Smooth geometries using the Chaikin algorithm

Applies Chaikin's corner-cutting algorithm for the given number of iterations to produce smoother curves. Accepts linestrings, multilinestrings, polygons, and multipolygons.

Usage

ga_chaikin_smoothing(geometry, n_iterations)

Arguments

geometry

a GeoArrow linestring, multilinestring, polygon, or multipolygon array

n_iterations

the number of smoothing iterations to apply; must be greater than 0

Value

a GeoArrow array of the same geometry type as the input

References

ChaikinSmoothing

See also

Other misc: ga_buffer(), ga_centroid(), ga_line_segmentize(), ga_remove_repeated_points()

Examples

zigzag <- geoarrow::as_geoarrow_array(sf::st_sfc(
  sf::st_linestring(rbind(c(0, 0), c(1, 2), c(2, 0), c(3, 2)))
))

# each iteration cuts every corner, so the vertex count grows
as.vector(ga_n_coords(zigzag))
#> [1] 4
as.vector(ga_n_coords(ga_chaikin_smoothing(zigzag, 2)))
#> [1] 16

geoarrow::as_geoarrow_vctr(ga_chaikin_smoothing(zigzag, 1))
#> <geoarrow_vctr geoarrow.linestring{list}[1]>
#> [1] <LINESTRING (0 0, 0.25 0.5, 0.75 1.5, 1.25 1.5, 1.75 0.5, 2.25 0.5, 2.7>