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Create a road-constrained analysis mask

Source: R/roads_conductance.R
make_road_mask.Rd

Buffers the road network and candidate escape points, combines those buffered areas, and dissolves the result. The mask is used to constrain least-cost movement to the road/pathway network while allowing access around escape locations.

Usage

make_road_mask(
  roads,
  escape_points,
  road_buffer_m = 2,
  escape_buffer_m = 5,
  return_components = FALSE
)

Arguments

roads

Road/pathway network.

escape_points

Candidate escape/safety points.

road_buffer_m

Road buffer distance in map units, typically meters.

escape_buffer_m

Escape-point buffer distance in map units, typically meters.

return_components

Logical. If TRUE, return a list with the mask and component buffers.

Value

A dissolved road mask SpatVector, or a list when return_components = TRUE.

Examples

roads <- terra::vect(matrix(c(0, 1, 4, 1), ncol = 2, byrow = TRUE),
  type = "lines", crs = "EPSG:3857")
escape <- terra::vect(data.frame(x = 4, y = 1), geom = c("x", "y"), crs = "EPSG:3857")
make_road_mask(roads, escape, road_buffer_m = 0.1, escape_buffer_m = 0.2)
#> class       : SpatVector
#> geometry    : polygons
#> dimensions  : 1, 0  (geometries, attributes)
#> extent      : -0.1, 4.2, 0.8, 1.2  (xmin, xmax, ymin, ymax)
#> coord. ref. : WGS 84 / Pseudo-Mercator (EPSG:3857)