grobCoords Calculate Points on the Perimeter of a Grob

Description

These functions calculate points along the perimeter (or length) of a grob.

Usage

grobCoords(x, closed, ...)
grobPoints(x, closed, ...)
emptyCoords
isEmptyCoords(coords)

Arguments

x	A grob object.
closed	Whether we are asking for points along the perimeter of a closed object or points along the length of an open object. Some grobs (e.g., X-splines) can do both.
...	Arguments to be used by methods.
coords	A set of grob coordinates (as generated by grobCoords).

Details

Custom grobs can write their own methods for grobPoints.

The emptyCoords object can be used to return a "null" result (e.g., when asking for closed coordinates on an open line) and the isEmptyCoords function can be used to check for "null" results.

Value

A list of lists with components x and y. All locations are in inches relative to the current grid viewport.

Author(s)

Paul Murrell