Compute a representative point inside a geometry

Returns a point guaranteed to lie on the geometry, unlike ga_centroid(), which can fall outside a concave shape.

Usage

ga_interior_point(geometry)

Arguments

geometry

a GeoArrow geometry array

Value

a GeoArrow point array of the same length as geometry

Details

For a polygon this is a point on the interior, chosen from the horizontal line closest to the centroid. An empty or null geometry becomes a null element.

References

InteriorPoint

See also

Other query: ga_closest_point(), ga_is_convex(), ga_line_locate_point()

Examples

g <- geoarrow::as_geoarrow_array(sf::st_sfc(sf::st_polygon(list(
  matrix(c(0, 0, 4, 0, 4, 4, 0, 4, 0, 0), ncol = 2, byrow = TRUE)
))))

sf::st_as_sfc(geoarrow::as_geoarrow_vctr(ga_interior_point(g)))
#> Geometry set for 1 feature 
#> Geometry type: POINT
#> Dimension:     XY
#> Bounding box:  xmin: 2 ymin: 2 xmax: 2 ymax: 2
#> CRS:           NA
#> POINT (2 2)