R/geomorpho_altrel.R

In elpidiofilho/mdsFuncs: Auxiliar functions to pre-process raster data and modelling with machine learning models using caret package

#' relative height metrics
#' @description calculates various relative height metrics
#'     Slope_Height, Valley_Depth, Normalized_Height,
#'     Standardized_Height, Mid_Slope_Positon using SAGA GIS
#' @param saga Rsagamcd object
#' @param mde SpatialRaster raster
#' @param todisk logical write the generated raster to disk
#' @param folder character folder name to save files
#' @return SpatialRaster with 5 layers
#' @export
#' @importFrom Rsagacmd saga_gis
#' @examples
#' # library(rsagacmd)
#' # saga <- saga_gis()
#' # frel <- geomorpho_altrel (saga, mde = dem, folder = './morpho',
#' #                          todisk = TRUE)
geomorpho_altrel <- function(saga, mde, todisk = FALSE, folder = NULL) {
  if (todisk == TRUE & is.null(folder)) {
    stop("if todisk = TRUE a folder name must be defined")
  }
  clr <- class(mde)
  if (clr[1] == "RasterLayer") {
    r <- rast(r)
  } else {
    if (clr[1] != "SpatRaster") {
      stop("mde must be in one of formats  RasterLayer,
           or SpatRaster")
    }
  }
  if (is.na(terra::crs(r))) {
    stop("r does not have a coordinate system")
  }
  relheights <- saga$ta_morphometry$relative_heights_and_slope_positions(dem = mde)
  nm <- c(
    "Slope_Height", "Valley_Depth", "Normalized_Height",
    "Standardized_Height", "Mid_Slope_Positon"
  )
  names(relheights) <- nm
  if (todisk == TRUE) {
    list_to_fileraster(terrain = relheights, path = folder)
  }
  for (i in 1:length(nm)) {
    names(relheights[[i]]) <- nm[i]
  }
  return(relheights)
}



#' Title convert lista de rasters em uma pilha de rasters
#' @param terrain list or SpatRaster
#' @param path character folder
#' @return SpatRaster
#' @importFrom terra rast setMinMax nlyr writeRaster
#' @importFrom here here
#' @importFrom sf write_sf
#' @examples
#' # rl = list_to_fileraster(alrel, "morpho")
list_to_fileraster <- function(terrain, path) {
  if (class(terrain) == "list") {
    nl <- length(terrain)
  } else {
    if (class(terrain) == "RasterLayer") {
      nm <- names(terrain)
      terrain <- terra::rast(terrain)
      names(terrain) <- nm
      terra::setMinMax(terrain)

      nl <- 1
    } else {
      if (class(terrain) == "SpatRaster") {
        nl <- terra::nlyr(terrain)
      }
    }
  }

  for (i in 1:nl) {
    rt <- terrain[[i]]
    cl <- class(rt)
    if (cl[1] == "RasterLayer" | cl[1] == "SpatRaster") {
      if (cl[1] == "RasterLayer") {
        rt <- rast(rt)
      }
      names(rt) <- paste0(names(terrain)[i])
      fn <- paste0(names(terrain)[i], ".tif")
      fp <- here::here(path, fn)
      print(fp)
      terra::setMinMax(rt)
      terra::writeRaster(rt, filename = fp, overwrite = TRUE)
    } else {
      fn <- paste0(names(terrain)[i], ".shp")
      fp <- here::here(path, fn)
      print(fp)
      sf::write_sf(rt, fp, append = FALSE)
    }
  }
}