"PictureMask"A description of a luminance mask.
content:Object of class "list". A list of "PictureContent"
objects that are use to define the mask. Typically objects that
actually draw content (e.g. a path or a rect).
signature(object = "PictureMask"): creates a mask object
for use with the gridSVG package. Not intended to be used
directly.
There are three arguments to this grobify method:
defsAn object of class "PictureDefinitions". This object is
primarily useful in conjunction with the gridSVG package.
gpFUNThis argument takes a function that takes a gpar object
and returns a modified gpar object. The default value
is the identity function.
extA character vector. See grid.picture for more
information on what this extension selection parameter means,
in addition to the valid values this argument takes.