R/geom_rtile.R

In delabj/AfricaCountryBins: Create a countrybin map of Africa

# Stolen from statebins

geom_rtile <- function(mapping = NULL, data = NULL,
                       stat = "identity", position = "identity",
                       radius = grid::unit(6, "pt"),
                       ...,
                       na.rm = FALSE,
                       show.legend = NA,
                       inherit.aes = TRUE) {
  ggplot2::layer(
    data = data,
    mapping = mapping,
    stat = stat,
    geom = GeomRtile,
    position = position,
    show.legend = show.legend,
    inherit.aes = inherit.aes,
    params = list(
      radius = radius,
      na.rm = na.rm,
      ...
    )
  )
}

GeomRtile <- ggplot2::ggproto("GeomRtile", GeomRrect,

                              extra_params = c("na.rm", "width", "height"),

                              setup_data = function(data, params) {
                                data$width <- data$width %||% params$width %||% ggplot2::resolution(data$x, FALSE)
                                data$height <- data$height %||% params$height %||% ggplot2::resolution(data$y, FALSE)

                                transform(data,
                                          xmin = x - width / 2,  xmax = x + width / 2,  width = NULL,
                                          ymin = y - height / 2, ymax = y + height / 2, height = NULL
                                )
                              },

                              default_aes = ggplot2::aes(
                                fill = "grey20", colour = NA, size = 0.1, linetype = 1, alpha = NA
                              ),

                              required_aes = c("x", "y"),

                              draw_key = ggplot2::draw_key_polygon

)