prepare_spdf.R

# Prepare SpatialPolygonsDataFrame for plotting with ggplot2
# Follows https://github.com/hadley/ggplot2/wiki/plotting-polygon-shapefiles
# Assumes you are in Hadleyverse and already have dplyr loaded.

prepare_spdf <- function(spdf) {
  require(dplyr)
  reguire(ggplot2)
  spdf@data$id <- rownames(spdf@data)
  spdf.points <- ggplot2::fortify(spdf, region = "id")
  if (sum(is.na(spdf.points$hole))) {
    spdf.points <- spdf.points %>%
      dplyr::filter(hole == FALSE)
  }
  spdf.df <- dplyr::left_join(spdf.points, spdf@data, by = "id")
  return(spdf.df)
}