\HeaderA{dev2}{Copy Graphics Between Multiple Devices}{dev2}
\aliasA{dev.control}{dev2}{dev.control}
\aliasA{dev.copy}{dev2}{dev.copy}
\aliasA{dev.copy2eps}{dev2}{dev.copy2eps}
\aliasA{dev.print}{dev2}{dev.print}
\keyword{device}{dev2}
\begin{Description}\relax
\code{dev.copy} copies the graphics contents of the current device
to the device specified by \code{which} or to a new device which has
been created by the function specified by \code{device} (it is an
error to specify both \code{which} and \code{device}).  (If recording
is off on the current device, there are no contents to copy: this will
result in no plot or an empty plot.)
The device copied to becomes the current device.

\code{dev.print} copies the graphics contents of the current device
to a new device which has been created by the function specified by
\code{device} and then shuts the new device.

\code{dev.copy2eps} is similar to \code{dev.print} but produces an
EPSF output file, in portrait orientation (\code{horizontal = FALSE})

\code{dev.control} allows the user to control the recording of
graphics operations in a device.  If \code{displaylist} is \code{"inhibit"}
(\code{"enable")} then recording is turned off (on). It is only safe
to change this at the beginning of a plot (just before or just after a
new page).  Initially recording is on for screen devices, and off for
print devices.
\end{Description}
\begin{Usage}
\begin{verbatim}
dev.copy(device, ..., which = dev.next())
dev.print(device = postscript, ...)
dev.copy2eps(...)
dev.control(displaylist = c("inhibit", "enable"))
\end{verbatim}
\end{Usage}
\begin{Arguments}
\begin{ldescription}
\item[\code{device}] A device function (e.g., \code{x11},
\code{postscript}, \ldots)
\item[\code{...}] Arguments to the \code{device} function above: for
\code{dev.copy2eps} arguments to \code{\LinkA{postscript}{postscript}} and for
\code{dev.copy2pdf}, arguments to \code{\LinkA{pdf}{pdf}}.
For \code{dev.print}, this includes \code{which} and by default any
\code{\LinkA{postscript}{postscript}} arguments.
\item[\code{which}] A device number specifying the device to copy to.
\item[\code{displaylist}] A character string: the only valid values are
\code{"inhibit"} and \code{"enable"}.
\end{ldescription}
\end{Arguments}
\begin{Details}\relax
Note that these functions copy the \emph{device region} and not a
plot: the background colour of the device surface is part of what is
copied. Most screen devices default to a transparent background, which
is probably not what is needed when copying to a device such as
\code{\LinkA{png}{png}}.

For \code{dev.copy2eps} and \code{dev.copy2pdf},  \code{width} and
\code{height} are taken from the current device unless otherwise
specified.  If just one of \code{width} and \code{height} is
specified, the other is adjusted to preserve the aspect ratio of the
device being copied.  The default file name is \code{Rplot.eps} or
\code{Rplot.pdf}, and can be overridden by specifying a \code{file}
argument.

The default for \code{dev.print} is to produce and print a postscript
copy, if \code{\LinkA{options}{options}("printcmd")} is set suitably.


\code{dev.print} is most useful for producing a postscript print
(its default) when the following applies.  Unless
\code{file} is specified, the plot will be printed.  Unless
\code{width}, \code{height} and \code{pointsize} are specified
the plot dimensions will be taken from the current device, shrunk
if necessary to fit on the paper. (\code{pointsize} is rescaled if the
plot is shrunk.)  If \code{horizontal} is not specified and the plot
can be printed at full size by switching its value this is done
instead of shrinking the plot region.

If \code{dev.print} is used with a specified \code{device} (even
\code{postscript}) it sets the width and height in the same way as
\code{dev.copy2eps}.  This will not be appropriate unless the device
specifies dimensions in inches, in particular not for
\code{png} and \code{jpeg}.
\end{Details}
\begin{Value}
\code{dev.copy} returns the name and number of the device which has
been copied to.

\code{dev.print}, \code{dev.copy2eps} and \code{dev.copy2pdf} return
the name and number of the device which has been copied from.
\end{Value}
\begin{Note}\relax
Most devices (including all screen devices) have a display list
which records all of the graphics operations that occur in the device.
\code{dev.copy} copies graphics contents by copying the display list
from one device to another device.  Also, automatic redrawing of
graphics contents following the resizing of a device depends on the
contents of the display list.

After the command \code{dev.control("inhibit")}, graphics operations
are not recorded in the display list so that \code{dev.copy} and
\code{dev.print} will not copy anything and the contents of a device
will not be redrawn automatically if the device is resized.

The recording of graphics operations is relatively expensive in
terms of memory so the command \code{dev.control("inhibit")} can be
useful if memory usage is an issue.
\end{Note}
\begin{SeeAlso}\relax
\code{\LinkA{dev.cur}{dev.cur}} and other \code{dev.xxx} functions
\end{SeeAlso}
\begin{Examples}
\begin{ExampleCode}
## Not run: 
x11()
plot(rnorm(10), main="Plot 1")
dev.copy(device=x11)
mtext("Copy 1", 3)
dev.print(width=6, height=6, horizontal=FALSE) # prints it
dev.off(dev.prev())
dev.off()
## End(Not run)
\end{ExampleCode}
\end{Examples}

