R: Windows graphics devices

windows {grDevices}

R Documentation

Windows graphics devices

Description

A graphics device is opened. For windows, win.graph, x11 and X11 this is a graphics window on the current Windows display: the multiple names are for compatibility with other systems. win.metafile prints to a file and win.print to the Windows print system.

Usage

windows(width = 7, height = 7, pointsize = 12,
        record = getOption("graphics.record"),
        rescale = c("R", "fit", "fixed"), xpinch, ypinch,
        bg = "transparent", canvas = "white",
        gamma = getOption("gamma"), xpos = NA, ypos = NA,
        buffered = getOption("windowsBuffered"),
        restoreConsole = FALSE)

win.graph(width = 7, height = 7, pointsize = 12,
          restoreConsole = FALSE)
x11(width = 7, height = 7, pointsize = 12, restoreConsole = FALSE)
X11(width = 7, height = 7, pointsize = 12, restoreConsole = FALSE)

win.metafile(filename = "", width = 7, height = 7, pointsize = 12,
             restoreConsole = TRUE)

win.print(width = 7, height = 7, pointsize = 12, printer = "",
          restoreConsole = TRUE)

Arguments

`width, height`	the (nominal) width and height of the canvas of the plotting window in inches.
`pointsize`	the default pointsize of plotted text. Values are rounded to the nearest integer: values less than or equal to zero are reset to 12.
`record`	logical: sets the initial state of the flag for recording plots.
`rescale`	controls the action for resizing plots.
`xpinch, ypinch`	double. Pixels per inch, horizontally and vertically.
`bg`	color. The default background color.
`canvas`	color. The color of the canvas which is visible when the background color is transparent.
`gamma`	the gamma correction factor. This value is used to ensure that the colors perceived are linearly related to RGB values (see `hsv`). By default this is taken from `options("gamma")`, or is 1 (no correction) if that is unset (the usual case).
`xpos, ypos`	integer. Position of the top left of the window, in pixels. Negative values are taken from the opposite edge of the monitor. Missing values meant take the default from the ‘`Rconsole`’ file, which in turn defaults to `xpos=-25, ypos=0`: this puts the right edge of the window 25 pixels from the right edge of the monitor.
`buffered`	logical. Should the screen output be double-buffered?
`filename`	the name of the output file: it will be an enhanced Windows metafile, usually given extension `.emf` or `.wmf`. Up to 511 characters are allowed. The page number is substituted if an integer format is included in the character string. (The result must be less than 600 characters long.) The default, `""`, means the clipboard.
`printer`	The name of a printer as known to Windows. The default causes a dialog box to come for the user to choose a printer.
`restoreConsole`	logical: see the Details below.

Details

All these devices are implemented as windows devices, the display parameter selects which is actually used.

The size of a window is computed from information provided about the display: it depends on the system being configured accurately. By default a screen device asks Windows for the number of pixels per inch. This can be overridden (it is often wrong) by specifying xpinch and ypinch or the corresponding options "xpinch" and "ypinch".

A graphics window is not allowed to be specified at more that 85% of the screen width or height: the width and height are rescaled proportionally. The window can be resized to a larger size. In MDI mode, the limit is 85% of the MDI client region.

If the filename is omitted for a win.metafile device, the output is copied to the clipboard when the device is closed.

If a screen device is re-sized, the default behaviour is to redraw the plot(s) as if the new size had been specified originally. Using "fit" will rescale the existing plot(s) to fit the new device region, preserving the aspect ratio. Using "fixed" will leave the plot size unchanged, adding scrollbars if part of the plot is obscured.

A graphics window will never be created at more that 85% of the screen width or height, but can be resized to a larger size. For the first two rescale options the width and height are rescaled proportionally if necessary, and if rescale = "fit" the plot(s) are rescaled accordingly. If rescale = "fixed" the initially displayed portion is selected within these constraints, separately for width and height.

Using strwidth or strheight after a window has been rescaled (when using "fit") gives dimensions in the original units, but only approximately as they are derived from the metrics of the rescaled fonts (which are in integer sizes)

The displayed region may be bigger than the ‘paper’ size, and areas outside the ‘paper’ are coloured in the Windows application background colour. Graphics parameters such as "din" refer to the scaled plot if rescaling is in effect.

The different colours need to be distinguished carefully. The area outside the device region is coloured in the Windows application background colour. The device region is coloured in the canvas colour. This is over-painted by the background colour of a plot when a new page is called for, but that background colour can be transparent (and is by default). The difference between setting the canvas colour and the background colour is that when the device is copied the background colour is copied but the canvas colour is not.

Recorded plot histories are of class "SavedPlots". They have a print method, and a subset method. As the individual plots are of class "recordedplot" they can be replayed by printing them: see recordPlot. The active plot history is stored in variable .SavedPlots in the workspace.

When a screen device is double-buffered (the default) the screen is updated 100ms after last plotting call or every 500ms during continuous plotting. These times can be altered by setting options("windowsTimeout") to a vector of two integers before opening the device.

The font used for text drawn in a Windows device may be controlled in two ways. The file RHOME\etc\Rdevga can be used to specify mappings for par(font=) (in the graphics package). Alternatively, a device-independent R graphics font family can be specified (e.g., via par(family=) in the graphics package) and this will be mapped via the Windows font database (see windowsFonts).

Line widths as controlled by par(lwd=) are in multiples of 1/96inch. Multiples less than 1 are allowed, down to one pixel width.

pch="." with cex = 1 corresponds to a rectangle of sides the larger of one pixel and 0.01 inch.

For win.metafile only one plot is allowed per file, and Windows seems to disallow reusing the file. So the only way to allow multiple plots is to use a parametrized filename as in the example.

The restoreConsole argument is a temporary fix for a problem in the current implementation of several Windows graphics devices, and is likely to be removed in an upcoming release. If set to FALSE, the console will not receive the focus after the new device is opened.

Value

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

Examples

## Not run: 
## A series of plots written to a sequence of metafiles
win.metafile("Rplot%02d.wmf", pointsize = 10)
## End(Not run)

[Package grDevices version 2.4.1 Index]