rasterize simple feature geometries

rasterize simple feature geometries

st_rasterize(
  sf,
  template = guess_raster(sf, ...) %||% st_as_stars(st_bbox(sf), values = NA_real_,
    ...),
  file = tempfile(),
  driver = "GTiff",
  options = character(0),
  ...
)

Arguments

sf	object of class sf
template	stars object with desired target geometry
file	temporary file name
driver	driver for temporary file
options	character; options vector for GDALRasterize
...	arguments passed on to st_as_stars

Examples

demo(nc, echo = FALSE, ask = FALSE)
#> Reading layer `nc.gpkg' from data source `/home/runner/work/_temp/Library/sf/gpkg/nc.gpkg' using driver `GPKG'
#> Simple feature collection with 100 features and 14 fields
#> Attribute-geometry relationship: 0 constant, 8 aggregate, 6 identity
#> geometry type:  MULTIPOLYGON
#> dimension:      XY
#> bbox:           xmin: -84.32385 ymin: 33.88199 xmax: -75.45698 ymax: 36.58965
#> geographic CRS: NAD27
(x = st_rasterize(nc)) # default grid:
#> stars object with 2 dimensions and 1 attribute
#> attribute(s):
#>      AREA       
#>  Min.   :0.042  
#>  1st Qu.:0.108  
#>  Median :0.142  
#>  Mean   :0.145  
#>  3rd Qu.:0.181  
#>  Max.   :0.241  
#>  NA's   :30904  
#> dimension(s):
#>   from  to   offset      delta refsys point values x/y
#> x    1 461 -84.3239  0.0192484  NAD27 FALSE   NULL [x]
#> y    1 141  36.5896 -0.0192484  NAD27 FALSE   NULL [y]
plot(x, axes = TRUE)
# a bit more customized grid:
(x = st_rasterize(nc, st_as_stars(st_bbox(nc), nx = 100, ny = 50, values = NA_real_)))
#> stars object with 2 dimensions and 1 attribute
#> attribute(s):
#>      AREA        
#>  Min.   :0.0420  
#>  1st Qu.:0.1080  
#>  Median :0.1420  
#>  Mean   :0.1455  
#>  3rd Qu.:0.1810  
#>  Max.   :0.2410  
#>  NA's   :2373    
#> dimension(s):
#>   from  to   offset      delta refsys point values x/y
#> x    1 100 -84.3239  0.0886687  NAD27 FALSE   NULL [x]
#> y    1  50  36.5896 -0.0541531  NAD27 FALSE   NULL [y]
plot(x, axes = TRUE)
(ls = st_sf(a = 1:2, st_sfc(st_linestring(rbind(c(0.1, 0), c(1.1, 1))),
   st_linestring(rbind(c(0, 0.05), c(1, 0.05))))))
#> Simple feature collection with 2 features and 1 field
#> geometry type:  LINESTRING
#> dimension:      XY
#> bbox:           xmin: 0 ymin: 0 xmax: 1.1 ymax: 1
#> CRS:            NA
#>   a
#> 1 1
#> 2 2
#>   c..st_sfc.st_linestring.rbind.c.0.1..0...c.1.1..1.....st_linestring.rbind.c.0..........0.05...c.1..0.05......
#> 1                                                                                     LINESTRING (0.1 0, 1.1 1)
#> 2                                                                                   LINESTRING (0 0.05, 1 0.05)
(grd = st_as_stars(st_bbox(ls), nx = 10, ny = 10, xlim = c(0, 1.0), ylim = c(0, 1),
   values = NA_real_))
#> stars object with 2 dimensions and 1 attribute
#> attribute(s):
#>     values    
#>  Min.   : NA  
#>  1st Qu.: NA  
#>  Median : NA  
#>  Mean   :NaN  
#>  3rd Qu.: NA  
#>  Max.   : NA  
#>  NA's   :100  
#> dimension(s):
#>   from to offset delta refsys point values x/y
#> x    1 10      0   0.1     NA    NA   NULL [x]
#> y    1 10      1  -0.1     NA    NA   NULL [y]
# Only the left-top corner is part of the grid cell:
sf_extSoftVersion()["GDAL"]
#>    GDAL 
#> "3.0.4" 
plot(st_rasterize(ls, grd), axes = TRUE, reset = FALSE) # ALL_TOUCHED=FALSE; 
plot(ls, add = TRUE, col = "red")
plot(st_rasterize(ls, grd, options = "ALL_TOUCHED=TRUE"), axes = TRUE, reset = FALSE)
plot(ls, add = TRUE, col = "red")
# add lines to existing 0 values, summing values in case of multiple lines:
(grd = st_as_stars(st_bbox(ls), nx = 10, ny = 10, xlim = c(0, 1.0), ylim = c(0, 1), values = 0))
#> stars object with 2 dimensions and 1 attribute
#> attribute(s):
#>     values  
#>  Min.   :0  
#>  1st Qu.:0  
#>  Median :0  
#>  Mean   :0  
#>  3rd Qu.:0  
#>  Max.   :0  
#> dimension(s):
#>   from to offset delta refsys point values x/y
#> x    1 10      0   0.1     NA    NA   NULL [x]
#> y    1 10      1  -0.1     NA    NA   NULL [y]
r = st_rasterize(ls, grd, options = c("MERGE_ALG=ADD", "ALL_TOUCHED=TRUE"))
plot(r, axes = TRUE, reset = FALSE)
plot(ls, add = TRUE, col = "red")