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.

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.

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-scren devices and to "quartz_off_screen" otherwise.

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 Arial.

• 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.

• Colour interpretation is by the viewer, including the screen display.

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 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)

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