The layer_sf()
function is a variant of layer()
meant to be used by
extension developers who are writing new sf-based geoms or stats.
The sf layer checks whether the data contains a geometry column, and
if one is found it is automatically mapped to the geometry
aesthetic.
layer_sf(
geom = NULL,
stat = NULL,
data = NULL,
mapping = NULL,
position = NULL,
params = list(),
inherit.aes = TRUE,
check.aes = TRUE,
check.param = TRUE,
show.legend = NA
)
The geometric object to use display the data
The statistical transformation to use on the data for this layer, as a string.
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)
).
Position adjustment, either as a string, or the result of a call to a position adjustment function.
Additional parameters to the geom
and stat
.
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()
.
If TRUE
, the default, will check that
supplied parameters and aesthetics are understood by the geom
or
stat
. Use FALSE
to suppress the checks.
If TRUE
, the default, will check that
supplied parameters and aesthetics are understood by the geom
or
stat
. Use FALSE
to suppress the checks.
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.