annotation_scale and annotation_north_arrow appear in all facets

[adrfantini]

I often do faceted plotting with ggplot.
However, if using facets with annotations, such as annotation_scale and annotation_north_arrow, appear on all facets. How would it be possible to make them appear only once, other than using patchwork or similar, instead of facets?

[paleolimbot]

As I've written it, there isn't any way to change or omit the properties of a scalebar or north arrow on panels using facets. This is something I should fix! In annotation_map_tile() I've made some of the parameters aesthetics, which I will probably do with the location and width_hint parameters for the scale and north arrow geometries. Thank you for reporting this!

[paleolimbot]

Alright! This will be in the next version using syntax something like this:

library(tidyverse)
library(ggspatial)
  
  df <- tibble::tibble(
    facet_var = c("one", "two", "three", "four"),
    data = list(data.frame(x = 0:4, y = -(0:4)))
  ) %>%
    tidyr::unnest()

  scale_params <- tibble::tibble(
    facet_var = c("one", "two", "three"),
    width_hint = 0.25,
    style = c("bar", "ticks", "bar"),
    location = c("bl", "tr", "tl"),
    unit_category = c("metric", "imperial", "metric"),
    text_col = c("black", "red", "blue"),
    line_col = c("black", "red", "blue")
  )

  ggplot(df) +
    geom_point(aes(x, y)) +
    annotation_scale(
      aes(width_hint = width_hint, style = style, location = location, unit_category = unit_category,
          text_col = text_col, line_col = line_col),
      data = scale_params,
      plot_unit = "m"
    ) +
    facet_wrap(~facet_var) +
    coord_fixed()

Created on 2018-12-14 by the reprex
package (v0.2.0).

[adrfantini]

Awesome, thanks!

[neellab-umd]

Hi There - I have been trying to get the code in your 12/14/2018 comment to work with my data and I have cannot for the life of me get it to work. I also do not see anything about facets in the help for version 1.1.7. Before I try to make a reprex with my data, I wanted to see if what was posted in 2018 is what was implemented to get a scale bar in only one facet.

[bappa10085]

What about annotation_north_arrow? How can we add the annotation_north_arrow and annotation_scale outside of the map?