quartz {grDevices} | R Documentation

## MacOS X Quartz Device

### Description

`quartz` starts a graphics device driver for the Mac OS X System. It supports plotting both to the screen (the default) and to various graphics file formats.

### Usage

    quartz(title, width, height, pointsize, family, fontsmooth,
           antialias, type, file = NULL, bg, canvas, dpi)

    quartz.options(..., reset = FALSE)

### Arguments

`title` | title for the Quartz window (applies to on-screen output only), default `"Quartz %d"`. A C-style format for an integer will be substituted by the device number (see the `file` argument to `postscript` for further details).
`width` | the width of the plotting area in inches. Default `7`.
`height` | the height of the plotting area in inches. Default `7`.
`pointsize` | the default pointsize to be used. Default `12`.
`family` | this is the family name of the font that will be used by the device. Default `"Helvetica"`.
`fontsmooth` | logical specifying if fonts should be smoothed. Default `TRUE`. Currently unused.
`antialias` | whether to use antialiasing. Default `TRUE`.
`type` | the type of output to use. See ‘Details’ for more information. Default `"native"`.
`file` | an optional target for the graphics device. The default, `NULL`, selects a default name where one is needed. See ‘Details’ for more information.
`bg` | the initial background colour to use for the device. Default `"transparent"`. An opaque colour such as `"white"` will normally be required on off-screen types that support transparency such as `"png"` and `"tiff"`.
`canvas` | canvas colour to use for an on-screen device. Default `"white"`, and will be forced to be an opaque colour.
`dpi` | resolution of the output. The default (`NA_real_`) for an on-screen display defaults to the resolution of the main screen, and to 72 dpi otherwise. See ‘Details’.
`...` | Any of the arguments to `quartz` except `file`.
`reset` | logical: should the defaults be reset to their defaults?

### Details

The defaults for all but one of the arguments of `quartz` are set by `quartz.options`: the ‘Arguments’ section gives the ‘factory-fresh’ defaults.

The Quartz graphics device supports a variety of output types. On-screen output types are `""` or `"native"` (picks the best possible on-screen output), `"Cocoa"` (Mac OS X 10.4 and later) and `"Carbon"` (not currently implemented – potentially Mac OS X 10.3 and earlier). Off-screen output types produce output files and utilize the `file` argument. `type = "pdf"` gives PDF output. The following bitmap formats may be supported (on OS X 10.4 and later): `"png"`, `"jpeg"`, `"jpg"`, `"jpeg2000"`, `"tif"`, `"tiff"`, `"gif"`, `"psd"` (Adobe Photoshop), `"bmp"` (Windows bitmap), `"sgi"` and `"pict"`. (The availability of some formats is OS-version-dependent.)

To reproduce the default of older Quartz devices on-screen, set `dpi = 72` (for a permanent solution set `quartz.options(dpi = 72)`).

The `file` argument is used for off-screen drawing. The actual file is only created when the device is closed (e.g. using `dev.off()`). For the bitmap devices, the page number is substituted if a C integer format is included in the character string, e.g. `Rplot%03d.png`. (The result must be less than `PATH_MAX` characters long, and may be truncated if not. See `postscript` for further details.) If a `file` argument is not supplied, the default is `Rplots.pdf` or `Rplot%03d.type`. Tilde expansion (see `path.expand`) is done.

If a device-independent R graphics font family is specified (e.g., via `par(family=)` in the graphics package), the Quartz device makes use of the Quartz font database (see `quartzFonts`) to convert the R graphics font family to a Quartz-specific font family description.

On-screen devices are launched with a semi-transparent canvas. Once a new plot is created, the canvas is first painted with the `canvas` colour and then the current background colour (which can be transparent or semi-transparent). Off-screen devices have no canvas colour, and so start with a transparent background where possible (e.g. `type = "png"` and `type = "tiff"`) – otherwise it appears that a solid white canvas is assumed in the Quartz code. PNG and TIFF files are saved with a dark grey matte which will show up in some viewers, including `Preview`.

`title` can be used for on-screen output. It must be a single character string with an optional integer printf-style format that will be substituted by the device number. It is also optionally used (without a format) to give a title to a PDF file.

Calling `quartz()` sets `.Device` to `"quartz"` for on-screen devices and to `"quartz_off_screen"` otherwise.

The font family chosen needs to cover the characters to be used: characters not in the font are rendered as empty oblongs. For non-Western-European languages something other than the default of `"Helvetica"` is likely to be needed—one choice for Chinese is `"MingLiU"`.

### Conventions

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

- The default device size is 7 inches square.

- Font sizes are in big points.

- The default font family is Helvetica.

- Line widths are a multiple of 1/96 inch with no minimum set by R.

- Circle radii are real-valued with no minimum set by R.

- Colours are specified as sRGB.

### See Also

`quartzFonts`, `Devices`.

`png` for way to access the bitmap types of this device via R's standard bitmap devices.

### Examples

    ## Not run:
    ## put something like this is your .Rprofile to customize the defaults
    setHook(packageEvent("grDevices", "onLoad"),
            function(...) grDevices::quartz.options(width = 8, height = 6,
                                                    pointsize = 10))

    ## End(Not run)

[Package grDevices version 2.15.2 Index]