How to Export Maps

Timothée Giraud

2026-01-09

mf_svg() and mf_png() export maps in SVG and PNG formats, respectively.

SVG export is the perfect solution for editing maps with desktop vector graphics software, such as Inkscape. SVG is a vector graphics file format.
PNG export should be used for maps that do not require further modification. PNG is a raster graphics file format.

The width/height ratio of the exported map matches that of a spatial object. If width is specified, then height is deduced from the width/height ratio of x. Alternatively, if height is specified, then width is deduced from the width/height ratio of x.
This helps to produce maps without too much wasted space.

SVG Export

The SVG format is perfect for producing maps that need further editing or resizing.

library(mapsf)
mtq <- mf_get_mtq()
mf_svg(
  x = mtq,
  filename = "fig/wo_export_fixed_height.svg",
  height = 5,
)
mf_map(mtq)
mf_title(txt = "SVG export")
dev.off()

The default driver for building SVG files, grDevices::svg(), has limitations regarding speed, file size, editability, and font support. The svglite package aims to solve these issues. The svglite package is not lightweight in terms of dependencies, so it is not imported by mapsf, but rather suggested. However, we strongly recommend its use if the aim is to edit the maps after export.

PNG Export

In this example we only set the width of the exported figure.

mf_png(
  x = mtq,
  filename = "fig/wo_export_fixed_width.png",
  width = 500
)
mf_map(mtq)
mf_title(txt = "PNG export: width=500px, height=608px (deduced)", cex = 1)
dev.off()

In the following example, we used the “dracula” theme and we added space to the right of the plot (50% of x width) in order to get some extra space for the legend.

mf_theme("dracula")
mf_png(
  x = mtq,
  filename = "fig/wo_export_fixed_width_expand.png",
  width = 500,
  expandBB = c(0, 0, 0, .5)
)
mf_map(mtq, expandBB = c(0, 0, 0, .5))
mf_map(mtq, "POP", "prop", leg_pos = "right")
mf_title(txt = "PNG export: width=500px, height=425px (deduced)")
dev.off()