geos.GEOSPolygonHullSimplify ⇒ GEOSGeometry
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Computes a boundary-respecting hull of a polygonal geometry, with hull shape determined by a target parameter specifying the fraction of the input vertices retained in the result. Larger values produce less concave results. A value of 1 produces the convex hull; a value of 0 produces the original geometry. An outer hull is computed if the parameter is positive, an inner hull is computed if it is negative.
Kind: global property of geos
Returns: GEOSGeometry
- A newly allocated geometry of the concave hull. NULL on exception.
Param | Type | Description |
---|---|---|
g | GEOSGeometry | the polygonal geometry to process |
isOuter | number | indicates whether to compute an outer or inner hull (1 for outer hull, 0 for inner) |
vertexNumFraction | number | the target fraction of the count of input vertices to retain in result |
geos.GEOSPolygonHullSimplifyMode ⇒ GEOSGeometry
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Computes a topology-preserving simplified hull of a polygonal geometry, with hull shape determined by the parameter, controlled by a parameter mode, which is one defined in GEOSPolygonHullParameterModes. Larger values compute less concave results and a value of 0 produces the original geometry. Either outer or inner hulls can be computed.
Kind: global property of geos
Returns: GEOSGeometry
- A newly allocated geometry of the concave hull. NULL on exception.
Param | Type | Description |
---|---|---|
g | GEOSGeometry | the polygonal geometry to process |
isOuter | number | indicates whether to compute an outer or inner hull (1 for outer hull, 0 for inner) |
parameterMode | number | the interpretation to apply to the parameter argument; see GEOSPolygonHullParameterModes |
parameter | number | the target ratio of area difference to original area |
geos.GEOSPolygonHullSimplifyMode_r ⇒ GEOSGeometry
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Computes a topology-preserving simplified hull of a polygonal geometry, with hull shape determined by the parameter, controlled by a parameter mode, which is one defined in GEOSPolygonHullParameterModes. Larger values compute less concave results and a value of 0 produces the original geometry. Either outer or inner hulls can be computed.
Kind: global property of geos
Returns: GEOSGeometry
- A newly allocated geometry of the concave hull. NULL on exception.
Param | Type | Description |
---|---|---|
handle | GEOSContextHandle_t | - |
g | GEOSGeometry | the polygonal geometry to process |
isOuter | number | indicates whether to compute an outer or inner hull (1 for outer hull, 0 for inner) |
parameterMode | number | the interpretation to apply to the parameter argument; see GEOSPolygonHullParameterModes |
parameter | number | the target ratio of area difference to original area |
geos.GEOSPolygonHullSimplify_r ⇒ GEOSGeometry
⏏
Computes a boundary-respecting hull of a polygonal geometry, with hull shape determined by a target parameter specifying the fraction of the input vertices retained in the result. Larger values produce less concave results. A value of 1 produces the convex hull; a value of 0 produces the original geometry. An outer hull is computed if the parameter is positive, an inner hull is computed if it is negative.
Kind: global property of geos
Returns: GEOSGeometry
- A newly allocated geometry of the concave hull. NULL on exception.
Param | Type | Description |
---|---|---|
handle | GEOSContextHandle_t | - |
g | GEOSGeometry | the polygonal geometry to process |
isOuter | number | indicates whether to compute an outer or inner hull (1 for outer hull, 0 for inner) |
vertexNumFraction | number | the target fraction of the count of input vertices to retain in result |