as_colourspace: Collect channels into a single layer of a specific...

In ggfx: Pixel Filters for 'ggplot2' and 'grid'

Collect channels into a single layer of a specific colourspace

Description

If you need to work on single channels one by one you can use the different ch_*() selectors. If the result needs to be combined again into a colour layer you can use as_colourspace and pass in the required channels to make up the colourspace. By default the alpha channel will be created as the combination of the alpha channels from the provided channel layers. Alternatively you can set auto_opacity = FALSE and provide one additional channel which will then be used as alpha.

Usage

as_colourspace(
  ...,
  colourspace = "sRGB",
  auto_opacity = TRUE,
  id = NULL,
  include = is.null(id)
)

Arguments

...	A range of layers to combine. If there are no channel spec set the luminosity will be used
colourspace	Which colourspace should the provided colour channels be interpreted as coming from.
auto_opacity	Should the opacity be derived from the input layers or taken from a provided alpha channel
id	A string identifying this layer for later use
include	Should the layer itself be included in the graphic

Value

A list of Layer objects

See Also

Other layer references: as_group(), as_reference()

Examples

library(ggplot2)

segments <- data.frame(
  x = runif(300),
  y = runif(300),
  xend = runif(300),
  yend = runif(300)
)

# We use 'white' as that is the maximum value in all channels
ggplot(mapping = aes(x, y, xend = xend, yend = yend)) +
  as_colourspace(
    geom_segment(data = segments[1:100,], colour = 'white'),
    geom_segment(data = segments[101:200,], colour = 'white'),
    geom_segment(data = segments[201:300,], colour = 'white'),
    colourspace = 'CMY'
  )

ggfx documentation built on Aug. 22, 2022, 9:09 a.m.