生成面要素的中心点-GDAL

PointOnSurface(Geometry self) -> Geometry

OGRGeometryH
OGR_G_PointOnSurface(OGRGeometryH hGeom)

Returns a point guaranteed to lie on the surface.

This method relates to the SFCOM ISurface::get_PointOnSurface() method
however the current implementation based on GEOS can operate on other
geometry types than the types that are supported by SQL/MM-Part 3 :
surfaces (polygons) and multisurfaces (multipolygons).

This method is built on the GEOS library, check it for the definition
of the geometry operation. If OGR is built without the GEOS library,
this method will always fail, issuing a CPLE_NotSupported error.

Parameters:
-----------

hGeom:  the geometry to operate on.

a point guaranteed to lie on the surface or NULL if an error occurred.

OGR 1.10

Centroid(Geometry self) -> Geometry

int OGR_G_Centroid(OGRGeometryH hGeom, OGRGeometryH  hCentroidPoint)

Compute the geometry centroid.

The centroid location is applied to the passed in OGRPoint object. The  centroid is not necessarily within the geometry.

This method relates to the SFCOM ISurface::get_Centroid() method  however the current implementation based on GEOS can operate on other  geometry types such as multipoint, linestring, geometrycollection such as  multipolygons. OGC SF SQL 1.1 defines the operation for surfaces  (polygons). SQL/MM-Part 3 defines the operation for surfaces and  multisurfaces (multipolygons).

This function is the same as the C++ method  OGRGeometry::Centroid().

This function is built on the GEOS library, check it for the  definition of the geometry operation. If OGR is built without the GEOS  library, this function will always fail, issuing a CPLE_NotSupported  error.

OGRERR_NONE on success or OGRERR_FAILURE on error.

import ogr

p = ogr.CreateGeometryFromWkt('POLYGON((1 1,5 1,5 5,1 5,1 1),(2 2,2 4,4 4,4 2,2 2)) ')

#生成内部点

#方式一

p.PointOnSurface().ExportToWkt()

#方式二

p.Centroid().ExportToWkt()