R/writeEpmSpatial.R

In epm: EcoPhyloMapper

##'@title Write epmGrid Spatial Object to Disk
##'
##'@description Writes the grid to disk for use in other GIS applications.
##'
##'@param x object of class \code{epmGrid}
##'@param filename filename to be written to, with the appropriate file
##'  extension
##'@param ... additional arguments to be passed to \code{\link[sf]{st_write}} or
##'  \code{\link[terra]{writeRaster}}.
##'
##'@return the object is written to disk, nothing is returned.
##'
##'@details For hexagonal grid systems, appending .shp to the filename will
##'  result in a shapefile, whereas appending .gpkg results in a geopackage
##'  file. See \code{\link[sf]{st_write}} for additional options. For square
##'  grid cells, appending .tif will result in a GeoTiff file being written to
##'  disk. If no extensions are included with the filename, then this function
##'  will default to geopackage files for hexagonal grids and GeoTiffs for
##'  square grids.
##'
##'@author Pascal Title
##'
##'
##' @examples
##' \donttest{
##' tamiasEPM
##' tamiasEPM2 <- createEPMgrid(tamiasPolyList, resolution = 50000,
##' cellType = 'square', method = 'centroid')
##'	writeEpmSpatial(tamiasEPM, filename = paste0(tempdir(), '/tamiasGrid.shp'))
##' writeEpmSpatial(tamiasEPM, filename = paste0(tempdir(), '/tamiasGrid.gpkg'))
##' unlink(paste0(tempdir(), '/tamiasGrid.gpkg'))
##' # will automatically append .gpkg
##' writeEpmSpatial(tamiasEPM, filename = paste0(tempdir(), '/tamiasGrid')) 
##'
##'	writeEpmSpatial(tamiasEPM2, filename = paste0(tempdir(), '/tamiasGrid.tif'))
##' unlink(paste0(tempdir(), '/tamiasGrid.tif'))
##' # will automatically append .tif
##' writeEpmSpatial(tamiasEPM2, filename = paste0(tempdir(), '/tamiasGrid'))
##'
##' # remove files generated by example
##' unlink(paste0(tempdir(), '/tamiasGrid', c('.dbf', '.gpkg', '.prj', '.shp', '.shx', '.tif')))
##' }
##'@export


writeEpmSpatial <- function(x, filename, ...) {

	if (!inherits(x, 'epmGrid')) {
		stop('x must be of class epmGrid.')
	}
	
	if (inherits(x[[1]], 'sf')) {
		if (!grepl('\\.\\w+$', filename, ignore.case = TRUE)) {
			filename <- paste0(filename, '.gpkg')
		}
		sf::st_write(x[[1]], dsn = filename, ...)
	} else {
		if (!grepl('\\.\\w+$', filename, ignore.case = TRUE)) {
			filename <- paste0(filename, '.tif')
		}		
		metric <- attributes(x)$metric
		terra::writeRaster(x[[1]][metric], filename, ...)
	}
}