grid.newpage(recording = TRUE)gpar("fill")), which is often transparent. For devices
with a canvas colour (the on-screen devices X11,
windows and quartz), the page is first painted with the
canvas colour and then the background colour. There are two hooks called "before.grid.newpage" and
"grid.newpage" (see setHook). The latter
is used in the testing code to annotate the new page. The hook
function(s) are called with no argument. (If the value is a character
string, get is called on it from within the grid
namespace.)