shade: The shade class

In shades: Simple Colour Manipulation

The shade class

Description

Objects of class "shade" are simply standard R character vectors representing one or more 8-bit (s)RGB colours in CSS-like hex format, but with extra attributes giving the current colour space and coordinates. Opacity values are also supported.

Usage

shade(x, ...)

## S3 method for class 'shade'
shade(x, ...)

## S3 method for class 'color'
shade(x, ...)

## S3 method for class 'matrix'
shade(x, space = "sRGB", alpha = NULL, ...)

## S3 method for class 'character'
shade(x, ...)

## Default S3 method:
shade(x, ...)

shades(...)

## S3 method for class 'shade'
print(x, ...)

## S3 method for class 'shade'
x[i]

## S3 replacement method for class 'shade'
x[i] <- value

## S3 method for class 'shade'
c(...)

## S3 method for class 'shade'
rep(x, ...)

## S3 method for class 'shade'
rev(x)

## S3 method for class 'shade'
x == y

## S3 method for class 'shade'
x != y

## S3 method for class 'shade'
all.equal(target, current, hexonly = FALSE, ...)

Arguments

x, y	R objects, or "shade" objects for methods.
...	For shade(), additional parameters to methods. For shades() and c(), any number of colours in any acceptable form.
space	For a matrix, the space in which coordinates are being provided.
alpha	For a matrix, an associated vector of opacity values between 0 and 1, if required.
i	An index vector.
value	A vector of replacement colours.
target, current	Shade vectors to compare.
hexonly	If TRUE, compare only on the basis of the hex strings. Otherwise test for equal coordinates.

Details

The shade() function creates a colour vector from a single main argument plus method-specific arguments where appropriate. The shades() function provides an alternative interface that converts each of its arguments to shades, with direct inline naming, and then concatenates them.

Comparison between "shade" objects x and y is achieved by converting y (the second argument) into the colour space of x and then comparing coordinates, after any clipping.

Value

A character vector of class "shade", with additional attributes as follows.

space	A string naming a colour space.
coords	A matrix giving colour coordinates in the relevant space, one colour per row.
alpha	A numeric vector of alpha (opacity) values between 0 and 1, one value per element of the vector. If not present then full opacity is assumed for every element.
names	A character vector of element names, in the usual R convention. If not present then the object is unnamed.

Note

When concatenating, shades that are all from the same space will remain in that space, but shades from different spaces will be warped to "XYZ" space.

Author(s)

Jon Clayden [e-mail]

Examples

s <- shade(c("red", "green", "blue"))
s[1]
s[1] <- "pink"

shades documentation built on July 3, 2026, 1:07 a.m.