Merge polygons (or polygon files) to form a single minimum convex polygon (mcp)

Primary use is to create a predict boundary for prep_sdm(), merging (an existing) minimum convex polygon with other sources of taxa distribution and clipping to a (usually coastal) boundary. The predict boundary is then used for generation of background points and for masking the 'full' predict (to the extent of the environmental variables.

Usage

make_predict_boundary(
  poly_list,
  buffer_list = NULL,
  out_file = tempfile(),
  col_name = "taxa",
  col_name_val = "boundary",
  clip = NULL,
  out_crs,
  return_poly = FALSE,
  force_new = FALSE,
  dens_int = NULL
)

Arguments

poly_list: List of paths or list of sf.
buffer_list: List, of length 1 or the same length as poly_list, specifying the distance to buffer each incoming element of poly_list. Buffering occurs after transformation to out_crs.
out_file: Character name of file to save
col_name: Name of column to create in the resulting mcp
col_name_val: Value to provide in the column in the resulting mcp
clip: sf. Clip the resulting mcp back to this.
out_crs: Numeric. epsg code
return_poly: Logical. Return the mcp, or alternatively out_file
force_new: Logical. If out_file exists, recreate it?
dens_int: Numeric. terra::densify() interval argument ("positive number, specifying the desired minimum distance between nodes. The unit is meter for lonlat data, and in the linear unit of the crs for planar data"). Set to NULL to not densify.

Value

If return_poly, sf, else out_file. .parquet mcp written to out_file