\Header{pdf}{PDF Graphics Device}
\keyword{device}{pdf}
\begin{Description}\relax
\code{pdf} starts the graphics device driver for producing PDF
graphics.\end{Description}
\begin{Usage}
\begin{verbatim}
pdf(file = ifelse(onefile, "Rplots.pdf", "Rplot%03d.pdf"),
    width = 6, height = 6, onefile = TRUE, family = "Helvetica",
    encoding, bg, fg, pointsize)
\end{verbatim}
\end{Usage}
\begin{Arguments}
\begin{ldescription}
\item[\code{file}] a character string giving the name of the file.
\item[\code{width, height}] the width and height of the graphics region in
inches.
\item[\code{onefile}] logical: if true (the default) allow multiple figures
in one file.  If false, generate a file name containing the page
number.
\item[\code{family}] the font family to be used, one of \code{"AvantGarde"},
\code{"Bookman"}, \code{"Courier"}, \code{"Helvetica"},
\code{"Helvetica-Narrow"}, \code{"NewCenturySchoolbook"},
\code{"Palatino"} or \code{"Times"}. 
\item[\code{encoding}] the name of an encoding file.  Defaults to
\code{"ISOLatin1.enc"}
in the \file{R\_HOME/afm} directory, which is used if the path does
not contain a path separator.  An extension \code{".enc"} can be
omitted.
\item[\code{pointsize}] the default point size to be used.
\item[\code{bg}] the default background color to be used.
\item[\code{fg}] the default foreground color to be used.
\end{ldescription}
\end{Arguments}
\begin{Details}\relax
\code{pdf()} opens the file \code{file} and the PDF commands needed to
plot any graphics requested are sent to that file.

See \code{\Link{postscript}} for details of encodings, as the internal
code is shared between the drivers.  The native PDF encoding is given
in file \file{PDFDoc.enc}.

\code{pdf} writes uncompressed PDF.  It is primarily intended for
producing PDF graphics for inclusion in other documents, and
PDF-includers such as \code{pdftex} are usually able to handle
compression.

At present the PDF is fairly simple, with each page being represented
as a single stream.  The \R{} graphics model does not distinguish
graphics objects at the level of the driver interface.\end{Details}
\begin{Note}\relax
Acrobat Reader does not use the fonts specified but rather emulates
them from multiple-master fonts.  This can be seen in imprecise
centring of characters, for example the multiply and divide signs in
Helvetica.\end{Note}
\begin{SeeAlso}\relax
\code{\Link{Devices}},
\code{\Link{postscript}}\end{SeeAlso}
\begin{Examples}
\begin{ExampleCode}

## Test function for encodings
TestChars <- function(encoding="ISOLatin1")
{
    pdf(encoding=encoding)
    par(pty="s")
    plot(c(0,15), c(0,15), type="n", xlab="", ylab="")
    title(paste("Centred chars in encoding", encoding))
    grid(15, 15, lty=1)
    for(i in c(32:255)) {
        x <- i 
        y <- i 
        points(x, y, pch=i)
    }
    dev.off()
}
## there will be many warnings.
TestChars("ISOLatin2")
## doesn't view properly in US-spec Acrobat 5.05, but gs7.04 works.
## Lots of characters are not centred.
\end{ExampleCode}
\end{Examples}

