cairo {grDevices} | R Documentation

## Cairo-based SVG, PDF and PostScript Graphics Devices

### Description

Graphics devices for SVG, PDF and PostScript graphics files.

### Usage

    svg(filename = if(onefile) "Rplots.svg" else "Rplot%03d.svg",
        width = 7, height = 7, pointsize = 12,
        onefile = FALSE, bg = "white", antialias)

    cairo_pdf(filename = if(onefile) "Rplots.pdf" else "Rplot%03d.pdf",
              width = 7, height = 7, pointsize = 12,
              onefile = FALSE, bg = "white", antialias)

    cairo_ps(filename = if(onefile) "Rplots.ps" else "Rplot%03d.ps",
             width = 7, height = 7, pointsize = 12,
             onefile = FALSE, bg = "white", antialias)

### Arguments

`filename` | the name of the output file. The page number is substituted if a C integer format is included in the character string, as in the default. (The result must be less than `PATH_MAX` characters long, and may be truncated if not. See `postscript` for further details.) Tilde expansion is performed where supported by the platform.
`width` | the width of the device in inches.
`height` | the height of the device in inches.
`pointsize` | the default pointsize of plotted text (in big points).
`onefile` | should all plots appear in one file or in separate files?
`bg` | the initial background colour: can be overridden by setting par("bg").
`antialias` | the type of anti-aliasing (if any) to be used. See `X11`.

### Details

SVG (Scalar Vector Graphics) is a W3C standard for vector graphics. See http://www.w3.org/Graphics/SVG/. The output is SVG version 1.1 for `onefile = FALSE` (the default), otherwise SVG 1.2. (Very few SVG viewers are capable of displaying multi-page SVG files.)

Note that unlike `postscript` and `pdf`, `cairo_pdf` and `cairo_ps` sometimes record bitmaps and not vector graphics: a resolution of 72dpi is used. On the other hand, they can (on suitable platforms) include a much wider range of UTF-8 glyphs, and embed the fonts used. They are somewhat experimental.

R can be compiled without support for any of these devices: this will be reported if you attempt to use them on a system where they are not supported. They all require cairo version 1.2 or later.

If you plot more than one page on one of these devices and do not include something like `%d` for the sequence number in `file` (or set `onefile=TRUE`) the file will contain the last page plotted.

The `cairo_ps` output is not yet encapsulated (that is coming in cairo 1.6).

There is full support of transparency, but using this is one of the things liable to trigger bitmap output (and will always do so for `cairo_ps`).

### Value

A plot device is opened: nothing is returned to the R interpreter.

### Conventions

This section describes the implementation of the conventions for graphics devices set out in the “R Internals Manual”.

- The default device size is in pixels (`svg`) or inches.
- Font sizes are in big points.
- The default font family is Helvetica.
- Line widths are multiples of 1/96 inch.
- Circle radii have a minumum of 1/72 inch.
- Colours are interpreted by the viewing application.

### See Also

`Devices`, `dev.print`, `pdf`, `postscript`

`capabilities` to see if cairo is supported.

[Package grDevices version 2.8.1 Index]