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Create an evacuation grid

Source: R/grid_region_escape.R
make_evac_grid.Rd

Creates polygon grid cells over a hazard/evacuation zone and masks the grid to the zone. The resulting cells can be intersected with buffered roads to create road-based origin points.

Usage

make_evac_grid(hazard_zone, resolution)

Arguments

hazard_zone

Hazard/evacuation zone as SpatVector, SpatRaster, or file path.

resolution

Grid cell resolution in map units. Use meters when data are in a projected CRS. Can be length 1 or 2.

Value

A polygon SpatVector grid clipped/masked to the hazard zone.

Examples

r <- terra::rast(nrows = 4, ncols = 4, xmin = 0, xmax = 4, ymin = 0, ymax = 4,
  vals = 1, crs = "EPSG:3857")
zone <- terra::as.polygons(r, dissolve = TRUE)
make_evac_grid(zone, resolution = 1)
#> class       : SpatVector
#> geometry    : polygons
#> dimensions  : 16, 0  (geometries, attributes)
#> extent      : 0, 4, 0, 4  (xmin, xmax, ymin, ymax)
#> coord. ref. : WGS 84 / Pseudo-Mercator (EPSG:3857)