Voronoi edges from geometry vertices

Returns one multilinestring per input geometry, whose parts are the boundaries between that geometry's Voronoi cells. The output has the same length as the input.

Usage

ga_voronoi_edges(geometry, clip = "padded", tolerance = 0, boundary = NULL)

Arguments

geometry

a GeoArrow geometry array whose vertices are the sites

clip

how to bound the diagram, either "padded" or "envelope". Ignored when boundary is supplied

tolerance

sites closer together than this are snapped to the same position; length 1 or the same length as geometry

boundary

an optional GeoArrow polygon array to clip to; length 1 or the same length as geometry

Value

a GeoArrow multilinestring array of the same length as geometry

Details

Unlike ga_voronoi_cells(), this works on collinear sites, where the edges are the perpendicular bisectors between neighbouring points. Prefer it when you want the diagram's skeleton rather than closed regions.

A geometry with fewer than two distinct vertices has no edges and comes back as an empty multilinestring. A null geometry stays null.

References

Voronoi

See also

Other voronoi: ga_voronoi_cells()

Examples

pts <- sf::st_multipoint(cbind(c(0, 1, 1, 0), c(0, 0, 1, 1)))
g <- geoarrow::as_geoarrow_array(sf::st_sfc(pts))

sf::st_as_sfc(geoarrow::as_geoarrow_vctr(ga_voronoi_edges(g)))
#> Geometry set for 1 feature 
#> Geometry type: MULTILINESTRING
#> Dimension:     XY
#> Bounding box:  xmin: -0.5 ymin: -0.5 xmax: 1.5 ymax: 1.5
#> CRS:           NA
#> MULTILINESTRING ((0.5 0.5, 0.5 -0.5), (0.5 0.5,...