| showViewport {grid} | R Documentation | 
Produces a graphical display of (by default) the current grid viewport tree. It is also possible to display only specific viewports. Each viewport is drawn as a rectangle and the leaf viewports are labelled with the viewport name.
showViewport(vp = NULL, recurse = TRUE, depth = NULL,
             newpage = FALSE, leaves = FALSE,
             col = rgb(0, 0, 1, 0.2), fill = rgb(0, 0, 1, 0.1),
             label = TRUE, nrow = 3, ncol = nrow)
vp | 
 If   | 
recurse | 
 Should the children of the specified viewport also be displayed?  | 
depth | 
 Only display viewports at the specified depth (may be a vector of depths).  | 
newpage | 
 Start a new page for the display? Otherwise, the viewports are displayed on top of the current plot.  | 
leaves | 
 Produce a matrix of smaller displays, with each leaf viewport in its own display.  | 
col | 
 The colour used to draw the border of the rectangle for each viewport and to draw the label for each viewport. If a vector, then the first colour is used for the top-level viewport, the second colour is used for its children, the third colour for their children, and so on.  | 
fill | 
 The colour used to fill each viewport.  May be a vector as per
  | 
label | 
 Should the viewports be labelled (with the viewport name)?  | 
nrow, ncol | 
 The number of rows and columns when   | 
viewport and
grid.show.viewport
showViewport(viewport(width=.5, height=.5))
showViewport(vpStack(viewport(width=.5, height=.5),
                     viewport(width=.5, height=.5)),
             newpage=TRUE)
showViewport(vpStack(viewport(width=.5, height=.5),
                     viewport(width=.5, height=.5)),
             fill=rgb(1:0, 0:1, 0, .1),
             newpage=TRUE)