Create a Virtual Raster (VRT) file from .tif files
create_VRT_from_dir(
dir_tifs,
output_path_VRT,
file_extension = ".tif",
verbose = FALSE
)a valid path to a directory where the .tif files are saved
a valid path to a file where the Virtual Raster (VRT) will be saved
a character string specifying the image file extension from which the .vrt file will be built
a boolean. If TRUE then information will be printed out in the console
it doesn't return an object but it saves the output to a file
if (FALSE) { # \dontrun{
#.........................................................
# create a directory to save the .tif files and a
# Well Known Text (WKT) of a sample Area of Interest (AOI)
#.........................................................
DIR_SAVE = file.path(Sys.getenv('HOME'), 'DIR_SAVE_DEM')
if (!dir.exists(DIR_SAVE)) dir.create(DIR_SAVE)
WKT='POLYGON((61.5234 27.0591, 63.6328 27.0591, 63.6328 28.1495, 61.5234 28.1495, 61.5234 27.0591))'
sf_obj = sf::st_as_sfc(WKT, crs = 4326)
sf_obj = sf::st_make_valid(sf_obj)
#......................
# download 90 meter DEM
#......................
save_matches = CopernicusDEM::aoi_geom_save_tif_matches(sf_or_file = sf_obj,
dir_save_tifs = DIR_SAVE,
resolution = 90,
crs_value = 4326,
threads = parallel::detectCores(),
verbose = TRUE)
#........................................
# create a Virtual Raster (VRT) file from
# the 90 meter downloaded .tif files
#........................................
VRT_out = as.character(glue::glue("{DIR_SAVE}.vrt"))
res_vrt = CopernicusDEM::create_VRT_from_dir(dir_tifs = DIR_SAVE,
output_path_VRT = VRT_out,
verbose = TRUE)
#......................................................
# load the saved VRT file as raster (which might
# consist of multiple files, i.e. a mosaic) and plot it
#......................................................
rst = raster::raster(VRT_out)
sp::plot(rst)
} # }