xside refers to the api of ggside. Any geom_ with
xside will plot its respective geometry along the x-axis
per facet panel. By default the xside panel will plot above the main
panel. This xside panel will always share the same scale as it's main
panel, but is expected to have a separate y-axis scaling.
New Aesthetics
All xside Geometries have xfill, xcolour/xcolor available for
aesthetic mappings. These mappings behave exactly like the default
counterparts except that they are considered separate scales. All
xside geometries will use xfill over fill, but will default
to fill if xfill is not provided. The same goes for xcolour in
respects to colour. This comes in handy if you wish to map both fill
to one geometry as continuous, you can still map xfill for a separate
xside geometry without conflicts. See more information in
vignette("ggside").
Exported Geometries
The following are the xside variants of the ggplot2
Geometries