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Compute buffer of a WKB/WKT geometry

Source: R/geom.R
g_buffer.Rd

g_buffer() builds a new geometry containing the buffer region around the geometry on which it is invoked. The buffer is a polygon containing the region within the buffer distance of the original geometry. Wrapper of OGR_G_Buffer()in the GDL API (GEOS via GDAL headers).

Usage

g_buffer(
  geom,
  dist,
  quad_segs = 30L,
  as_wkb = TRUE,
  as_iso = FALSE,
  byte_order = "LSB",
  quiet = FALSE
)

Arguments

geom

Either a raw vector of WKB or list of raw vectors, or a character vector containing one or more WKT strings.

dist

Numeric buffer distance in units of the input geom.

quad_segs

Integer number of segments used to define a 90 degree curve (quadrant of a circle). Large values result in large numbers of vertices in the resulting buffer geometry while small numbers reduce the accuracy of the result.

as_wkb

Logical value, TRUE to return the output geometry in WKB format (the default), or FALSE to return as WKT.

as_iso

Logical value, TRUE to export as ISO WKB/WKT (ISO 13249 SQL/MM Part 3), or FALSE (the default) to export as "Extended WKB/WKT".

byte_order

Character string specifying the byte order when output is WKB. One of "LSB" (the default) or "MSB" (uncommon).

quiet

Logical value, TRUE to suppress warnings. Defaults to FALSE.

Value

A polygon as WKB raw vector or WKT string, or a list/character vector of polygons as WKB/WKT with length equal to the number of input geometries. NA is returned with a warning if WKB input cannot be converted into an OGR geometry object, or if an error occurs in the call to the underlying OGR API.

Examples

g_buffer("POINT (0 0)", dist = 10, as_wkb = FALSE)
#> [1] "POLYGON ((10 0,9.98629534754574 -0.523359562429438,9.94521895368273 -1.04528463267653,9.87688340595138 -1.56434465040231,9.78147600733806 -2.07911690817759,9.65925826289068 -2.58819045102521,9.51056516295153 -3.09016994374947,9.33580426497202 -3.583679495453,9.13545457642601 -4.067366430758,8.91006524188368 -4.53990499739547,8.66025403784439 -5,8.38670567945424 -5.44639035015027,8.09016994374947 -5.87785252292473,7.77145961456971 -6.29320391049837,7.43144825477394 -6.69130606358858,7.07106781186548 -7.07106781186547,6.69130606358858 -7.43144825477394,6.29320391049838 -7.77145961456971,5.87785252292473 -8.09016994374947,5.44639035015027 -8.38670567945424,5.0 -8.66025403784439,4.53990499739547 -8.91006524188368,4.067366430758 -9.13545457642601,3.583679495453 -9.33580426497202,3.09016994374947 -9.51056516295153,2.58819045102521 -9.65925826289068,2.07911690817759 -9.78147600733806,1.56434465040231 -9.87688340595138,1.04528463267654 -9.94521895368273,0.52335956242944 -9.98629534754574,0.0 -10,-0.523359562429436 -9.98629534754574,-1.04528463267653 -9.94521895368273,-1.56434465040231 -9.87688340595138,-2.07911690817759 -9.78147600733806,-2.58819045102521 -9.65925826289068,-3.09016994374947 -9.51056516295154,-3.583679495453 -9.33580426497202,-4.067366430758 -9.13545457642601,-4.53990499739547 -8.91006524188368,-5 -8.66025403784439,-5.44639035015027 -8.38670567945424,-5.87785252292473 -8.09016994374947,-6.29320391049837 -7.77145961456971,-6.69130606358858 -7.43144825477394,-7.07106781186547 -7.07106781186548,-7.43144825477394 -6.69130606358858,-7.77145961456971 -6.29320391049838,-8.09016994374947 -5.87785252292473,-8.38670567945424 -5.44639035015027,-8.66025403784439 -5,-8.91006524188368 -4.53990499739547,-9.13545457642601 -4.067366430758,-9.33580426497202 -3.58367949545301,-9.51056516295153 -3.09016994374947,-9.65925826289068 -2.58819045102521,-9.78147600733806 -2.0791169081776,-9.87688340595138 -1.56434465040231,-9.94521895368273 -1.04528463267654,-9.98629534754574 -0.523359562429442,-10 -0.0,-9.98629534754574 0.523359562429436,-9.94521895368273 1.04528463267653,-9.87688340595138 1.56434465040231,-9.78147600733806 2.07911690817759,-9.65925826289068 2.5881904510252,-9.51056516295154 3.09016994374947,-9.33580426497202 3.583679495453,-9.13545457642601 4.067366430758,-8.91006524188368 4.53990499739547,-8.66025403784439 5.0,-8.38670567945424 5.44639035015027,-8.09016994374948 5.87785252292473,-7.77145961456971 6.29320391049837,-7.43144825477395 6.69130606358858,-7.07106781186548 7.07106781186547,-6.69130606358858 7.43144825477394,-6.29320391049838 7.77145961456971,-5.87785252292473 8.09016994374947,-5.44639035015028 8.38670567945424,-5 8.66025403784438,-4.53990499739547 8.91006524188368,-4.06736643075801 9.135454576426,-3.58367949545301 9.33580426497202,-3.09016994374948 9.51056516295153,-2.58819045102522 9.65925826289068,-2.0791169081776 9.78147600733806,-1.56434465040231 9.87688340595138,-1.04528463267654 9.94521895368273,-0.523359562429443 9.98629534754574,-0.0 10.0,0.523359562429431 9.98629534754574,1.04528463267653 9.94521895368273,1.56434465040231 9.87688340595138,2.07911690817759 9.78147600733806,2.5881904510252 9.65925826289068,3.09016994374947 9.51056516295154,3.583679495453 9.33580426497202,4.067366430758 9.13545457642601,4.53990499739547 8.91006524188368,4.99999999999999 8.66025403784439,5.44639035015027 8.38670567945424,5.87785252292473 8.09016994374948,6.29320391049837 7.77145961456971,6.69130606358858 7.43144825477395,7.07106781186547 7.07106781186548,7.43144825477394 6.69130606358859,7.77145961456971 6.29320391049838,8.09016994374947 5.87785252292473,8.38670567945424 5.44639035015028,8.66025403784438 5.0,8.91006524188368 4.53990499739547,9.135454576426 4.06736643075801,9.33580426497202 3.58367949545301,9.51056516295153 3.09016994374948,9.65925826289068 2.58819045102522,9.78147600733806 2.0791169081776,9.87688340595138 1.56434465040231,9.94521895368273 1.04528463267654,9.98629534754574 0.523359562429444,10 0))"