Label Layer

Put labels on a map.

labelLayer(
  x,
  spdf,
  df,
  spdfid = NULL,
  dfid = NULL,
  txt,
  col = "black",
  cex = 0.7,
  overlap = TRUE,
  show.lines = TRUE,
  halo = FALSE,
  bg = "white",
  r = 0.1,
  ...
)

Arguments

x: an sf object, a simple feature collection. spdf, df, dfid and spdfid are not used.
spdf: a SpatialPointsDataFrame or a SpatialPolygonsDataFrame; if spdf is a SpatialPolygonsDataFrame texts are plotted on centroids.
df: a data frame that contains the labels to plot. If df is missing spdf@data is used instead.
spdfid: name of the identifier variable in spdf, default to the first column of the spdf data frame. (optional)
dfid: name of the identifier variable in df, default to the first column of df. (optional)
txt: labels variable.
col: labels color.
cex: labels cex.
overlap: if FALSE, labels are moved so they do not overlap.
show.lines: if TRUE, then lines are plotted between x,y and the word, for those words not covering their x,y coordinate
halo: If TRUE, then a 'halo' is printed around the text and additional arguments bg and r can be modified to set the color and width of the halo.
bg: halo color if halo is TRUE
r: width of the halo
...: further text arguments.

Examples

library(sf)
opar <- par(mar = c(0,0,0,0))
mtq <- st_read(system.file("gpkg/mtq.gpkg", package="cartography"))
#> Reading layer `mtq' from data source 
#>   `/tmp/RtmpmpfIrO/temp_libpath18ee15f22a9e/cartography/gpkg/mtq.gpkg' 
#>   using driver `GPKG'
#> Simple feature collection with 34 features and 7 fields
#> Geometry type: MULTIPOLYGON
#> Dimension:     XY
#> Bounding box:  xmin: 690574 ymin: 1592536 xmax: 735940.2 ymax: 1645660
#> Projected CRS: WGS 84 / UTM zone 20N
plot(st_geometry(mtq), col = "darkseagreen3", border = "darkseagreen4", 
     bg = "#A6CAE0")
labelLayer(x = mtq, txt = "LIBGEO", col= "black", cex = 0.7, font = 4,
           halo = TRUE, bg = "white", r = 0.1, 
           overlap = FALSE, show.lines = FALSE)

par(opar)

Arguments

See also

Examples