Quasi-geographic buffering

Generate the buffer of spatial object in geographic coordinates. The function transforms the object into Azimuthal equidistant projection, then buffers it by the specified radius and then reprojects into geographical coordinate system (WGS84)

Usage

gr_buffer_geo(g, bufsize)

Arguments

g

sf or sfg object with known coordinate system.

bufsize

Numeric value of a buffer distance, in meters.

Value

sf or sfg object, buffered to bufsize and projected into geographic coordinates (WGS84).

Examples

if (require("sf")) {

  library(grwat)
  library(ggplot2)
  path = system.file("extdata", "spas-zagorye.gpkg", package = "grwat")
  basin = sf::st_read(path, layer = 'basin') # read basin region

  basin_buffer = gr_buffer_geo(basin, 25000)

  ggplot() +
    geom_sf(data = basin_buffer, fill = 'orangered', color = 'black') +
    geom_sf(data = basin, fill = 'steelblue', color = 'black')

}
#> Loading required package: sf
#> Linking to GEOS 3.10.2, GDAL 3.4.1, PROJ 8.2.1; sf_use_s2() is TRUE
#> Reading layer `basin' from data source 
#>   `/home/runner/work/_temp/Library/grwat/extdata/spas-zagorye.gpkg' 
#>   using driver `GPKG'
#> Simple feature collection with 1 feature and 7 fields
#> Geometry type: MULTIPOLYGON
#> Dimension:     XY
#> Bounding box:  xmin: 35.41204 ymin: 54.88195 xmax: 36.84138 ymax: 55.57005
#> Geodetic CRS:  WGS 84