gg_advanced.h File Reference

Geometry handling functions: advanced. More...

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Macros
#define	GAIA2GEOS_ALL   0
	Gaia-to-GEOS: all geometries.
#define	GAIA2GEOS_ONLY_POINTS   1
	Gaia-to-GEOS: only geometries of the Point type.
#define	GAIA2GEOS_ONLY_LINESTRINGS   2
	Gaia-to-GEOS: only geometries of the Linestring type.
#define	GAIA2GEOS_ONLY_POLYGONS   3
	Gaia-to-GEOS: only geometries of the Polygon type.

Functions
GAIAGEO_DECLARE void	gaiaResetGeosMsg (void)
	Resets the GEOS error and warning messages to an empty state. More...
GAIAGEO_DECLARE void	gaiaResetGeosMsg_r (const void *p_cache)
	Resets the GEOS error and warning messages to an empty state. More...
GAIAGEO_DECLARE const char *	gaiaGetGeosErrorMsg (void)
	Return the latest GEOS error message (if any) More...
GAIAGEO_DECLARE const char *	gaiaGetGeosErrorMsg_r (const void *p_cache)
	Return the latest GEOS error message (if any) More...
GAIAGEO_DECLARE const char *	gaiaGetGeosWarningMsg (void)
	Return the latest GEOS warning message (if any) More...
GAIAGEO_DECLARE const char *	gaiaGetGeosWarningMsg_r (const void *p_cache)
	Return the latest GEOS warning message (if any) More...
GAIAGEO_DECLARE const char *	gaiaGetGeosAuxErrorMsg (void)
	Return the latest GEOS (auxiliary) error message (if any) More...
GAIAGEO_DECLARE const char *	gaiaGetGeosAuxErrorMsg_r (const void *p_cache)
	Return the latest GEOS (auxiliary) error message (if any) More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaCriticalPointFromGEOSmsg (void)
	Attempts to (possibile) return a Point Geometry extracted from the latest GEOS error / warning message. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaCriticalPointFromGEOSmsg_r (const void *p_cache)
	Attempts to (possibile) return a Point Geometry extracted from the latest GEOS error / warning message. More...
GAIAGEO_DECLARE void	gaiaSetGeosErrorMsg (const char *msg)
	Set the current GEOS error message. More...
GAIAGEO_DECLARE void	gaiaSetGeosErrorMsg_r (const void *p_cache, const char *msg)
	Set the current GEOS error message. More...
GAIAGEO_DECLARE void	gaiaSetGeosWarningMsg (const char *msg)
	Set the current GEOS warning message. More...
GAIAGEO_DECLARE void	gaiaSetGeosWarningMsg_r (const void *p_cache, const char *msg)
	Set the current GEOS warning message. More...
GAIAGEO_DECLARE void	gaiaSetGeosAuxErrorMsg (const char *msg)
	Set the current GEOS (auxiliary) error message. More...
GAIAGEO_DECLARE void	gaiaSetGeosAuxErrorMsg_r (const void *p_cache, const char *msg)
	Set the current GEOS (auxiliary) error message. More...
GAIAGEO_DECLARE void *	gaiaToGeos (const gaiaGeomCollPtr gaia)
	Converts a Geometry object into a GEOS Geometry. More...
GAIAGEO_DECLARE void *	gaiaToGeos_r (const void *p_cache, const gaiaGeomCollPtr gaia)
	Converts a Geometry object into a GEOS Geometry. More...
GAIAGEO_DECLARE void *	gaiaToGeosSelective (const gaiaGeomCollPtr gaia, int mode)
	Converts a Geometry object into a GEOS Geometry. More...
GAIAGEO_DECLARE void *	gaiaToGeosSelective_r (const void *p_cache, const gaiaGeomCollPtr gaia, int mode)
	Converts a Geometry object into a GEOS Geometry. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaFromGeos_XY (const void *geos)
	Converts a GEOS Geometry into a Geometry object [XY dims]. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaFromGeos_XY_r (const void *p_cache, const void *geos)
	Converts a GEOS Geometry into a Geometry object [XY dims]. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaFromGeos_XYZ (const void *geos)
	Converts a GEOS Geometry into a Geometry object [XYZ dims]. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaFromGeos_XYZ_r (const void *p_cache, const void *geos)
	Converts a GEOS Geometry into a Geometry object [XYZ dims]. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaFromGeos_XYM (const void *geos)
	Converts a GEOS Geometry into a Geometry object [XYM dims]. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaFromGeos_XYM_r (const void *p_cache, const void *geos)
	Converts a GEOS Geometry into a Geometry object [XYM dims]. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaFromGeos_XYZM (const void *geos)
	Converts a GEOS Geometry into a Geometry object [XYZM dims]. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaFromGeos_XYZM_r (const void *p_cache, const void *geos)
	Converts a GEOS Geometry into a Geometry object [XYZM dims]. More...
GAIAGEO_DECLARE int	gaiaIsSimple (gaiaGeomCollPtr geom)
	Checks if a Geometry object represents an OGC Simple Geometry. More...
GAIAGEO_DECLARE int	gaiaIsSimple_r (const void *p_cache, gaiaGeomCollPtr geom)
	Checks if a Geometry object represents an OGC Simple Geometry. More...
GAIAGEO_DECLARE int	gaiaIsClosed (gaiaLinestringPtr line)
	Checks if a Linestring object represents an OGC Closed Geometry. More...
GAIAGEO_DECLARE int	gaiaIsClosedGeom (gaiaGeomCollPtr geom)
	Checks if a Geometry object represents an OGC Closed Linestring. More...
GAIAGEO_DECLARE int	gaiaIsClosedGeom_r (const void *p_cache, gaiaGeomCollPtr geom)
	Checks if a Geometry object represents an OGC Closed Linestring. More...
GAIAGEO_DECLARE int	gaiaIsRing (gaiaLinestringPtr line)
	Checks if a Linestring object represents an OGC Ring Geometry. More...
GAIAGEO_DECLARE int	gaiaIsRing_r (const void *p_cache, gaiaLinestringPtr line)
	Checks if a Linestring object represents an OGC Ring Geometry. More...
GAIAGEO_DECLARE int	gaiaIsValid (gaiaGeomCollPtr geom)
	Checks if a Geometry object represents an OGC Valid Geometry. More...
GAIAGEO_DECLARE char *	gaiaIsValidReason (gaiaGeomCollPtr geom)
	return a TEXT string stating if a Geometry is valid and if not valid, a reason why More...
GAIAGEO_DECLARE char *	gaiaIsValidReason_r (const void *p_cache, gaiaGeomCollPtr geom)
	return a TEXT string stating if a Geometry is valid and if not valid, a reason why More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaIsValidDetail (gaiaGeomCollPtr geom)
	return a Geometry detail causing a Geometry to be invalid More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaIsValidDetail_r (const void *p_cache, gaiaGeomCollPtr geom)
	return a Geometry detail causing a Geometry to be invalid More...
GAIAGEO_DECLARE int	gaiaIsValid_r (const void *p_cache, gaiaGeomCollPtr geom)
	Checks if a Geometry object represents an OGC Valid Geometry. More...
GAIAGEO_DECLARE int	gaiaGeomCollLength (gaiaGeomCollPtr geom, double *length)
	Measures the total Length for a Geometry object. More...
GAIAGEO_DECLARE int	gaiaGeomCollLength_r (const void *p_cache, gaiaGeomCollPtr geom, double *length)
	Measures the total Length for a Geometry object. More...
GAIAGEO_DECLARE int	gaiaGeomCollLengthOrPerimeter (gaiaGeomCollPtr geom, int perimeter, double *length)
	Measures the total Length or Perimeter for a Geometry object. More...
GAIAGEO_DECLARE int	gaiaGeomCollLengthOrPerimeter_r (const void *p_cache, gaiaGeomCollPtr geom, int perimeter, double *length)
	Measures the total Length or Perimeter for a Geometry object. More...
GAIAGEO_DECLARE int	gaiaGeomCollArea (gaiaGeomCollPtr geom, double *area)
	Measures the total Area for a Geometry object. More...
GAIAGEO_DECLARE int	gaiaGeomCollArea_r (const void *p_cache, gaiaGeomCollPtr geom, double *area)
	Measures the total Area for a Geometry object. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaPolygonize (gaiaGeomCollPtr geom, int force_multi)
	Attempts to rearrange a generic Geometry object into a Polygon or MultiPolygon. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaPolygonize_r (const void *p_cache, gaiaGeomCollPtr geom, int force_multi)
	Attempts to rearrange a generic Geometry object into a Polygon or MultiPolygon. More...
GAIAGEO_DECLARE int	gaiaGeomCollEquals (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial relationship evalution: Equals. More...
GAIAGEO_DECLARE int	gaiaGeomCollEquals_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial relationship evalution: Equals. More...
GAIAGEO_DECLARE int	gaiaGeomCollDisjoint (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial relationship evalution: Disjoint. More...
GAIAGEO_DECLARE int	gaiaGeomCollDisjoint_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial relationship evalution: Disjoint. More...
GAIAGEO_DECLARE int	gaiaGeomCollPreparedDisjoint (const void *p_cache, gaiaGeomCollPtr geom1, unsigned char *blob1, int size1, gaiaGeomCollPtr geom2, unsigned char *blob2, int size2)
	Spatial relationship evalution: Disjoint (GEOSPreparedGeometry) More...
GAIAGEO_DECLARE int	gaiaGeomCollIntersects (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial relationship evalution: Intesects. More...
GAIAGEO_DECLARE int	gaiaGeomCollIntersects_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial relationship evalution: Intersects. More...
GAIAGEO_DECLARE int	gaiaGeomCollPreparedIntersects (const void *p_cache, gaiaGeomCollPtr geom1, unsigned char *blob1, int size1, gaiaGeomCollPtr geom2, unsigned char *blob2, int size2)
	Spatial relationship evalution: Intersects (GEOSPreparedGeometry) More...
GAIAGEO_DECLARE int	gaiaGeomCollOverlaps (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial relationship evalution: Overlaps. More...
GAIAGEO_DECLARE int	gaiaGeomCollOverlaps_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial relationship evalution: Overlaps. More...
GAIAGEO_DECLARE int	gaiaGeomCollPreparedOverlaps (const void *p_cache, gaiaGeomCollPtr geom1, unsigned char *blob1, int size1, gaiaGeomCollPtr geom2, unsigned char *blob2, int size2)
	Spatial relationship evalution: Overlaps (GEOSPreparedGeometry) More...
GAIAGEO_DECLARE int	gaiaGeomCollCrosses (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial relationship evalution: Crosses. More...
GAIAGEO_DECLARE int	gaiaGeomCollCrosses_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial relationship evalution: Crosses. More...
GAIAGEO_DECLARE int	gaiaGeomCollPreparedCrosses (const void *p_cache, gaiaGeomCollPtr geom1, unsigned char *blob1, int size1, gaiaGeomCollPtr geom2, unsigned char *blob2, int size2)
	Spatial relationship evalution: Crosses (GEOSPreparedGeometry) More...
GAIAGEO_DECLARE int	gaiaGeomCollContains (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial relationship evalution: Contains. More...
GAIAGEO_DECLARE int	gaiaGeomCollContains_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial relationship evalution: Contains. More...
GAIAGEO_DECLARE int	gaiaGeomCollPreparedContains (const void *p_cache, gaiaGeomCollPtr geom1, unsigned char *blob1, int size1, gaiaGeomCollPtr geom2, unsigned char *blob2, int size2)
	Spatial relationship evalution: Contains (GEOSPreparedGeometry) More...
GAIAGEO_DECLARE int	gaiaGeomCollWithin (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial relationship evalution: Within. More...
GAIAGEO_DECLARE int	gaiaGeomCollWithin_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial relationship evalution: Within. More...
GAIAGEO_DECLARE int	gaiaGeomCollPreparedWithin (const void *p_cache, gaiaGeomCollPtr geom1, unsigned char *blob1, int size1, gaiaGeomCollPtr geom2, unsigned char *blob2, int size2)
	Spatial relationship evalution: Within (GEOSPreparedGeometry) More...
GAIAGEO_DECLARE int	gaiaGeomCollTouches (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial relationship evalution: Touches. More...
GAIAGEO_DECLARE int	gaiaGeomCollTouches_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial relationship evalution: Touches. More...
GAIAGEO_DECLARE int	gaiaGeomCollPreparedTouches (const void *p_cache, gaiaGeomCollPtr geom1, unsigned char *blob1, int size1, gaiaGeomCollPtr geom2, unsigned char *blob2, int size2)
	Spatial relationship evalution: Touches (GEOSPreparedGeometry) More...
GAIAGEO_DECLARE int	gaiaGeomCollRelate (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2, const char *pattern)
	Spatial relationship evalution: Relate. More...
GAIAGEO_DECLARE int	gaiaGeomCollRelate_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2, const char *pattern)
	Spatial relationship evalution: Relate. More...
GAIAGEO_DECLARE int	gaiaGeomCollDistance (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2, double *dist)
	Calculates the maximum distance intercurring between two Geometry objects. More...
GAIAGEO_DECLARE int	gaiaGeomCollDistance_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2, double *dist)
	Calculates the maximum distance intercurring between two Geometry objects. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaGeometryIntersection (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial operator: Intersection. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaGeometryIntersection_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial operator: Intersection. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaGeometryUnion (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial operator: Union. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaGeometryUnion_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial operator: Union. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaUnionCascaded (gaiaGeomCollPtr geom)
	Spatial operator: Union Cascaded. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaUnionCascaded_r (const void *p_cache, gaiaGeomCollPtr geom)
	Spatial operator: Union Cascaded. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaGeometryDifference (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial operator: Difference. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaGeometryDifference_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial operator: Difference. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaGeometrySymDifference (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial operator: SymDifference. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaGeometrySymDifference_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial operator: SymDifference. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaBoundary (gaiaGeomCollPtr geom)
	Spatial operator: Boundary. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaBoundary_r (const void *p_cache, gaiaGeomCollPtr geom)
	Spatial operator: Boundary. More...
GAIAGEO_DECLARE int	gaiaGeomCollCentroid (gaiaGeomCollPtr geom, double *x, double *y)
	Spatial operator: Centroid. More...
GAIAGEO_DECLARE int	gaiaGeomCollCentroid_r (const void *p_cache, gaiaGeomCollPtr geom, double *x, double *y)
	Spatial operator: Centroid. More...
GAIAGEO_DECLARE int	gaiaGetPointOnSurface (gaiaGeomCollPtr geom, double *x, double *y)
	Spatial operator: PointOnSurface. More...
GAIAGEO_DECLARE int	gaiaGetPointOnSurface_r (const void *p_cache, gaiaGeomCollPtr geom, double *x, double *y)
	Spatial operator: PointOnSurface. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaGeomCollSimplify (gaiaGeomCollPtr geom, double tolerance)
	Spatial operator: Simplify. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaGeomCollSimplify_r (const void *p_cache, gaiaGeomCollPtr geom, double tolerance)
	Spatial operator: Simplify. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaGeomCollSimplifyPreserveTopology (gaiaGeomCollPtr geom, double tolerance)
	Spatial operator: Simplify [preserving topology]. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaGeomCollSimplifyPreserveTopology_r (const void *p_cache, gaiaGeomCollPtr geom, double tolerance)
	Spatial operator: Simplify [preserving topology]. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaConvexHull (gaiaGeomCollPtr geom)
	Spatial operator: ConvexHull. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaConvexHull_r (const void *p_cache, gaiaGeomCollPtr geom)
	Spatial operator: ConvexHull. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaGeomCollBuffer (gaiaGeomCollPtr geom, double radius, int points)
	Spatial operator: Buffer. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaGeomCollBuffer_r (const void *p_cache, gaiaGeomCollPtr geom, double radius, int points)
	Spatial operator: Buffer. More...
GAIAGEO_DECLARE int	gaiaHausdorffDistance (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2, double *dist)
	Calculates the Hausdorff distance intercurring between two Geometry objects. More...
GAIAGEO_DECLARE int	gaiaHausdorffDistance_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2, double *dist)
	Calculates the Hausdorff distance intercurring between two Geometry objects. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaOffsetCurve (gaiaGeomCollPtr geom, double radius, int points, int left_right)
	Spatial operator: Offset Curve. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaOffsetCurve_r (const void *p_cache, gaiaGeomCollPtr geom, double radius, int points, int left_right)
	Spatial operator: Offset Curve. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaSingleSidedBuffer (gaiaGeomCollPtr geom, double radius, int points, int left_right)
	Spatial operator: Single Sided Buffer. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaSingleSidedBuffer_r (const void *p_cache, gaiaGeomCollPtr geom, double radius, int points, int left_right)
	Spatial operator: Single Sided Buffer. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaSharedPaths (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial operator: Shared Paths. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaSharedPaths_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial operator: Shared Paths. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaLineInterpolatePoint (gaiaGeomCollPtr ln_geom, double fraction)
	Spatial operator: Line Interpolate Point. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaLineInterpolatePoint_r (const void *p_cache, gaiaGeomCollPtr ln_geom, double fraction)
	Spatial operator: Line Interpolate Point. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaLineInterpolateEquidistantPoints (gaiaGeomCollPtr ln_geom, double distance)
	Spatial operator: Line Interpolate Equidistant Points. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaLineInterpolateEquidistantPoints_r (const void *p_cache, gaiaGeomCollPtr ln_geom, double distance)
	Spatial operator: Line Interpolate Equidistant Points. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaLineSubstring (gaiaGeomCollPtr ln_geom, double start_fraction, double end_fraction)
	Spatial operator: Line Substring. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaLineSubstring_r (const void *p_cache, gaiaGeomCollPtr ln_geom, double start_fraction, double end_fraction)
	Spatial operator: Line Substring. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaShortestLine (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial operator: Shortest Line. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaShortestLine_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial operator: Shortest Line. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaSnap (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2, double tolerance)
	Spatial operator: Snap. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaSnap_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2, double tolerance)
	Spatial operator: Snap. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaLineMerge (gaiaGeomCollPtr geom)
	Spatial operator: Line Merge. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaLineMerge_r (const void *p_cache, gaiaGeomCollPtr geom)
	Spatial operator: Line Merge. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaLinesCutAtNodes (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Spatial operator: Line Cut At Nodes. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaUnaryUnion (gaiaGeomCollPtr geom)
	Spatial operator: Unary Union. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaUnaryUnion_r (const void *p_cache, gaiaGeomCollPtr geom)
	Spatial operator: Unary Union. More...
GAIAGEO_DECLARE double	gaiaLineLocatePoint (gaiaGeomCollPtr ln_geom, gaiaGeomCollPtr pt_geom)
	Determines the location of the closest Point on Linestring to the given Point. More...
GAIAGEO_DECLARE double	gaiaLineLocatePoint_r (const void *p_cache, gaiaGeomCollPtr ln_geom, gaiaGeomCollPtr pt_geom)
	Determines the location of the closest Point on Linestring to the given Point. More...
GAIAGEO_DECLARE int	gaiaGeomCollCovers (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Topology check: test if a Geometry covers another one. More...
GAIAGEO_DECLARE int	gaiaGeomCollCovers_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Topology check: test if a Geometry covers another one. More...
GAIAGEO_DECLARE int	gaiaGeomCollPreparedCovers (const void *p_cache, gaiaGeomCollPtr geom1, unsigned char *blob1, int size1, gaiaGeomCollPtr geom2, unsigned char *blob2, int size2)
	Topology check: test if a Geometry covers another one (GEOSPreparedGeometry) More...
GAIAGEO_DECLARE int	gaiaGeomCollCoveredBy (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Topology check: test if a Geometry is covered by another one. More...
GAIAGEO_DECLARE int	gaiaGeomCollCoveredBy_r (const void *p_cache, gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2)
	Topology check: test if a Geometry is covered by another one. More...
GAIAGEO_DECLARE int	gaiaGeomCollPreparedCoveredBy (const void *p_cache, gaiaGeomCollPtr geom1, unsigned char *blob1, int size1, gaiaGeomCollPtr geom2, unsigned char *blob2, int size2)
	Topology check: test if a Geometry is covered by another one (GEOSPreparedGeometry) More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaSquareGrid (gaiaGeomCollPtr geom, double origin_x, double origin_y, double size, int only_edges)
	Utility function: SquareGrid. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaSquareGrid_r (const void *p_cache, gaiaGeomCollPtr geom, double origin_x, double origin_y, double size, int only_edges)
	Utility function: SquareGrid. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaTriangularGrid (gaiaGeomCollPtr geom, double origin_x, double origin_y, double size, int only_edges)
	Utility function: TriangularGrid. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaTriangularGrid_r (const void *p_cache, gaiaGeomCollPtr geom, double origin_x, double origin_y, double size, int only_edges)
	Utility function: TriangularGrid. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaHexagonalGrid (gaiaGeomCollPtr geom, double origin_x, double origin_y, double size, int only_edges)
	Utility function: HexagonalGrid. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaHexagonalGrid_r (const void *p_cache, gaiaGeomCollPtr geom, double origin_x, double origin_y, double size, int only_edges)
	Utility function: HexagonalGrid. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaDelaunayTriangulation (gaiaGeomCollPtr geom, double tolerance, int only_edges)
	Delaunay Triangulation. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaDelaunayTriangulation_r (const void *p_cache, gaiaGeomCollPtr geom, double tolerance, int only_edges)
	Delaunay Triangulation. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaVoronojDiagram (gaiaGeomCollPtr geom, double extra_frame_size, double tolerance, int only_edges)
	Voronoj Diagram. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaVoronojDiagram_r (const void *p_cache, gaiaGeomCollPtr geom, double extra_frame_size, double tolerance, int only_edges)
	Voronoj Diagram. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaConcaveHull (gaiaGeomCollPtr geom, double factor, double tolerance, int allow_holes)
	Concave Hull. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaConcaveHull_r (const void *p_cache, gaiaGeomCollPtr geom, double factor, double tolerance, int allow_holes)
	Concave Hull. More...
GAIAGEO_DECLARE void	gaiaResetLwGeomMsg (void)
	Resets the LWGEOM error and warning messages to an empty state. More...
GAIAGEO_DECLARE const char *	gaiaGetLwGeomErrorMsg (void)
	Return the latest LWGEOM error message (if any) More...
GAIAGEO_DECLARE const char *	gaiaGetLwGeomWarningMsg (void)
	Return the latest LWGEOM warning message (if any) More...
GAIAGEO_DECLARE void	gaiaSetLwGeomErrorMsg (const char *msg)
	Set the current LWGEOM error message. More...
GAIAGEO_DECLARE void	gaiaSetLwGeomWarningMsg (const char *msg)
	Set the current LWGEOM warning message. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaMakeValid (gaiaGeomCollPtr geom)
	Utility function: MakeValid. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaMakeValidDiscarded (gaiaGeomCollPtr geom)
	Utility function: MakeValidDiscarded. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaSegmentize (gaiaGeomCollPtr geom, double dist)
	Utility function: Segmentize. More...
GAIAGEO_DECLARE int	gaiaAzimuth (double xa, double ya, double xb, double yb, double *azimuth)
	Utility function: Azimuth. More...
GAIAGEO_DECLARE int	gaiaEllipsoidAzimuth (double xa, double ya, double xb, double yb, double a, double b, double *azimuth)
	Utility function: EllipsoidAzimuth. More...
GAIAGEO_DECLARE int	gaiaProjectedPoint (double x1, double y1, double a, double b, double distance, double azimuth, double *x2, double *y2)
	Utility function: ProjectedPoint. More...
GAIAGEO_DECLARE char *	gaiaGeoHash (gaiaGeomCollPtr geom, int precision)
	Utility function: GeoHash. More...
GAIAGEO_DECLARE char *	gaiaAsX3D (gaiaGeomCollPtr geom, const char *srs, int precision, int options, const char *refid)
	Utility function: AsX3D. More...
GAIAGEO_DECLARE int	gaia3DDistance (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2, double *dist)
	Calculates the minimum 3D distance intercurring between two Geometry objects. More...
GAIAGEO_DECLARE int	gaiaMaxDistance (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2, double *dist)
	Calculates the maximum 2D distance intercurring between two Geometry objects. More...
GAIAGEO_DECLARE int	gaia3DMaxDistance (gaiaGeomCollPtr geom1, gaiaGeomCollPtr geom2, double *dist)
	Calculates the maximum 3D distance intercurring between two Geometry objects. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaSplit (gaiaGeomCollPtr input, gaiaGeomCollPtr blade)
	Utility function: Split. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaSplitLeft (gaiaGeomCollPtr input, gaiaGeomCollPtr blade)
	Utility function: SplitLeft. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaSplitRight (gaiaGeomCollPtr input, gaiaGeomCollPtr blade)
	Utility function: SplitRight. More...
GAIAGEO_DECLARE int	gaiaGeodesicArea (gaiaGeomCollPtr geom, double a, double b, int use_ellipsoid, double *area)
	Measures the total Area for a Geometry object (geodesic) More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaNodeLines (gaiaGeomCollPtr input)
	Utility function: re-noding lines. More...
GAIAGEO_DECLARE gaiaGeomCollPtr	gaiaSnapToGrid (gaiaGeomCollPtr geom, double origin_x, double origin_y, double origin_z, double origin_m, double size_x, double size_y, double size_z, double size_m)
	Utility function: SnapToGrid. More...

Detailed Description

Geometry handling functions: advanced.

Function Documentation

GAIAGEO_DECLARE int gaia3DDistance	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2,
		double *	dist
	)

Calculates the minimum 3D distance intercurring between two Geometry objects.

Parameters

geom1	the first Geometry object
geom2	the second Geometry object
dist	on completion this variable will contain the calculated distance

Returns

0 on failure: any other value on success.

See also

gaiaGeomCollDistance, gaiaMaxDistance, gaia3DMaxDisance

Note

this function computes the 3D cartesian distance (if Z is supported)

Remarks

LWGEOM support required.

GAIAGEO_DECLARE int gaia3DMaxDistance	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2,
		double *	dist
	)

Calculates the maximum 3D distance intercurring between two Geometry objects.

Parameters

geom1	the first Geometry object
geom2	the second Geometry object
dist	on completion this variable will contain the calculated distance

Returns

0 on failure: any other value on success.

See also

gaiaGeomCollDistance, gaia3DDistance, gaiaMaxDistance

Note

this function computes the 3D maximum cartesian distance (if Z is supported)

Remarks

LWGEOM support required.

GAIAGEO_DECLARE char* gaiaAsX3D	(	gaiaGeomCollPtr	geom,
		const char *	srs,
		int	precision,
		int	options,
		const char *	refid
	)

Utility function: AsX3D.

Parameters

geom	the input geometry.
srs	the WKT SRS definition.
precision	the expected precision (coord decimal digits).
options
refid	the X3D namespace

Returns

NULL on failure: a null-terminated text string on success

Note

you are responsible to free (before or after) any text string returned by gaiaAsX3D()

Remarks

LWGEOM support required.

GAIAGEO_DECLARE int gaiaAzimuth	(	double	xa,
		double	ya,
		double	xb,
		double	yb,
		double *	azimuth
	)

Utility function: Azimuth.

Parameters

xa	the X coordinate of PointA.
ya	the Y coordinate of PointA.
xb	the X ccordinate of PointB.
yb	the Y coordinate of PointB.
azimuth	on completion this variable will contain the angle in radians from the horizontal of the vector defined by pointA and pointB. Angle is computed clockwise from down-to-up: on the clock: 12=0; 3=PI/2; 6=PI; 9=3PI/2.

Returns

0 on failure: any other value on success

See also

gaiaProjectedPoint

Remarks

LWGEOM support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaBoundary

(

gaiaGeomCollPtr

geom

)

Spatial operator: Boundary.

Parameters

geom	the Geometry object to be evaluated

Returns

the pointer to newly created Geometry object representing the geometry Boundary of the input Geometry: NULL on failure.

See also

gaiaBoudary_r, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaBoundary()
not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaBoundary_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom
	)

Spatial operator: Boundary.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	the Geometry object to be evaluated

Returns

the pointer to newly created Geometry object representing the geometry Boundary of the input Geometry: NULL on failure.

See also

gaiaBoudary, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaBoundary_r()
reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaConcaveHull	(	gaiaGeomCollPtr	geom,
		double	factor,
		double	tolerance,
		int	allow_holes
	)

Concave Hull.

Parameters

geom	pointer to input Geometry object.
factor	multiplier used for filtering Delaunay triangles: please read the note.
tolerance	optional snapping tolerance.
allow_holes	if FALSE any interior hole will be suppressed.

Returns

the pointer to newly created Geometry object (always of the Polygon type): NULL on failure.
NULL will be returned if any argument is invalid.

See also

gaiaConcaveHull_r, gaiaFreeGeomColl, gaiaDelaunayTriangulation

Note

This function will first create the Delauany Triangulation corresponding to input Geometry, determining at the same time the standard deviation for all edge's lengths.
Then in a second pass all Delaunay's triangles will be filtered, and all triangles presenting at least one edge longer than standard deviation * factor will be discarded.
All filtered triangles will then be merged altogether so to create the Concave Hull.

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaConcaveHull()
not reentrant and thread unsafe.

Remarks

GEOS-TRUNK support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaConcaveHull_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom,
		double	factor,
		double	tolerance,
		int	allow_holes
	)

Concave Hull.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	pointer to input Geometry object.
factor	multiplier used for filtering Delaunay triangles: please read the note.
tolerance	optional snapping tolerance.
allow_holes	if FALSE any interior hole will be suppressed.

Returns

the pointer to newly created Geometry object (always of the Polygon type): NULL on failure.
NULL will be returned if any argument is invalid.

See also

gaiaConcaveHull, gaiaFreeGeomColl, gaiaDelaunayTriangulation

Note

This function will first create the Delauany Triangulation corresponding to input Geometry, determining at the same time the standard deviation for all edge's lengths.
Then in a second pass all Delaunay's triangles will be filtered, and all triangles presenting at least one edge longer than standard deviation * factor will be discarded.
All filtered triangles will then be merged altogether so to create the Concave Hull.

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaConcaveHull_r()
reentrant and thread-safe.

Remarks

GEOS-TRUNK support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaConvexHull

(

gaiaGeomCollPtr

geom

)

Spatial operator: ConvexHull.

Parameters

geom	the input Geometry object

Returns

the pointer to newly created Geometry object representing the ConvexHull of input Geometry: NULL on failure.

See also

gaiaConvexHull_r, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaConvexHull()
not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaConvexHull_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom
	)

Spatial operator: ConvexHull.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	the input Geometry object

Returns

the pointer to newly created Geometry object representing the ConvexHull of input Geometry: NULL on failure.

See also

gaiaConvexHull, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaConvexHull_r()
reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaCriticalPointFromGEOSmsg

(

void

)

Attempts to (possibile) return a Point Geometry extracted from the latest GEOS error / warning message.

Returns

a Point Geometry: NULL if no warning/error was previoysly found or if the current GEOS message doesn't contains a critical Point.

See also

gaiaCriticalPointFromGEOSmsg_r, gaiaResetGeosMsg, gaiaGetGeosErrorMsg, gaiaGetGeosWarningMsg, gaiaSetGeosErrorMsg, gaiaSetGeosWarningMsg, gaiaSetGeosAuxErrorMsg

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaCriticalPointFromGEOSmsg_r

(

const void *

p_cache

)

Attempts to (possibile) return a Point Geometry extracted from the latest GEOS error / warning message.

Parameters

p_cache

a memory pointer returned by spatialite_alloc_connection()

Returns

a Point Geometry: NULL if no warning/error was previoysly found or if the current GEOS message doesn't contains a critical Point.

See also

gaiaCriticalPointFromGEOSmsg_r, gaiaResetGeosMsg, gaiaGetGeosErrorMsg, gaiaGetGeosWarningMsg, gaiaSetGeosErrorMsg, gaiaSetGeosWarningMsg, gaiaSetGeosAuxErrorMsg

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaDelaunayTriangulation	(	gaiaGeomCollPtr	geom,
		double	tolerance,
		int	only_edges
	)

Delaunay Triangulation.

Parameters

geom	pointer to input Geometry object.
tolerance	optional snapping tolerance.
only_edges	if non-zero will return a MULTILINESTRING, otherwise it will return a MULTIPOLYGON containing triangular POLYGONs.

Returns

the pointer to newly created Geometry object: NULL on failure.
NULL will be returned if any argument is invalid.

See also

gaiaDelaunatTriangulation_r, gaiaFreeGeomColl, gaiaVoronojDiagram, gaiaConcaveHull

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaDelaunayTriangulation()
not reentrant and thread unsafe.

Remarks

GEOS-TRUNK support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaDelaunayTriangulation_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom,
		double	tolerance,
		int	only_edges
	)

Delaunay Triangulation.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	pointer to input Geometry object.
tolerance	optional snapping tolerance.
only_edges	if non-zero will return a MULTILINESTRING, otherwise it will return a MULTIPOLYGON containing triangular POLYGONs.

Returns

the pointer to newly created Geometry object: NULL on failure.
NULL will be returned if any argument is invalid.

See also

gaiaDelaunatTriangulation, gaiaFreeGeomColl, gaiaVoronojDiagram, gaiaConcaveHull

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaDelaunayTriangulation_r()
reentrant and thread-safe.

Remarks

GEOS-TRUNK support required.

GAIAGEO_DECLARE int gaiaEllipsoidAzimuth	(	double	xa,
		double	ya,
		double	xb,
		double	yb,
		double	a,
		double	b,
		double *	azimuth
	)

Utility function: EllipsoidAzimuth.

Parameters

xa	the X coordinate of PointA.
ya	the Y coordinate of PointA.
xb	the X ccordinate of PointB.
yb	the Y coordinate of PointB.
a	major axis of the reference spheroid.
b	minor axis of the reference spheroid.
azimuth	on completion this variable will contain the angle in radians from the horizontal of the vector defined by pointA and pointB. Angle is computed clockwise from down-to-up: on the clock: 12=0; 3=PI/2; 6=PI; 9=3PI/2.

Returns

0 on failure: any other value on success

See also

gaiaAzimuth

Remarks

LWGEOM support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaFromGeos_XY

(

const void *

geos

)

Converts a GEOS Geometry into a Geometry object [XY dims].

Parameters

geos	handle to GEOS Geometry

Returns

the pointer to the newly created Geometry object

See also

gaiaFromGeos_XY_r, gaiaToGeos, gaiaFromGeos_XYZ, gaiaFromGeos_XYM, gaiaFromGeos_XYZM

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaFromGeos_XY()
not reentrant and thread usafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaFromGeos_XY_r	(	const void *	p_cache,
		const void *	geos
	)

Converts a GEOS Geometry into a Geometry object [XY dims].

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geos	handle to GEOS Geometry

Returns

the pointer to the newly created Geometry object

See also

gaiaFromGeos_XY, gaiaToGeos, gaiaFromGeos_XYZ, gaiaFromGeos_XYM, gaiaFromGeos_XYZM

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaFromGeos_XY_r()
reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaFromGeos_XYM

(

const void *

geos

)

Converts a GEOS Geometry into a Geometry object [XYM dims].

Parameters

geos	handle to GEOS Geometry

Returns

the pointer to the newly created Geometry object

See also

gaiaFromGeos_XYM_r, gaiaToGeos, gaiaFromGeos_XY, gaiaFromGeos_XYZ, gaiaFromGeos_XYZM

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaFromGeos_XYM()
not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaFromGeos_XYM_r	(	const void *	p_cache,
		const void *	geos
	)

Converts a GEOS Geometry into a Geometry object [XYM dims].

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geos	handle to GEOS Geometry

Returns

the pointer to the newly created Geometry object

See also

gaiaFromGeos_XYM, gaiaToGeos, gaiaFromGeos_XY, gaiaFromGeos_XYZ, gaiaFromGeos_XYZM

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaFromGeos_XYM_r()
reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaFromGeos_XYZ

(

const void *

geos

)

Converts a GEOS Geometry into a Geometry object [XYZ dims].

Parameters

geos	handle to GEOS Geometry

Returns

the pointer to the newly created Geometry object

See also

gaiaFromGeos_XYZ_r, gaiaToGeos, gaiaFromGeos_XY, gaiaFromGeos_XYM, gaiaFromGeos_XYZM

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaFromGeos_XYZ()
not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaFromGeos_XYZ_r	(	const void *	p_cache,
		const void *	geos
	)

Converts a GEOS Geometry into a Geometry object [XYZ dims].

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geos	handle to GEOS Geometry

Returns

the pointer to the newly created Geometry object

See also

gaiaFromGeos_XYZ, gaiaToGeos, gaiaFromGeos_XY, gaiaFromGeos_XYM, gaiaFromGeos_XYZM

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaFromGeos_XYZ_r()
reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaFromGeos_XYZM

(

const void *

geos

)

Converts a GEOS Geometry into a Geometry object [XYZM dims].

Parameters

geos	handle to GEOS Geometry

Returns

the pointer to the newly created Geometry object

See also

gaiaFromGeos_XYZM_r, gaiaToGeos, gaiaFromGeos_XY, gaiaFromGeos_XYZ, gaiaFromGeos_XYM

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaFromGeos_XYZM()
not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaFromGeos_XYZM_r	(	const void *	p_cache,
		const void *	geos
	)

Converts a GEOS Geometry into a Geometry object [XYZM dims].

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geos	handle to GEOS Geometry

Returns

the pointer to the newly created Geometry object

See also

gaiaFromGeos_XYZM, gaiaToGeos, gaiaFromGeos_XY, gaiaFromGeos_XYZ, gaiaFromGeos_XYM

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaFromGeos_XYZM_r()
reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeodesicArea	(	gaiaGeomCollPtr	geom,
		double	a,
		double	b,
		int	use_ellipsoid,
		double *	area
	)

Measures the total Area for a Geometry object (geodesic)

Parameters

geom	pointer to Geometry object
a	major axis of the reference spheroid.
b	minor axis of the reference spheroid.
use_ellipsoid	if TRUE will measure the Area on the Ellipsoid, otherwise on the Sphere
area	on completion this variable will contain the measured area

Returns

0 on failure: any other value on success

See also

gaiaGeomCollLength, gaiaMeasureArea, gaiaGeomCollArea

Remarks

LWGEOM support required.

GAIAGEO_DECLARE char* gaiaGeoHash	(	gaiaGeomCollPtr	geom,
		int	precision
	)

Utility function: GeoHash.

Parameters

geom	the input geometry.
precision	the expected precision: if <= 0 will be automatically determined.

Returns

NULL on failure: a null-terminated text string on success

Note

you are responsible to free (before or after) any text string returned by gaiaGeoHash()

Remarks

LWGEOM support required.

GAIAGEO_DECLARE int gaiaGeomCollArea	(	gaiaGeomCollPtr	geom,
		double *	area
	)

Measures the total Area for a Geometry object.

Parameters

geom	pointer to Geometry object
area	on completion this variable will contain the measured area

Returns

0 on failure: any other value on success

See also

gaiaGeoCollArea_r, gaiaGeomCollLength, gaiaMeasureArea, gaiaGeodesicArea

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

Examples:

demo1.c.

GAIAGEO_DECLARE int gaiaGeomCollArea_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom,
		double *	area
	)

Measures the total Area for a Geometry object.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	pointer to Geometry object
area	on completion this variable will contain the measured area

Returns

0 on failure: any other value on success

See also

gaiaGeoCollArea, gaiaGeomCollLength, gaiaMeasureArea, gaiaGeodesicArea

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaGeomCollBuffer	(	gaiaGeomCollPtr	geom,
		double	radius,
		int	points
	)

Spatial operator: Buffer.

Parameters

geom	the input Geometry object
radius	the buffer's radius
points	number of points (aka vertices) to be used in order to approximate a circular arc.

Returns

the pointer to newly created Geometry object representing the Buffer of input Geometry: NULL on failure.

See also

gaiaGeomCollBuffer_r, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaGeomCollBuffer()
not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaGeomCollBuffer_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom,
		double	radius,
		int	points
	)

Spatial operator: Buffer.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	the input Geometry object
radius	the buffer's radius
points	number of points (aka vertices) to be used in order to approximate a circular arc.

Returns

the pointer to newly created Geometry object representing the Buffer of input Geometry: NULL on failure.

See also

gaiaGeomCollBuffer, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaGeomCollBuffer_r()
reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollCentroid	(	gaiaGeomCollPtr	geom,
		double *	x,
		double *	y
	)

Spatial operator: Centroid.

Parameters

geom	pointer to Geometry object.
x	on completion this variable will contain the centroid X coordinate
y	on completion this variable will contain the centroid Y coordinate

Returns

0 on failure: any other value on success

See also

gaiaGeomCollCentroid_r, gaiaRingCentroid

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollCentroid_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom,
		double *	x,
		double *	y
	)

Spatial operator: Centroid.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	pointer to Geometry object.
x	on completion this variable will contain the centroid X coordinate
y	on completion this variable will contain the centroid Y coordinate

Returns

0 on failure: any other value on success

See also

gaiaGeomCollCentroid, gaiaRingCentroid

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollContains	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial relationship evalution: Contains.

Parameters

geom1	the first Geometry object to be evaluated
geom2	the second Geometry object to be evaluated

Returns

0 if false: any other value if true

See also

gaiaGeomCollContains_r, gaiaGeomCollPreparedContains, gaiaGeomCollEquals, gaiaGeomCollDisjoint, gaiaGeomCollIntersects, gaiaGeomCollOverlaps, gaiaGeomCollCrosses, gaiaGeomCollWithin, gaiaGeomCollTouches, gaiaGeomCollRelate

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollContains_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial relationship evalution: Contains.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object to be evaluated
geom2	the second Geometry object to be evaluated

Returns

0 if false: any other value if true

See also

gaiaGeomCollContains, gaiaGeomCollPreparedContains, gaiaGeomCollEquals, gaiaGeomCollDisjoint, gaiaGeomCollIntersects, gaiaGeomCollOverlaps, gaiaGeomCollCrosses, gaiaGeomCollWithin, gaiaGeomCollTouches, gaiaGeomCollRelate

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollCoveredBy	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Topology check: test if a Geometry is covered by another one.

Parameters

geom1	pointer to first input Geometry object.
geom2	pointer to second input Geometry object.

Returns

0 if false; any other value if geom2 is spatially covered by geom1.

See also

gaiaGeomCollCoveredBy_r, gaiaGeomCollPreparedCoveredBy, gaiaGeomCollCovers

Note

not reentrant and thread unsafe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE int gaiaGeomCollCoveredBy_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Topology check: test if a Geometry is covered by another one.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	pointer to first input Geometry object.
geom2	pointer to second input Geometry object.

Returns

0 if false; any other value if geom2 is spatially covered by geom1.

See also

gaiaGeomCollCoveredBy, gaiaGeomCollPreparedCoveredBy, gaiaGeomCollCovers

Note

reentrant and thread-safe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE int gaiaGeomCollCovers	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Topology check: test if a Geometry covers another one.

Parameters

geom1	pointer to first input Geometry object.
geom2	pointer to second input Geometry object.

Returns

0 if false; any other value if geom1 spatially covers geom2.

See also

gaiaGeomCollCovers_r, gaiaGeomCollPreparedCovers, gaiaGeomCollCoveredBy

Note

not reentrant and thead unsafe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE int gaiaGeomCollCovers_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Topology check: test if a Geometry covers another one.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	pointer to first input Geometry object.
geom2	pointer to second input Geometry object.

Returns

0 if false; any other value if geom1 spatially covers geom2.

See also

gaiaGeomCollCovers, gaiaGeomCollPreparedCovers, gaiaGeomCollCoveredBy

Note

reentrant and thead-safe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE int gaiaGeomCollCrosses	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial relationship evalution: Crosses.

Parameters

geom1	the first Geometry object to be evaluated
geom2	the second Geometry object to be evaluated

Returns

0 if false: any other value if true

See also

gaiaGeomCollCrosses_r, gaiaGeomCollPreparedCrosses, gaiaGeomCollEquals, gaiaGeomCollDisjoint, gaiaGeomCollIntersects, gaiaGeomCollOverlaps, gaiaGeomCollContains, gaiaGeomCollWithin, gaiaGeomCollTouches, gaiaGeomCollRelate

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollCrosses_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial relationship evalution: Crosses.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object to be evaluated
geom2	the second Geometry object to be evaluated

Returns

0 if false: any other value if true

See also

gaiaGeomCollCrosses, gaiaGeomCollPreparedCrosses, gaiaGeomCollEquals, gaiaGeomCollDisjoint, gaiaGeomCollIntersects, gaiaGeomCollOverlaps, gaiaGeomCollContains, gaiaGeomCollWithin, gaiaGeomCollTouches, gaiaGeomCollRelate

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollDisjoint	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial relationship evalution: Disjoint.

Parameters

geom1	the first Geometry object to be evaluated
geom2	the second Geometry object to be evaluated

Returns

0 if false: any other value if true

See also

gaiaGeomCollDisjoint_r, gaiaGeomCollEquals, gaiaGeomCollIntersects, gaiaGeomCollOverlaps, gaiaGeomCollCrosses, gaiaGeomCollContains, gaiaGeomCollWithin, gaiaGeomCollTouches, gaiaGeomCollRelate

Note

Obsolete: not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollDisjoint_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial relationship evalution: Disjoint.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object to be evaluated
geom2	the second Geometry object to be evaluated

Returns

0 if false: any other value if true

See also

gaiaGeomCollDisjoint_r, gaiaGeomCollEquals, gaiaGeomCollIntersects, gaiaGeomCollOverlaps, gaiaGeomCollCrosses, gaiaGeomCollContains, gaiaGeomCollWithin, gaiaGeomCollTouches, gaiaGeomCollRelate

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollDistance	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2,
		double *	dist
	)

Calculates the maximum distance intercurring between two Geometry objects.

Parameters

geom1	the first Geometry object
geom2	the second Geometry object
dist	on completion this variable will contain the calculated distance

Returns

0 on failure: any other value on success.

See also

gaiaGeomCollDistance_r, gaia3DDistance, gaiaMaxDistance, gaia3DMaxDistance

Note

this function always computes the 2D cartesian distance.
not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollDistance_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2,
		double *	dist
	)

Calculates the maximum distance intercurring between two Geometry objects.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object
geom2	the second Geometry object
dist	on completion this variable will contain the calculated distance

Returns

0 on failure: any other value on success.

See also

gaiaGeomCollDistance, gaia3DDistance, gaiaMaxDistance, gaia3DMaxDistance

Note

this function always computes the 2D cartesian distance.
reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollEquals	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial relationship evalution: Equals.

Parameters

geom1	the first Geometry object to be evaluated
geom2	the second Geometry object to be evaluated

Returns

0 if false: any other value if true

See also

gaiaGeomCollEquals_r, gaiaGeomCollDisjoint, gaiaGeomCollIntersects, gaiaGeomCollOverlaps, gaiaGeomCollCrosses, gaiaGeomCollContains, gaiaGeomCollWithin, gaiaGeomCollTouches, gaiaGeomCollRelate

Note

Obsolete: not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollEquals_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial relationship evalution: Equals.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object to be evaluated
geom2	the second Geometry object to be evaluated

Returns

0 if false: any other value if true

See also

gaiaGeomCollEquals, gaiaGeomCollDisjoint, gaiaGeomCollIntersects, gaiaGeomCollOverlaps, gaiaGeomCollCrosses, gaiaGeomCollContains, gaiaGeomCollWithin, gaiaGeomCollTouches, gaiaGeomCollRelate

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollIntersects	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial relationship evalution: Intesects.

Parameters

geom1	the first Geometry object to be evaluated
geom2	the second Geometry object to be evaluated

Returns

0 if false: any other value if true

See also

gaiaGeomCollIntersects_r, gaiaGeomCollPreparedIntersects, gaiaGeomCollEquals, gaiaGeomCollDisjoint, gaiaGeomCollOverlaps, gaiaGeomCollCrosses, gaiaGeomCollContains, gaiaGeomCollWithin, gaiaGeomCollTouches, gaiaGeomCollRelate

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollIntersects_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial relationship evalution: Intersects.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object to be evaluated
geom2	the second Geometry object to be evaluated

Returns

0 if false: any other value if true

See also

gaiaGeomCollIntersects, gaiaGeomCollPreparedIntersects, gaiaGeomCollEquals, gaiaGeomCollDisjoint, gaiaGeomCollOverlaps, gaiaGeomCollCrosses, gaiaGeomCollContains, gaiaGeomCollWithin, gaiaGeomCollTouches, gaiaGeomCollRelate

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollLength	(	gaiaGeomCollPtr	geom,
		double *	length
	)

Measures the total Length for a Geometry object.

Parameters

geom	pointer to Geometry object
length	on completion this variable will contain the measured length

Returns

0 on failure: any other value on success

See also

gaiaGeomCollLenght_r, gaiaGeomCollArea, gaiaMeasureLength, gaiaGeomCollLengthOrPerimeter

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

Examples:

demo1.c.

GAIAGEO_DECLARE int gaiaGeomCollLength_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom,
		double *	length
	)

Measures the total Length for a Geometry object.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	pointer to Geometry object
length	on completion this variable will contain the measured length

Returns

0 on failure: any other value on success

See also

gaiaGeomCollLenght, gaiaGeomCollArea, gaiaMeasureLength, gaiaGeomCollLengthOrPerimeter

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollLengthOrPerimeter	(	gaiaGeomCollPtr	geom,
		int	perimeter,
		double *	length
	)

Measures the total Length or Perimeter for a Geometry object.

Parameters

geom	pointer to Geometry object
perimeter	if TRUE only Polygons will be considered, ignoring any Linesting the opposite if FALSE (considering only Linestrings and ignoring any Polygon)
length	on completion this variable will contain the measured length or perimeter

Returns

0 on failure: any other value on success

See also

gaiaGeomCollLengthOrPerimeter_r, gaiaGeomCollArea, gaiaMeasureLength, gaiaGeomCollLength

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollLengthOrPerimeter_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom,
		int	perimeter,
		double *	length
	)

Measures the total Length or Perimeter for a Geometry object.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	pointer to Geometry object
perimeter	if TRUE only Polygons will be considered, ignoring any Linesting the opposite if FALSE (considering only Linestrings and ignoring any Polygon)
length	on completion this variable will contain the measured length or perimeter

Returns

0 on failure: any other value on success

See also

gaiaGeomCollLengthOrPerimeter, gaiaGeomCollArea, gaiaMeasureLength, gaiaGeomCollLength

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollOverlaps	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial relationship evalution: Overlaps.

Parameters

geom1	the first Geometry object to be evaluated
geom2	the second Geometry object to be evaluated

Returns

0 if false: any other value if true

See also

gaiaGeomCollOverlaps_r, gaiaGeomCollPreparedOverlaps, gaiaGeomCollEquals, gaiaGeomCollDisjoint, gaiaGeomCollIntersects, gaiaGeomCollCrosses, gaiaGeomCollContains, gaiaGeomCollWithin, gaiaGeomCollTouches, gaiaGeomCollRelate

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollOverlaps_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial relationship evalution: Overlaps.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object to be evaluated
geom2	the second Geometry object to be evaluated

Returns

0 if false: any other value if true

See also

gaiaGeomCollOverlaps, gaiaGeomCollPreparedOverlaps, gaiaGeomCollEquals, gaiaGeomCollDisjoint, gaiaGeomCollIntersects, gaiaGeomCollCrosses, gaiaGeomCollContains, gaiaGeomCollWithin, gaiaGeomCollTouches, gaiaGeomCollRelate

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollPreparedContains	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		unsigned char *	blob1,
		int	size1,
		gaiaGeomCollPtr	geom2,
		unsigned char *	blob2,
		int	size2
	)

Spatial relationship evalution: Contains (GEOSPreparedGeometry)

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object to be evaluated
blob1	the BLOB corresponding to the first Geometry
size1	the size (in bytes) of the first BLOB
geom2	the second Geometry object to be evaluated
blob2	the BLOB corresponding to the second Geometry
size2	the size (in bytes) of the second BLOB

Returns

0 if false: any other value if true

See also

gaiaGeomCollContains, gaiaGeomCollContains_r

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollPreparedCoveredBy	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		unsigned char *	blob1,
		int	size1,
		gaiaGeomCollPtr	geom2,
		unsigned char *	blob2,
		int	size2
	)

Topology check: test if a Geometry is covered by another one (GEOSPreparedGeometry)

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	pointer to first input Geometry object.
blob1	the BLOB corresponding to the first Geometry
size1	the size (in bytes) of the first BLOB
geom2	pointer to second input Geometry object.
blob2	the BLOB corresponding to the second Geometry
size2	the size (in bytes) of the second BLOB

Returns

0 if false; any other value if geom2 is spatially covered by geom1.

See also

gaiaGeomCollCoveredBy, gaiaGeomCollCoveredBy_r, gaiaGeomCollCovers

Note

reentrant and thread-safe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE int gaiaGeomCollPreparedCovers	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		unsigned char *	blob1,
		int	size1,
		gaiaGeomCollPtr	geom2,
		unsigned char *	blob2,
		int	size2
	)

Topology check: test if a Geometry covers another one (GEOSPreparedGeometry)

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	pointer to first input Geometry object.
blob1	the BLOB corresponding to the first Geometry
size1	the size (in bytes) of the first BLOB
geom2	pointer to second input Geometry object.
blob2	the BLOB corresponding to the second Geometry
size2	the size (in bytes) of the second BLOB

Returns

0 if false; any other value if geom1 spatially covers geom2.

Note

reentrant and thread-safe.

See also

gaiaGeomCollCovers, gaiaGeomCollCovers_r

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE int gaiaGeomCollPreparedCrosses	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		unsigned char *	blob1,
		int	size1,
		gaiaGeomCollPtr	geom2,
		unsigned char *	blob2,
		int	size2
	)

Spatial relationship evalution: Crosses (GEOSPreparedGeometry)

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object to be evaluated
blob1	the BLOB corresponding to the first Geometry
size1	the size (in bytes) of the first BLOB
geom2	the second Geometry object to be evaluated
blob2	the BLOB corresponding to the second Geometry
size2	the size (in bytes) of the second BLOB

Returns

0 if false: any other value if true

Note

reentrant and thread-safe.

See also

gaiaGeomCollCrosses, gaiaGeomCollCrosses_r

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollPreparedDisjoint	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		unsigned char *	blob1,
		int	size1,
		gaiaGeomCollPtr	geom2,
		unsigned char *	blob2,
		int	size2
	)

Spatial relationship evalution: Disjoint (GEOSPreparedGeometry)

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object to be evaluated
blob1	the BLOB corresponding to the first Geometry
size1	the size (in bytes) of the first BLOB
geom2	the second Geometry object to be evaluated
blob2	the BLOB corresponding to the second Geometry
size2	the size (in bytes) of the second BLOB

Returns

0 if false: any other value if true

See also

gaiaGeomCollDisjoint, gaiaGeomCollDisjoint_r

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollPreparedIntersects	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		unsigned char *	blob1,
		int	size1,
		gaiaGeomCollPtr	geom2,
		unsigned char *	blob2,
		int	size2
	)

Spatial relationship evalution: Intersects (GEOSPreparedGeometry)

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object to be evaluated
blob1	the BLOB corresponding to the first Geometry
size1	the size (in bytes) of the first BLOB
geom2	the second Geometry object to be evaluated
blob2	the BLOB corresponding to the second Geometry
size2	the size (in bytes) of the second BLOB

Returns

0 if false: any other value if true

See also

gaiaGeomCollIntersects, gaiaGeomCollIntersects_r

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollPreparedOverlaps	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		unsigned char *	blob1,
		int	size1,
		gaiaGeomCollPtr	geom2,
		unsigned char *	blob2,
		int	size2
	)

Spatial relationship evalution: Overlaps (GEOSPreparedGeometry)

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object to be evaluated
blob1	the BLOB corresponding to the first Geometry
size1	the size (in bytes) of the first BLOB
geom2	the second Geometry object to be evaluated
blob2	the BLOB corresponding to the second Geometry
size2	the size (in bytes) of the second BLOB

Returns

0 if false: any other value if true

See also

gaiaGeomCollOverlaps, gaiaGeomCollOverlaps_r

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollPreparedTouches	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		unsigned char *	blob1,
		int	size1,
		gaiaGeomCollPtr	geom2,
		unsigned char *	blob2,
		int	size2
	)

Spatial relationship evalution: Touches (GEOSPreparedGeometry)

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object to be evaluated
blob1	the BLOB corresponding to the first Geometry
size1	the size (in bytes) of the first BLOB
geom2	the second Geometry object to be evaluated
blob2	the BLOB corresponding to the second Geometry
size2	the size (in bytes) of the second BLOB

Returns

0 if false: any other value if true

See also

gaiaGeomCollTouches, gaiaGeomCollTouches_r

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollPreparedWithin	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		unsigned char *	blob1,
		int	size1,
		gaiaGeomCollPtr	geom2,
		unsigned char *	blob2,
		int	size2
	)

Spatial relationship evalution: Within (GEOSPreparedGeometry)

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object to be evaluated
blob1	the BLOB corresponding to the first Geometry
size1	the size (in bytes) of the first BLOB
geom2	the second Geometry object to be evaluated
blob2	the BLOB corresponding to the second Geometry
size2	the size (in bytes) of the second BLOB

Returns

0 if false: any other value if true

See also

gaiaGeomCollWithin, gaiaGeomCollWithin_r

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollRelate	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2,
		const char *	pattern
	)

Spatial relationship evalution: Relate.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object to be evaluated
geom2	the second Geometry object to be evaluated
pattern	intersection matrix pattern [DE-9IM]

Returns

0 if false: any other value if true

See also

gaiaGeomCollRelate_r, gaiaGeomCollEquals, gaiaGeomCollDisjoint, gaiaGeomCollIntersects, gaiaGeomCollOverlaps, gaiaGeomCollCrosses, gaiaGeomCollContains, gaiaGeomCollWithin, gaiaGeomCollRelate

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollRelate_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2,
		const char *	pattern
	)

Spatial relationship evalution: Relate.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object to be evaluated
geom2	the second Geometry object to be evaluated
pattern	intersection matrix pattern [DE-9IM]

Returns

0 if false: any other value if true

See also

gaiaGeomCollRelate, gaiaGeomCollEquals, gaiaGeomCollDisjoint, gaiaGeomCollIntersects, gaiaGeomCollOverlaps, gaiaGeomCollCrosses, gaiaGeomCollContains, gaiaGeomCollWithin, gaiaGeomCollRelate

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaGeomCollSimplify	(	gaiaGeomCollPtr	geom,
		double	tolerance
	)

Spatial operator: Simplify.

Parameters

geom	the input Geometry object
tolerance	approximation threshold

Returns

the pointer to newly created Geometry object representing the simplified Geometry [applying the Douglas-Peucker algorithm]: NULL on failure.

See also

gaiaGeomCollSimplify_r, gaiaFreeGeomColl, gaiaGeomCollSimplifyPreserveTopology

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaGeomCollSimplify()
not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaGeomCollSimplify_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom,
		double	tolerance
	)

Spatial operator: Simplify.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	the input Geometry object
tolerance	approximation threshold

Returns

the pointer to newly created Geometry object representing the simplified Geometry [applying the Douglas-Peucker algorithm]: NULL on failure.

See also

gaiaGeomCollSimplify, gaiaFreeGeomColl, gaiaGeomCollSimplifyPreserveTopology

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaGeomCollSimplify_r()
reentrant and thread safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaGeomCollSimplifyPreserveTopology	(	gaiaGeomCollPtr	geom,
		double	tolerance
	)

Spatial operator: Simplify [preserving topology].

Parameters

geom	the input Geometry object
tolerance	approximation threshold

Returns

the pointer to newly created Geometry object representing the simplified Geometry [applying the Douglas-Peucker algorithm]: NULL on failure.

See also

gaiaGeomCollSimplifyPreserveTopology_r, gaiaFreeGeomColl, gaiaGeomCollSimplify

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaGeomCollSimplify()
not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaGeomCollSimplifyPreserveTopology_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom,
		double	tolerance
	)

Spatial operator: Simplify [preserving topology].

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	the input Geometry object
tolerance	approximation threshold

Returns

the pointer to newly created Geometry object representing the simplified Geometry [applying the Douglas-Peucker algorithm]: NULL on failure.

See also

gaiaGeomCollSimplifyPreserveTopology, gaiaFreeGeomColl, gaiaGeomCollSimplify

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaGeomCollSimplify_r()
reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollTouches	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial relationship evalution: Touches.

Parameters

geom1	the first Geometry object to be evaluated
geom2	the second Geometry object to be evaluated

Returns

0 if false: any other value if true

See also

gaiaGeomCollTouches_r, gaiaGeomCollPreparedTouches, gaiaGeomCollEquals, gaiaGeomCollDisjoint, gaiaGeomCollIntersects, gaiaGeomCollOverlaps, gaiaGeomCollCrosses, gaiaGeomCollContains, gaiaGeomCollWithin, gaiaGeomCollRelate

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollTouches_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial relationship evalution: Touches.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object to be evaluated
geom2	the second Geometry object to be evaluated

Returns

0 if false: any other value if true

See also

gaiaGeomCollTouches, gaiaGeomCollPreparedTouches, gaiaGeomCollEquals, gaiaGeomCollDisjoint, gaiaGeomCollIntersects, gaiaGeomCollOverlaps, gaiaGeomCollCrosses, gaiaGeomCollContains, gaiaGeomCollWithin, gaiaGeomCollRelate

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollWithin	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial relationship evalution: Within.

Parameters

geom1	the first Geometry object to be evaluated
geom2	the second Geometry object to be evaluated

Returns

0 if false: any other value if true

See also

gaiaGeomCollWithin_r, gaiaGeomCollPreparedWithin, gaiaGeomCollEquals, gaiaGeomCollDisjoint, gaiaGeomCollIntersects, gaiaGeomCollOverlaps, gaiaGeomCollCrosses, gaiaGeomCollContains, gaiaGeomCollTouches, gaiaGeomCollRelate

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGeomCollWithin_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial relationship evalution: Within.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object to be evaluated
geom2	the second Geometry object to be evaluated

Returns

0 if false: any other value if true

See also

gaiaGeomCollWithin, gaiaGeomCollPreparedWithin, gaiaGeomCollEquals, gaiaGeomCollDisjoint, gaiaGeomCollIntersects, gaiaGeomCollOverlaps, gaiaGeomCollCrosses, gaiaGeomCollContains, gaiaGeomCollTouches, gaiaGeomCollRelate

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaGeometryDifference	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial operator: Difference.

Parameters

geom1	the first Geometry object
geom2	the second Geometry object

Returns

the pointer to newly created Geometry object representing the geometry Difference of both input Geometries: NULL on failure.

See also

gaiaGeometryDifference_r, gaiaGeometrySymDifference, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaGeometryDifference()
not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaGeometryDifference_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial operator: Difference.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object
geom2	the second Geometry object

Returns

the pointer to newly created Geometry object representing the geometry Difference of both input Geometries: NULL on failure.

See also

gaiaGeometryDifference, gaiaGeometrySymDifference, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaGeometryDifference_r()
reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaGeometryIntersection	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial operator: Intersection.

Parameters

geom1	the first Geometry object
geom2	the second Geometry object

Returns

the pointer to newly created Geometry object representing the geometry Intersection of both input Geometries: NULL on failure.

See also

gaiaGeometryIntersection_r, gaiaFreeGeomColl, gaiaGeometryUnion, gaiaGeometryDifference, gaiaGeometrySymDifference, gaiaBoundary

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaGeometryIntersection()
not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaGeometryIntersection_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial operator: Intersection.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object
geom2	the second Geometry object

Returns

the pointer to newly created Geometry object representing the geometry Intersection of both input Geometries: NULL on failure.

See also

gaiaGeometryIntersection, gaiaFreeGeomColl, gaiaGeometryUnion, gaiaGeometryDifference, gaiaGeometrySymDifference, gaiaBoundary

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaGeometryIntersection_r()
reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaGeometrySymDifference	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial operator: SymDifference.

Parameters

geom1	the first Geometry object
geom2	the second Geometry object

Returns

the pointer to newly created Geometry object representing the geometry SymDifference of both input Geometries: NULL on failure.

See also

gaiaGeometrySymDifference_r, gaiaGeometryDifference, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaGeometrySymDifference()
not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaGeometrySymDifference_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial operator: SymDifference.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object
geom2	the second Geometry object

Returns

the pointer to newly created Geometry object representing the geometry SymDifference of both input Geometries: NULL on failure.

See also

gaiaGeometrySymDifference, gaiaGeometryDifference, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaGeometrySymDifference_r()
reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaGeometryUnion	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial operator: Union.

Parameters

geom1	the first Geometry object
geom2	the second Geometry object

Returns

the pointer to newly created Geometry object representing the geometry Union of both input Geometries: NULL on failure.

See also

gaiaGeometryUnion_r, gaiaFreeGeomColl, gaiaUnaryUnion, gaiaUnionCascaded

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaGeometryUnion()
not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaGeometryUnion_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial operator: Union.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	the first Geometry object
geom2	the second Geometry object

Returns

the pointer to newly created Geometry object representing the geometry Union of both input Geometries: NULL on failure.

See also

gaiaGeometryUnion, gaiaFreeGeomColl, gaiaUnaryUnion, gaiaUnionCascaded

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaGeometryUnion_r()
reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE const char* gaiaGetGeosAuxErrorMsg

(

void

)

Return the latest GEOS (auxiliary) error message (if any)

Returns

the latest GEOS (auxiliary) error message: an empty string if no error was previoysly found.

See also

gaiaGetGeosAuxErrorMsg_r, gaiaResetGeosMsg, gaiaGetGeosErrorMsg, gaiaGetGeosWarningMsg, gaiaSetGeosErrorMsg, gaiaSetGeosWarningMsg, gaiaSetGeosAuxErrorMsg

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE const char* gaiaGetGeosAuxErrorMsg_r

(

const void *

p_cache

)

Return the latest GEOS (auxiliary) error message (if any)

Parameters

p_cache

a memory pointer returned by spatialite_alloc_connection()

Returns

the latest GEOS (auxiliary) error message: an empty string if no error was previoysly found.

See also

gaiaGetGeosAuxErrorMsg, gaiaResetGeosMsg, gaiaGetGeosErrorMsg, gaiaGetGeosWarningMsg, gaiaSetGeosErrorMsg, gaiaSetGeosWarningMsg, gaiaSetGeosAuxErrorMsg

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE const char* gaiaGetGeosErrorMsg

(

void

)

Return the latest GEOS error message (if any)

Returns

the latest GEOS error message: an empty string if no error was previoysly found.

See also

gaiaGetGeosErrorMsg_r, gaiaResetGeosMsg, gaiaGetGeosWarningMsg, gaiaGetGeosAuxErrorMsg, gaiaSetGeosErrorMsg, gaiaSetGeosWarningMsg, gaiaSetGeosAuxErrorMsg, gaiaCriticalPointFromGEOSmsg

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE const char* gaiaGetGeosErrorMsg_r

(

const void *

p_cache

)

Return the latest GEOS error message (if any)

Parameters

p_cache

a memory pointer returned by spatialite_alloc_connection()

Returns

the latest GEOS error message: an empty string if no error was previoysly found.

See also

gaiaGetGeosErrorMsg, gaiaResetGeosMsg, gaiaGetGeosWarningMsg, gaiaGetGeosAuxErrorMsg, gaiaSetGeosErrorMsg, gaiaSetGeosWarningMsg, gaiaSetGeosAuxErrorMsg, gaiaCriticalPointFromGEOSmsg

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE const char* gaiaGetGeosWarningMsg

(

void

)

Return the latest GEOS warning message (if any)

Returns

the latest GEOS warning message: an empty string if no warning was previoysly found.

See also

gaiaGetGeosWarningMsg_r, gaiaResetGeosMsg, gaiaGetGeosErrorMsg, gaiaGetGeosAuxErrorMsg, gaiaSetGeosErrorMsg, gaiaSetGeosWarningMsg, gaiaSetGeosAuxErrorMsg, gaiaCriticalPointFromGEOSmsg

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE const char* gaiaGetGeosWarningMsg_r

(

const void *

p_cache

)

Return the latest GEOS warning message (if any)

Parameters

p_cache

a memory pointer returned by spatialite_alloc_connection()

Returns

the latest GEOS warning message: an empty string if no warning was previoysly found.

See also

gaiaGetGeosWarningMsg, gaiaResetGeosMsg, gaiaGetGeosErrorMsg, gaiaGetGeosAuxErrorMsg, gaiaSetGeosErrorMsg, gaiaSetGeosWarningMsg, gaiaSetGeosAuxErrorMsg, gaiaCriticalPointFromGEOSmsg

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE const char* gaiaGetLwGeomErrorMsg

(

void

)

Return the latest LWGEOM error message (if any)

Returns

the latest LWGEOM error message: an empty string if no error was previoysly found.

Note

not reentrant and thread unsafe.

See also

gaiaResetLwGeomMsg, gaiaGetLwGeomWarningMsg, gaiaSetLwGeomErrorMsg, gaiaSetLwGeomWarningMsg

Remarks

LWGEOM support required.

GAIAGEO_DECLARE const char* gaiaGetLwGeomWarningMsg

(

void

)

Return the latest LWGEOM warning message (if any)

Returns

the latest LWGEOM warning message: an empty string if no warning was previoysly found.

See also

gaiaResetLwGeomMsg, gaiaGetLwGeomErrorMsg, gaiaSetLwGeomErrorMsg, gaiaSetLwGeomWarningMsg

Note

not reentrant and thread unsafe.

Remarks

LWGEOM support required.

GAIAGEO_DECLARE int gaiaGetPointOnSurface	(	gaiaGeomCollPtr	geom,
		double *	x,
		double *	y
	)

Spatial operator: PointOnSurface.

Parameters

geom	pointer to Geometry object.
x	on completion this variable will contain the Point X coordinate
y	on completion this variable will contain the Point Y coordinate

Returns

0 on failure: any other value on success

See also

gaiaGetPointOnSurface_r

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaGetPointOnSurface_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom,
		double *	x,
		double *	y
	)

Spatial operator: PointOnSurface.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	pointer to Geometry object.
x	on completion this variable will contain the Point X coordinate
y	on completion this variable will contain the Point Y coordinate

Returns

0 on failure: any other value on success

See also

gaiaGetPointOnSurface

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaHausdorffDistance	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2,
		double *	dist
	)

Calculates the Hausdorff distance intercurring between two Geometry objects.

Parameters

geom1	pointer to first Geometry object
geom2	pointer to second Geometry object
dist	on completion this variable will contain the calculated Hausdorff distance

Returns

0 on failure: any other value on success.

See also

gaiaHausdorffDistance_r

Note

not reentrant and thread unsafe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE int gaiaHausdorffDistance_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2,
		double *	dist
	)

Calculates the Hausdorff distance intercurring between two Geometry objects.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	pointer to first Geometry object
geom2	pointer to second Geometry object
dist	on completion this variable will contain the calculated Hausdorff distance

Returns

0 on failure: any other value on success.

See also

gaiaHausdorffDistance

Note

reentrant and thread-safe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaHexagonalGrid	(	gaiaGeomCollPtr	geom,
		double	origin_x,
		double	origin_y,
		double	size,
		int	only_edges
	)

Utility function: HexagonalGrid.

Parameters

geom	the Geometry to be covered by the Grid.
origin_x	the X ccordinate identifying the Grid Origin.
origin_y	the Y coordinate identifiying the Grid Origin.
size	the Grid cell-side size.
only_edges	if non-zero will return a MULTILINESTRING, otherwise it will return a MULTIPOLYGON containing hexagonal POLYGONs.

Returns

the pointer to newly created Geometry object: NULL on failure.
this function will always return a MultiPolygon
NULL will be returned if any argument is invalid.

See also

gaiaGexagonalGrid_r, gaiaFreeGeomColl, gaiaSquareGrid, gaiaTriangularGrid

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaHexagonalGrid()
not reentrant and thread unsafe.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaHexagonalGrid_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom,
		double	origin_x,
		double	origin_y,
		double	size,
		int	only_edges
	)

Utility function: HexagonalGrid.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	the Geometry to be covered by the Grid.
origin_x	the X ccordinate identifying the Grid Origin.
origin_y	the Y coordinate identifiying the Grid Origin.
size	the Grid cell-side size.
only_edges	if non-zero will return a MULTILINESTRING, otherwise it will return a MULTIPOLYGON containing hexagonal POLYGONs.

Returns

the pointer to newly created Geometry object: NULL on failure.
this function will always return a MultiPolygon
NULL will be returned if any argument is invalid.

See also

gaiaGexagonalGrid, gaiaFreeGeomColl, gaiaSquareGrid, gaiaTriangularGrid

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaHexagonalGrid_r()
reentrant and thread-safe.

GAIAGEO_DECLARE int gaiaIsClosed

(

gaiaLinestringPtr

line

)

Checks if a Linestring object represents an OGC Closed Geometry.

This function only works on a single linestring - if you pass in a multi-line linestring geometry, it will return 0 (false). See gaiaIsClosedGeom for an alternative.

Parameters

line	pointer to Linestring object.

Returns

0 if false; any other value if true

See also

gaiaIsSimple, gaiaIsRing, gaiaIsValid, gaiaIsClosedGeom

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaIsClosedGeom

(

gaiaGeomCollPtr

geom

)

Checks if a Geometry object represents an OGC Closed Linestring.

Parameters

geom	pointer to Geometry object.

Returns

0 if false; any other value if true

See also

gaiaIsClosedGeom_r, gaiaIsSimple, gaiaIsRing, gaiaIsValid, gaiaIsClosed

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaIsClosedGeom_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom
	)

Checks if a Geometry object represents an OGC Closed Linestring.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	pointer to Geometry object.

Returns

0 if false; any other value if true

See also

gaiaIsClosedGeom, gaiaIsSimple, gaiaIsRing, gaiaIsValid, gaiaIsClosed

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaIsRing

(

gaiaLinestringPtr

line

)

Checks if a Linestring object represents an OGC Ring Geometry.

Parameters

line	pointer to Geometry object.

Returns

0 if false; any other value if true

See also

gaiaIsRing_r, gaiaIsSimple, gaiaIsClosed, gaiaIsValid

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaIsRing_r	(	const void *	p_cache,
		gaiaLinestringPtr	line
	)

Checks if a Linestring object represents an OGC Ring Geometry.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
line	pointer to Geometry object.

Returns

0 if false; any other value if true

See also

gaiaIsRing, gaiaIsSimple, gaiaIsClosed, gaiaIsValid

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaIsSimple

(

gaiaGeomCollPtr

geom

)

Checks if a Geometry object represents an OGC Simple Geometry.

Parameters

geom	pointer to Geometry object.

Returns

0 if false; any other value if true

See also

gaiaIsSimple_r, gaiaIsClosed, gaiaIsRing, gaiaIsValid

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaIsSimple_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom
	)

Checks if a Geometry object represents an OGC Simple Geometry.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	pointer to Geometry object.

Returns

0 if false; any other value if true

See also

gaiaIsSimple, gaiaIsClosed, gaiaIsRing, gaiaIsValid

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaIsValid

(

gaiaGeomCollPtr

geom

)

Checks if a Geometry object represents an OGC Valid Geometry.

Parameters

geom	pointer to Geometry object.

Returns

0 if false; any other value if true

See also

gaiaIsValid_r, gaiaIsSimple, gaiaIsClosed, gaiaIsRing, gaiaIsValidReason

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

Examples:

demo2.c.

GAIAGEO_DECLARE int gaiaIsValid_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom
	)

Checks if a Geometry object represents an OGC Valid Geometry.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	pointer to Geometry object.

Returns

0 if false; any other value if true

See also

gaiaIsValid, gaiaIsSimple, gaiaIsClosed, gaiaIsRing, gaiaIsValidReason_r

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaIsValidDetail

(

gaiaGeomCollPtr

geom

)

return a Geometry detail causing a Geometry to be invalid

Parameters

geom	pointer to the Geometry object to be validated.

Returns

pointer to a Geometry object causing invalidity, or NULL.

See also

gaiaIsValid, gaiaIsValidReason, gaiaIsValidDetail_r

Note

you are responsible to destroy the returned Geometry
not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaIsValidDetail_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom
	)

return a Geometry detail causing a Geometry to be invalid

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	pointer to the Geometry object to be validated.

Returns

pointer to a Geometry object causing invalidity, or NULL.

See also

gaiaIsValid_r, gaiaIsValidReason_r, gaiaIsValidDetail

Note

you are responsible to destroy the returned Geometry
reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE char* gaiaIsValidReason

(

gaiaGeomCollPtr

geom

)

return a TEXT string stating if a Geometry is valid and if not valid, a reason why

Parameters

geom	pointer to the Geometry object to be validated.

Returns

a text string.

See also

gaiaIsValid, gaiaIsValidReason_r, gaiaIsValidDetail

Note

you are responsible to free() the returned text string
not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE char* gaiaIsValidReason_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom
	)

return a TEXT string stating if a Geometry is valid and if not valid, a reason why

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	pointer to the Geometry object to be validated.

Returns

a text string.

See also

gaiaIsValid_r, gaiaIsValidReason, gaiaIsValidDetail_r

Note

you are responsible to free() the returned text string
reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaLineInterpolateEquidistantPoints	(	gaiaGeomCollPtr	ln_geom,
		double	distance
	)

Spatial operator: Line Interpolate Equidistant Points.

Parameters

ln_geom	the input Geometry object [expected to be of lineal type]
distance	regular distance between interpolated points

Returns

the pointer to newly created Geometry object representing a MultiPoint; such MultiPoint always supports the M coordinate (the corresponding value representing the progressive distance for each interpolated Point). individual Points will be regularly spaced by the given distance: NULL on failure.

See also

gaiaLineInterpolateEquidistantPoints_r, gaiaLineInterpolatePoint, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaLineInterpolateEquidistantPoints()
not reentrant and thread unsafe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaLineInterpolateEquidistantPoints_r	(	const void *	p_cache,
		gaiaGeomCollPtr	ln_geom,
		double	distance
	)

Spatial operator: Line Interpolate Equidistant Points.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
ln_geom	the input Geometry object [expected to be of lineal type]
distance	regular distance between interpolated points

Returns

the pointer to newly created Geometry object representing a MultiPoint; such MultiPoint always supports the M coordinate (the corresponding value representing the progressive distance for each interpolated Point). individual Points will be regularly spaced by the given distance: NULL on failure.

See also

gaiaLineInterpolateEquidistantPoints, gaiaLineInterpolatePoint, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaLineInterpolateEquidistantPoints_r()
reentrant and thread-safe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaLineInterpolatePoint	(	gaiaGeomCollPtr	ln_geom,
		double	fraction
	)

Spatial operator: Line Interpolate Point.

Parameters

ln_geom	the input Geometry object [expected to be of lineal type]
fraction	total length fraction [in the range 0.0 / 1.0]

Returns

the pointer to newly created Geometry object representing a Point laying on the input Geometry and positioned at the given length fraction: NULL on failure.

See also

gaiaLineInterpolatePoint_r, gaiaLineInterpolateEquidistantPoints, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaLineInterpolatePoint()
not reentrant and thread unsafe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaLineInterpolatePoint_r	(	const void *	p_cache,
		gaiaGeomCollPtr	ln_geom,
		double	fraction
	)

Spatial operator: Line Interpolate Point.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
ln_geom	the input Geometry object [expected to be of lineal type]
fraction	total length fraction [in the range 0.0 / 1.0]

Returns

the pointer to newly created Geometry object representing a Point laying on the input Geometry and positioned at the given length fraction: NULL on failure.

See also

gaiaLineInterpolatePoint, gaiaLineInterpolateEquidistantPoints, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaLineInterpolatePoint_r()
reentrant and thread-safe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE double gaiaLineLocatePoint	(	gaiaGeomCollPtr	ln_geom,
		gaiaGeomCollPtr	pt_geom
	)

Determines the location of the closest Point on Linestring to the given Point.

Parameters

ln_geom	pointer to first input Geometry object [expected to be of the lineal type].
pt_geom	pointer to second input Geometry object [expected to be a Point].

Returns

the fraction [in the range 0.0 / 1.0] of ln_geom total length where the closest Point to pt_geom lays.

See also

gaiaLineLocatePoint_r

Note

not reentrant and thread unsafe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE double gaiaLineLocatePoint_r	(	const void *	p_cache,
		gaiaGeomCollPtr	ln_geom,
		gaiaGeomCollPtr	pt_geom
	)

Determines the location of the closest Point on Linestring to the given Point.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
ln_geom	pointer to first input Geometry object [expected to be of the lineal type].
pt_geom	pointer to second input Geometry object [expected to be a Point].

Returns

the fraction [in the range 0.0 / 1.0] of ln_geom total length where the closest Point to pt_geom lays.

See also

gaiaLineLocatePoint

Note

reentrant and thread-safe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaLineMerge

(

gaiaGeomCollPtr

geom

)

Spatial operator: Line Merge.

Parameters

geom	pointer to input Geometry object.

Returns

the pointer to newly created Geometry object; NULL on failure.
if possible, this representing a reassembled Linestring or MultiLinestring.

See also

gaiaLineMerge_r, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaLineMerge()
not reentrant and thread unsafe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaLineMerge_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom
	)

Spatial operator: Line Merge.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	pointer to input Geometry object.

Returns

the pointer to newly created Geometry object; NULL on failure.
if possible, this representing a reassembled Linestring or MultiLinestring.

See also

gaiaLineMerge, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaLineMerge_r()
reentrant and thread-safe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaLinesCutAtNodes	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial operator: Line Cut At Nodes.

Parameters

geom1	pointer to input Geometry object [Linestring or MultiLinestring].
geom2	pointer to input Geometry object [Point or MultiPoint].

Returns

the pointer to newly created Geometry object; NULL on failure.
if possible, any input Linestring will be split accordingly to given Node(s): no point will be interpolated, existing Linestring Vertices will be evaluated.

See also

gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaLinesCutAtNodes()

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaLineSubstring	(	gaiaGeomCollPtr	ln_geom,
		double	start_fraction,
		double	end_fraction
	)

Spatial operator: Line Substring.

Parameters

ln_geom	the input Geometry object [expected to be of lineal type]
start_fraction	substring start, expressed as total length fraction [in the range 0.0 / 1.0]
end_fraction	substring end, expressed as total length fraction

Returns

the pointer to newly created Geometry object representing a Linestring laying on the input Geometry.
this Linestring will begin (and stop) at given total length fractions. NULL on failure.

See also

gaiaLineSubstring_r, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaLineSubstring()
not reentrant and thread unsafe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaLineSubstring_r	(	const void *	p_cache,
		gaiaGeomCollPtr	ln_geom,
		double	start_fraction,
		double	end_fraction
	)

Spatial operator: Line Substring.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
ln_geom	the input Geometry object [expected to be of lineal type]
start_fraction	substring start, expressed as total length fraction [in the range 0.0 / 1.0]
end_fraction	substring end, expressed as total length fraction

Returns

the pointer to newly created Geometry object representing a Linestring laying on the input Geometry.
this Linestring will begin (and stop) at given total length fractions. NULL on failure.

See also

gaiaLineSubstring, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaLineSubstring_r()
reentrant and thread-safe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaMakeValid

(

gaiaGeomCollPtr

geom

)

Utility function: MakeValid.

Parameters

geom	the input Geometry object.

Returns

the pointer to newly created Geometry object: NULL on failure.
this function will attempt to create a valid representation of a given invalid geometry without loosing any of the input vertices.
Already-valid geometries are returned without further intervention.
NULL will be returned if the passed argument is invalid.

See also

gaiaFreeGeomColl, gaiaMakeValidDiscarded

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaMakeValid()

Remarks

LWGEOM support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaMakeValidDiscarded

(

gaiaGeomCollPtr

geom

)

Utility function: MakeValidDiscarded.

Parameters

geom	the input Geometry object.

Returns

the pointer to newly created Geometry object: NULL on failure.
this function will attempt to collect any invalid item (offending geometries) discarded by gaiaMakeValid while building a valid Geometry.
Saving any discarded item could be useful for a finer (manual) adjustment.
NULL will be returned if gaiaMakeValid hasn't identified any offending item to be discarded during the validation.

See also

gaiaFreeGeomColl, gaiaMakeValid

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaMakeValidDiscarded()

Remarks

LWGEOM support required.

GAIAGEO_DECLARE int gaiaMaxDistance	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2,
		double *	dist
	)

Calculates the maximum 2D distance intercurring between two Geometry objects.

Parameters

geom1	the first Geometry object
geom2	the second Geometry object
dist	on completion this variable will contain the calculated distance

Returns

0 on failure: any other value on success.

See also

gaiaGeomCollDistance, gaia3DDistance, gaia3DMaxDistance

Note

this function computes the 2D maximum cartesian distance (Z is always ignored)

Remarks

LWGEOM support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaNodeLines

(

gaiaGeomCollPtr

input

)

Utility function: re-noding lines.

Parameters

input

the input Geometry object.

Returns

the pointer to newly created Geometry object: NULL on failure.
The function fully nodes a set of linestrings, using the least nodes preserving all the input ones.

See also

gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaNode()

Remarks

LWGEOM support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaOffsetCurve	(	gaiaGeomCollPtr	geom,
		double	radius,
		int	points,
		int	left_right
	)

Spatial operator: Offset Curve.

Parameters

geom	the input Geometry object
radius	the buffer's radius
points	number of points (aka vertices) to be used in order to approximate a circular arc.
left_right	if set to 1 the left-sided OffsetCurve will be returned; otherwise the right-sided one.

Returns

the pointer to newly created Geometry object representing the OffsetCurve of input Geometry: NULL on failure.

See also

gaiaOffsetCurve_r, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaOffsetCurve()
not reentrant and thread unsafe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaOffsetCurve_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom,
		double	radius,
		int	points,
		int	left_right
	)

Spatial operator: Offset Curve.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	the input Geometry object
radius	the buffer's radius
points	number of points (aka vertices) to be used in order to approximate a circular arc.
left_right	if set to 1 the left-sided OffsetCurve will be returned; otherwise the right-sided one.

Returns

the pointer to newly created Geometry object representing the OffsetCurve of input Geometry: NULL on failure.

See also

gaiaOffsetCurve, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaOffsetCurve_r()
reentrant and thread-safe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaPolygonize	(	gaiaGeomCollPtr	geom,
		int	force_multi
	)

Attempts to rearrange a generic Geometry object into a Polygon or MultiPolygon.

Parameters

geom	the input Geometry object
force_multi	if not set to 0, then an eventual Polygon will be returned casted to MultiPolygon

Returns

the pointer to newly created Geometry object representing a Polygon or MultiPolygon Geometry: NULL on failure.

See also

gaiaPolygonize_r, gaiaMakePolygon, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaPolygonize()
not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaPolygonize_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom,
		int	force_multi
	)

Attempts to rearrange a generic Geometry object into a Polygon or MultiPolygon.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	the input Geometry object
force_multi	if not set to 0, then an eventual Polygon will be returned casted to MultiPolygon

Returns

the pointer to newly created Geometry object representing a Polygon or MultiPolygon Geometry: NULL on failure.

See also

gaiaPolygonize, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaPolygonize_r()
reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE int gaiaProjectedPoint	(	double	x1,
		double	y1,
		double	a,
		double	b,
		double	distance,
		double	azimuth,
		double *	x2,
		double *	y2
	)

Utility function: ProjectedPoint.

Parameters

x1	the X coordinate of the Start Point.
y1	the Y coordinate of the Start Point.
a	major axis of the reference spheroid.
b	minor axis of the reference spheroid.
distance	a distance expressed in Meters
azimuth	(aka bearing aka heading) expressed in radians; on the clock: 12=0; 3=PI/2; 6=PI; 9=3PI/2.
x2	on completion this variable will contain the the X coordinate of the Projected Point.
y2	on completion this variable will contain the the Y coordinate of the Projected Point.

Returns

0 on failure: any other value on success

Remarks

LWGEOM support required.

GAIAGEO_DECLARE void gaiaResetGeosMsg

(

void

)

Resets the GEOS error and warning messages to an empty state.

See also

gaiaResetGeosMsg_r, gaiaGetGeosErrorMsg, gaiaGetGeosWarningMsg, gaiaGeosAuxErrorMsg, gaiaSetGeosErrorMsg, gaiaSetGeosWarningMsg, gaiaSetGeosAuxErrorMsg

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE void gaiaResetGeosMsg_r

(

const void *

p_cache

)

Resets the GEOS error and warning messages to an empty state.

Parameters

p_cache

a memory pointer returned by spatialite_alloc_connection()

See also

gaiaResetGeosMsg, gaiaGetGeosErrorMsg, gaiaGetGeosWarningMsg, gaiaGeosAuxErrorMsg, gaiaSetGeosErrorMsg, gaiaSetGeosWarningMsg, gaiaSetGeosAuxErrorMsg

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE void gaiaResetLwGeomMsg

(

void

)

Resets the LWGEOM error and warning messages to an empty state.

See also

gaiaGetLwGeomErrorMsg, gaiaGetLwGeomWarningMsg, gaiaSetLwGeomErrorMsg, gaiaSetLwGeomWarningMsg

Note

not reentrant and thread unsafe.

Remarks

LWGEOM support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaSegmentize	(	gaiaGeomCollPtr	geom,
		double	dist
	)

Utility function: Segmentize.

Parameters

geom	the input Geometry object.
dist	the meximum segment length.

Returns

the pointer to newly created Geometry object: NULL on failure.
this function will return a modified geometry having no segment longer than the given distance.
Distance computation is performed in 2d only.
all Points or segments shorter than 'dist' will be returned without further intervention.
NULL will be returned if the passed argument is invalid.

See also

gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaSegmentize()

Remarks

LWGEOM support required.

GAIAGEO_DECLARE void gaiaSetGeosAuxErrorMsg

(

const char *

msg

)

Set the current GEOS (auxiliary) error message.

Parameters

msg	the error message to be set.

See also

gaiaSetAuxErrorMsg_r, gaiaResetGeosMsg, gaiaGetGeosErrorMsg, gaiaGetGeosWarningMsg, gaiaGetGeosAuxErrorMsg, gaiaSetGeosWarningMsg, gaiaSetGeosErrorMsg

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE void gaiaSetGeosAuxErrorMsg_r	(	const void *	p_cache,
		const char *	msg
	)

Set the current GEOS (auxiliary) error message.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
msg	the error message to be set.

See also

gaiaSetAuxErrorMsg, gaiaResetGeosMsg, gaiaGetGeosErrorMsg, gaiaGetGeosWarningMsg, gaiaGetGeosAuxErrorMsg, gaiaSetGeosWarningMsg, gaiaSetGeosErrorMsg

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE void gaiaSetGeosErrorMsg

(

const char *

msg

)

Set the current GEOS error message.

Parameters

msg	the error message to be set.

See also

gaiaSetGeosErrorMsg_r, gaiaResetGeosMsg, gaiaGetGeosErrorMsg, gaiaGetGeosWarningMsg, gaiaGetGeosAuxErrorMsg, gaiaSetGeosWarningMsg, gaiaSetGeosAuxErrorMsg

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE void gaiaSetGeosErrorMsg_r	(	const void *	p_cache,
		const char *	msg
	)

Set the current GEOS error message.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
msg	the error message to be set.

See also

gaiaSetGeosErrorMsg, gaiaResetGeosMsg, gaiaGetGeosErrorMsg, gaiaGetGeosWarningMsg, gaiaGetGeosAuxErrorMsg, gaiaSetGeosWarningMsg, gaiaSetGeosAuxErrorMsg

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE void gaiaSetGeosWarningMsg

(

const char *

msg

)

Set the current GEOS warning message.

Parameters

msg	the warning message to be set.

See also

gaiaSetGeosWarningMsg_r, gaiaResetGeosMsg, gaiaGetGeosErrorMsg, gaiaGetGeosWarningMsg, gaiaGetGeosAuxErrorMsg, gaiaSetGeosErrorMsg, gaiaSetGeosAuxErrorMsg

Note

not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE void gaiaSetGeosWarningMsg_r	(	const void *	p_cache,
		const char *	msg
	)

Set the current GEOS warning message.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
msg	the warning message to be set.

See also

gaiaSetGeosWarningMsg, gaiaResetGeosMsg, gaiaGetGeosErrorMsg, gaiaGetGeosWarningMsg, gaiaGetGeosAuxErrorMsg, gaiaSetGeosErrorMsg, gaiaSetGeosAuxErrorMsg

Note

reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE void gaiaSetLwGeomErrorMsg

(

const char *

msg

)

Set the current LWGEOM error message.

Parameters

msg	the error message to be set.

See also

gaiaResetLwGeomMsg, gaiaGetLwGeomErrorMsg, gaiaGetLwGeomWarningMsg, gaiaSetLwGeomWarningMsg

Note

not reentrant and thread unsafe.

Remarks

LWGEOM support required.

GAIAGEO_DECLARE void gaiaSetLwGeomWarningMsg

(

const char *

msg

)

Set the current LWGEOM warning message.

Parameters

msg	the warning message to be set.

See also

gaiaResetLwGeomMsg, gaiaGetLwGeomErrorMsg, gaiaGetLwGeomWarningMsg, gaiaSetLwGeomErrorMsg

Note

not reentrant and thread unsafe.

Remarks

LWGEOM support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaSharedPaths	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial operator: Shared Paths.

Parameters

geom1	pointer to first Geometry object
geom2	pointer to second Geometry object

Returns

the pointer to newly created Geometry object representing any Share Path common to both input geometries: NULL on failure.

See also

gaiaSharedPaths_r, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaSharedPaths()
not reentrant and thread unsafe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaSharedPaths_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial operator: Shared Paths.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	pointer to first Geometry object
geom2	pointer to second Geometry object

Returns

the pointer to newly created Geometry object representing any Share Path common to both input geometries: NULL on failure.

See also

gaiaSharedPaths, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaSharedPaths_r()
reentrant and thread-safe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaShortestLine	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial operator: Shortest Line.

Parameters

geom1	pointer to the first Geometry object.
geom2	pointer to the second Geometry object.

Returns

the pointer to newly created Geometry object representing a Linestring; NULL on failure.
the returned Linestring graphically represents the minimum distance intercurrinng between both input geometries.

See also

gaiaShortestLine_r, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaShortestLine()
not reentrant and thread unsafe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaShortestLine_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2
	)

Spatial operator: Shortest Line.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	pointer to the first Geometry object.
geom2	pointer to the second Geometry object.

Returns

the pointer to newly created Geometry object representing a Linestring; NULL on failure.
the returned Linestring graphically represents the minimum distance intercurrinng between both input geometries.

See also

gaiaShortestLine, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaShortestLine_r()
reentrant and thread-safe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaSingleSidedBuffer	(	gaiaGeomCollPtr	geom,
		double	radius,
		int	points,
		int	left_right
	)

Spatial operator: Single Sided Buffer.

Parameters

geom	the input Geometry object
radius	the buffer's radius
points	number of points (aka vertices) to be used in order to approximate a circular arc.
left_right	if set to 1 the left-sided Buffer will be returned; otherwise the right-sided one.

Returns

the pointer to newly created Geometry object representing the single-sided Buffer of input Geometry: NULL on failure.

See also

gaiaSingleSidedBuffer_r, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaSingleSidedBuffer()
not reentrant and thread unsafe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaSingleSidedBuffer_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom,
		double	radius,
		int	points,
		int	left_right
	)

Spatial operator: Single Sided Buffer.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	the input Geometry object
radius	the buffer's radius
points	number of points (aka vertices) to be used in order to approximate a circular arc.
left_right	if set to 1 the left-sided Buffer will be returned; otherwise the right-sided one.

Returns

the pointer to newly created Geometry object representing the single-sided Buffer of input Geometry: NULL on failure.

See also

gaiaSingleSidedBuffer, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaSingleSidedBuffer_r()
reentrant and thread-safe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaSnap	(	gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2,
		double	tolerance
	)

Spatial operator: Snap.

Parameters

geom1	pointer to the first Geometry object.
geom2	pointer to the second Geometry object.
tolerance	approximation factor

Returns

the pointer to newly created Geometry object; NULL on failure.
the returned Geometry represents the first input Geometry (nicely snapped to the second input Geometry, whenever is possible).

See also

gaiaSnap_r, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaSnap()
not reentrant and thread unsafe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaSnap_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom1,
		gaiaGeomCollPtr	geom2,
		double	tolerance
	)

Spatial operator: Snap.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom1	pointer to the first Geometry object.
geom2	pointer to the second Geometry object.
tolerance	approximation factor

Returns

the pointer to newly created Geometry object; NULL on failure.
the returned Geometry represents the first input Geometry (nicely snapped to the second input Geometry, whenever is possible).

See also

gaiaSnap, gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaSnap_r()
reentrant and thread-safe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaSnapToGrid	(	gaiaGeomCollPtr	geom,
		double	origin_x,
		double	origin_y,
		double	origin_z,
		double	origin_m,
		double	size_x,
		double	size_y,
		double	size_z,
		double	size_m
	)

Utility function: SnapToGrid.

Parameters

geom	the input Geometry object.
origin_x	the X ccordinate identifying the Grid Origin.
origin_y	the Y coordinate identifiying the Grid Origin.
origin_z	the Z ccordinate identifying the Grid Origin.
origin_m	the M coordinate identifiying the Grid Origin.
size_x	Grid cell size (X axis).
size_y	Grid cell size (Y axis).
size_z	Grid cell size (Z axis).
size_m	Grid cell size (M axis).

Returns

the pointer to newly created Geometry object: NULL on failure.
this function will return a modified geometry having all points snapped to a regular Grid defined by its origin and cell size.
Consecutive points falling on the same cell will be removed, eventually returning NULL if
output points are not enough to define a geometry of the given type.
Collapsed geometries in a collection are stripped from it.
Specify 0 as size for any dimension you don't want to snap to a grid.
NULL will be returned if the passed argument is invalid.

See also

gaiaFreeGeomColl

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaSnapToGrid()

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaSplit	(	gaiaGeomCollPtr	input,
		gaiaGeomCollPtr	blade
	)

Utility function: Split.

Parameters

input	the input Geometry object.
blade	the blade Geometry object.

Returns

the pointer to newly created Geometry object: NULL on failure.
The function supports splitting a line by point, a line by line, a polygon by line.

See also

gaiaFreeGeomColl, gaiaSplitLeft, gaiaSplitRight

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaSplit()

gaiaSplit will return both the left and the right split halves at the same time.

Remarks

LWGEOM support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaSplitLeft	(	gaiaGeomCollPtr	input,
		gaiaGeomCollPtr	blade
	)

Utility function: SplitLeft.

Parameters

input	the input Geometry object.
blade	the blade Geometry object.

Returns

the pointer to newly created Geometry object: NULL on failure.
The function supports splitting a line by point, a line by line, a polygon by line.

See also

gaiaFreeGeomColl, gaiaSplit, gaiaSplitRight

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaSplitLeft()

gaiaSplitLeft will only return the left split half; NULL may be eventually returned if empty.

Remarks

LWGEOM support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaSplitRight	(	gaiaGeomCollPtr	input,
		gaiaGeomCollPtr	blade
	)

Utility function: SplitRight.

Parameters

input	the input Geometry object.
blade	the blade Geometry object.

Returns

the pointer to newly created Geometry object: NULL on failure.
The function supports splitting a line by point, a line by line, a polygon by line.

See also

gaiaFreeGeomColl, gaiaSplit, gaiaSplitLeft

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaSplitRight()

gaiaSplitLeft will only return the right split half; NULL may be eventually returned if empty.

Remarks

LWGEOM support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaSquareGrid	(	gaiaGeomCollPtr	geom,
		double	origin_x,
		double	origin_y,
		double	size,
		int	only_edges
	)

Utility function: SquareGrid.

Parameters

geom	the Geometry to be covered by the Grid.
origin_x	the X ccordinate identifying the Grid Origin.
origin_y	the Y coordinate identifiying the Grid Origin.
size	the Grid cell-side size.
only_edges	if non-zero will return a MULTILINESTRING, otherwise it will return a MULTIPOLYGON containing square POLYGONs.

Returns

the pointer to newly created Geometry object: NULL on failure.
this function will always return a MultiPolygon
NULL will be returned if any argument is invalid.

See also

gaiaSquareGrid_r, gaiaFreeGeomColl, gaiaTriangularGrid, gaiaHexagonalGrid

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaSquareGrid()
not reentrant and thread unsafe.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaSquareGrid_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom,
		double	origin_x,
		double	origin_y,
		double	size,
		int	only_edges
	)

Utility function: SquareGrid.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	the Geometry to be covered by the Grid.
origin_x	the X ccordinate identifying the Grid Origin.
origin_y	the Y coordinate identifiying the Grid Origin.
size	the Grid cell-side size.
only_edges	if non-zero will return a MULTILINESTRING, otherwise it will return a MULTIPOLYGON containing square POLYGONs.

Returns

the pointer to newly created Geometry object: NULL on failure.
this function will always return a MultiPolygon
NULL will be returned if any argument is invalid.

See also

gaiaSquareGrid, gaiaFreeGeomColl, gaiaTriangularGrid, gaiaHexagonalGrid

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaSquareGrid_r()
reentrant and thread-safe.

GAIAGEO_DECLARE void* gaiaToGeos

(

const gaiaGeomCollPtr

gaia

)

Converts a Geometry object into a GEOS Geometry.

Parameters

gaia	pointer to Geometry object

Returns

handle to GEOS Geometry

See also

gaiaToGeos_r, gaiaFromGeos_XY, gaiaFromGeos_XYZ, gaiaFromGeos_XYM, gaiaFromGeos_XYZM, gaiaToGeosSelective

Note

convenience method, simply defaulting to gaiaToGeosSelective(geom, GAIA2GEOS_ALL)
not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE void* gaiaToGeos_r	(	const void *	p_cache,
		const gaiaGeomCollPtr	gaia
	)

Converts a Geometry object into a GEOS Geometry.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
gaia	pointer to Geometry object

Returns

handle to GEOS Geometry

See also

gaiaToGeos, gaiaFromGeos_XY, gaiaFromGeos_XYZ, gaiaFromGeos_XYM, gaiaFromGeos_XYZM, gaiaToGeosSelective_r

Note

convenience method, simply defaulting to gaiaToGeosSelective_r(p_cache, geom, GAIA2GEOS_ALL)
reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE void* gaiaToGeosSelective	(	const gaiaGeomCollPtr	gaia,
		int	mode
	)

Converts a Geometry object into a GEOS Geometry.

Parameters

gaia	pointer to Geometry object
mode	one of GAIA2GEOS_ALL, GAIA2GEOS_ONLY_POINTS, GAIA2GEOS_ONLY_LINESTRINGS or GAIA2GEOS_ONLY_POLYGONS

Returns

handle to GEOS Geometry

See also

gaiaToGeosSelective_r, gaiaFromGeos_XY, gaiaFromGeos_XYZ, gaiaFromGeos_XYM, gaiaFromGeos_XYZM

Note

if the mode argument is not GAIA2GEOS_ALL only elementary geometries of the selected type will be passed to GEOS, ignoring any other.
not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE void* gaiaToGeosSelective_r	(	const void *	p_cache,
		const gaiaGeomCollPtr	gaia,
		int	mode
	)

Converts a Geometry object into a GEOS Geometry.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
gaia	pointer to Geometry object
mode	one of GAIA2GEOS_ALL, GAIA2GEOS_ONLY_POINTS, GAIA2GEOS_ONLY_LINESTRINGS or GAIA2GEOS_ONLY_POLYGONS

Returns

handle to GEOS Geometry

See also

gaiaToGeosSelective, gaiaFromGeos_XY, gaiaFromGeos_XYZ, gaiaFromGeos_XYM, gaiaFromGeos_XYZM

Note

if the mode argument is not GAIA2GEOS_ALL only elementary geometries of the selected type will be passed to GEOS, ignoring any other.
reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaTriangularGrid	(	gaiaGeomCollPtr	geom,
		double	origin_x,
		double	origin_y,
		double	size,
		int	only_edges
	)

Utility function: TriangularGrid.

Parameters

geom	the Geometry to be covered by the Grid.
origin_x	the X ccordinate identifying the Grid Origin.
origin_y	the Y coordinate identifiying the Grid Origin.
size	the Grid cell-side size.
only_edges	if non-zero will return a MULTILINESTRING, otherwise it will return a MULTIPOLYGON containing triangular POLYGONs.

Returns

the pointer to newly created Geometry object: NULL on failure.
this function will always return a MultiPolygon
NULL will be returned if any argument is invalid.

See also

gaiaTriangularGrid_r, gaiaFreeGeomColl, gaiaSquareGrid, gaiaHexagonalGrid

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaTriangularGrid()
not reentrant and thread unsafe.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaTriangularGrid_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom,
		double	origin_x,
		double	origin_y,
		double	size,
		int	only_edges
	)

Utility function: TriangularGrid.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	the Geometry to be covered by the Grid.
origin_x	the X ccordinate identifying the Grid Origin.
origin_y	the Y coordinate identifiying the Grid Origin.
size	the Grid cell-side size.
only_edges	if non-zero will return a MULTILINESTRING, otherwise it will return a MULTIPOLYGON containing triangular POLYGONs.

Returns

the pointer to newly created Geometry object: NULL on failure.
this function will always return a MultiPolygon
NULL will be returned if any argument is invalid.

See also

gaiaTriangularGrid, gaiaFreeGeomColl, gaiaSquareGrid, gaiaHexagonalGrid

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaTriangularGrid_r()
reentrant and thread-safe.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaUnaryUnion

(

gaiaGeomCollPtr

geom

)

Spatial operator: Unary Union.

Parameters

geom	the input Geometry object.

Returns

the pointer to newly created Geometry object: NULL on failure.
this function is the same as gaiaGeometryUnion, except in that this works internally to the input Geometry itself. NULL on failure.

See also

gaiaUnaryUnion_r, gaiaFreeGeomColl, gaiaGeometryUnion, gaiaUnionCascaded

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaUnaryUnion()
not reentrant and thread unsafe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaUnaryUnion_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom
	)

Spatial operator: Unary Union.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	the input Geometry object.

Returns

the pointer to newly created Geometry object: NULL on failure.
this function is the same as gaiaGeometryUnion, except in that this works internally to the input Geometry itself. NULL on failure.

See also

gaiaUnaryUnion, gaiaFreeGeomColl, gaiaGeometryUnion, gaiaUnionCascaded

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaUnaryUnion_r()
reentrant and thread-safe.

Remarks

GEOS-ADVANCED support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaUnionCascaded

(

gaiaGeomCollPtr

geom

)

Spatial operator: Union Cascaded.

Parameters

geom	the input Geometry object.

Returns

the pointer to newly created Geometry object: NULL on failure.
this function is similar to gaiaUnaryUnion, but it only accepts Polygons and MultiPolygons and it's now deprecated; anyway it's supported on older GEOS versions. NULL on failure.

See also

gaiaUnionCascaded, gaiaFreeGeomColl, gaiaGeometryUnion, gaiaUnionUnion

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaUnionCascaded()
not reentrant and thread unsafe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaUnionCascaded_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom
	)

Spatial operator: Union Cascaded.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	the input Geometry object.

Returns

the pointer to newly created Geometry object: NULL on failure.
this function is similar to gaiaUnaryUnion, but it only accepts Polygons and MultiPolygons and it's now deprecated; anyway it's supported on older GEOS versions. NULL on failure.

See also

gaiaUnionCascaded, gaiaFreeGeomColl, gaiaGeometryUnion, gaiaUnionUnion

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaUnionCascaded_r()
reentrant and thread-safe.

Remarks

GEOS support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaVoronojDiagram	(	gaiaGeomCollPtr	geom,
		double	extra_frame_size,
		double	tolerance,
		int	only_edges
	)

Voronoj Diagram.

Parameters

geom	pointer to input Geometry object.
extra_frame_size	percent factor expanding the BBOX of input Geometry
tolerance	optional snapping tolerance.
only_edges	if non-zero will return a MULTILINESTRING, otherwise it will return a MULTIPOLYGON.

Returns

the pointer to newly created Geometry object: NULL on failure.
NULL will be returned if any argument is invalid.

See also

gaiaVoronojDiagram_r, gaiaFreeGeomColl, gaiaDelaunayTriangulation

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaVoronojDiagram()
not reentrant and thread unsafe.

Remarks

GEOS-TRUNK support required.

GAIAGEO_DECLARE gaiaGeomCollPtr gaiaVoronojDiagram_r	(	const void *	p_cache,
		gaiaGeomCollPtr	geom,
		double	extra_frame_size,
		double	tolerance,
		int	only_edges
	)

Voronoj Diagram.

Parameters

p_cache	a memory pointer returned by spatialite_alloc_connection()
geom	pointer to input Geometry object.
extra_frame_size	percent factor expanding the BBOX of input Geometry
tolerance	optional snapping tolerance.
only_edges	if non-zero will return a MULTILINESTRING, otherwise it will return a MULTIPOLYGON.

Returns

the pointer to newly created Geometry object: NULL on failure.
NULL will be returned if any argument is invalid.

See also

gaiaVoronojDiagram, gaiaFreeGeomColl, gaiaDelaunayTriangulation

Note

you are responsible to destroy (before or after) any allocated Geometry, this including any Geometry returned by gaiaVoronojDiagram_r()
reentrant and thread-safe.

Remarks

GEOS-TRUNK support required.