down-cast structures

[SymbolixAU]

Similar to expand_geometries, have a simplify_multi argument to simplify geometries?

TODO

• [ ] MULTIPOINT to POINT
• [ ] MULTILINESTRING to LINESTRING
• [ ] MULTIPOLYGON to POLYGON

[SymbolixAU]

nc <- sf::st_read(system.file("shape/nc.shp", package="sf"))

library(microbenchmark)

microbenchmark(
    sf = {
        nc_poly <- sf::st_cast( nc, to = "POLYGON")
        geo_poly <- geojsonsf::sf_geojson( nc_poly )
    },
    geojsonsf = {
        geo_sf <- geojsonsf:::rcpp_sf_to_geojson_downcast( nc )
    },
    times = 5
)

# Unit: milliseconds
#      expr       min        lq      mean    median        uq       max neval
#        sf 16.019968 16.952798 20.264359 17.283295 19.396397 31.669338     5
# geojsonsf  2.348934  2.597222  3.203101  2.847933  3.017071  5.204344     5

even using geojsonsf to to down-cast to GeoJOSN, then back to sf is performant.

microbenchmark(
    sf = {
        nc_poly <- sf::st_cast( nc, to = "POLYGON")
        geo_poly <- geojsonsf::sf_geojson( nc_poly )
    },
    geojsonsf = {
        geo_sf <- geojsonsf:::rcpp_sf_to_geojson_downcast( nc )
        nc2 <- geojsonsf::geojson_sf( geo_sf )
    },
    times = 5
)

# Unit: milliseconds
#      expr      min       lq     mean   median       uq      max neval
#        sf 13.75293 14.42003 16.96273 14.93394 15.38814 26.31861     5
# geojsonsf 10.78687 11.34112 11.60321 11.63283 11.75583 12.49937     5

[SymbolixAU]

Moving this into mapdeck & spatialwidget