Convert lake depth contours to a raster

Usage

contours_to_raster(
  shoreline,
  contours,
  depth_col = "depth",
  res = 10,
  crs = NULL,
  method = c("idw", "near"),
  idw_power = 2
)

Arguments

contours: An sf object containing depth contour lines or polygons, with a numeric depth attribute.
depth_col: Character. Name of the column in contours containing depth values.
res: Numeric. Output raster resolution in the CRS units (e.g. metres).
crs: An sf/terra-compatible CRS string, EPSG integer, or NULL to inherit from contours.
method: Character. Interpolation method passed to terra::interpIDW or "near" for nearest-contour assignment. Use "idw" (default) for smooth interpolation.
idw_power: Numeric. IDW power parameter (default 2).

Value

A terra::SpatRaster of interpolated depth values, masked to the lake boundary derived from the outermost contour.

Examples

if (FALSE) { # \dontrun{
  contours <- sf::st_read("lake_contours.gpkg")
  depth_raster <- contours_to_raster(contours, depth_col = "depth_m", res = 5)
  terra::plot(depth_raster)
} # }