grDevices (version 3.2.0)

dev.capabilities: Query Capabilities of the Current Graphics Device

Description

Query the capabilities of the current graphics device.

Usage

dev.capabilities(what = NULL)

Arguments

what

a character vector partially matching the names of the components listed in section ‘Value’, or NULL which lists all available capabilities.

Value

A named list with some or all of the following components, any of which may take value NA:

semiTransparency

logical: Does the device support semi-transparent colours?

transparentBackground

character: Does the device support (semi)-transparent backgrounds? Possible values are "no", "fully" (only full transparency) and "semi" (semi-transparent background colours are supported).

rasterImage

character: To what extent does the device support raster images as used by rasterImage and grid.raster? Possible values "no", "yes" and "non-missing" (support only for arrays without any missing values).

capture

logical: Does the current device support raster capture as used by grid.cap?

locator

logical: Does the current device support locator and identify?

events

character: Which events can be generated on this device? Currently this will be a subset of c("MouseDown", "MouseMove", "MouseUp", "Keybd"), but other events may be supported in the future.

Details

The capabilities have to be specified by the author of the graphics device, unless they can be deduced from missing hooks. Thus they will often by returned as NA, and may reflect the maximal capabilities of the underlying device where several output formats are supported by one device.

Most recent devices support semi-transparent colours provided the graphics format does (which PostScript does not). On the other hand, relatively few graphics formats support (fully or semi-) transparent backgrounds: generally the latter is found only in PDF and PNG plots.

See Also

See getGraphicsEvent for details on interactive events.

Examples

dev.capabilities()