Build layers to implement an inset-compatible geometry

For plotting, use geom_sf_inset() instead. This helper is intended to be used when implementing custom geometries based on geom_sf_inset() so that they can provide parameters to control the inset.

Usage

build_sf_inset_layers(
  data,
  mapping,
  stat,
  position,
  show.legend,
  inherit.aes,
  params,
  inset,
  map_base = "normal",
  map_inset = "auto"
)

Arguments

data

The data to be displayed in this layer. There are three options:

If NULL, the default, the data is inherited from the plot data as specified in the call to ggplot().

A data.frame, or other object, will override the plot data. All objects will be fortified to produce a data frame. See fortify() for which variables will be created.

A function will be called with a single argument, the plot data. The return value must be a data.frame, and will be used as the layer data. A function can be created from a formula (e.g. ~ head(.x, 10)).

mapping

Set of aesthetic mappings created by aes(). If specified and inherit.aes = TRUE (the default), it is combined with the default mapping at the top level of the plot. You must supply mapping if there is no plot mapping.

stat

The statistical transformation to use on the data for this layer, either as a ggproto Geom subclass or as a string naming the stat stripped of the stat_ prefix (e.g. "count" rather than "stat_count")

position

Position adjustment, either as a string naming the adjustment (e.g. "jitter" to use position_jitter), or the result of a call to a position adjustment function. Use the latter if you need to change the settings of the adjustment.

show.legend

logical. Should this layer be included in the legends? NA, the default, includes if any aesthetics are mapped. FALSE never includes, and TRUE always includes. It can also be a named logical vector to finely select the aesthetics to display.

inherit.aes

If FALSE, overrides the default aesthetics, rather than combining with them. This is most useful for helper functions that define both data and aesthetics and shouldn't inherit behaviour from the default plot specification, e.g. borders().

params

Additional parameters to the geom and stat.

inset

Inset configuration; see configure_inset(). If NA (the default), this is inherited from the coord (see coord_sf_inset()).

map_base

Controls the layer with the base map. Possible values are "normal" to create a layer as though the inset were not specified, "clip" to create a layer with the inset viewport cut out, and "none" to prevent the insertion of a layer for the base map.

map_inset

Controls the layer with the inset map. Possible values are "auto" to choose the behaviour based on whether inset is specified, "normal" to create a layer with the viewport cut out and transformed, and "none" to prevent the insertion of a layer for the viewport map.

Value

A ggplot layer, or a pair of layers.

Examples

my_custom_geom <- function(mapping = ggplot2::aes(),
                           data = NULL,
                           stat = "my_custom_stat",
                           position = "identity",
                           ...,
                           inset = NA,
                           map_base = "normal",
                           map_inset = "auto",
                           na.rm = TRUE,
                           inherit.aes = TRUE) {
  params <- rlang::list2(na.rm = na.rm, ...)
  build_sf_inset_layers(data = data, mapping = mapping,
                        stat = stat, position = position,
                        show.legend = show.legend,
                        inherit.aes = inherit.aes,
                        params = params,
                        inset = inset,
                        map_base = map_base,
                        map_inset = map_inset)
}