Support sf objects for maps?

[etiennebacher]

Hi @grantmcdermott, @vincentarelbundock and @zeileis, I'm just wondering whether support for sf objects is on the roadmap. ggplot2 can be quite slow when drawing maps with several elements (say all the US counties + fill by variable + points). To clarify, creating the map is not slow but printing it can easily take 15-20 seconds or more and I'm wondering if a base plot would be faster for this.

A complete support would probably be complicated, but here's a very simple example:

library(ggplot2)
library(sf)
#> Linking to GEOS 3.12.1, GDAL 3.8.4, PROJ 9.3.1; sf_use_s2() is TRUE

nc <- sf::st_read(system.file("shape/nc.shp", package = "sf"), quiet = TRUE)

ggplot(nc) +
  geom_sf(aes(fill = AREA))

nc[, "AREA", drop = FALSE] |> 
  plot()

Being able to do plt(~ AREA, fill = "by", type = "map") would be great (contrarily to the syntax for density plots, we'd only need to have one variable in the formula here).

[etiennebacher]

Just to clarify, in the end tinyplot would call sf:::plot.sf

[grantmcdermott]

Native sf support is something I'd love to support. See #159 (comment) for a proof of concept.

One annoyance we'd have to figure out is color scaling for continuous grouping variables, since polypaths aren't currently compatible with our gradient legend logic. I have an idea for a workaround, but won't have time to look into this properly for the next few weeks.

Thanks for putting it on my (our!) radar again.