convertNative {grid}R Documentation

Convert a Unit Object to Native units

Description

This function is deprecated in grid version 0.8 and will be made defunct in grid version 1.9

You should use the convertUnit() function or one of its close allies instead.

This function returns a numeric vector containing the specified x or y locations or dimensions, converted to "user" or "data" units, relative to the current viewport.

Usage

convertNative(unit, dimension="x", type="location")

Arguments

unit A unit object.
dimension Either "x" or "y".
type Either "location" or "dimension".

Value

A numeric vector.

WARNING

If you draw objects based on output from these conversion functions, then resize your device, the objects will be drawn incorrectly – the base R display list will not recalculate these conversions. This means that you can only rely on the results of these calculations if the size of your device is fixed.

Author(s)

Paul Murrell

See Also

grid.convert, unit

Examples

grid.newpage()
pushViewport(viewport(width=unit(.5, "npc"),
                       height=unit(.5, "npc")))
grid.rect()
w <- convertNative(unit(1, "inches"))
h <- convertNative(unit(1, "inches"), "y")
# This rectangle starts off life as 1in square, but if you
# resize the device it will no longer be 1in square
grid.rect(width=unit(w, "native"), height=unit(h, "native"),
          gp=gpar(col="red"))
popViewport(1)

# How to use grid.convert(), etc instead
convertNative(unit(1, "inches")) ==
  convertX(unit(1, "inches"), "native", valueOnly=TRUE)
convertNative(unit(1, "inches"), "y", "dimension") ==
  convertHeight(unit(1, "inches"), "native", valueOnly=TRUE)

[Package grid version 2.4.1 Index]