Plot a resistance surface with a consistent colour scheme

Draws a resistance SpatRaster using a shared colour scheme (green for low resistance through red for high resistance) with a discrete-swatch legend placed to the left of the panel. Each resistance value is mapped to a fixed colour so that the same value appears identical across figures, which is useful when comparing several landscapes or when pairing a resistance surface with a network plot (see plotWithResistance()).

Usage

plotResistance(x, maxResistance = 12L)

Arguments

x: A resistance SpatRaster, e.g. the cost surface passed to MPG().
maxResistance: Integer. The resistance value mapped to the top (red) end of the colour ramp; values from 1 to maxResistance receive fixed colours so the scheme stays consistent across surfaces. Defaults to 12, and is automatically raised to the largest value present in x if that exceeds it.

Value

A ggplot2::ggplot() object.

Author

Alex M Chubaty

Examples

tiny <- terra::rast(
  system.file("extdata", "tiny.asc", package = "grainscape", mustWork = TRUE)
)
tinyCost <- terra::classify(tiny, rcl = cbind(c(1, 2, 3, 4), c(1, 5, 10, 12)))
plotResistance(tinyCost)