R/bathy_to_spatraster.R

In EvolEcolGroup/pastclim: Manipulate Time Series of Climate Reconstructions

#' Cast `bathy` to `SpatRaster`
#'
#' This function converts a [`marmap::bathy`][`marmap::as.bathy()`] object to
#' a [`terra::SpatRaster`].
#'
#' @param bathy a [`marmap::bathy`][`marmap::as.bathy()`] to convert
#' @returns a [`terra::SpatRaster`] with the relief for the chosen region
#'
#' @keywords internal


bathy_to_spatraster <- function(bathy) {
  if (!requireNamespace("marmap", quietly = TRUE)) {
    message(
      "This function requires the 'marmap' package; install it with:\n",
      "install.packages('marmap')"
    )
    return(invisible())
  }

  if (!inherits(bathy, "bathy")) stop("Object is not of class bathy")

  lat <- as.numeric(colnames(bathy))
  lon <- as.numeric(rownames(bathy))

  r <- terra::rast(
    ncol = nrow(bathy), nrow = ncol(bathy),
    xmin = min(lon), xmax = max(lon),
    ymin = min(lat), ymax = max(lat)
  )
  terra::values(r) <- as.vector(bathy[, rev(seq_len(ncol(bathy)))])

  return(r)
}