grid.grob {grid} | R Documentation |
These functions create grid graphical objects.
grid.grob(list.struct, cl = NULL, draw = TRUE) grob(..., name = NULL, gp = NULL, vp = NULL, cl = NULL) gTree(..., name = NULL, gp = NULL, vp = NULL, children = NULL, childrenvp = NULL, cl = NULL) grobTree(..., name = NULL, gp = NULL, vp = NULL, childrenvp = NULL, cl = NULL) childNames(gTree) gList(...) is.grob(x)
... |
For |
list.struct |
a |
name |
a character identifier for the grob. Used to find the grob on the display list and/or as a child of another grob. |
children |
a |
childrenvp |
a |
gp |
A gpar object, typically the output
from a call to the function |
vp |
a |
cl |
string giving the class attribute for the |
draw |
logical indicating whether to produce graphical output. |
gTree |
a |
x |
An R object. |
These functions can be used to create a basic "grob"
,
"gTree"
, or "gList"
object, or a new class derived from
one of these.
A grid graphical object (“grob”) is a description of a graphical
item. These basic classes provide default behaviour for
validating, drawing,
and modifying graphical objects. Both call the function
validDetails
to check that the object returned is coherent.
A "gTree"
can have other grobs as children; when a gTree is drawn, it
draws all of its children. Before drawing its children, a gTree
pushes its childrenvp
slot and then navigates back up (calls
upViewport
) so that the children can specify their location
within the childrenvp
via a vpPath
.
Grob names need not be unique in general, but all children of a
gTree must have different names.
A grob name can be any string, though it is not
advisable to use the gPath
separator (currently
::
) in grob names.
The function childNames
returns the names of the grobs
which are children of a gTree.
All grid primitives (grid.lines
, grid.rect
, ...)
and some higher-level grid components (e.g., grid.xaxis
and grid.yaxis
) are derived from these classes.
grobTree
is just a convenient wrapper for gTree
when the only components of the gTree are grobs (so all
unnamed arguments become children of the gTree).
grid.grob
is deprecated.
An R object of class "grob"
, a graphical object.
Paul Murrell
grid.draw
,
grid.edit
,
grid.get
.