, with end point of original line in the middle of a square enclosing that point

◆ GEOSBufJoinStyles

enum GEOSBufJoinStyles

Join styles control the buffer shape at bends in a line.

See also: GEOSBuffer

Enumerator
GEOSBUF_JOIN_ROUND	Join is rounded, essentially each line is terminated in a round cap. Form round corner.
GEOSBUF_JOIN_MITRE	Join is flat, with line between buffer edges, through the join point. Forms flat corner.
GEOSBUF_JOIN_BEVEL	Join is the point at which the two buffer edges intersect. Forms sharp corner.

◆ GEOSGeomTypes

enum GEOSGeomTypes

Geometry type number, used by functions returning or consuming geometry types.

See also: GEOSGeomType; GEOSGeomTypeId

Enumerator
GEOS_POINT	Point
GEOS_LINESTRING	Linestring
GEOS_LINEARRING	Linear ring, used within polygons
GEOS_POLYGON	Polygon
GEOS_MULTIPOINT	Multipoint, a homogeneous collection of points
GEOS_MULTILINESTRING	Multilinestring, a homogeneous collection of linestrings
GEOS_MULTIPOLYGON	Multipolygon, a homogeneous collection of polygons
GEOS_GEOMETRYCOLLECTION	Geometry collection, a heterogeneous collection of geometry

◆ GEOSMakeValidMethods

enum GEOSMakeValidMethods

Algorithm to use when repairing invalid geometries.

See also: GEOSMakeValidWithParams

Enumerator
GEOS_MAKE_VALID_LINEWORK	Original method, combines all rings into a set of noded lines and then extracts valid polygons from that linework.
GEOS_MAKE_VALID_STRUCTURE	Structured method, first makes all rings valid then merges shells and subtracts holes from shells to generate valid result. Assumes that holes and shells are correctly categorized.

◆ GEOSPolygonHullParameterModes

enum GEOSPolygonHullParameterModes

Controls the behavior of the GEOSPolygonHullSimplify parameter.

Enumerator
GEOSHULL_PARAM_VERTEX_RATIO	Fraction of input vertices retained
GEOSHULL_PARAM_AREA_RATIO	Ratio of simplified hull area to input area

◆ GEOSPrecisionRules

enum GEOSPrecisionRules

Controls the behavior of GEOSGeom_setPrecision() when altering the precision of a geometry.

Enumerator
GEOS_PREC_VALID_OUTPUT	The output is always valid. Collapsed geometry elements (including both polygons and lines) are removed.
GEOS_PREC_NO_TOPO	Precision reduction is performed pointwise. Output geometry may be invalid due to collapse or self-intersection. (This might be better called "GEOS_PREC_POINTWISE" - the current name is historical.)
GEOS_PREC_KEEP_COLLAPSED	Like the default mode, except that collapsed linear geometry elements are preserved. Collapsed polygonal input elements are removed.

◆ GEOSRelateBoundaryNodeRules

enum GEOSRelateBoundaryNodeRules

Controls the behavior of the result of GEOSRelate when returning DE9IM results for two geometries.

Enumerator
GEOSRELATE_BNR_MOD2	See geos::algorithm::BoundaryNodeRule::getBoundaryRuleMod2()
GEOSRELATE_BNR_OGC	Same as GEOSRELATE_BNR_MOD2
GEOSRELATE_BNR_ENDPOINT	See geos::algorithm::BoundaryNodeRule::getBoundaryEndPoint()
GEOSRELATE_BNR_MULTIVALENT_ENDPOINT	See geos::algorithm::BoundaryNodeRule::getBoundaryMultivalentEndPoint()
GEOSRELATE_BNR_MONOVALENT_ENDPOINT	See geos::algorithm::BoundaryNodeRule::getBoundaryMonovalentEndPoint()

◆ GEOSValidFlags

enum GEOSValidFlags

Change behaviour of validity testing in GEOSisValidDetail

Enumerator
GEOSVALID_ALLOW_SELFTOUCHING_RING_FORMING_HOLE	Allow self-touching rings to form a hole in a polygon.

◆ GEOSVoronoiFlags

enum GEOSVoronoiFlags

Change behaviour of GEOSVoronoiDiagram

Enumerator
GEOS_VORONOI_ONLY_EDGES	Return only edges of the Voronoi cells, as a MultiLineString
GEOS_VORONOI_PRESERVE_ORDER	Preserve order of inputs, such that the nth cell in the result corresponds to the nth vertex in the input. If this cannot be done, such as for inputs that contain repeated points, GEOSVoronoiDiagram will return NULL.

◆ GEOSWKBByteOrders

enum GEOSWKBByteOrders

Well-known binary byte orders used when writing to WKB.

See also: GEOSWKBWriter_setByteOrder

Enumerator
GEOS_WKB_XDR	Big Endian
GEOS_WKB_NDR	Little Endian

◆ GEOSWKBFlavors

enum GEOSWKBFlavors

Well-known binary flavors to use when writing to WKB. ISO flavour is more standard. Extended flavour supports 3D and SRID embedding. GEOS reads both transparently.

See also: GEOSWKBWriter_setFlavor

Enumerator
GEOS_WKB_EXTENDED	Extended
GEOS_WKB_ISO	ISO

Function Documentation

◆ finishGEOS()

void finishGEOS ( void )

For non-reentrant code, call when all GEOS operations are complete, cleans up global resources.

Since: 3.1

◆ finishGEOS_r()

void finishGEOS_r ( GEOSContextHandle_t handle )

Deprecated:: in 3.5.0, replaced by GEOS_finish_r()

◆ GEOS_finish_r()

void GEOS_finish_r ( GEOSContextHandle_t handle )

Free the memory associated with a GEOSContextHandle_t when you are finished calling GEOS functions.

Parameters

handle to be freed

Since: 3.5

◆ GEOS_getWKBByteOrder()

int GEOS_getWKBByteOrder ( void )

Deprecated:: use GEOSWKBWriter and GEOSWKBWriter_getByteOrder()

◆ GEOS_getWKBByteOrder_r()

int GEOS_getWKBByteOrder_r ( GEOSContextHandle_t handle )

Deprecated:: use GEOSWKBWriter and GEOSWKBWriter_getByteOrder_r()

◆ GEOS_getWKBOutputDims()

int GEOS_getWKBOutputDims ( void )

Deprecated:: use GEOSWKBWriter and GEOS_getWKBOutputDims()

◆ GEOS_getWKBOutputDims_r()

int GEOS_getWKBOutputDims_r ( GEOSContextHandle_t handle )

Deprecated:: use GEOSWKBWriter and GEOSWKBWriter_getOutputDimension_r()

◆ GEOS_init_r()

GEOSContextHandle_t GEOS_init_r ( void )

Allocate and initialize a context. Pass this context as the first argument when calling other *_r functions. Contexts must only be used from a single thread at a time.

Returns: a new GEOS context.

Since: 3.5

◆ GEOS_interruptCancel()

void GEOS_interruptCancel ( void )

Cancel a pending interruption request

Since: 3.4

◆ GEOS_interruptRegisterCallback()

GEOSInterruptCallback* GEOS_interruptRegisterCallback ( GEOSInterruptCallback * cb )

Register a function to be called when processing is interrupted.

Parameters

cb	Callback function to invoke

Returns: the previously configured callback

See also: GEOSInterruptCallback

Since: 3.4

◆ GEOS_interruptRequest()

void GEOS_interruptRequest ( void )

Request safe interruption of operations

Since: 3.4

◆ GEOS_printDouble()

int GEOS_printDouble	(	double	d,
		unsigned int	precision,
		char *	result
	)

Print the shortest representation of a double. Non-zero absolute values that are <1e-4 and >=1e+17 are formatted using scientific notation, and other values are formatted with positional notation with precision used for the max digits after decimal point.

Parameters

d	The number to format.
precision	The desired precision.
result	The buffer to write the result to, with a suggested size 28.

Returns: the length of the written string.

◆ GEOS_setWKBByteOrder()

int GEOS_setWKBByteOrder ( int byteOrder )

Deprecated:: use GEOSWKBWriter and GEOSWKBWriter_setByteOrder()

◆ GEOS_setWKBByteOrder_r()

int GEOS_setWKBByteOrder_r	(	GEOSContextHandle_t	handle,
		int	byteOrder
	)

Deprecated:: use GEOSWKBWriter and GEOSWKBWriter_setByteOrder_r()

◆ GEOS_setWKBOutputDims()

int GEOS_setWKBOutputDims ( int newDims )

Deprecated:: use GEOSWKBWriter and GEOS_setWKBOutputDims()

◆ GEOS_setWKBOutputDims_r()

int GEOS_setWKBOutputDims_r	(	GEOSContextHandle_t	handle,
		int	newDims
	)

Deprecated:: use GEOSWKBWriter and GEOSWKBWriter_setOutputDimension_r()

◆ GEOSArea()

int GEOSArea	(	const GEOSGeometry *	g,
		double *	area
	)

Calculate the area of a geometry.

Parameters

[in]	g	Input geometry
[out]	area	Pointer to be filled in with area result

Returns: 1 on success, 0 on exception.

Since: 2.2

◆ GEOSArea_r()

int GEOSArea_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double *	area
	)

See also: GEOSArea

◆ GEOSBoundary()

GEOSGeometry* GEOSBoundary ( const GEOSGeometry * g )

Returns the "boundary" of a geometry, as defined by the DE9IM:

the boundary of a polygon is the linear rings dividing the exterior from the interior
the boundary of a linestring is the end points
the boundary of a point is the point

Parameters

g	The input geometry

Returns: A newly allocated geometry of the boundary. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 2.2

◆ GEOSBoundary_r()

GEOSGeometry* GEOSBoundary_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSBoundary

◆ GEOSBuffer()

GEOSGeometry* GEOSBuffer	(	const GEOSGeometry *	g,
		double	width,
		int	quadsegs
	)

Buffer a geometry.

Parameters

g	The input geometry to be buffered.
width	The distance by which to expand the geometry (or contract) if the value is negative.
quadsegs	The number of segments per quadrant to generate. More segments provides a more "precise" buffer at the expense of size.

Returns: A GEOSGeometry of the buffered result. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 2.2

◆ GEOSBuffer_r()

GEOSGeometry* GEOSBuffer_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double	width,
		int	quadsegs
	)

See also: GEOSBuffer

◆ GEOSBufferParams_create()

GEOSBufferParams* GEOSBufferParams_create ( void )

Create a default GEOSBufferParams object for controlling the shape of buffered generated by GEOSBuffer.

Returns: A newly allocated GEOSBufferParams. NULL on exception. Caller is responsible for freeing with GEOSBufferParams_destroy().

Since: 3.3

◆ GEOSBufferParams_create_r()

GEOSBufferParams* GEOSBufferParams_create_r ( GEOSContextHandle_t handle )

See also: GEOSBufferParams_create

◆ GEOSBufferParams_destroy()

void GEOSBufferParams_destroy ( GEOSBufferParams * parms )

Destroy a GEOSBufferParams and free all associated memory.

Parameters

parms The object to destroy.

Since: 3.3

◆ GEOSBufferParams_destroy_r()

void GEOSBufferParams_destroy_r	(	GEOSContextHandle_t	handle,
		GEOSBufferParams *	parms
	)

See also: GEOSBufferParams_destroy

◆ GEOSBufferParams_setEndCapStyle()

int GEOSBufferParams_setEndCapStyle	(	GEOSBufferParams *	p,
		int	style
	)

Set the end cap type of a GEOSBufferParams to the desired style, which must be one enumerated in GEOSBufCapStyles.

Returns: 0 on exception, 1 on success.

Since: 3.3

◆ GEOSBufferParams_setEndCapStyle_r()

int GEOSBufferParams_setEndCapStyle_r	(	GEOSContextHandle_t	handle,
		GEOSBufferParams *	p,
		int	style
	)

See also: GEOSBufferParams_setEndCapStyle

◆ GEOSBufferParams_setJoinStyle()

int GEOSBufferParams_setJoinStyle	(	GEOSBufferParams *	p,
		int	joinStyle
	)

Set the join type of a GEOSBufferParams to the desired style, which must be one enumerated in GEOSBufJoinStyles.

Returns: 0 on exception, 1 on success.

Since: 3.3

◆ GEOSBufferParams_setJoinStyle_r()

int GEOSBufferParams_setJoinStyle_r	(	GEOSContextHandle_t	handle,
		GEOSBufferParams *	p,
		int	joinStyle
	)

See also: GEOSBufferParams_setJoinStyle

◆ GEOSBufferParams_setMitreLimit()

int GEOSBufferParams_setMitreLimit	(	GEOSBufferParams *	p,
		double	mitreLimit
	)

Set the mitre limit of a GEOSBufferParams to the desired size. For acute angles, a mitre join can extend very very far from the input geometry, which is probably not desired. The mitre limit places an upper bound on that.

Parameters

p	The GEOSBufferParams to operate on
mitreLimit	The limit to set

Returns: 0 on exception, 1 on success.

Since: 3.3

◆ GEOSBufferParams_setMitreLimit_r()

int GEOSBufferParams_setMitreLimit_r	(	GEOSContextHandle_t	handle,
		GEOSBufferParams *	p,
		double	mitreLimit
	)

See also: GEOSBufferParams_setMitreLimit

◆ GEOSBufferParams_setQuadrantSegments()

int GEOSBufferParams_setQuadrantSegments	(	GEOSBufferParams *	p,
		int	quadSegs
	)

Set the number of segments to use to stroke each quadrant of circular arcs generated by the buffering process. More segments means a smoother output, but with larger size.

Parameters

p	The GEOSBufferParams to operate on
quadSegs	Number of segments per quadrant

Returns: 0 on exception, 1 on success.

Since: 3.3

◆ GEOSBufferParams_setQuadrantSegments_r()

int GEOSBufferParams_setQuadrantSegments_r	(	GEOSContextHandle_t	handle,
		GEOSBufferParams *	p,
		int	quadSegs
	)

See also: GEOSBufferParams_setQuadrantSegments

◆ GEOSBufferParams_setSingleSided()

int GEOSBufferParams_setSingleSided	(	GEOSBufferParams *	p,
		int	singleSided
	)

Sets whether the computed buffer should be single-sided. A single-sided buffer is constructed on only one side of each input line.

See also: geos::operation::buffer::BufferParameters::setSingleSided

Parameters

p	The GEOSBufferParams to operate on
singleSided	Set to 1 for single-sided output 0 otherwise

Returns: 0 on exception, 1 on success.

Since: 3.3

◆ GEOSBufferParams_setSingleSided_r()

int GEOSBufferParams_setSingleSided_r	(	GEOSContextHandle_t	handle,
		GEOSBufferParams *	p,
		int	singleSided
	)

See also: GEOSBufferParams_setSingleSided

◆ GEOSBufferWithParams()

GEOSGeometry* GEOSBufferWithParams	(	const GEOSGeometry *	g,
		const GEOSBufferParams *	p,
		double	width
	)

Generates a buffer using the special parameters in the GEOSBufferParams

Parameters

g	The geometry to buffer
p	The parameters to apply to the buffer process
width	The buffer distance

Returns: The buffered geometry, or NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 3.3

◆ GEOSBufferWithParams_r()

GEOSGeometry* GEOSBufferWithParams_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		const GEOSBufferParams *	p,
		double	width
	)

See also: GEOSBufferWithParams

◆ GEOSBufferWithStyle()

GEOSGeometry* GEOSBufferWithStyle	(	const GEOSGeometry *	g,
		double	width,
		int	quadsegs,
		int	endCapStyle,
		int	joinStyle,
		double	mitreLimit
	)

Generate a buffer using the provided style parameters.

Parameters

g	The geometry to buffer
width	Width of the buffer
quadsegs	Number of segments per quadrant
endCapStyle	See GEOSBufCapStyles
joinStyle	See GEOSBufJoinStyles
mitreLimit	See GEOSBufferParams_setMitreLimit

Returns: The buffered geometry, or NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 3.2

◆ GEOSBufferWithStyle_r()

GEOSGeometry* GEOSBufferWithStyle_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double	width,
		int	quadsegs,
		int	endCapStyle,
		int	joinStyle,
		double	mitreLimit
	)

See also: GEOSBufferWithStyle

◆ GEOSBuildArea()

GEOSGeometry* GEOSBuildArea ( const GEOSGeometry * g )

Perform a polygonization using all the linework, assuming that rings contained within rings are empty holes, rather then extra polygons.

Parameters

g	The input linework

Returns: The polygonal output Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::operation::polygonize::BuildArea

Since: 3.8

◆ GEOSBuildArea_r()

GEOSGeometry* GEOSBuildArea_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSBuildArea

◆ GEOSClipByRect()

GEOSGeometry* GEOSClipByRect	(	const GEOSGeometry *	g,
		double	xmin,
		double	ymin,
		double	xmax,
		double	ymax
	)

Intersection optimized for a rectangular clipping polygon. Supposed to be faster than using GEOSIntersection(). Not guaranteed to return valid results.

Parameters

g	The input geometry to be clipped
xmin	Left bound of clipping rectangle
ymin	Lower bound of clipping rectangle
xmax	Right bound of clipping rectangle
ymax	Upper bound of clipping rectangle

Returns: The clipped geometry or NULL on exception Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::operation::intersection::RectangleIntersection

Since: 3.5

◆ GEOSClipByRect_r()

GEOSGeometry* GEOSClipByRect_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double	xmin,
		double	ymin,
		double	xmax,
		double	ymax
	)

See also: GEOSClipByRect

◆ GEOSConcaveHull()

GEOSGeometry* GEOSConcaveHull	(	const GEOSGeometry *	g,
		double	ratio,
		unsigned int	allowHoles
	)

Returns a "concave hull" of a geometry. A concave hull is a polygon which contains all the points of the input, but is a better approximation than the convex hull to the area occupied by the input. Frequently used to convert a multi-point into a polygonal area. that contains all the points in the input Geometry.

A set of points has a sequence of hulls of increasing concaveness, determined by a numeric target parameter. The concave hull is constructed by removing the longest outer edges of the Delaunay Triangulation of the space between the polygons, until the target criterion parameter is reached. This can be expressed as a ratio between the lengths of the longest and shortest edges. 1 produces the convex hull; 0 produces a hull with maximum concaveness

Parameters

g	The input geometry
ratio	The edge length ratio value, between 0 and 1.
allowHoles	When non-zero, the polygonal output may contain holes.

Returns: A newly allocated geometry of the concave hull. NULL on exception.

Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::algorithm::hull::ConcaveHull; GEOSConcaveHullByLength; GEOSConcaveHullOfPolygons; GEOSConvexHull

Since: 3.11

◆ GEOSConcaveHull_r()

GEOSGeometry* GEOSConcaveHull_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double	ratio,
		unsigned int	allowHoles
	)

See also: GEOSConcaveHull

◆ GEOSConcaveHullByLength()

GEOSGeometry* GEOSConcaveHullByLength	(	const GEOSGeometry *	g,
		double	length,
		unsigned int	allowHoles
	)

Returns a "concave hull" of a geometry. A concave hull is a polygon which contains all the points of the input, but is a better approximation than the convex hull to the area occupied by the input. Frequently used to convert a multi-point into a polygonal area. that contains all the points in the input Geometry.

A set of points has a sequence of hulls of increasing concaveness, determined by a numeric target parameter. The concave hull is constructed by removing the longest outer edges of the Delaunay Triangulation of the space between the polygons, until the specified maximm edge length is reached. A large value produces the convex hull, 0 produces the hull of maximum concaveness.

Parameters

g	The input geometry
length	The maximum edge length (0 or greater)
allowHoles	When non-zero, the polygonal output may contain holes.

Returns: A newly allocated geometry of the concave hull. NULL on exception.

Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::algorithm::hull::ConcaveHull; GEOSConcaveHull; GEOSConcaveHullOfPolygons; GEOSConvexHull

Since: 3.12

◆ GEOSConcaveHullByLength_r()

GEOSGeometry* GEOSConcaveHullByLength_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double	ratio,
		unsigned int	allowHoles
	)

See also: GEOSConcaveHullByLength

◆ GEOSConcaveHullOfPolygons()

GEOSGeometry* GEOSConcaveHullOfPolygons	(	const GEOSGeometry *	g,
		double	lengthRatio,
		unsigned int	isTight,
		unsigned int	isHolesAllowed
	)

Constructs a concave hull of a set of polygons, respecting the polygons as constraints.

A concave hull is a (possibly) non-convex polygon containing all the input polygons. The computed hull "fills the gap" between the polygons, and does not intersect their interior. A set of polygons has a sequence of hulls of increasing concaveness, determined by a numeric target parameter.

The concave hull is constructed by removing the longest outer edges of the Delaunay Triangulation of the space between the polygons, until the target criterion parameter is reached. The "Maximum Edge Length" parameter limits the length of the longest edge between polygons to be no larger than this value. This can be expressed as a ratio between the lengths of the longest and shortest edges.

The input polygons must be a valid MultiPolygon (i.e. they must be non-overlapping).

Parameters

g	the valid MultiPolygon geometry to process
lengthRatio	specifies the Maximum Edge Length as a fraction of the difference between the longest and shortest edge lengths between the polygons. This normalizes the Maximum Edge Length to be scale-free. A value of 1 produces the convex hull; a value of 0 produces the original polygons.
isHolesAllowed	is the concave hull allowed to contain holes?
isTight	does the hull follow the outer boundaries of the input polygons.

Returns: A newly allocated geometry of the concave hull. NULL on exception.

Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::algorithm::hull::ConcaveHullOfPolygons; GEOSConcaveHull; GEOSConvexHull

Since: 3.11

◆ GEOSConcaveHullOfPolygons_r()

GEOSGeometry* GEOSConcaveHullOfPolygons_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double	lengthRatio,
		unsigned int	isTight,
		unsigned int	isHolesAllowed
	)

See also: GEOSConcaveHullOfPolygons

◆ GEOSConstrainedDelaunayTriangulation()

GEOSGeometry* GEOSConstrainedDelaunayTriangulation ( const GEOSGeometry * g )

Return a constrained Delaunay triangulation of the vertices of the given polygon(s). For non-polygonal inputs, returns an empty geometry collection.

Parameters

g	the input geometry whose rings will be used as input

Returns: A newly allocated geometry. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 3.10

◆ GEOSConstrainedDelaunayTriangulation_r()

GEOSGeometry* GEOSConstrainedDelaunayTriangulation_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSConstrainedDelaunayTriangulation

◆ GEOSContains()

char GEOSContains	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

Tests if geometry g2 is completely within g1, but not wholly contained in the boundary of g1.

Parameters

g1	Input geometry
g2	Input geometry

Returns: 1 on true, 0 on false, 2 on exception

See also: geos::geom::Geometry::contains

Since: 2.2

◆ GEOSContains_r()

char GEOSContains_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

See also: GEOSContains

◆ GEOSContext_setErrorHandler_r()

GEOSMessageHandler GEOSContext_setErrorHandler_r	(	GEOSContextHandle_t	extHandle,
		GEOSMessageHandler	ef
	)

Set the notice handler callback function for run-time error messages.

Parameters

extHandle	the GEOS context from GEOS_init_r
ef	the handler callback

Returns: the previously configured message handler or NULL if no message handler was configured

Since: 3.3

◆ GEOSContext_setErrorMessageHandler_r()

GEOSMessageHandler_r GEOSContext_setErrorMessageHandler_r	(	GEOSContextHandle_t	extHandle,
		GEOSMessageHandler_r	ef,
		void *	userData
	)

Sets an error message handler on the given GEOS context.

Parameters

extHandle	the GEOS context
ef	the message handler
userData	optional user data pointer that will be passed to the message handler

Returns: the previously configured message handler or NULL if no message handler was configured

Since: 3.5

◆ GEOSContext_setNoticeHandler_r()

GEOSMessageHandler GEOSContext_setNoticeHandler_r	(	GEOSContextHandle_t	extHandle,
		GEOSMessageHandler	nf
	)

Set the notice handler callback function for run-time notice messages.

Parameters

extHandle	the context returned by GEOS_init_r.
nf	the handler callback

Returns: the previously configured message handler or NULL if no message handler was configured

Since: 3.3

◆ GEOSContext_setNoticeMessageHandler_r()

GEOSMessageHandler_r GEOSContext_setNoticeMessageHandler_r	(	GEOSContextHandle_t	extHandle,
		GEOSMessageHandler_r	nf,
		void *	userData
	)

Sets a notice message handler on the given GEOS context.

Parameters

extHandle	the GEOS context from GEOS_init_r
nf	the message handler
userData	optional user data pointer that will be passed to the message handler

Returns: the previously configured message handler or NULL if no message handler was configured

Since: 3.5

◆ GEOSConvexHull()

GEOSGeometry* GEOSConvexHull ( const GEOSGeometry * g )

Returns convex hull of a geometry. The smallest convex Geometry that contains all the points in the input Geometry

Parameters

g	The input geometry

Returns: A newly allocated geometry of the convex hull. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::operation::overlayng::OverlayNG

Since: 2.2

◆ GEOSConvexHull_r()

GEOSGeometry* GEOSConvexHull_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSConvexHull

◆ GEOSCoordSeq_clone()

GEOSCoordSequence* GEOSCoordSeq_clone ( const GEOSCoordSequence * s )

Clone a coordinate sequence.

Parameters

s	the coordinate sequence to clone

Returns: a copy of the coordinate sequence or NULL on exception

Since: 2.2

◆ GEOSCoordSeq_clone_r()

GEOSCoordSequence* GEOSCoordSeq_clone_r	(	GEOSContextHandle_t	handle,
		const GEOSCoordSequence *	s
	)

See also: GEOSCoordSeq_clone

◆ GEOSCoordSeq_copyFromArrays()

GEOSCoordSequence* GEOSCoordSeq_copyFromArrays	(	const double *	x,
		const double *	y,
		const double *	z,
		const double *	m,
		unsigned int	size
	)

Create a coordinate sequence by copying from arrays of doubles

Parameters

x	array of x coordinates
y	array of y coordinates
z	array of z coordinates, or NULL
m	array of m coordinates, or NULL
size	length of each array

Returns: the sequence or NULL on exception

Since: 3.10

◆ GEOSCoordSeq_copyFromArrays_r()

GEOSCoordSequence* GEOSCoordSeq_copyFromArrays_r	(	GEOSContextHandle_t	handle,
		const double *	x,
		const double *	y,
		const double *	z,
		const double *	m,
		unsigned int	size
	)

See also: GEOSCoordSeq_copyFromArrays

◆ GEOSCoordSeq_copyFromBuffer()

GEOSCoordSequence* GEOSCoordSeq_copyFromBuffer	(	const double *	buf,
		unsigned int	size,
		int	hasZ,
		int	hasM
	)

Create a coordinate sequence by copying from an interleaved buffer of doubles (e.g., XYXY or XYZXYZ)

Parameters

buf	pointer to buffer
size	number of coordinates in the sequence
hasZ	does buffer have Z values?
hasM	does buffer have M values?

Returns: the sequence or NULL on exception

Since: 3.10

◆ GEOSCoordSeq_copyFromBuffer_r()

GEOSCoordSequence* GEOSCoordSeq_copyFromBuffer_r	(	GEOSContextHandle_t	handle,
		const double *	buf,
		unsigned int	size,
		int	hasZ,
		int	hasM
	)

See also: GEOSCoordSeq_copyFromBuffer

◆ GEOSCoordSeq_copyToArrays()

int GEOSCoordSeq_copyToArrays	(	const GEOSCoordSequence *	s,
		double *	x,
		double *	y,
		double *	z,
		double *	m
	)

Copy the contents of a coordinate sequence to arrays of doubles

Parameters

s	sequence to copy
x	array to which x values should be copied
y	array to which y values should be copied
z	array to which z values should be copied, or NULL
m	array to which m values should be copied, or NULL

Returns: 1 on success, 0 on error

Since: 3.10

◆ GEOSCoordSeq_copyToArrays_r()

int GEOSCoordSeq_copyToArrays_r	(	GEOSContextHandle_t	handle,
		const GEOSCoordSequence *	s,
		double *	x,
		double *	y,
		double *	z,
		double *	m
	)

See also: GEOSCoordSeq_copyToArrays

◆ GEOSCoordSeq_copyToBuffer()

int GEOSCoordSeq_copyToBuffer	(	const GEOSCoordSequence *	s,
		double *	buf,
		int	hasZ,
		int	hasM
	)

Copy the contents of a coordinate sequence to an interleaved buffer of doubles (e.g., XYXY or XYZXYZ)

Parameters

s	sequence to copy
buf	buffer to which coordinates should be copied
hasZ	copy Z values to buffer?
hasM	copy M values to buffer?

Returns: 1 on success, 0 on error

Since: 3.10

◆ GEOSCoordSeq_copyToBuffer_r()

int GEOSCoordSeq_copyToBuffer_r	(	GEOSContextHandle_t	handle,
		const GEOSCoordSequence *	s,
		double *	buf,
		int	hasZ,
		int	hasM
	)

See also: GEOSCoordSeq_copyToBuffer

◆ GEOSCoordSeq_create()

GEOSCoordSequence* GEOSCoordSeq_create	(	unsigned int	size,
		unsigned int	dims
	)

Create a coordinate sequence.

Parameters

size	number of coordinates in the sequence
dims	dimensionality of the coordinates (2, 3 or 4)

Returns: the sequence or NULL on exception

Since: 2.2

◆ GEOSCoordSeq_create_r()

GEOSCoordSequence* GEOSCoordSeq_create_r	(	GEOSContextHandle_t	handle,
		unsigned int	size,
		unsigned int	dims
	)

See also: GEOSCoordSeq_create

◆ GEOSCoordSeq_destroy()

void GEOSCoordSeq_destroy ( GEOSCoordSequence * s )

Destroy a coordinate sequence, freeing all memory.

Parameters

s	the coordinate sequence to destroy

Since: 2.2

◆ GEOSCoordSeq_destroy_r()

void GEOSCoordSeq_destroy_r	(	GEOSContextHandle_t	handle,
		GEOSCoordSequence *	s
	)

See also: GEOSCoordSeq_destroy

◆ GEOSCoordSeq_getDimensions()

int GEOSCoordSeq_getDimensions	(	const GEOSCoordSequence *	s,
		unsigned int *	dims
	)

Get dimension info from a coordinate sequence.

Parameters

[in]	s	the coordinate sequence
[out]	dims	pointer where dimension value will be placed

Returns: 0 on exception

Since: 2.2

◆ GEOSCoordSeq_getDimensions_r()

int GEOSCoordSeq_getDimensions_r	(	GEOSContextHandle_t	handle,
		const GEOSCoordSequence *	s,
		unsigned int *	dims
	)

See also: GEOSCoordSeq_getDimensions

◆ GEOSCoordSeq_getOrdinate()

int GEOSCoordSeq_getOrdinate	(	const GEOSCoordSequence *	s,
		unsigned int	idx,
		unsigned int	dim,
		double *	val
	)

Read Nth ordinate value from a coordinate sequence.

Parameters

[in]	s	the coordinate sequence
[in]	idx	the index of the coordinate to alter, zero based
[in]	dim	the dimension number of the ordinate to read, zero based
[out]	val	pointer where ordinate value will be placed

Returns: 0 on exception

Since: 2.2

◆ GEOSCoordSeq_getOrdinate_r()

int GEOSCoordSeq_getOrdinate_r	(	GEOSContextHandle_t	handle,
		const GEOSCoordSequence *	s,
		unsigned int	idx,
		unsigned int	dim,
		double *	val
	)

See also: GEOSCoordSeq_getOrdinate

◆ GEOSCoordSeq_getSize()

int GEOSCoordSeq_getSize	(	const GEOSCoordSequence *	s,
		unsigned int *	size
	)

Get size info from a coordinate sequence.

Parameters

[in]	s	the coordinate sequence
[out]	size	pointer where size value will be placed

Returns: 0 on exception

Since: 2.2

◆ GEOSCoordSeq_getSize_r()

int GEOSCoordSeq_getSize_r	(	GEOSContextHandle_t	handle,
		const GEOSCoordSequence *	s,
		unsigned int *	size
	)

See also: GEOSCoordSeq_getSize

◆ GEOSCoordSeq_getX()

int GEOSCoordSeq_getX	(	const GEOSCoordSequence *	s,
		unsigned int	idx,
		double *	val
	)

Read X ordinate values from a coordinate sequence.

Parameters

s	the coordinate sequence
idx	the index of the coordinate to alter, zero based
val	pointer where ordinate value will be placed

Returns: 0 on exception

Since: 2.2

◆ GEOSCoordSeq_getX_r()

int GEOSCoordSeq_getX_r	(	GEOSContextHandle_t	handle,
		const GEOSCoordSequence *	s,
		unsigned int	idx,
		double *	val
	)

See also: GEOSCoordSeq_getX

◆ GEOSCoordSeq_getXY()

int GEOSCoordSeq_getXY	(	const GEOSCoordSequence *	s,
		unsigned int	idx,
		double *	x,
		double *	y
	)

Read X and Y ordinate values from a coordinate sequence.

Parameters

s	the coordinate sequence
idx	the index of the coordinate to alter, zero based
x	pointer where ordinate X value will be placed
y	pointer where ordinate Y value will be placed

Returns: 0 on exception

Since: 3.8

◆ GEOSCoordSeq_getXY_r()

int GEOSCoordSeq_getXY_r	(	GEOSContextHandle_t	handle,
		const GEOSCoordSequence *	s,
		unsigned int	idx,
		double *	x,
		double *	y
	)

See also: GEOSCoordSeq_getXY

◆ GEOSCoordSeq_getXYZ()

int GEOSCoordSeq_getXYZ	(	const GEOSCoordSequence *	s,
		unsigned int	idx,
		double *	x,
		double *	y,
		double *	z
	)

Read X and Y ordinate values from a coordinate sequence.

Parameters

s	the coordinate sequence
idx	the index of the coordinate to alter, zero based
x	pointer where ordinate X value will be placed
y	pointer where ordinate Y value will be placed
z	pointer where ordinate Z value will be placed

Returns: 0 on exception

Since: 3.8

◆ GEOSCoordSeq_getXYZ_r()

int GEOSCoordSeq_getXYZ_r	(	GEOSContextHandle_t	handle,
		const GEOSCoordSequence *	s,
		unsigned int	idx,
		double *	x,
		double *	y,
		double *	z
	)

See also: GEOSCoordSeq_getXYZ

◆ GEOSCoordSeq_getY()

int GEOSCoordSeq_getY	(	const GEOSCoordSequence *	s,
		unsigned int	idx,
		double *	val
	)

Read Y ordinate values from a coordinate sequence.

Parameters

s	the coordinate sequence
idx	the index of the coordinate to alter, zero based
val	pointer where ordinate value will be placed

Returns: 0 on exception

Since: 2.2

◆ GEOSCoordSeq_getY_r()

int GEOSCoordSeq_getY_r	(	GEOSContextHandle_t	handle,
		const GEOSCoordSequence *	s,
		unsigned int	idx,
		double *	val
	)

See also: GEOSCoordSeq_getY

◆ GEOSCoordSeq_getZ()

int GEOSCoordSeq_getZ	(	const GEOSCoordSequence *	s,
		unsigned int	idx,
		double *	val
	)

Read Z ordinate values from a coordinate sequence.

Parameters

s	the coordinate sequence
idx	the index of the coordinate to alter, zero based
val	pointer where ordinate value will be placed

Returns: 0 on exception

Since: 2.2

◆ GEOSCoordSeq_getZ_r()

int GEOSCoordSeq_getZ_r	(	GEOSContextHandle_t	handle,
		const GEOSCoordSequence *	s,
		unsigned int	idx,
		double *	val
	)

See also: GEOSCoordSeq_getZ

◆ GEOSCoordSeq_isCCW()

int GEOSCoordSeq_isCCW	(	const GEOSCoordSequence *	s,
		char *	is_ccw
	)

Check orientation of a coordinate sequence. Closure of the sequence is assumed. Invalid (collapsed) or short (fewer than 4 points) sequences return false.

Parameters

s	the coordinate sequence
is_ccw	pointer for ccw value, 1 if counter-clockwise orientation, 0 otherwise

Returns: 0 on exception, 1 on success

Since: 3.7

◆ GEOSCoordSeq_isCCW_r()

int GEOSCoordSeq_isCCW_r	(	GEOSContextHandle_t	handle,
		const GEOSCoordSequence *	s,
		char *	is_ccw
	)

See also: GEOSCoordSeq_isCCW

◆ GEOSCoordSeq_setOrdinate()

int GEOSCoordSeq_setOrdinate	(	GEOSCoordSequence *	s,
		unsigned int	idx,
		unsigned int	dim,
		double	val
	)

Set Nth ordinate value in a coordinate sequence.

Parameters

s	the coordinate sequence
idx	the index of the coordinate to alter, zero based
dim	the dimension number of the ordinate to alter, zero based
val	the value to set the ordinate to

Returns: 0 on exception

Since: 2.2

◆ GEOSCoordSeq_setOrdinate_r()

int GEOSCoordSeq_setOrdinate_r	(	GEOSContextHandle_t	handle,
		GEOSCoordSequence *	s,
		unsigned int	idx,
		unsigned int	dim,
		double	val
	)

See also: GEOSCoordSeq_setOrdinate

◆ GEOSCoordSeq_setX()

int GEOSCoordSeq_setX	(	GEOSCoordSequence *	s,
		unsigned int	idx,
		double	val
	)

Set X ordinate values in a coordinate sequence.

Parameters

s	the coordinate sequence
idx	the index of the coordinate to alter, zero based
val	the value to set the ordinate to

Returns: 0 on exception

Since: 2.2

◆ GEOSCoordSeq_setX_r()

int GEOSCoordSeq_setX_r	(	GEOSContextHandle_t	handle,
		GEOSCoordSequence *	s,
		unsigned int	idx,
		double	val
	)

See also: GEOSCoordSeq_setX

◆ GEOSCoordSeq_setXY()

int GEOSCoordSeq_setXY	(	GEOSCoordSequence *	s,
		unsigned int	idx,
		double	x,
		double	y
	)

Set X and Y ordinate values in a coordinate sequence simultaneously.

Parameters

s	the coordinate sequence
idx	the index of the coordinate to alter, zero based
x	the value to set the X ordinate to
y	the value to set the Y ordinate to

Returns: 0 on exception

Since: 3.8

◆ GEOSCoordSeq_setXY_r()

int GEOSCoordSeq_setXY_r	(	GEOSContextHandle_t	handle,
		GEOSCoordSequence *	s,
		unsigned int	idx,
		double	x,
		double	y
	)

See also: GEOSCoordSeq_setXY

◆ GEOSCoordSeq_setXYZ()

int GEOSCoordSeq_setXYZ	(	GEOSCoordSequence *	s,
		unsigned int	idx,
		double	x,
		double	y,
		double	z
	)

Set X, Y and Z ordinate values in a coordinate sequence simultaneously.

Parameters

s	the coordinate sequence
idx	the index of the coordinate to alter, zero based
x	the value to set the X ordinate to
y	the value to set the Y ordinate to
z	the value to set the Z ordinate to

Returns: 0 on exception

Since: 3.8

◆ GEOSCoordSeq_setXYZ_r()

int GEOSCoordSeq_setXYZ_r	(	GEOSContextHandle_t	handle,
		GEOSCoordSequence *	s,
		unsigned int	idx,
		double	x,
		double	y,
		double	z
	)

See also: GEOSCoordSeq_setXYZ

◆ GEOSCoordSeq_setY()

int GEOSCoordSeq_setY	(	GEOSCoordSequence *	s,
		unsigned int	idx,
		double	val
	)

Set Y ordinate values in a coordinate sequence.

Parameters

s	the coordinate sequence
idx	the index of the coordinate to alter, zero based
val	the value to set the ordinate to

Returns: 0 on exception

Since: 2.2

◆ GEOSCoordSeq_setY_r()

int GEOSCoordSeq_setY_r	(	GEOSContextHandle_t	handle,
		GEOSCoordSequence *	s,
		unsigned int	idx,
		double	val
	)

See also: GEOSCoordSeq_setY

◆ GEOSCoordSeq_setZ()

int GEOSCoordSeq_setZ	(	GEOSCoordSequence *	s,
		unsigned int	idx,
		double	val
	)

Set Z ordinate values in a coordinate sequence.

Parameters

s	the coordinate sequence
idx	the index of the coordinate to alter, zero based
val	the value to set the ordinate to

Returns: 0 on exception

Since: 2.2

◆ GEOSCoordSeq_setZ_r()

int GEOSCoordSeq_setZ_r	(	GEOSContextHandle_t	handle,
		GEOSCoordSequence *	s,
		unsigned int	idx,
		double	val
	)

See also: GEOSCoordSeq_setZ

◆ GEOSCoverageIsValid()

int GEOSCoverageIsValid	(	const GEOSGeometry *	input,
		double	gapWidth,
		GEOSGeometry **	invalidEdges
	)

Analyze a coverage (represented as a collection of polygonal geometry with exactly matching edge geometry) to find places where the assumption of exactly matching edges is not met.

Parameters

input	The polygonal coverage to access, stored in a geometry collection. All members must be POLYGON or MULTIPOLYGON.
gapWidth	The maximum width of gaps to detect.
invalidEdges	When there are invalidities in the coverage, this pointer will be set with a geometry collection of the same length as the input, with a MULTILINESTRING of the error edges for each invalid polygon, or an EMPTY where the polygon is a valid participant in the coverage. Pass NULL if you do not want the invalid edges returned.

Returns: A value of 1 for a valid coverage, 0 for invalid and 2 for an exception or error. Invalidity includes polygons that overlap, that have gaps smaller than the gapWidth, or non-polygonal entries in the input collection.

Since: 3.12

◆ GEOSCoverageIsValid_r()

int GEOSCoverageIsValid_r	(	GEOSContextHandle_t	extHandle,
		const GEOSGeometry *	input,
		double	gapWidth,
		GEOSGeometry **	output
	)

See also: GEOSCoverageIsValid

◆ GEOSCoverageSimplifyVW()

GEOSGeometry* GEOSCoverageSimplifyVW	(	const GEOSGeometry *	input,
		double	tolerance,
		int	preserveBoundary
	)

Operates on a coverage (represented as a list of polygonal geometry with exactly matching edge geometry) to apply a Visvalingam–Whyatt simplification to the edges, reducing complexity in proportion with the provided tolerance, while retaining a valid coverage (no edges will cross or touch after the simplification). Geometries never disappear, but they may be simplified down to just a triangle. Also, some invalid geoms (such as Polygons which have too few non-repeated points) will be returned unchanged. If the input dataset is not a valid coverage due to overlaps, it will still be simplified, but invalid topology such as crossing edges will still be invalid.

Parameters

input	The polygonal coverage to access, stored in a geometry collection. All members must be POLYGON or MULTIPOLYGON.
tolerance	A tolerance parameter in linear units.
preserveBoundary	Use 1 to preserve the outside edges of the coverage without simplification, 0 to allow them to be simplified.

Returns: A collection containing the simplified geometries, or null on error.

Since: 3.12

◆ GEOSCoverageSimplifyVW_r()

GEOSGeometry* GEOSCoverageSimplifyVW_r	(	GEOSContextHandle_t	extHandle,
		const GEOSGeometry *	input,
		double	tolerance,
		int	preserveBoundary
	)

See also: GEOSCoverageSimplifyVW

◆ GEOSCoverageUnion()

GEOSGeometry* GEOSCoverageUnion ( const GEOSGeometry * g )

Optimized union algorithm for polygonal inputs that are correctly noded and do not overlap. It may generate an error (return NULL) for inputs that do not satisfy this constraint, however this is not guaranteed.

Parameters

g	The input geometry

Returns: A geometry that covers all the points of the input geometry. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 3.8

◆ GEOSCoverageUnion_r()

GEOSGeometry* GEOSCoverageUnion_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSCoverageUnion

◆ GEOSCoveredBy()

char GEOSCoveredBy	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

Tests if geometry g1 is covered by g2, which is the case if every point of g1 lies in g2.

Parameters

g1	Input geometry
g2	Input geometry

Returns: 1 on true, 0 on false, 2 on exception

See also: geos::geom::Geometry::coveredBy

Since: 3.3

◆ GEOSCoveredBy_r()

char GEOSCoveredBy_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

See also: GEOSCoveredBy

◆ GEOSCovers()

char GEOSCovers	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

Tests if geometry g1 covers g2, which is the case if every point of g2 lies in g1.

Parameters

g1	Input geometry
g2	Input geometry

Returns: 1 on true, 0 on false, 2 on exception

See also: geos::geom::Geometry::covers

Since: 3.3

◆ GEOSCovers_r()

char GEOSCovers_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

See also: GEOSCovers

◆ GEOSCrosses()

char GEOSCrosses	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

Tests if two geometries interiors intersect but their boundaries do not. Most useful for finding line crosses cases.

Parameters

g1	Input geometry
g2	Input geometry

Returns: 1 on true, 0 on false, 2 on exception

See also: geos::geom::Geometry::crosses

Since: 2.2

◆ GEOSCrosses_r()

char GEOSCrosses_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

See also: GEOSCrosses

◆ GEOSDelaunayTriangulation()

GEOSGeometry* GEOSDelaunayTriangulation	(	const GEOSGeometry *	g,
		double	tolerance,
		int	onlyEdges
	)

Return a Delaunay triangulation of the vertices of the given geometry.

Parameters

g	the input geometry whose vertices will be used as "sites"
tolerance	optional snapping tolerance to use for improved robustness
onlyEdges	if non-zero will return a MultiLineString, otherwise it will return a GeometryCollection containing triangular Polygons.

Returns: A newly allocated geometry. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 3.4

◆ GEOSDelaunayTriangulation_r()

GEOSGeometry* GEOSDelaunayTriangulation_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double	tolerance,
		int	onlyEdges
	)

See also: GEOSDelaunayTriangulation

◆ GEOSDensify()

GEOSGeometry* GEOSDensify	(	const GEOSGeometry *	g,
		double	tolerance
	)

Densifies a geometry using a given distance tolerance. Additional vertices will be added to every line segment that is greater this tolerance; these vertices will evenly subdivide that segment. Only linear components of input geometry are densified.

Parameters

g	The geometry to densify
tolerance	the distance tolerance to densify

Returns: The densified geometry, or NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 3.10

◆ GEOSDensify_r()

GEOSGeometry* GEOSDensify_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double	tolerance
	)

See also: GEOSDensify

◆ GEOSDifference()

GEOSGeometry* GEOSDifference	(	const GEOSGeometry *	ga,
		const GEOSGeometry *	gb
	)

Returns the difference of two geometries A and B: the set of points that fall within A but not within B.

Parameters

ga	the base geometry
gb	the geometry to subtract from it

Returns: A newly allocated geometry of the difference. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::operation::overlayng::OverlayNG

Since: 2.2

◆ GEOSDifference_r()

GEOSGeometry* GEOSDifference_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

See also: GEOSDifference

◆ GEOSDifferencePrec()

GEOSGeometry* GEOSDifferencePrec	(	const GEOSGeometry *	ga,
		const GEOSGeometry *	gb,
		double	gridSize
	)

Returns the difference of two geometries A and B: the set of points that fall within A but not within B. All the vertices of the output geometry must fall on the grid defined by the gridSize, and the output will be a valid geometry.

Parameters

ga	one of the geometries
gb	the other geometry
gridSize	the cell size of the precision grid

Returns: A newly allocated geometry of the difference. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::operation::overlayng::OverlayNG

Since: 3.9

◆ GEOSDifferencePrec_r()

GEOSGeometry* GEOSDifferencePrec_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		double	gridSize
	)

See also: GEOSDifferencePrec

◆ GEOSDisjoint()

char GEOSDisjoint	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

Tests if two geometries have no point in common.

Parameters

g1	Input geometry
g2	Input geometry

Returns: 1 on true, 0 on false, 2 on exception

See also: geos::geom::Geometry::disjoint

Since: 2.2

◆ GEOSDisjoint_r()

char GEOSDisjoint_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

See also: GEOSDisjoint

◆ GEOSDisjointSubsetUnion()

GEOSGeometry* GEOSDisjointSubsetUnion ( const GEOSGeometry * g )

Optimized union algorithm for inputs that can be divided into subsets that do not intersect. If there is only one such subset, performance can be expected to be worse than GEOSUnionaryUnion.

Parameters

g	The input geometry

Returns: A newly allocated geometry of the union, or NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 3.12

◆ GEOSDisjointSubsetUnion_r()

GEOSGeometry* GEOSDisjointSubsetUnion_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSDisjointSubsetUnion

◆ GEOSDistance()

int GEOSDistance	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		double *	dist
	)

Calculate the distance between two geometries.

Parameters

[in]	g1	Input geometry
[in]	g2	Input geometry
[out]	dist	Pointer to be filled in with distance result

Returns: 1 on success, 0 on exception.

Since: 2.2

◆ GEOSDistance_r()

int GEOSDistance_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		double *	dist
	)

See also: GEOSDistance

◆ GEOSDistanceIndexed()

int GEOSDistanceIndexed	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		double *	dist
	)

Calculate the distance between two geometries, using the indexed facet distance, which first indexes the geometries internally, then calculates the distance. Useful when one or both geometries is very large.

Parameters

[in]	g1	Input geometry
[in]	g2	Input geometry
[out]	dist	Pointer to be filled in with distance result

Returns: 1 on success, 0 on exception.

See also: geos::operation::distance:;IndexedFacetDistance

Since: 3.7

◆ GEOSDistanceIndexed_r()

int GEOSDistanceIndexed_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		double *	dist
	)

See also: GEOSDistanceIndexed

◆ GEOSDistanceWithin()

char GEOSDistanceWithin	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		double	dist
	)

Test whether the distance between two geometries is within the given dist.

Parameters

g1	Input geometry
g2	Input geometry
dist	The max distance

Returns: 1 on true, 0 on false, 2 on exception

Since: 3.10

◆ GEOSDistanceWithin_r()

char GEOSDistanceWithin_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		double	dist
	)

See also: GEOSDistanceWithin

◆ GEOSEnvelope()

GEOSGeometry* GEOSEnvelope ( const GEOSGeometry * g )

Returns minimum rectangular polygon or point that contains the geometry, or an empty point for empty inputs.

Parameters

g	The geometry to calculate an envelope for

Returns: A newly allocated polygonal envelope or point. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 2.2

◆ GEOSEnvelope_r()

GEOSGeometry* GEOSEnvelope_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSEnvelope

◆ GEOSEquals()

char GEOSEquals	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

Tests if two geometries contain the same set of points in the plane.

Parameters

g1	Input geometry
g2	Input geometry

Returns: 1 on true, 0 on false, 2 on exception

See also: geos::geom::Geometry::equals

Since: 2.2

◆ GEOSEquals_r()

char GEOSEquals_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

See also: GEOSEquals

◆ GEOSEqualsExact()

char GEOSEqualsExact	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		double	tolerance
	)

Determine pointwise equality of two geometries, by checking that they have identical structure and that each vertex of g2 is within the distance tolerance of the corresponding vertex in g1. Z and M values are ignored by GEOSEqualsExact, and this function may return true for inputs with different dimensionality. Unlike GEOSEquals(), geometries that are topologically equivalent but have different representations (e.g., LINESTRING (0 0, 1 1) and MULTILINESTRING ((0 0, 1 1)) ) are not considered equal by GEOSEqualsExact().

Parameters

g1	Input geometry
g2	Input geometry
tolerance	Tolerance to determine vertex equality

Returns: 1 on true, 0 on false, 2 on exception

See also: GEOSNormalize()

Since: 3.0

◆ GEOSEqualsExact_r()

char GEOSEqualsExact_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		double	tolerance
	)

See also: GEOSEqualsExact

◆ GEOSEqualsIdentical()

char GEOSEqualsIdentical	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

Determine pointwise equality of two geometries by checking that the structure, ordering, and values of all vertices are identical in all dimensions. NaN values are considered to be equal to other NaN values.

Parameters

g1	Input geometry
g2	Input geometry

Returns: 1 on true, 0 on false, 2 on exception

Since: 3.12

◆ GEOSEqualsIdentical_r()

char GEOSEqualsIdentical_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

See also: GEOSEqualsIdentical

◆ GEOSFrechetDistance()

int GEOSFrechetDistance	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		double *	dist
	)

Calculate the Frechet distance between two geometries, a similarity measure for linear features.

Parameters

[in]	g1	Input geometry
[in]	g2	Input geometry
[out]	dist	Pointer to be filled in with distance result

Returns: 1 on success, 0 on exception.

See also: geos::algorithm::distance::DiscreteFrechetDistance

Since: 3.7

◆ GEOSFrechetDistance_r()

int GEOSFrechetDistance_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		double *	dist
	)

See also: GEOSFrechetDistance

◆ GEOSFrechetDistanceDensify()

int GEOSFrechetDistanceDensify	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		double	densifyFrac,
		double *	dist
	)

Calculate the Frechet distance between two geometries, a similarity measure for linear features. The inputs can be densified to provide a more accurate result.

Parameters

[in]	g1	Input geometry
[in]	g2	Input geometry
[in]	densifyFrac	The largest % of the overall line length that any given two-point segment should be
[out]	dist	Pointer to be filled in with distance result

Returns: 1 on success, 0 on exception.

See also: geos::algorithm::distance::DiscreteFrechetDistance

Since: 3.7

◆ GEOSFrechetDistanceDensify_r()

int GEOSFrechetDistanceDensify_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		double	densifyFrac,
		double *	dist
	)

See also: GEOSFrechetDistanceDensify

◆ GEOSFree()

void GEOSFree ( void * buffer )

Free strings and byte buffers returned by functions such as GEOSWKBWriter_write(), GEOSWKBWriter_writeHEX() and GEOSWKTWriter_write(), etc. If passed a null pointer the function does nothing.

Parameters

buffer The memory to free (may be null)

Since: 3.1

◆ GEOSFree_r()

void GEOSFree_r	(	GEOSContextHandle_t	handle,
		void *	buffer
	)

See also: GEOSFree

◆ GEOSGeoJSONReader_create()

GEOSGeoJSONReader* GEOSGeoJSONReader_create ( void )

Allocate a new GEOSGeoJSONReader.

Returns: a new reader. Caller must free with GEOSGeoJSONReader_destroy()

Since: 3.10

◆ GEOSGeoJSONReader_create_r()

GEOSGeoJSONReader* GEOSGeoJSONReader_create_r ( GEOSContextHandle_t handle )

See also: GEOSGeoJSONReader_create

◆ GEOSGeoJSONReader_destroy()

void GEOSGeoJSONReader_destroy ( GEOSGeoJSONReader * reader )

Free the memory associated with a GEOSGeoJSONReader.

Parameters

reader The reader to destroy.

Since: 3.10

◆ GEOSGeoJSONReader_destroy_r()

void GEOSGeoJSONReader_destroy_r	(	GEOSContextHandle_t	handle,
		GEOSGeoJSONReader *	reader
	)

See also: GEOSGeoJSONReader_destroy

◆ GEOSGeoJSONReader_readGeometry()

GEOSGeometry* GEOSGeoJSONReader_readGeometry	(	GEOSGeoJSONReader *	reader,
		const char *	geojson
	)

Use a reader to parse a GeoJSON string. A single geometry or Feature is parsed as a geometry. A FeatureCollection is parsed as a GeometryCollection. Feature properties are not read.

Parameters

reader	A GeoJSON reader object, caller retains ownership
geojson	The json string to parse, caller retains ownership

Returns: A GEOSGeometry, caller to free with GEOSGeom_destroy())

Since: 3.10

◆ GEOSGeoJSONReader_readGeometry_r()

GEOSGeometry* GEOSGeoJSONReader_readGeometry_r	(	GEOSContextHandle_t	handle,
		GEOSGeoJSONReader *	reader,
		const char *	geojson
	)

See also: GEOSGeoJSONReader_read

◆ GEOSGeoJSONWriter_create()

GEOSGeoJSONWriter* GEOSGeoJSONWriter_create ( void )

Allocate a new GEOSGeoJSONWriter.

Returns: a new writer. Caller must free with GEOSGeoJSONWriter_destroy()

Since: 3.10

◆ GEOSGeoJSONWriter_create_r()

GEOSGeoJSONWriter* GEOSGeoJSONWriter_create_r ( GEOSContextHandle_t handle )

See also: GEOSGeoJSONWriter_create

◆ GEOSGeoJSONWriter_destroy()

void GEOSGeoJSONWriter_destroy ( GEOSGeoJSONWriter * writer )

Free the memory associated with a GEOSGeoJSONWriter.

Parameters

writer The writer to destroy.

Since: 3.10

◆ GEOSGeoJSONWriter_destroy_r()

void GEOSGeoJSONWriter_destroy_r	(	GEOSContextHandle_t	handle,
		GEOSGeoJSONWriter *	writer
	)

See also: GEOSGeoJSONWriter_destroy

◆ GEOSGeoJSONWriter_writeGeometry()

char* GEOSGeoJSONWriter_writeGeometry	(	GEOSGeoJSONWriter *	writer,
		const GEOSGeometry *	g,
		int	indent
	)

Write out the GeoJSON representation of a geometry. Note that writing a GeoJSON Feature or FeatureCollection is unsupported through the GEOS C API.

Parameters

writer	A GeoJSON reader object, caller retains ownership.
g	The geometry to convert, caller retains ownership.
indent	The indentation used. Use -1 for no formatting.

Returns: A char pointer, caller to free with GEOSFree())

Since: 3.10

◆ GEOSGeoJSONWriter_writeGeometry_r()

char* GEOSGeoJSONWriter_writeGeometry_r	(	GEOSContextHandle_t	handle,
		GEOSGeoJSONWriter *	writer,
		const GEOSGeometry *	g,
		int	indent
	)

See also: GEOSGeoJSONWriter_writeGeometry

◆ GEOSGeom_clone()

GEOSGeometry* GEOSGeom_clone ( const GEOSGeometry * g )

Create a new copy of the input geometry.

Parameters

g	The geometry to copy

Returns: A newly allocated geometry. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 2.2

◆ GEOSGeom_clone_r()

GEOSGeometry* GEOSGeom_clone_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSGeom_clone

◆ GEOSGeom_createCircularString()

GEOSGeometry* GEOSGeom_createCircularString ( GEOSCoordSequence * s )

Creates a CircularString geometry.

Parameters

s	Input coordinate sequence, ownership passes to the geometry

Returns: A newly allocated CircularString geometry. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 3.13

◆ GEOSGeom_createCircularString_r()

GEOSGeometry* GEOSGeom_createCircularString_r	(	GEOSContextHandle_t	handle,
		GEOSCoordSequence *	s
	)

See also: GEOSGeom_createCircularString

◆ GEOSGeom_createCollection()

GEOSGeometry* GEOSGeom_createCollection	(	int	type,
		GEOSGeometry **	geoms,
		unsigned int	ngeoms
	)

Create a geometry collection.

Parameters

type	The geometry type, enumerated by GEOSGeomTypes
geoms	A list of geometries that will form the collection
ngeoms	The number of geometries in the geoms list

Returns: A newly allocated geometry collection. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Note: The geoms argument is an array of GEOSGeometry* objects. The caller retains ownership of the containing array, but the ownership of the pointed-to objects is transferred to the returned GEOSGeometry.

Since: 2.2

◆ GEOSGeom_createCollection_r()

GEOSGeometry* GEOSGeom_createCollection_r	(	GEOSContextHandle_t	handle,
		int	type,
		GEOSGeometry **	geoms,
		unsigned int	ngeoms
	)

See also: GEOSGeom_createCollection

◆ GEOSGeom_createCompoundCurve()

GEOSGeometry* GEOSGeom_createCompoundCurve	(	GEOSGeometry **	curves,
		unsigned int	ncurves
	)

Creates a CompoundCurve geometry.

Parameters

curves	A list of geometries that will form the CompoundCurve
ncurves	The number of geometries in the curves list

Returns: A newly allocated CompoundCurve geometry. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 3.13

◆ GEOSGeom_createCompoundCurve_r()

GEOSGeometry* GEOSGeom_createCompoundCurve_r	(	GEOSContextHandle_t	handle,
		GEOSGeometry **	curves,
		unsigned int	ncurves
	)

See also: GEOSGeom_createCompoundCurve

◆ GEOSGeom_createCurvePolygon()

GEOSGeometry* GEOSGeom_createCurvePolygon	(	GEOSGeometry *	shell,
		GEOSGeometry **	holes,
		unsigned int	nholes
	)

Creates a CurvePolygon geometry from ring geometries.

Parameters

shell	A ring that is the exterior ring of the polygon.
holes	An array of rings that are the holes.
nholes	The number of rings in the holes array.

Returns: A newly allocated geometry. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Note: The holes argument is an array of GEOSGeometry* objects. The caller retains ownership of the containing array, but the ownership of the pointed-to objects is transferred to the returned GEOSGeometry.

Since: 3.13

◆ GEOSGeom_createCurvePolygon_r()

GEOSGeometry* GEOSGeom_createCurvePolygon_r	(	GEOSContextHandle_t	handle,
		GEOSGeometry *	shell,
		GEOSGeometry **	holes,
		unsigned int	nholes
	)

See also: GEOSGeom_createCurvePolygon

◆ GEOSGeom_createEmptyCircularString()

GEOSGeometry* GEOSGeom_createEmptyCircularString ( )

Creates an empty CircularString geometry.

Returns: A newly allocated CircularString geometry. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 3.13

◆ GEOSGeom_createEmptyCircularString_r()

GEOSGeometry* GEOSGeom_createEmptyCircularString_r ( GEOSContextHandle_t handle )

See also: GEOSGeom_createEmptyCircularString

◆ GEOSGeom_createEmptyCollection()

GEOSGeometry* GEOSGeom_createEmptyCollection ( int type )

Create an empty geometry collection.

Parameters

type	The geometry type, enumerated by GEOSGeomTypes

Returns: A newly allocated empty geometry collection. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 3.3

◆ GEOSGeom_createEmptyCollection_r()

GEOSGeometry* GEOSGeom_createEmptyCollection_r	(	GEOSContextHandle_t	handle,
		int	type
	)

See also: GEOSGeom_createEmptyCollection

◆ GEOSGeom_createEmptyCompoundCurve()

GEOSGeometry* GEOSGeom_createEmptyCompoundCurve ( )

Creates an empty CompoundCurve geometry.

Returns: A newly allocated CompoundCurve geometry. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 3.13

◆ GEOSGeom_createEmptyCompoundCurve_r()

GEOSGeometry* GEOSGeom_createEmptyCompoundCurve_r ( GEOSContextHandle_t handle )

See also: GEOSGeom_createEmptyCompoundCurve

◆ GEOSGeom_createEmptyCurvePolygon()

GEOSGeometry* GEOSGeom_createEmptyCurvePolygon ( )

Creates an empty CurvePolygon geometry.

Returns: A newly allocated CurvePolygon geometry. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 3.13

◆ GEOSGeom_createEmptyCurvePolygon_r()

GEOSGeometry* GEOSGeom_createEmptyCurvePolygon_r ( GEOSContextHandle_t handle )

See also: GEOSGeom_createEmptyCurvePolygon

◆ GEOSGeom_createEmptyLineString()

GEOSGeometry* GEOSGeom_createEmptyLineString ( void )

Creates an emptylinestring geometry.

Returns: A newly allocated linestring geometry. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 3.3

◆ GEOSGeom_createEmptyLineString_r()

GEOSGeometry* GEOSGeom_createEmptyLineString_r ( GEOSContextHandle_t handle )

See also: GEOSGeom_createEmptyLineString

◆ GEOSGeom_createEmptyPoint()

GEOSGeometry* GEOSGeom_createEmptyPoint ( void )

Creates an empty point.

Returns: A newly allocated empty point geometry. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 3.3

◆ GEOSGeom_createEmptyPoint_r()

GEOSGeometry* GEOSGeom_createEmptyPoint_r ( GEOSContextHandle_t handle )

See also: GEOSGeom_createEmptyPoint

◆ GEOSGeom_createEmptyPolygon()

GEOSGeometry* GEOSGeom_createEmptyPolygon ( void )

Creates an empty polygon geometry.

Returns: A newly allocated empty polygon geometry. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 3.3

◆ GEOSGeom_createEmptyPolygon_r()

GEOSGeometry* GEOSGeom_createEmptyPolygon_r ( GEOSContextHandle_t handle )

See also: GEOSGeom_createEmptyPolygon

◆ GEOSGeom_createLinearRing()

GEOSGeometry* GEOSGeom_createLinearRing ( GEOSCoordSequence * s )

Creates a linear ring geometry, for use in a polygon.

Parameters

s	Input coordinate sequence, ownership passes to the geometry

Returns: A newly allocated linear ring geometry. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 2.2

◆ GEOSGeom_createLinearRing_r()

GEOSGeometry* GEOSGeom_createLinearRing_r	(	GEOSContextHandle_t	handle,
		GEOSCoordSequence *	s
	)

See also: GEOSGeom_createLinearRing

◆ GEOSGeom_createLineString()

GEOSGeometry* GEOSGeom_createLineString ( GEOSCoordSequence * s )

Creates a linestring geometry.

Parameters

s	Input coordinate sequence, ownership passes to the geometry

Returns: A newly allocated linestring geometry. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 2.2

◆ GEOSGeom_createLineString_r()

GEOSGeometry* GEOSGeom_createLineString_r	(	GEOSContextHandle_t	handle,
		GEOSCoordSequence *	s
	)

See also: GEOSGeom_createLineString

◆ GEOSGeom_createPoint()

GEOSGeometry* GEOSGeom_createPoint ( GEOSCoordSequence * s )

Creates a point geometry from a coordinate sequence.

Parameters

s	Input coordinate sequence, ownership passes to the geometry

Returns: A newly allocated point geometry. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 2.2

◆ GEOSGeom_createPoint_r()

GEOSGeometry* GEOSGeom_createPoint_r	(	GEOSContextHandle_t	handle,
		GEOSCoordSequence *	s
	)

See also: GEOSGeom_createPoint

◆ GEOSGeom_createPointFromXY()

GEOSGeometry* GEOSGeom_createPointFromXY	(	double	x,
		double	y
	)

Creates a point geometry from a pair of coordinates.

Parameters

x	The X coordinate
y	The Y coordinate

Returns: A newly allocated point geometry. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 3.8

◆ GEOSGeom_createPointFromXY_r()

GEOSGeometry* GEOSGeom_createPointFromXY_r	(	GEOSContextHandle_t	handle,
		double	x,
		double	y
	)

See also: GEOSGeom_createPointFromXY

◆ GEOSGeom_createPolygon()

GEOSGeometry* GEOSGeom_createPolygon	(	GEOSGeometry *	shell,
		GEOSGeometry **	holes,
		unsigned int	nholes
	)

Creates a polygon geometry from linear ring geometries.

Parameters

shell	A linear ring that is the exterior ring of the polygon.
holes	An array of linear rings that are the holes.
nholes	The number of rings in the holes array.

Returns: A newly allocated geometry. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Note: The holes argument is an array of GEOSGeometry* objects. The caller retains ownership of the containing array, but the ownership of the pointed-to objects is transferred to the returned GEOSGeometry.

Since: 2.2

◆ GEOSGeom_createPolygon_r()

GEOSGeometry* GEOSGeom_createPolygon_r	(	GEOSContextHandle_t	handle,
		GEOSGeometry *	shell,
		GEOSGeometry **	holes,
		unsigned int	nholes
	)

See also: GEOSGeom_createPolygon

◆ GEOSGeom_createRectangle()

GEOSGeometry* GEOSGeom_createRectangle	(	double	xmin,
		double	ymin,
		double	xmax,
		double	ymax
	)

Create a rectangular polygon from bounding coordinates. Will return a point geometry if width and height are 0.

Parameters

xmin	Left bound of envelope
ymin	Lower bound of envelope
xmax	Right bound of envelope
ymax	Upper bound of envelope

Since: 3.11

◆ GEOSGeom_createRectangle_r()

GEOSGeometry* GEOSGeom_createRectangle_r	(	GEOSContextHandle_t	handle,
		double	xmin,
		double	ymin,
		double	xmax,
		double	ymax
	)

See also: GEOSGeom_createRectangle

◆ GEOSGeom_destroy()

void GEOSGeom_destroy ( GEOSGeometry * g )

Release the memory associated with a geometry.

Parameters

g	The geometry to be destroyed.

Since: 2.2

◆ GEOSGeom_destroy_r()

void GEOSGeom_destroy_r	(	GEOSContextHandle_t	handle,
		GEOSGeometry *	g
	)

See also: GEOSGeom_destroy

◆ GEOSGeom_extractUniquePoints()

GEOSGeometry* GEOSGeom_extractUniquePoints ( const GEOSGeometry * g )

Return all distinct vertices of input geometry as a MultiPoint. Note that only 2 dimensions of the vertices are considered when testing for equality.

Parameters

g	The input geometry

Returns: The distinct points Caller is responsible for freeing with GEOSGeom_destroy().

Since: 3.3

◆ GEOSGeom_extractUniquePoints_r()

GEOSGeometry* GEOSGeom_extractUniquePoints_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSGeom_extractUniquePoints

◆ GEOSGeom_getCoordinateDimension()

int GEOSGeom_getCoordinateDimension ( const GEOSGeometry * g )

Return the cartesian dimension of the geometry.

2 for XY data
3 for XYZ data

Parameters

g	Input geometry

Returns: The dimension

Since: 3.3

◆ GEOSGeom_getCoordinateDimension_r()

int GEOSGeom_getCoordinateDimension_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSGeom_getCoordinateDimension

◆ GEOSGeom_getCoordSeq()

const GEOSCoordSequence* GEOSGeom_getCoordSeq ( const GEOSGeometry * g )

Return the coordinate sequence underlying the given geometry (Must be a LineString, LinearRing or Point). Do not directly free the coordinate sequence, it is owned by the parent geometry.

Parameters

g	Input geometry

Returns: Coordinate sequence or NULL on exception.

Since: 2.2

◆ GEOSGeom_getCoordSeq_r()

const GEOSCoordSequence* GEOSGeom_getCoordSeq_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSGeom_getCoordSeq

◆ GEOSGeom_getDimensions()

int GEOSGeom_getDimensions ( const GEOSGeometry * g )

Return the planar dimensionality of the geometry.

0 for point, multipoint
1 for linestring, multilinestring
2 for polygon, multipolygon

See also: geos::geom::Dimension::DimensionType

Parameters

g	Input geometry

Returns: The dimensionality

Since: 2.2

◆ GEOSGeom_getDimensions_r()

int GEOSGeom_getDimensions_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSGeom_getDimensions

◆ GEOSGeom_getExtent()

int GEOSGeom_getExtent	(	const GEOSGeometry *	g,
		double *	xmin,
		double *	ymin,
		double *	xmax,
		double *	ymax
	)

Finds the extent (minimum and maximum X and Y value) of the geometry. Raises an exception for empty geometry input.

Parameters

[in]	g	Input geometry
[out]	xmin	Pointer to place result for minimum X value
[out]	ymin	Pointer to place result for minimum Y value
[out]	xmax	Pointer to place result for maximum X value
[out]	ymax	Pointer to place result for maximum Y value

Returns: 1 on success, 0 on exception

Since: 3.11

◆ GEOSGeom_getExtent_r()

int GEOSGeom_getExtent_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double *	xmin,
		double *	ymin,
		double *	xmax,
		double *	ymax
	)

See also: GEOSGeom_getExtent

◆ GEOSGeom_getPrecision()

double GEOSGeom_getPrecision ( const GEOSGeometry * g )

Read the currently set precision value from the geometry and returns the grid size if it is a fixed precision or 0.0 if it is full floating point precision.

Parameters

g	Input geometry

Returns: The grid size, or -1 on exception

Since: 3.6

◆ GEOSGeom_getPrecision_r()

double GEOSGeom_getPrecision_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSGeom_getPrecision

◆ GEOSGeom_getUserData()

void* GEOSGeom_getUserData ( const GEOSGeometry * g )

Return the anonymous "user data" for this geometry. User data must be managed by the caller, and is not freed when the geometry is destroyed.

Parameters

g	Input geometry

Returns: A void* to the user data, caller is responsible for casting to the appropriate type.

Since: 3.6

◆ GEOSGeom_getUserData_r()

void* GEOSGeom_getUserData_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSGeom_getUserData

◆ GEOSGeom_getXMax()

int GEOSGeom_getXMax	(	const GEOSGeometry *	g,
		double *	value
	)

Finds the maximum X value in the geometry.

Parameters

[in]	g	Input geometry
[out]	value	Pointer to place result

Returns: 0 on exception

Since: 3.7

◆ GEOSGeom_getXMax_r()

int GEOSGeom_getXMax_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double *	value
	)

See also: GEOSGeom_getXMax

◆ GEOSGeom_getXMin()

int GEOSGeom_getXMin	(	const GEOSGeometry *	g,
		double *	value
	)

Finds the minimum X value in the geometry.

Parameters

[in]	g	Input geometry
[out]	value	Pointer to place result

Returns: 0 on exception

Since: 3.7

◆ GEOSGeom_getXMin_r()

int GEOSGeom_getXMin_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double *	value
	)

See also: GEOSGeom_getXMin

◆ GEOSGeom_getYMax()

int GEOSGeom_getYMax	(	const GEOSGeometry *	g,
		double *	value
	)

Finds the maximum Y value in the geometry.

Parameters

[in]	g	Input geometry
[out]	value	Pointer to place result

Returns: 0 on exception

Since: 3.7

◆ GEOSGeom_getYMax_r()

int GEOSGeom_getYMax_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double *	value
	)

See also: GEOSGeom_getYMax

◆ GEOSGeom_getYMin()

int GEOSGeom_getYMin	(	const GEOSGeometry *	g,
		double *	value
	)

Finds the minimum Y value in the geometry.

Parameters

[in]	g	Input geometry
[out]	value	Pointer to place result

Returns: 0 on exception

Since: 3.7

◆ GEOSGeom_getYMin_r()

int GEOSGeom_getYMin_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double *	value
	)

See also: GEOSGeom_getYMin

◆ GEOSGeom_releaseCollection()

GEOSGeometry** GEOSGeom_releaseCollection	(	GEOSGeometry *	collection,
		unsigned int *	ngeoms
	)

Release the sub-geometries of a collection for management. by the caller. The input collection remains as an empty collection, that the caller is responsible for destroying. The output geometries are also the responsibility of the caller, as is the containing array, which must be freed with GEOSFree().

Parameters

collection	The collection that will have its components released.
ngeoms	A pointer to a variable that will be filled with the size of the output array.

Returns: A newly allocated array of GEOSGeometry pointers.

Note: The caller is responsible for freeing the returned array with GEOSFree() and all the elements with GEOSGeom_destroy(). If called with an empty collection, null will be returned and ngeoms set to zero.

Since: 3.12

◆ GEOSGeom_releaseCollection_r()

GEOSGeometry** GEOSGeom_releaseCollection_r	(	GEOSContextHandle_t	handle,
		GEOSGeometry *	collection,
		unsigned int *	ngeoms
	)

See also: GEOSGeom_releaseCollection

◆ GEOSGeom_setPrecision()

GEOSGeometry* GEOSGeom_setPrecision	(	const GEOSGeometry *	g,
		double	gridSize,
		int	flags
	)

Change the coordinate precision of a geometry. This will affect the precision of the existing geometry as well as any geometries derived from this geometry using overlay functions. The output will be a valid GEOSGeometry.

Note that operations will always be performed in the precision of the geometry with higher precision (smaller "gridSize"). That same precision will be attached to the operation outputs.

In the Default and GEOS_PREC_KEEP_COLLAPSED modes invalid input may cause an error to occur, unless the invalidity is below the scale of the requested precision

There are only 3 modes. The GEOS_PREC_NO_TOPO mode takes precedence over GEOS_PREC_KEEP_COLLAPSED. So the combination GEOS_PREC_NO_TOPO || GEOS_PREC_KEEP_COLLAPSED has the same semantics as GEOS_PREC_NO_TOPO

Parameters

g	Input geometry
gridSize	cell size of grid to round coordinates to, or 0 for FLOATING precision
flags	The bitwise OR of members of the GEOSPrecisionRules enum

Returns: The precision reduced result. Caller must free with GEOSGeom_destroy() NULL on exception.

Since: 3.6

◆ GEOSGeom_setPrecision_r()

GEOSGeometry* GEOSGeom_setPrecision_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double	gridSize,
		int	flags
	)

See also: GEOSGeom_setPrecision

◆ GEOSGeom_setUserData()

void GEOSGeom_setUserData	(	GEOSGeometry *	g,
		void *	userData
	)

Set the anonymous "user data" for this geometry.

Parameters

g	Input geometry
userData	Void pointer to user data

Since: 3.6

◆ GEOSGeom_setUserData_r()

void GEOSGeom_setUserData_r	(	GEOSContextHandle_t	handle,
		GEOSGeometry *	g,
		void *	userData
	)

See also: GEOSGeom_setUserData

◆ GEOSGeom_transformXY()

GEOSGeometry* GEOSGeom_transformXY	(	const GEOSGeometry *	g,
		GEOSTransformXYCallback	callback,
		void *	userdata
	)

Apply XY coordinate transform callback to all coordinates in a copy of input geometry. If the callback returns an error, returned geometry will be NULL. Z and M values, if present, are not modified by this function.

Parameters

[in]	g	Input geometry
[in]	callback	a function to be executed for each coordinate in the geometry. The callback takes 3 parameters: x and y coordinate values to be updated and a void userdata pointer.
	userdata	an optional pointer to pe passed to 'callback' as an argument

Returns: a copy of the input geometry with transformed coordinates. Caller must free with GEOSGeom_destroy().

Since: 3.11

◆ GEOSGeom_transformXY_r()

GEOSGeometry* GEOSGeom_transformXY_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		GEOSTransformXYCallback	callback,
		void *	userdata
	)

See also: GEOSGeom_transformXY

◆ GEOSGeom_transformXYZ()

GEOSGeometry* GEOSGeom_transformXYZ	(	const GEOSGeometry *	g,
		GEOSTransformXYZCallback	callback,
		void *	userdata
	)

Apply XYZ coordinate transform callback to all coordinates in a copy of input geometry. If the callback returns an error, returned geometry will be NULL. M values, if present, are not modified by this function.

Parameters

[in]	g	Input geometry
[in]	callback	a function to be executed for each coordinate in the geometry. The callback takes 4 parameters: x, y and z coordinate values to be updated and a void userdata pointer.
	userdata	an optional pointer to pe passed to 'callback' as an argument

Returns: a copy of the input geometry with transformed coordinates. Caller must free with GEOSGeom_destroy().

Since: 3.13

◆ GEOSGeom_transformXYZ_r()

GEOSGeometry* GEOSGeom_transformXYZ_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		GEOSTransformXYZCallback	callback,
		void *	userdata
	)

See also: GEOSGeom_transformXYZ

◆ GEOSGeomFromHEX_buf()

GEOSGeometry* GEOSGeomFromHEX_buf	(	const unsigned char *	hex,
		size_t	size
	)

Deprecated:: use GEOSWKBReader and GEOSWKBWriter_readHEX()

◆ GEOSGeomFromHEX_buf_r()

GEOSGeometry* GEOSGeomFromHEX_buf_r	(	GEOSContextHandle_t	handle,
		const unsigned char *	hex,
		size_t	size
	)

Deprecated:: use GEOSWKBReader and GEOSWKBReader_readHEX_r()

◆ GEOSGeomFromWKB_buf()

GEOSGeometry* GEOSGeomFromWKB_buf	(	const unsigned char *	wkb,
		size_t	size
	)

Deprecated:: use GEOSWKBReader and GEOSWKBWriter_read()

◆ GEOSGeomFromWKB_buf_r()

GEOSGeometry* GEOSGeomFromWKB_buf_r	(	GEOSContextHandle_t	handle,
		const unsigned char *	wkb,
		size_t	size
	)

Deprecated:: use GEOSWKBReader and GEOSWKBReader_read_r()

◆ GEOSGeomFromWKT()

GEOSGeometry* GEOSGeomFromWKT ( const char * wkt )

Deprecated:: use GEOSWKTReader and GEOSWKTReader_read_r()

◆ GEOSGeomFromWKT_r()

GEOSGeometry* GEOSGeomFromWKT_r	(	GEOSContextHandle_t	handle,
		const char *	wkt
	)

Deprecated:: use GEOSWKTReader and GEOSWKTReader_read_r()

◆ GEOSGeomGetEndPoint()

GEOSGeometry* GEOSGeomGetEndPoint ( const GEOSGeometry * g )

Return the last point of a LineString

Parameters

g	Input geometry, must be a LineString

Returns: A Point geometry. Caller must free with GEOSGeom_destroy() NULL on exception.

Since: 3.3

◆ GEOSGeomGetEndPoint_r()

GEOSGeometry* GEOSGeomGetEndPoint_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSGeomGetEndPoint

◆ GEOSGeomGetLength()

int GEOSGeomGetLength	(	const GEOSGeometry *	g,
		double *	length
	)

Calculate the length of a LineString. Only works for LineString inputs, returns exception otherwise.

Parameters

[in]	g	Input geometry
[out]	length	Pointer to be filled in with length result

Returns: 1 on success, 0 on exception.

Since: 3.3

◆ GEOSGeomGetLength_r()

int GEOSGeomGetLength_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double *	length
	)

See also: GEOSGeomGetLength

◆ GEOSGeomGetM()

int GEOSGeomGetM	(	const GEOSGeometry *	g,
		double *	m
	)

Returns the M coordinate, for a Point input, or an exception otherwise.

Parameters

[in]	g	Input Point geometry
[out]	m	Pointer to hold return value

Returns: 1 on success, 0 on exception

Since: 3.12

◆ GEOSGeomGetM_r()

int GEOSGeomGetM_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double *	m
	)

See also: GEOSGeomGetM

◆ GEOSGeomGetNumPoints()

int GEOSGeomGetNumPoints ( const GEOSGeometry * g )

Returns the number of points, for a LineString input, or an exception otherwise.

Parameters

g	Input LineString geometry

Returns: Number of points, -1 on exception

Since: 2.2

◆ GEOSGeomGetNumPoints_r()

int GEOSGeomGetNumPoints_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSGeomGetNumPoints

◆ GEOSGeomGetPointN()

GEOSGeometry* GEOSGeomGetPointN	(	const GEOSGeometry *	g,
		int	n
	)

Return the N'th point of a LineString

Parameters

g	Input geometry, must be a LineString
n	Index of desired point (zero based)

Returns: A Point geometry. Caller must free with GEOSGeom_destroy() NULL on exception.

Since: 3.3

◆ GEOSGeomGetPointN_r()

GEOSGeometry* GEOSGeomGetPointN_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		int	n
	)

See also: GEOSGeomGetPointN

◆ GEOSGeomGetStartPoint()

GEOSGeometry* GEOSGeomGetStartPoint ( const GEOSGeometry * g )

Return the first point of a LineString

Parameters

g	Input geometry, must be a LineString

Returns: A Point geometry. Caller must free with GEOSGeom_destroy() NULL on exception.

Since: 3.3

◆ GEOSGeomGetStartPoint_r()

GEOSGeometry* GEOSGeomGetStartPoint_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSGeomGetStartPoint

◆ GEOSGeomGetX()

int GEOSGeomGetX	(	const GEOSGeometry *	g,
		double *	x
	)

Returns the X coordinate, for a Point input, or an exception otherwise.

Parameters

[in]	g	Input Point geometry
[out]	x	Pointer to hold return value

Returns: 1 on success, 0 on exception

Since: 2.2

◆ GEOSGeomGetX_r()

int GEOSGeomGetX_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double *	x
	)

See also: GEOSGeomGetX

◆ GEOSGeomGetY()

int GEOSGeomGetY	(	const GEOSGeometry *	g,
		double *	y
	)

Returns the Y coordinate, for a Point input, or an exception otherwise.

Parameters

[in]	g	Input Point geometry
[out]	y	Pointer to hold return value

Returns: 1 on success, 0 on exception

Since: 2.2

◆ GEOSGeomGetY_r()

int GEOSGeomGetY_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double *	y
	)

See also: GEOSGeomGetY

◆ GEOSGeomGetZ()

int GEOSGeomGetZ	(	const GEOSGeometry *	g,
		double *	z
	)

Returns the Z coordinate, for a Point input, or an exception otherwise.

Parameters

[in]	g	Input Point geometry
[out]	z	Pointer to hold return value

Returns: 1 on success, 0 on exception

Since: 3.7

◆ GEOSGeomGetZ_r()

int GEOSGeomGetZ_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double *	z
	)

See also: GEOSGeomGetZ

◆ GEOSGeomToHEX_buf()

unsigned char* GEOSGeomToHEX_buf	(	const GEOSGeometry *	g,
		size_t *	size
	)

Deprecated:: use GEOSWKBWriter and GEOSWKBWriter_writeHEX()

◆ GEOSGeomToHEX_buf_r()

unsigned char* GEOSGeomToHEX_buf_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		size_t *	size
	)

Deprecated:: use GEOSWKBWriter and GEOSWKBWriter_writeHEX_r()

◆ GEOSGeomToWKB_buf()

unsigned char* GEOSGeomToWKB_buf	(	const GEOSGeometry *	g,
		size_t *	size
	)

Deprecated:: use GEOSWKBWriter and GEOSWKBWriter_write()

◆ GEOSGeomToWKB_buf_r()

unsigned char* GEOSGeomToWKB_buf_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		size_t *	size
	)

Deprecated:: use GEOSWKBWriter and GEOSWKBWriter_write_r()

◆ GEOSGeomToWKT()

char* GEOSGeomToWKT ( const GEOSGeometry * g )

Deprecated:: use GEOSWKTWriter and GEOSWKTWriter_write()

◆ GEOSGeomToWKT_r()

char* GEOSGeomToWKT_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

Deprecated:: use GEOSWKTWriter and GEOSWKTWriter_write_r()

◆ GEOSGeomType()

char* GEOSGeomType ( const GEOSGeometry * g )

Returns the geometry type string for this geometry. eg: "GeometryCollection", "LineString"

Parameters

g	Input geometry

Returns: A string with the geometry type. Caller must free with GEOSFree(). NULL on exception.

Since: 2.2

◆ GEOSGeomType_r()

char* GEOSGeomType_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSGeomType

◆ GEOSGeomTypeId()

int GEOSGeomTypeId ( const GEOSGeometry * g )

Returns the GEOSGeomTypeId number for this geometry.

Parameters

g	Input geometry

Returns: The geometry type number, or -1 on exception.

Since: 2.2

◆ GEOSGeomTypeId_r()

int GEOSGeomTypeId_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSGeomTypeId

◆ GEOSGetCentroid()

GEOSGeometry* GEOSGetCentroid ( const GEOSGeometry * g )

Returns a point at the center of mass of the input.

Parameters

g	The input geometry

Returns: A point at the center of mass of the input Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::algorithm::Centroid

Since: 2.2

◆ GEOSGetCentroid_r()

GEOSGeometry* GEOSGetCentroid_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSGetCentroid

◆ GEOSGetExteriorRing()

const GEOSGeometry* GEOSGetExteriorRing ( const GEOSGeometry * g )

Get the external ring of a Polygon.

Note: Returned object is a pointer to internal storage: it must NOT be destroyed directly.

Parameters

g	Input Polygon geometry

Returns: LinearRing geometry. Owned by parent geometry, do not free. NULL on exception.

Since: 2.2

◆ GEOSGetExteriorRing_r()

const GEOSGeometry* GEOSGetExteriorRing_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSGetExteriorRing

◆ GEOSGetGeometryN()

const GEOSGeometry* GEOSGetGeometryN	(	const GEOSGeometry *	g,
		int	n
	)

Returns the specified sub-geometry of a collection. For a simple geometry, returns a pointer to the input. Returned object is a pointer to internal storage: it must NOT be destroyed directly.

Parameters

g	Input geometry
n	Sub-geometry index, zero-based

Returns: A const GEOSGeometry, do not free! It will be freed when the parent is freed. Returns NULL on exception.

Note: Up to GEOS 3.2.0 the input geometry must be a Collection, in later versions it doesn't matter (getGeometryN(0) for a single will return the input).

Since: 2.2

◆ GEOSGetGeometryN_r()

const GEOSGeometry* GEOSGetGeometryN_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		int	n
	)

See also: GEOSGetGeometryN

◆ GEOSGetInteriorRingN()

const GEOSGeometry* GEOSGetInteriorRingN	(	const GEOSGeometry *	g,
		int	n
	)

Returns the N'th ring for a Polygon input.

Note: Returned object is a pointer to internal storage: it must NOT be destroyed directly.

Parameters

g	Input Polygon geometry
n	Index of the desired ring

Returns: LinearRing geometry. Owned by parent geometry, do not free. NULL on exception.

Since: 2.2

◆ GEOSGetInteriorRingN_r()

const GEOSGeometry* GEOSGetInteriorRingN_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		int	n
	)

See also: GEOSGetInteriorRingN

◆ GEOSGetNumCoordinates()

int GEOSGetNumCoordinates ( const GEOSGeometry * g )

Get the total number of points in a geometry, of any type.

Parameters

g	Input geometry

Returns: Number of points in the geometry. -1 on exception.

Since: 2.2

◆ GEOSGetNumCoordinates_r()

int GEOSGetNumCoordinates_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSGetNumCoordinates

◆ GEOSGetNumGeometries()

int GEOSGetNumGeometries ( const GEOSGeometry * g )

Returns the number of sub-geometries immediately under a multi-geometry or collection or 1 for a simple geometry. For nested collections, remember to check if returned sub-geometries are themselves also collections. Empty collection or multi-geometry types return 0, and empty simple geometry types return 1.

Parameters

g	Input geometry

Returns: Number of direct children in this collection

Warning: For GEOS < 3.2 this function may crash when fed simple geometries

Since: 2.2

◆ GEOSGetNumGeometries_r()

int GEOSGetNumGeometries_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSGetNumGeometries

◆ GEOSGetNumInteriorRings()

int GEOSGetNumInteriorRings ( const GEOSGeometry * g )

Returns the number of interior rings, for a Polygon input, or an exception otherwise.

Parameters

g	Input Polygon geometry

Returns: Number of interior rings, -1 on exception

Since: 2.2

◆ GEOSGetNumInteriorRings_r()

int GEOSGetNumInteriorRings_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSGetNumInteriorRings

◆ GEOSGetSRID()

int GEOSGetSRID ( const GEOSGeometry * g )

Returns the "spatial reference id" (SRID) for this geometry.

Parameters

g	Input geometry

Returns: SRID number or 0 if unknown / not set.

Since: 2.2

◆ GEOSGetSRID_r()

int GEOSGetSRID_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSGetSRID

◆ GEOSHasM()

char GEOSHasM ( const GEOSGeometry * g )

Tests whether the input geometry has M coordinates.

Parameters

g	The geometry to test

Returns: 1 on true, 0 on false, 2 on exception

Since: 3.12

◆ GEOSHasM_r()

char GEOSHasM_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSHasM

◆ GEOSHasZ()

char GEOSHasZ ( const GEOSGeometry * g )

Tests whether the input geometry has Z coordinates.

Parameters

g	The geometry to test

Returns: 1 on true, 0 on false, 2 on exception

Since: 2.2

◆ GEOSHasZ_r()

char GEOSHasZ_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSHasZ

◆ GEOSHausdorffDistance()

int GEOSHausdorffDistance	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		double *	dist
	)

Calculate the Hausdorff distance between two geometries. Hausdorff distance is the largest distance between two geometries.

Parameters

[in]	g1	Input geometry
[in]	g2	Input geometry
[out]	dist	Pointer to be filled in with distance result

Returns: 1 on success, 0 on exception.

See also: geos::algorithm::distance::DiscreteHausdorffDistance

Since: 3.2

◆ GEOSHausdorffDistance_r()

int GEOSHausdorffDistance_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		double *	dist
	)

See also: GEOSHausdorffDistance

◆ GEOSHausdorffDistanceDensify()

int GEOSHausdorffDistanceDensify	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		double	densifyFrac,
		double *	dist
	)

Calculate a more precise Hausdorff distance between two geometries, by densifying the inputs before computation. Hausdorff distance is the largest distance between two geometries.

Parameters

[in]	g1	Input geometry
[in]	g2	Input geometry
[in]	densifyFrac	The largest % of the overall line length that any given two-point segment should be
[out]	dist	Pointer to be filled in with distance result

Returns: 1 on success, 0 on exception.

See also: geos::algorithm::distance::DiscreteHausdorffDistance

Since: 3.2

◆ GEOSHausdorffDistanceDensify_r()

int GEOSHausdorffDistanceDensify_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		double	densifyFrac,
		double *	dist
	)

See also: GEOSHausdorffDistanceDensify

◆ GEOSHilbertCode()

int GEOSHilbertCode	(	const GEOSGeometry *	geom,
		const GEOSGeometry *	extent,
		unsigned int	level,
		unsigned int *	code
	)

Calculate the Hilbert code of the centroid of a geometry relative to an extent. This allows sorting geometries in a deterministic way, such that similar Hilbert codes are likely to be near each other in two-dimensional space. The caller must ensure that the geometry is contained within the extent.

Parameters

[in]	geom	Input geometry, must be non-empty
[in]	extent	Extent within which to calculate the Hilbert code for geom
[in]	level	The level of precision of the Hilbert curve, up to 16
[out]	code	Pointer to be filled in with Hilbert code result

Returns: 1 on success, 0 on exception.

Since: 3.11

◆ GEOSHilbertCode_r()

int GEOSHilbertCode_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	geom,
		const GEOSGeometry *	extent,
		unsigned int	level,
		unsigned int *	code
	)

See also: GEOSHilbertCode

◆ GEOSInterpolate()

GEOSGeometry* GEOSInterpolate	(	const GEOSGeometry *	line,
		double	d
	)

Measuring from start of line, return point that is distance the start. Line parameter must be a LineString. The returned point is not guaranteed to intersect the line due to limitations of floating point calculations.

Parameters

line	linear target of projection
d	distance from start of line to created point

Returns: The point GEOSGeometry that is distance from the start of line. Caller takes ownership of returned geometry.

Since: 3.2

◆ GEOSInterpolate_r()

GEOSGeometry* GEOSInterpolate_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	line,
		double	d
	)

See also: GEOSInterpolate

◆ GEOSInterpolateNormalized()

GEOSGeometry* GEOSInterpolateNormalized	(	const GEOSGeometry *	line,
		double	proportion
	)

Measuring from start of line, return point that is a proportion the start. Line parameter must be a LineString.

Parameters

line	linear target of projection
proportion	The proportion from the start of line to created point

Returns: The point GEOSGeometry that is distance from the start of line. Caller takes ownership of returned geometry.

Since: 3.2

◆ GEOSInterpolateNormalized_r()

GEOSGeometry* GEOSInterpolateNormalized_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double	d
	)

See also: GEOSInterpolateNormalized

◆ GEOSIntersection()

GEOSGeometry* GEOSIntersection	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

Returns the intersection of two geometries: the set of points that fall within both geometries.

Parameters

g1	one of the geometries
g2	the other geometry

Returns: A newly allocated geometry of the intersection. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::operation::overlayng::OverlayNG

Since: 2.2

◆ GEOSIntersection_r()

GEOSGeometry* GEOSIntersection_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

See also: GEOSIntersection

◆ GEOSIntersectionPrec()

GEOSGeometry* GEOSIntersectionPrec	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		double	gridSize
	)

Returns the intersection of two geometries: the set of points that fall within both geometries. All the vertices of the output geometry must fall on the grid defined by the gridSize, and the output will be a valid geometry.

Parameters

g1	one of the geometries
g2	the other geometry
gridSize	the cell size of the precision grid

Returns: A newly allocated geometry of the intersection. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::operation::overlayng::OverlayNG

Since: 3.9

◆ GEOSIntersectionPrec_r()

GEOSGeometry* GEOSIntersectionPrec_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		double	gridSize
	)

See also: GEOSIntersectionPrec

◆ GEOSIntersects()

char GEOSIntersects	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

Tests if two geometries intersect.

Parameters

g1	Input geometry
g2	Input geometry

Returns: 1 on true, 0 on false, 2 on exception

See also: geos::geom::Geometry::intersects

Since: 2.2

◆ GEOSIntersects_r()

char GEOSIntersects_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

See also: GEOSIntersects

◆ GEOSisClosed()

char GEOSisClosed ( const GEOSGeometry * g )

Tests whether the input geometry is closed. A closed geometry is a linestring or multilinestring with the start and end points being the same.

Parameters

g	The geometry to test

Returns: 1 on true, 0 on false, 2 on exception

Since: 3.3

◆ GEOSisClosed_r()

char GEOSisClosed_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSisClosed

◆ GEOSisEmpty()

char GEOSisEmpty ( const GEOSGeometry * g )

Tests whether the input geometry is empty. If the geometry or any component is non-empty, the geometry is non-empty. An empty geometry has no boundary or interior.

Parameters

g	The geometry to test

Returns: 1 on true, 0 on false, 2 on exception

Since: 2.2

◆ GEOSisEmpty_r()

char GEOSisEmpty_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSisEmpty

◆ GEOSisRing()

char GEOSisRing ( const GEOSGeometry * g )

Tests whether the input geometry is a ring. Rings are linestrings, without self-intersections, with start and end point being identical.

Parameters

g	The geometry to test

Returns: 1 on true, 0 on false, 2 on exception

Since: 2.2

◆ GEOSisRing_r()

char GEOSisRing_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSisRing

◆ GEOSisSimple()

char GEOSisSimple ( const GEOSGeometry * g )

Tests whether the input geometry is "simple". Mostly relevant for linestrings. A "simple" linestring has no self-intersections.

Parameters

g	The geometry to test

Returns: 1 on true, 0 on false, 2 on exception

Since: 2.2

◆ GEOSisSimple_r()

char GEOSisSimple_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSisSimple

◆ GEOSisValid()

char GEOSisValid ( const GEOSGeometry * g )

Check the validity of the provided geometry.

All points are valid.
All non-zero-length linestrings are valid.
Polygon rings must be non-self-intersecting, and interior rings contained within exterior rings.
Multi-polygon components may not touch or overlap.

Parameters

g	The geometry to test

Returns: 1 on true, 0 on false, 2 on exception

See also: geos::operation::valid::isValidOp

Since: 2.2

◆ GEOSisValid_r()

char GEOSisValid_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSisValid

◆ GEOSisValidDetail()

char GEOSisValidDetail	(	const GEOSGeometry *	g,
		int	flags,
		char **	reason,
		GEOSGeometry **	location
	)

In one step, calculate and return the validity, the human readable validity reason and a point at which validity rules are broken. Caller has the responsibility to destroy 'reason' with GEOSFree() and 'location' with GEOSGeom_destroy()

Parameters

g	The geometry to test
flags	A value from the GEOSValidFlags enum
reason	A pointer in which the reason string will be places
location	A pointer in which the location GEOSGeometry will be placed

Returns: 1 when valid, 0 when invalid, 2 on exception

Since: 3.3

◆ GEOSisValidDetail_r()

char GEOSisValidDetail_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		int	flags,
		char **	reason,
		GEOSGeometry **	location
	)

See also: GEOSisValidDetail

◆ GEOSisValidReason()

char* GEOSisValidReason ( const GEOSGeometry * g )

Return the human readable reason a geometry is invalid, "Valid Geometry" string otherwise, or NULL on exception.

Parameters

g	The geometry to test

Returns: A string with the reason, NULL on exception. Caller must GEOSFree() their result.

Since: 3.1

◆ GEOSisValidReason_r()

char* GEOSisValidReason_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSisValidReason

◆ GEOSLargestEmptyCircle()

GEOSGeometry* GEOSLargestEmptyCircle	(	const GEOSGeometry *	obstacles,
		const GEOSGeometry *	boundary,
		double	tolerance
	)

Constructs the "largest empty circle" (LEC) for a set of obstacle geometries and within a polygonal boundary, with accuracy to to a specified distance tolerance. The obstacles may be any collection of points, lines and polygons. The LEC is the largest circle whose interior does not intersect with any obstacle. and which has its center inside the given boundary. If no boundary is provided, the convex hull of the obstacles is used. The LEC center is the point in the interior of the boundary which has the farthest distance from the obstacles (up to the given distance tolerance). The LEC is determined by the center point and a point indicating the circle radius (which will lie on an obstacle).
To compute an LEC which lies wholly within a polygonal boundary, include the boundary of the polygon(s) as a linear obstacle.
The implementation uses a successive-approximation technique over a grid of square cells covering the obstacles and boundary. The grid is refined using a branch-and-bound algorithm. Point containment and distance are computed in a performant way by using spatial indexes.
Returns the LEC radius as a two-point linestring, with the start point at the center of the inscribed circle and the end on the boundary of the circle.

Parameters

obstacles	The geometries that the LEC must not cross
boundary	The area to contain the LEC center (may be null or empty)
tolerance	Stop the algorithm when the search area is smaller than this tolerance

Returns: A newly allocated geometry of the LEC radius line. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::algorithm::construct::LargestEmptyCircle

Since: 3.9

◆ GEOSLargestEmptyCircle_r()

GEOSGeometry* GEOSLargestEmptyCircle_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		const GEOSGeometry *	boundary,
		double	tolerance
	)

See also: GEOSLargestEmptyCircle

◆ GEOSLength()

int GEOSLength	(	const GEOSGeometry *	g,
		double *	length
	)

Calculate the length of a geometry.

Parameters

[in]	g	Input geometry
[out]	length	Pointer to be filled in with length result

Returns: 1 on success, 0 on exception.

Since: 2.2

◆ GEOSLength_r()

int GEOSLength_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double *	length
	)

See also: GEOSLength

◆ GEOSLineMerge()

GEOSGeometry* GEOSLineMerge ( const GEOSGeometry * g )

Merges a set of LineStrings, joining them at nodes which have cardinality 2. Lines may have their direction reversed.

Parameters

g	The input linework

Returns: The merged linework. Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::operation::linemerge::LineMerger

Since: 2.2

◆ GEOSLineMerge_r()

GEOSGeometry* GEOSLineMerge_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSLineMerge

◆ GEOSLineMergeDirected()

GEOSGeometry* GEOSLineMergeDirected ( const GEOSGeometry * g )

Merges a set of LineStrings, joining them at nodes which have cardinality 2. and where the lines have the same direction. This means that lines do not have their direction reversed.

Parameters

g	The input linework

Returns: The merged linework. Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::operation::linemerge::LineMerger

Since: 3.11

◆ GEOSLineMergeDirected_r()

GEOSGeometry* GEOSLineMergeDirected_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSLineMergeDirected

◆ GEOSLineSubstring()

GEOSGeometry* GEOSLineSubstring	(	const GEOSGeometry *	g,
		double	start_fraction,
		double	end_fraction
	)

Computes the line which is the section of the input LineString starting and ending at the given length fractions.

Parameters

g	The input LineString
start_fraction	start fraction (0-1) along the length of g
end_fraction	end fraction (0-1) along the length of g

Returns: selected substring. Caller is responsible for freeing with GEOSGeom_destroy()

Since: 3.12

◆ GEOSLineSubstring_r()

GEOSGeometry* GEOSLineSubstring_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double	start_fraction,
		double	end_fdraction
	)

See also: GEOSLineSubstring

◆ GEOSMakeValid()

GEOSGeometry* GEOSMakeValid ( const GEOSGeometry * g )

Repair an invalid geometry, returning a valid output.

Parameters

g	The geometry to repair

Returns: The repaired geometry. Caller must free with GEOSGeom_destroy().

Since: 3.8

◆ GEOSMakeValid_r()

GEOSGeometry* GEOSMakeValid_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSMakeValid

◆ GEOSMakeValidParams_create()

GEOSMakeValidParams* GEOSMakeValidParams_create ( void )

Create a GEOSMakeValidParams to hold the desired parameters to control the algorithm and behavior of the validation process.

Returns: a parameter object

See also: GEOSMakeValidWithParams

Since: 3.10

◆ GEOSMakeValidParams_create_r()

GEOSMakeValidParams* GEOSMakeValidParams_create_r ( GEOSContextHandle_t extHandle )

See also: GEOSMakeValidParams_create

◆ GEOSMakeValidParams_destroy()

void GEOSMakeValidParams_destroy ( GEOSMakeValidParams * parms )

Destroy a GEOSMakeValidParams.

Parameters

parms the object to destroy

See also: GEOSMakeValidWithParams

Since: 3.10

◆ GEOSMakeValidParams_destroy_r()

void GEOSMakeValidParams_destroy_r	(	GEOSContextHandle_t	handle,
		GEOSMakeValidParams *	parms
	)

See also: GEOSMakeValidParams_destroy

◆ GEOSMakeValidParams_setKeepCollapsed()

int GEOSMakeValidParams_setKeepCollapsed	(	GEOSMakeValidParams *	p,
		int	keepCollapsed
	)

When this parameter is nn-zero, the GEOS_MAKE_VALID_STRUCTURE method will keep components that have collapsed into a lower dimensionality. For example, a ring collapsing to a line, or a line collapsing to a point.

Returns: 0 on exception, 1 on success.

See also: GEOSMakeValidWithParams

Since: 3.10

◆ GEOSMakeValidParams_setKeepCollapsed_r()

int GEOSMakeValidParams_setKeepCollapsed_r	(	GEOSContextHandle_t	handle,
		GEOSMakeValidParams *	p,
		int	style
	)

See also: GEOSMakeValidParams_setKeepCollapsed

◆ GEOSMakeValidParams_setMethod()

int GEOSMakeValidParams_setMethod	(	GEOSMakeValidParams *	p,
		enum GEOSMakeValidMethods	method
	)

Set the GEOSMakeValidMethods to use in making the geometry valid.

Returns: 0 on exception, 1 on success.

See also: GEOSMakeValidWithParams

Since: 3.10

◆ GEOSMakeValidParams_setMethod_r()

int GEOSMakeValidParams_setMethod_r	(	GEOSContextHandle_t	handle,
		GEOSMakeValidParams *	p,
		enum GEOSMakeValidMethods	method
	)

See also: GEOSMakeValidParams_setMethod

◆ GEOSMakeValidWithParams()

GEOSGeometry* GEOSMakeValidWithParams	(	const GEOSGeometry *	g,
		const GEOSMakeValidParams *	makeValidParams
	)

Repair an invalid geometry, returning a valid output, using the indicated GEOSMakeValidMethods algorithm and options.

Parameters

g	is the geometry to test.
makeValidParams	is a GEOSMakeValidParams with the desired parameters set on it.

Returns: A repaired geometry. Caller must free with GEOSGeom_destroy().

See also: GEOSMakeValidParams_create; GEOSMakeValidParams_destroy; GEOSMakeValidParams_setMethod; GEOSMakeValidParams_setKeepCollapsed

Since: 3.10

◆ GEOSMakeValidWithParams_r()

GEOSGeometry* GEOSMakeValidWithParams_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		const GEOSMakeValidParams *	makeValidParams
	)

See also: GEOSMakeValidWithParams

◆ GEOSMaximumInscribedCircle()

GEOSGeometry* GEOSMaximumInscribedCircle	(	const GEOSGeometry *	g,
		double	tolerance
	)

Constructs the "maximum inscribed circle" (MIC) for a polygonal geometry, up to a specified tolerance. The MIC is determined by a point in the interior of the area which has the farthest distance from the area boundary, along with a boundary point at that distance. In the context of geography the center of the MIC is known as the "pole of inaccessibility". A cartographic use case is to determine a suitable point to place a map label within a polygon. The radius length of the MIC is a measure of how "narrow" a polygon is. It is the distance at which the negative buffer becomes empty. The class supports polygons with holes and multipolygons. The implementation uses a successive-approximation technique over a grid of square cells covering the area geometry. The grid is refined using a branch-and-bound algorithm. Point containment and distance are computed in a performant way by using spatial indexes. Returns a two-point linestring, with one point at the center of the inscribed circle and the other on the boundary of the inscribed circle.

Parameters

g	Input geometry
tolerance	Stop the algorithm when the search area is smaller than this tolerance

Returns: A newly allocated geometry of the MIC. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::algorithm::construct::MaximumInscribedCircle

Since: 3.9

◆ GEOSMaximumInscribedCircle_r()

GEOSGeometry* GEOSMaximumInscribedCircle_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double	tolerance
	)

See also: GEOSMaximumInscribedCircle

◆ GEOSMinimumBoundingCircle()

GEOSGeometry* GEOSMinimumBoundingCircle	(	const GEOSGeometry *	g,
		double *	radius,
		GEOSGeometry **	center
	)

Returns a geometry which represents the "minimum bounding circle", the smallest circle that contains the input.

Parameters

[in]	g	The input geometry
[out]	radius	Pointer will be filled with output radius.
[out]	center	Pointer will be filled with output circle center. Caller must free.

Returns: The circle geometry or NULL on exception Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::algorithm::MinimumBoundingCircle::getCircle

Since: 3.8

◆ GEOSMinimumBoundingCircle_r()

GEOSGeometry* GEOSMinimumBoundingCircle_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double *	radius,
		GEOSGeometry **	center
	)

See also: GEOSMinimumBoundingCircle

◆ GEOSMinimumClearance()

int GEOSMinimumClearance	(	const GEOSGeometry *	g,
		double *	d
	)

Computes the minimum clearance of a geometry. The minimum clearance is the smallest amount by which a vertex could be move to produce an invalid polygon, a non-simple linestring, or a multipoint with repeated points. If a geometry has a minimum clearance of 'eps', it can be said that:

No two distinct vertices in the geometry are separated by less than 'eps'
No vertex is closer than 'eps' to a line segment of which it is not an endpoint.

If the minimum clearance cannot be defined for a geometry (such as with a single point, or a multipoint whose points are identical, a value of Infinity will be calculated.

Parameters

g	the input geometry
d	a double to which the result can be stored

Returns: 0 if no exception occurred. 2 if an exception occurred.

See also: geos::precision::MinimumClearance

Since: 3.6

◆ GEOSMinimumClearance_r()

int GEOSMinimumClearance_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double *	distance
	)

See also: GEOSMinimumClearance

◆ GEOSMinimumClearanceLine()

GEOSGeometry* GEOSMinimumClearanceLine ( const GEOSGeometry * g )

Returns a LineString whose endpoints define the minimum clearance of a geometry. If the geometry has no minimum clearance, an empty LineString will be returned.

Parameters

g	the input geometry

Returns: a linestring geometry, or NULL if an exception occurred. Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::precision::MinimumClearance

Since: 3.6

◆ GEOSMinimumClearanceLine_r()

GEOSGeometry* GEOSMinimumClearanceLine_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSMinimumClearanceLine

◆ GEOSMinimumRotatedRectangle()

GEOSGeometry* GEOSMinimumRotatedRectangle ( const GEOSGeometry * g )

Returns the minimum rotated rectangular POLYGON which encloses the input geometry. The rectangle has width equal to the minimum diameter, and a longer length. If the convex hill of the input is degenerate (a line or point) a linestring or point is returned. The minimum rotated rectangle can be used as an extremely generalized representation for the given geometry.

Parameters

g	The input geometry

Returns: A newly allocated geometry of the rotated envelope. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

Since: 3.6

◆ GEOSMinimumRotatedRectangle_r()

GEOSGeometry* GEOSMinimumRotatedRectangle_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSMinimumRotatedRectangle

◆ GEOSMinimumWidth()

GEOSGeometry* GEOSMinimumWidth ( const GEOSGeometry * g )

Returns a linestring geometry which represents the minimum diameter of the geometry. The minimum diameter is defined to be the width of the smallest band that contains the geometry, where a band is a strip of the plane defined by two parallel lines. This can be thought of as the smallest hole that the geometry can be moved through, with a single rotation.

Parameters

g	The input geometry

Returns: A newly allocated geometry of the LEC. NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::algorithm::MinimumDiameter

Since: 3.6

◆ GEOSMinimumWidth_r()

GEOSGeometry* GEOSMinimumWidth_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSMinimumWidth

◆ GEOSNearestPoints()

GEOSCoordSequence* GEOSNearestPoints	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

The closest points of the two geometries. The first point comes from g1 geometry and the second point comes from g2.

Parameters

[in]	g1	Input geometry
[in]	g2	Input geometry

Returns: A coordinate sequence with the two points, or NULL on exception. Caller must free with GEOSCoordSeq_destroy().

Since: 3.5

◆ GEOSNearestPoints_r()

GEOSCoordSequence* GEOSNearestPoints_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

See also: GEOSNearestPoints

◆ GEOSNode()

GEOSGeometry* GEOSNode ( const GEOSGeometry * g )

For linear inputs, returns a new geometry in which no lines cross each other, and all touching occurs at end points.

Parameters

g	The input geometry

Returns: The noded geometry or NULL on exception Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::noding::GeometryNoder::node

Since: 3.4

◆ GEOSNode_r()

GEOSGeometry* GEOSNode_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSNode

◆ GEOSNormalize()

int GEOSNormalize ( GEOSGeometry * g )

Organize the elements, rings, and coordinate order of geometries in a consistent way, so that geometries that represent the same object can be easily compared. Modifies the geometry in-place.

Normalization ensures the following:

Lines are oriented to have smallest coordinate first (apart from duplicate endpoints)
Rings start with their smallest coordinate (using XY ordering)
Polygon shell rings are oriented CW, and holes CCW
Collection elements are sorted by their first coordinate

Use before calling GEOSEqualsExact to avoid false "not equal" results.

Parameters

g	Input geometry

Returns: 0 on success or -1 on exception

Since: 3.0

◆ GEOSNormalize_r()

int GEOSNormalize_r	(	GEOSContextHandle_t	handle,
		GEOSGeometry *	g
	)

See also: GEOSNormalize

◆ GEOSOffsetCurve()

GEOSGeometry* GEOSOffsetCurve	(	const GEOSGeometry *	g,
		double	width,
		int	quadsegs,
		int	joinStyle,
		double	mitreLimit
	)

Generates offset curve line(s) for a geometry. Handles all geometry types as input.

For a LineString the result is a LineString.
For a Point the result is an empty LineString.
For a Polygon the result is the boundary lines(s) of the polygon buffered to the offset distance (which may be a MultiLineString).

For a collection the result is a collection of the element offset curves.

Parameters

g	The linear geometry to offset from
width	Distance to offset from the curve. Negative for a right-side offset. Positive for a left-side offset.
quadsegs	Number of segments per quadrant
joinStyle	See GEOSBufJoinStyles
mitreLimit	See GEOSBufferParams_setMitreLimit

Returns: The offset geometry. Returns NULL on exception. Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::operation::buffer::BufferBuilder::bufferLineSingleSided

Since: 3.3

◆ GEOSOffsetCurve_r()

GEOSGeometry* GEOSOffsetCurve_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		double	width,
		int	quadsegs,
		int	joinStyle,
		double	mitreLimit
	)

See also: GEOSOffsetCurve

◆ GEOSOrientationIndex()

int GEOSOrientationIndex	(	double	Ax,
		double	Ay,
		double	Bx,
		double	By,
		double	Px,
		double	Py
	)

For the points formed by the six input ordinates, walking from A to B and then to P.

Parameters

Ax	X coordinate of A
Ay	Y coordinate of A
Bx	X coordinate of B
By	Y coordinate of B
Px	X coordinate of P
Py	Y coordinate of P

Returns: -1 if reaching P takes a counter-clockwise (left) turn, 1 if reaching P takes a clockwise (right) turn, 0 if P is collinear with A-B

Since: 3.3

◆ GEOSOrientationIndex_r()

int GEOSOrientationIndex_r	(	GEOSContextHandle_t	handle,
		double	Ax,
		double	Ay,
		double	Bx,
		double	By,
		double	Px,
		double	Py
	)

See also: GEOSOrientationIndex

◆ GEOSOrientPolygons()

int GEOSOrientPolygons	(	GEOSGeometry *	g,
		int	exteriorCW
	)

Enforce a ring orientation on all polygonal elements in the input geometry. Non-polygonal geometries will not be modified.

Parameters

g	Input geometry
exteriorCW	if 1, exterior rings will be clockwise and interior rings will be counter-clockwise

Returns: 0 on success or -1 on exception

Since: 3.12

◆ GEOSOrientPolygons_r()

int GEOSOrientPolygons_r	(	GEOSContextHandle_t	handle,
		GEOSGeometry *	g,
		int	exteriorCW
	)

See also: GEOSOrientPolygons

◆ GEOSOverlaps()

char GEOSOverlaps	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

Tests if two geometries share interiors but are neither within nor contained.

Parameters

g1	Input geometry
g2	Input geometry

Returns: 1 on true, 0 on false, 2 on exception

See also: geos::geom::Geometry::overlaps

Since: 2.2

◆ GEOSOverlaps_r()

char GEOSOverlaps_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

See also: GEOSOverlaps

◆ GEOSPointOnSurface()

GEOSGeometry* GEOSPointOnSurface ( const GEOSGeometry * g )

Returns a point that is inside the boundary of a polygonal geometry.

Parameters

g	The input geometry

Returns: A point that is inside the input Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::algorithm::InteriorPointArea

Since: 2.2

◆ GEOSPointOnSurface_r()

GEOSGeometry* GEOSPointOnSurface_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSPointOnSurface

◆ GEOSPolygonHullSimplify()

GEOSGeometry* GEOSPolygonHullSimplify	(	const GEOSGeometry *	g,
		unsigned int	isOuter,
		double	vertexNumFraction
	)

Computes a boundary-respecting hull of a polygonal geometry, with hull shape determined by a target parameter specifying the fraction of the input vertices retained in the result. Larger values produce less concave results. A value of 1 produces the convex hull; a value of 0 produces the original geometry. An outer hull is computed if the parameter is positive, an inner hull is computed if it is negative.

Parameters

g	the polygonal geometry to process
isOuter	indicates whether to compute an outer or inner hull (1 for outer hull, 0 for inner)
vertexNumFraction	the target fraction of the count of input vertices to retain in result

Returns: A newly allocated geometry of the concave hull. NULL on exception.

Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::simplify::PolygonHullSimplifier

Since: 3.11

◆ GEOSPolygonHullSimplify_r()

GEOSGeometry* GEOSPolygonHullSimplify_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		unsigned int	isOuter,
		double	vertexNumFraction
	)

See also: GEOSPolygonHullSimplify

◆ GEOSPolygonHullSimplifyMode()

GEOSGeometry* GEOSPolygonHullSimplifyMode	(	const GEOSGeometry *	g,
		unsigned int	isOuter,
		unsigned int	parameterMode,
		double	parameter
	)

Computes a topology-preserving simplified hull of a polygonal geometry, with hull shape determined by the parameter, controlled by a parameter mode, which is one defined in GEOSPolygonHullParameterModes. Larger values compute less concave results and a value of 0 produces the original geometry. Either outer or inner hulls can be computed.

Parameters

g	the polygonal geometry to process
isOuter	indicates whether to compute an outer or inner hull (1 for outer hull, 0 for inner)
parameterMode	the interpretation to apply to the parameter argument; see GEOSPolygonHullParameterModes
parameter	the target ratio of area difference to original area

Returns: A newly allocated geometry of the concave hull. NULL on exception.

Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::simplify::PolygonHullSimplifier; GEOSPolygonHullParameterModes; GEOSPolygonHullSimplify

Since: 3.11

◆ GEOSPolygonHullSimplifyMode_r()

GEOSGeometry* GEOSPolygonHullSimplifyMode_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		unsigned int	isOuter,
		unsigned int	parameterMode,
		double	parameter
	)

See also: GEOSPolygonHullSimplifyMode

◆ GEOSPolygonize()

GEOSGeometry* GEOSPolygonize	(	const GEOSGeometry *const	geoms[],
		unsigned int	ngeoms
	)

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

All types of Geometry are accepted as input; the constituent linework is extracted as the edges to be polygonized.

The edges must be correctly noded; that is, they must only meet at their endpoints and not overlap anywhere. If your edges are not already noded, run them through GEOSUnaryUnion() first. Polygonization will accept incorrectly noded input but will not form polygons from non-noded edges, and reports them as errors.

The Polygonizer reports the following 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 a polygon
Invalid Ring Lines - edges which form rings which are invalid (e.g. the component lines contain a self-intersection)

Errors are reported to output parameters "cuts", "dangles" and "invalid" (if not-null). Formed polygons are returned as a collection. NULL is returned on exception. All returned geometries must be destroyed by caller.

The GEOSPolygonize_valid() variant allows extracting only polygons which form a valid polygonal result. The set of extracted polygons is guaranteed to be edge-disjoint. This is useful when it is known that the input lines form a valid polygonal geometry (which may include holes or nested polygons).

Parameters

geoms	Array of linear geometries to polygons. Caller retains ownersihp of both array container and objects.
ngeoms	Size of the geoms array.

Returns: The polygonal output geometry. Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::operation::polygonize::Polygonizer

Since: 2.2

◆ GEOSPolygonize_full()

GEOSGeometry* GEOSPolygonize_full	(	const GEOSGeometry *	input,
		GEOSGeometry **	cuts,
		GEOSGeometry **	dangles,
		GEOSGeometry **	invalid
	)

Perform the polygonization as GEOSPolygonize() and return the polygonal result as well as all extra outputs.

Parameters

[in]	input	A single geometry with all the input lines to polygonize.
[out]	cuts	Pointer to hold "cut edges", connected on both ends but not part of output. Caller must free.
[out]	dangles	Pointer to hold "dangles", connected one end but not part of output. Caller must free.
[out]	invalid	Pointer to hold invalid outputs, polygons formed but not valid. Caller must free.

Returns: The polygonal valid output Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::operation::polygonize::Polygonizer

Since: 3.3

◆ GEOSPolygonize_full_r()

GEOSGeometry* GEOSPolygonize_full_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	input,
		GEOSGeometry **	cuts,
		GEOSGeometry **	dangles,
		GEOSGeometry **	invalidRings
	)

See also: GEOSPolygonize_full

◆ GEOSPolygonize_r()

GEOSGeometry* GEOSPolygonize_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *const	geoms[],
		unsigned int	ngeoms
	)

See also: GEOSPolygonize

◆ GEOSPolygonize_valid()

GEOSGeometry* GEOSPolygonize_valid	(	const GEOSGeometry *const	geoms[],
		unsigned int	ngeoms
	)

Has the same polygonizing behavior as GEOSPolygonize(), but returns a result which is a valid polygonal geometry. The result will not contain any edge-adjacent elements.

Parameters

geoms	Array of linear geometries to polygons. Caller retains ownersihp of both array container and objects.
ngeoms	Size of the geoms array.

Returns: The polygonal output geometry. Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::operation::polygonize::Polygonizer; GEOSBuildArea()

Since: 3.8

◆ GEOSPolygonize_valid_r()

GEOSGeometry* GEOSPolygonize_valid_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *const	geoms[],
		unsigned int	ngems
	)

See also: GEOSPolygonize_valid

◆ GEOSPolygonizer_getCutEdges()

GEOSGeometry* GEOSPolygonizer_getCutEdges	(	const GEOSGeometry *const	geoms[],
		unsigned int	ngeoms
	)

Perform the polygonization as GEOSPolygonize() but return only the "cut edges", the linear features that are connected at both ends, do not participate in the final polygon.

Parameters

geoms	Array of linear geometries to polygons. Caller retains ownersihp of both array container and objects.
ngeoms	Size of the geoms array.

Returns: The "cut edges" Caller is responsible for freeing with GEOSGeom_destroy().

See also: geos::operation::polygonize::Polygonizer

Since: 3.1

◆ GEOSPolygonizer_getCutEdges_r()

GEOSGeometry* GEOSPolygonizer_getCutEdges_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *const	geoms[],
		unsigned int	ngeoms
	)

See also: GEOSPolygonizer_getCutEdges

◆ GEOSPrepare()

const GEOSPreparedGeometry* GEOSPrepare ( const GEOSGeometry * g )

Create a Prepared Geometry. The caller retains ownership of the base geometry, and after processing is complete, must free both the prepared and the base geometry. (Ideally, destroy the prepared geometry first, as it has an internal reference to the base geometry.)

Parameters

g	The base geometry to wrap in a prepared geometry.

Returns: A prepared geometry. Caller is responsible for freeing with GEOSPreparedGeom_destroy()

Since: 3.1

◆ GEOSPrepare_r()

const GEOSPreparedGeometry* GEOSPrepare_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g
	)

See also: GEOSPrepare

◆ GEOSPreparedContains()

char GEOSPreparedContains	(	const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

Use a GEOSPreparedGeometry do a high performance calculation of whether the provided geometry is contained.

Parameters

pg1	The prepared geometry
g2	The geometry to test

Returns: 1 on true, 0 on false, 2 on exception

See also: GEOSContains

Since: 3.1

◆ GEOSPreparedContains_r()

char GEOSPreparedContains_r	(	GEOSContextHandle_t	handle,
		const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

See also: GEOSPreparedContains

◆ GEOSPreparedContainsProperly()

char GEOSPreparedContainsProperly	(	const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

Use a GEOSPreparedGeometry do a high performance calculation of whether the provided geometry is contained properly.

Parameters

pg1	The prepared geometry
g2	The geometry to test

Returns: 1 on true, 0 on false, 2 on exception

See also: GEOSContainsProperly

Since: 3.1

◆ GEOSPreparedContainsProperly_r()

char GEOSPreparedContainsProperly_r	(	GEOSContextHandle_t	handle,
		const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

See also: GEOSPreparedContainsProperly

◆ GEOSPreparedContainsXY()

char GEOSPreparedContainsXY	(	const GEOSPreparedGeometry *	pg1,
		double	x,
		double	y
	)

Use a GEOSPreparedGeometry do a high performance calculation of whether the provided point is contained.

Parameters

pg1	The prepared geometry
x	x coordinate of point to test
y	y coordinate of point to test

Returns: 1 on true, 0 on false, 2 on exception

See also: GEOSContains

Since: 3.12

◆ GEOSPreparedContainsXY_r()

char GEOSPreparedContainsXY_r	(	GEOSContextHandle_t	handle,
		const GEOSPreparedGeometry *	pg1,
		double	x,
		double	y
	)

See also: GEOSPreparedContainsXY

◆ GEOSPreparedCoveredBy()

char GEOSPreparedCoveredBy	(	const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

Using a GEOSPreparedGeometry do a high performance calculation of whether the provided geometry is covered by.

Parameters

pg1	The prepared geometry
g2	The geometry to test

Returns: 1 on true, 0 on false, 2 on exception

See also: GEOSCoveredBy

Since: 3.3

◆ GEOSPreparedCoveredBy_r()

char GEOSPreparedCoveredBy_r	(	GEOSContextHandle_t	handle,
		const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

See also: GEOSPreparedCoveredBy

◆ GEOSPreparedCovers()

char GEOSPreparedCovers	(	const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

Using a GEOSPreparedGeometry do a high performance calculation of whether the provided geometry covers.

Parameters

pg1	The prepared geometry
g2	The geometry to test

Returns: 1 on true, 0 on false, 2 on exception

See also: GEOSCovers

Since: 3.1

◆ GEOSPreparedCovers_r()

char GEOSPreparedCovers_r	(	GEOSContextHandle_t	handle,
		const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

See also: GEOSPreparedCovers

◆ GEOSPreparedCrosses()

char GEOSPreparedCrosses	(	const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

Using a GEOSPreparedGeometry do a high performance calculation of whether the provided geometry crosses.

Parameters

pg1	The prepared geometry
g2	The geometry to test

Returns: 1 on true, 0 on false, 2 on exception

See also: GEOSCrosses

Since: 3.3

◆ GEOSPreparedCrosses_r()

char GEOSPreparedCrosses_r	(	GEOSContextHandle_t	handle,
		const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

See also: GEOSPreparedCrosses

◆ GEOSPreparedDisjoint()

char GEOSPreparedDisjoint	(	const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

Use a GEOSPreparedGeometry do a high performance calculation of whether the provided geometry is disjoint.

Parameters

pg1	The prepared geometry
g2	The geometry to test

Returns: 1 on true, 0 on false, 2 on exception

See also: GEOSDisjoint

Since: 3.3

◆ GEOSPreparedDisjoint_r()

char GEOSPreparedDisjoint_r	(	GEOSContextHandle_t	handle,
		const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

See also: GEOSPreparedDisjoint

◆ GEOSPreparedDistance()

int GEOSPreparedDistance	(	const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2,
		double *	dist
	)

Use a GEOSPreparedGeometry do a high performance calculation to find the distance between the prepared and provided geometry. Useful for situations where one geometry is large and static and needs to be tested against a large number of other geometries.

Parameters

[in]	pg1	The prepared geometry
[in]	g2	The geometry to test
[out]	dist	Pointer to store the result in

Returns: 1 on success

Since: 3.9

◆ GEOSPreparedDistance_r()

int GEOSPreparedDistance_r	(	GEOSContextHandle_t	handle,
		const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2,
		double *	dist
	)

See also: GEOSPreparedDistance

◆ GEOSPreparedDistanceWithin()

char GEOSPreparedDistanceWithin	(	const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2,
		double	dist
	)

Use a GEOSPreparedGeometry do a high performance calculation to find whether the prepared and provided geometry are within the given max distance. Useful for situations where one geometry is large and static and needs to be tested against a large number of other geometries.

Parameters

pg1	The prepared geometry
g2	The geometry to test
dist	The max distance

Returns: 1 on success

Since: 3.10

◆ GEOSPreparedDistanceWithin_r()

char GEOSPreparedDistanceWithin_r	(	GEOSContextHandle_t	handle,
		const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2,
		double	dist
	)

See also: GEOSPreparedDistanceWithin

◆ GEOSPreparedGeom_destroy()

void GEOSPreparedGeom_destroy ( const GEOSPreparedGeometry * g )

Free the memory associated with a GEOSPreparedGeometry. Caller must separately free the base GEOSGeometry used to create the prepared geometry.

Parameters

g	Prepared geometry to destroy.

Since: 3.1

◆ GEOSPreparedGeom_destroy_r()

void GEOSPreparedGeom_destroy_r	(	GEOSContextHandle_t	handle,
		const GEOSPreparedGeometry *	g
	)

See also: GEOSPreparedGeom_destroy

◆ GEOSPreparedIntersects()

char GEOSPreparedIntersects	(	const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

Use a GEOSPreparedGeometry do a high performance calculation of whether the provided geometry intersects.

Parameters

pg1	The prepared geometry
g2	The geometry to test

Returns: 1 on true, 0 on false, 2 on exception

See also: GEOSIntersects

Since: 3.1

◆ GEOSPreparedIntersects_r()

char GEOSPreparedIntersects_r	(	GEOSContextHandle_t	handle,
		const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

See also: GEOSPreparedIntersects

◆ GEOSPreparedIntersectsXY()

char GEOSPreparedIntersectsXY	(	const GEOSPreparedGeometry *	pg1,
		double	x,
		double	y
	)

Use a GEOSPreparedGeometry do a high performance calculation of whether the provided point intersects.

Parameters

pg1	The prepared geometry
x	x coordinate of point to test
y	y coordinate of point to test

Returns: 1 on true, 0 on false, 2 on exception

See also: GEOSIntersects

Since: 3.12

◆ GEOSPreparedIntersectsXY_r()

char GEOSPreparedIntersectsXY_r	(	GEOSContextHandle_t	handle,
		const GEOSPreparedGeometry *	pg1,
		double	x,
		double	y
	)

See also: GEOSPreparedIntersectsXY

◆ GEOSPreparedNearestPoints()

GEOSCoordSequence* GEOSPreparedNearestPoints	(	const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

Use a GEOSPreparedGeometry do a high performance calculation to find the nearest points between the prepared and provided geometry.

Parameters

pg1	The prepared geometry
g2	The geometry to test

Returns: A coordinate sequence containing the nearest points, or NULL on exception. The first point in the sequence is from the prepared geometry, and the seconds is from the other argument.

Since: 3.9

◆ GEOSPreparedNearestPoints_r()

GEOSCoordSequence* GEOSPreparedNearestPoints_r	(	GEOSContextHandle_t	handle,
		const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

See also: GEOSPreparedNearestPoints

◆ GEOSPreparedOverlaps()

char GEOSPreparedOverlaps	(	const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

Use a GEOSPreparedGeometry do a high performance calculation of whether the provided geometry overlaps.

Parameters

pg1	The prepared geometry
g2	The geometry to test

Returns: 1 on true, 0 on false, 2 on exception

See also: GEOSOverlaps

Since: 3.3

◆ GEOSPreparedOverlaps_r()

char GEOSPreparedOverlaps_r	(	GEOSContextHandle_t	handle,
		const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

See also: GEOSPreparedOverlaps

◆ GEOSPreparedRelate()

char* GEOSPreparedRelate	(	const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

Use a GEOSPreparedGeometry do a high-performance calculation of the DE9IM relationship between the prepared and provided geometry.

Parameters

pg1	The prepared geometry
g2	The geometry to test

Returns: The DE9IM string

See also: GEOSPrepare; GEOSRelate; GEOSPreparedRelatePattern

Since: 3.13

◆ GEOSPreparedRelate_r()

char* GEOSPreparedRelate_r	(	GEOSContextHandle_t	handle,
		const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

See also: GEOSPreparedRelate

◆ GEOSPreparedRelatePattern()

char GEOSPreparedRelatePattern	(	const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2,
		const char *	imPattern
	)

Use a GEOSPreparedGeometry do a high-performance calculation of the DE9IM relationship between the prepared and provided geometry, and compare the relationship to the provided DE9IM pattern. Returns true if the patterns are consistent and false otherwise.

Parameters

pg1	The prepared geometry
g2	The geometry to test
imPattern	The DE9IM pattern to test

Returns: 1 on true, 0 on false, 2 on exception

See also: GEOSPrepare; GEOSRelatePattern; GEOSPreparedRelate

Since: 3.13

◆ GEOSPreparedRelatePattern_r()

char GEOSPreparedRelatePattern_r	(	GEOSContextHandle_t	handle,
		const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2,
		const char *	im
	)

See also: GEOSPreparedRelatePattern

◆ GEOSPreparedTouches()

char GEOSPreparedTouches	(	const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

Use a GEOSPreparedGeometry do a high performance calculation of whether the provided geometry touches.

Parameters

pg1	The prepared geometry
g2	The geometry to test

Returns: 1 on true, 0 on false, 2 on exception

See also: GEOSTouches

Since: 3.3

◆ GEOSPreparedTouches_r()

char GEOSPreparedTouches_r	(	GEOSContextHandle_t	handle,
		const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

See also: GEOSPreparedTouches

◆ GEOSPreparedWithin()

char GEOSPreparedWithin	(	const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

Use a GEOSPreparedGeometry do a high performance calculation of whether the provided geometry is within.

Parameters

pg1	The prepared geometry
g2	The geometry to test

Returns: 1 on true, 0 on false, 2 on exception

See also: GEOSWithin

Since: 3.3

◆ GEOSPreparedWithin_r()

char GEOSPreparedWithin_r	(	GEOSContextHandle_t	handle,
		const GEOSPreparedGeometry *	pg1,
		const GEOSGeometry *	g2
	)

See also: GEOSPreparedWithin

◆ GEOSProject()

double GEOSProject	(	const GEOSGeometry *	line,
		const GEOSGeometry *	point
	)

Distance of point projected onto line from the start of the line.

Parameters

line	linear target of projection
point	point to be projected onto 'g'

Returns: distance along line that point projects to, -1 on exception

Note: Line parameter must be a LineString.

Since: 3.2

◆ GEOSProject_r()

double GEOSProject_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	line,
		const GEOSGeometry *	point
	)

See also: GEOSProject

◆ GEOSProjectNormalized()

double GEOSProjectNormalized	(	const GEOSGeometry *	line,
		const GEOSGeometry *	point
	)

Project point to line and calculate the proportion of the line the point is from the start. For example, a point that projects to the middle of a line would be return 0.5.

Parameters

line	linear target of projection
point	the point to project

Returns: The proportion of the overall line length that the projected point falls at.

Since: 3.2

◆ GEOSProjectNormalized_r()

double GEOSProjectNormalized_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g,
		const GEOSGeometry *	p
	)

See also: GEOSProjectNormalized

◆ GEOSRelate()

char* GEOSRelate	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

Calculate the DE9IM string for this geometry pair. The result is a 9-character string containing dimension symbols in the set "012F".

See also: geos::geom::Geometry::relate

Parameters

g1	First geometry in pair
g2	Second geometry in pair

Returns: DE9IM string. Caller is responsible for freeing with GEOSFree(). NULL on exception

Since: 2.2

◆ GEOSRelate_r()

char* GEOSRelate_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2
	)

See also: GEOSRelate

◆ GEOSRelateBoundaryNodeRule()

char* GEOSRelateBoundaryNodeRule	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		int	bnr
	)

Calculate the DE9IM string for this geometry pair, using the supplied GEOSRelateBoundaryNodeRules.

See also: geos::geom::Geometry::relate; geos::algorithm::BoundaryNodeRule

Parameters

g1	First geometry in pair
g2	Second geometry in pair
bnr	A member of the GEOSRelateBoundaryNodeRules enum

Returns: DE9IM string. Caller is responsible for freeing with GEOSFree(). NULL on exception

Since: 3.3

◆ GEOSRelateBoundaryNodeRule_r()

char* GEOSRelateBoundaryNodeRule_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		int	bnr
	)

See also: GEOSRelateBoundaryNodeRule

◆ GEOSRelatePattern()

char GEOSRelatePattern	(	const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		const char *	imPattern
	)

Calculate the DE9IM string for a geometry pair and compare against a DE9IM pattern. Returns true if the computed matrix matches the pattern. The pattern is a 9-character string containing symbols in the set "012TF*". "012F" match the corresponding dimension symbol; "T" matches any non-empty dimension; "*" matches any dimension.

See also: geos::geom::Geometry::relate

Parameters

g1	First geometry in pair
g2	Second geometry in pair
imPattern	DE9IM pattern to match

Returns: 1 on true, 0 on false, 2 on exception

Since: 2.2

◆ GEOSRelatePattern_r()

char GEOSRelatePattern_r	(	GEOSContextHandle_t	handle,
		const GEOSGeometry *	g1,
		const GEOSGeometry *	g2,
		const char *	imPattern
	)

See also: GEOSRelatePattern

◆ GEOSRelatePatternMatch()

char GEOSRelatePatternMatch	(	const char *	intMatrix,
		const char *	imPattern
	)

Compare a DE9IM string to a pattern and return true if they are consistent.

Parameters

intMatrix	DE9IM string (contains symbols "012F")
imPattern	Pattern to match to (may also contain symbols "T" and "*")

Returns: 1 on true, 0 on false, 2 on exception

Since: 3.3

◆ GEOSRelatePatternMatch_r()

char GEOSRelatePatternMatch_r	(	GEOSContextHandle_t	handle,
		const char *	intMatrix,
		const char *	imPattern
	)

See also: GEOSRelatePatternMatch

◆ GEOSRemoveRepeatedPoints()

GEOSGeometry* GEOSRemoveRepeatedPoints	(	const GEOSGeometry *	g,
		double	tolerance
	)

Works from start of each coordinate sequence in the geometry, retaining points that are further away from the previous retained point than the tolerance value.

Removing repeated points with a non-zero tolerance may result in an invalid geometry being returned. Be sure to check and repair validity.

Returns: A geometry with all points within the tolerance of each other removed.

Parameters

g	The geometry to filter
tolerance	Remove all points within this distance of each other. Use 0.0 to remove only exactly repeated points.

See also

Typedefs

Enumerations

Functions

Geometric Constructions

Detailed Description

Typedef Documentation

◆ GEOSBufferParams

◆ GEOSContextHandle_t

◆ GEOSCoordSequence

◆ GEOSDistanceCallback

◆ GEOSGeoJSONReader

◆ GEOSGeoJSONWriter

◆ GEOSGeometry

◆ GEOSInterruptCallback

◆ GEOSMakeValidParams

◆ GEOSMessageHandler

◆ GEOSMessageHandler_r

◆ GEOSPreparedGeometry

◆ GEOSQueryCallback

◆ GEOSSTRtree

◆ GEOSTransformXYCallback

◆ GEOSTransformXYZCallback

◆ GEOSWKBReader

◆ GEOSWKBWriter

◆ GEOSWKTReader

◆ GEOSWKTWriter

Enumeration Type Documentation

◆ GEOSBufCapStyles

◆ GEOSBufJoinStyles

◆ GEOSGeomTypes

◆ GEOSMakeValidMethods

◆ GEOSPolygonHullParameterModes

◆ GEOSPrecisionRules

◆ GEOSRelateBoundaryNodeRules

◆ GEOSValidFlags

◆ GEOSVoronoiFlags

◆ GEOSWKBByteOrders

◆ GEOSWKBFlavors

Function Documentation

◆ finishGEOS()

◆ finishGEOS_r()

◆ GEOS_finish_r()

◆ GEOS_getWKBByteOrder()

◆ GEOS_getWKBByteOrder_r()

◆ GEOS_getWKBOutputDims()

◆ GEOS_getWKBOutputDims_r()

◆ GEOS_init_r()

◆ GEOS_interruptCancel()

◆ GEOS_interruptRegisterCallback()

◆ GEOS_interruptRequest()

◆ GEOS_printDouble()

◆ GEOS_setWKBByteOrder()

◆ GEOS_setWKBByteOrder_r()

◆ GEOS_setWKBOutputDims()

◆ GEOS_setWKBOutputDims_r()

◆ GEOSArea()

◆ GEOSArea_r()

◆ GEOSBoundary()

◆ GEOSBoundary_r()

◆ GEOSBuffer()

◆ GEOSBuffer_r()

◆ GEOSBufferParams_create()

◆ GEOSBufferParams_create_r()

◆ GEOSBufferParams_destroy()

◆ GEOSBufferParams_destroy_r()

◆ GEOSBufferParams_setEndCapStyle()

◆ GEOSBufferParams_setEndCapStyle_r()

◆ GEOSBufferParams_setJoinStyle()

◆ GEOSBufferParams_setJoinStyle_r()

◆ GEOSBufferParams_setMitreLimit()

◆ GEOSBufferParams_setMitreLimit_r()

◆ GEOSBufferParams_setQuadrantSegments()

◆ GEOSBufferParams_setQuadrantSegments_r()

◆ GEOSBufferParams_setSingleSided()

◆ GEOSBufferParams_setSingleSided_r()

◆ GEOSBufferWithParams()

◆ GEOSBufferWithParams_r()

◆ GEOSBufferWithStyle()

◆ GEOSBufferWithStyle_r()

◆ GEOSBuildArea()