All stat_* functions (like stat_bin) return a layer that
contains a Stat* object (like StatBin). The Stat*
object is responsible for rendering the data in the plot.
Arguments
Details
Each of the Stat* objects is a ggproto object,
derived from the top-level Stat, and each implements various methods
and fields. To create a new type of Stat object, you typically will want to
implement one or more of the following: