Fortify SpatRasters and SpatVectors to data frames for compatibility with
ggplot2::ggplot().
Arguments
- model
A SpatRaster created with
terra::rast()or a SpatVector created withterra::vect().- data
Not used by this method.
- ...
other arguments passed to methods
- .name_repair
Treatment of problematic column names:
"minimal": No name repair or checks, beyond basic existence,"unique": Make sure names are unique and not empty,"check_unique": (default value), no name repair, but check they areunique,"universal": Make the namesuniqueand syntactica function: apply custom name repair (e.g.,
.name_repair = make.namesfor names in the style of base R).A purrr-style anonymous function, see
rlang::as_function()
- maxcell
positive integer. Maximum number of cells to use for the plot.
Value
fortify.SpatVector() returns a sf object and
fortify.SpatRaster() returns a tibble. See Methods.
Methods
Implementation of the generic ggplot2::fortify() function.
SpatRaster
Return a tibble than can be used with ggplot2::geom_* like
ggplot2::geom_point(), ggplot2::geom_raster(), etc.
The resulting tibble includes the coordinates on the columns x,y. The
values of each layer are included as additional columns named as per the
name of the layer on the SpatRaster.
The CRS of the SpatRaster can be retrieved with
attr(<fortifiedSpatRaster>, "crs").
It is possible to convert the fortified object onto a SpatRaster again with
as_spatraster().
SpatVector
Return a sf object than can be used with ggplot2::geom_sf().
See also
sf::st_as_sf(), as_tibble.Spat, as_spatraster(),
ggplot2::fortify().
Other ggplot2 utils:
autoplot.Spat,
geom_spat_contour,
geom_spatraster_rgb(),
geom_spatraster(),
ggspatvector,
stat_spat_coordinates()
Other ggplot2 methods:
autoplot.Spat
Coercing objects:
as_coordinates(),
as_sf(),
as_spatraster(),
as_spatvector(),
as_tibble.Spat
Examples
# \donttest{
# Get a SpatRaster
r <- system.file("extdata/volcano2.tif", package = "tidyterra") %>%
terra::rast()
fortified <- ggplot2::fortify(r)
fortified
#> # A tibble: 21,228 × 3
#> x y elevation
#> <dbl> <dbl> <dbl>
#> 1 1756972. 5917870. 80.6
#> 2 1756976. 5917870. 80.4
#> 3 1756982. 5917870. 80.5
#> 4 1756986. 5917870. 80.6
#> 5 1756992. 5917870. 81.2
#> 6 1756996. 5917870. 81.5
#> 7 1757002. 5917870. 81.3
#> 8 1757006. 5917870. 80.9
#> 9 1757012. 5917870. 79.8
#> 10 1757016. 5917870. 77.8
#> # … with 21,218 more rows
# The crs is an attribute of the fortified SpatRaster
attr(fortified, "crs")
#> [1] "PROJCRS[\"NZGD2000 / New Zealand Transverse Mercator 2000\",\n BASEGEOGCRS[\"NZGD2000\",\n DATUM[\"New Zealand Geodetic Datum 2000\",\n ELLIPSOID[\"GRS 1980\",6378137,298.257222101,\n LENGTHUNIT[\"metre\",1]]],\n PRIMEM[\"Greenwich\",0,\n ANGLEUNIT[\"degree\",0.0174532925199433]],\n ID[\"EPSG\",4167]],\n CONVERSION[\"New Zealand Transverse Mercator 2000\",\n METHOD[\"Transverse Mercator\",\n ID[\"EPSG\",9807]],\n PARAMETER[\"Latitude of natural origin\",0,\n ANGLEUNIT[\"degree\",0.0174532925199433],\n ID[\"EPSG\",8801]],\n PARAMETER[\"Longitude of natural origin\",173,\n ANGLEUNIT[\"degree\",0.0174532925199433],\n ID[\"EPSG\",8802]],\n PARAMETER[\"Scale factor at natural origin\",0.9996,\n SCALEUNIT[\"unity\",1],\n ID[\"EPSG\",8805]],\n PARAMETER[\"False easting\",1600000,\n LENGTHUNIT[\"metre\",1],\n ID[\"EPSG\",8806]],\n PARAMETER[\"False northing\",10000000,\n LENGTHUNIT[\"metre\",1],\n ID[\"EPSG\",8807]]],\n CS[Cartesian,2],\n AXIS[\"northing (N)\",north,\n ORDER[1],\n LENGTHUNIT[\"metre\",1]],\n AXIS[\"easting (E)\",east,\n ORDER[2],\n LENGTHUNIT[\"metre\",1]],\n USAGE[\n SCOPE[\"Engineering survey, topographic mapping.\"],\n AREA[\"New Zealand - North Island, South Island, Stewart Island - onshore.\"],\n BBOX[-47.33,166.37,-34.1,178.63]],\n ID[\"EPSG\",2193]]"
# Back to a SpatRaster with
as_spatraster(fortified)
#> class : SpatRaster
#> dimensions : 174, 122, 1 (nrow, ncol, nlyr)
#> resolution : 5, 5 (x, y)
#> extent : 1756969, 1757579, 5917003, 5917873 (xmin, xmax, ymin, ymax)
#> coord. ref. : NZGD2000 / New Zealand Transverse Mercator 2000 (EPSG:2193)
#> source(s) : memory
#> name : elevation
#> min value : 76.26222
#> max value : 195.55420
# You can now use a SpatRaster with raster, contours, etc.
library(ggplot2)
# Use here the raster with resample
ggplot(r, maxcell = 10000) +
# Need the aes parameters
geom_raster(aes(x, y, fill = elevation)) +
# Adjust the coords
coord_equal()
#> SpatRaster resampled to ncells = 10080
# Or any other geom
ggplot(r) +
geom_histogram(aes(x = elevation),
bins = 20, fill = "lightblue",
color = "black"
)
# Create a SpatVector
extfile <- system.file("extdata/cyl.gpkg", package = "tidyterra")
cyl <- terra::vect(extfile)
cyl
#> class : SpatVector
#> geometry : polygons
#> dimensions : 9, 3 (geometries, attributes)
#> extent : 2892687, 3341372, 2017622, 2361600 (xmin, xmax, ymin, ymax)
#> source : cyl.gpkg
#> coord. ref. : ETRS89-extended / LAEA Europe (EPSG:3035)
#> names : iso2 cpro name
#> type : <chr> <chr> <chr>
#> values : ES-AV 05 Avila
#> ES-BU 09 Burgos
#> ES-LE 24 Leon
# To sf
ggplot2::fortify(cyl)
#> Simple feature collection with 9 features and 3 fields
#> Geometry type: GEOMETRY
#> Dimension: XY
#> Bounding box: xmin: 2892687 ymin: 2017622 xmax: 3341372 ymax: 2361600
#> Projected CRS: ETRS89-extended / LAEA Europe
#> iso2 cpro name geometry
#> 1 ES-AV 05 Avila POLYGON ((3126360 2066778, ...
#> 2 ES-BU 09 Burgos MULTIPOLYGON (((3276731 226...
#> 3 ES-LE 24 Leon POLYGON ((3049427 2233673, ...
#> 4 ES-P 34 Palencia MULTIPOLYGON (((3175411 229...
#> 5 ES-SA 37 Salamanca POLYGON ((3042661 2138939, ...
#> 6 ES-SG 40 Segovia POLYGON ((3126360 2066778, ...
#> 7 ES-SO 42 Soria POLYGON ((3194084 2154251, ...
#> 8 ES-VA 47 Valladolid MULTIPOLYGON (((3158120 216...
#> 9 ES-ZA 49 Zamora POLYGON ((3042661 2138939, ...
# Now you can use geom_sf()
library(ggplot2)
ggplot(cyl) +
geom_sf()
# }