build_palette: Build a palette

In pkuhnert/VizU: Visualizing uncertainty in spatial data

Build a palette

Description

This function prepares one of the four included colour palettes or builds a new colour palette.

Usage

build_palette(
  name,
  colrange = list(colour = NULL, difC = NULL),
  flipVertical = FALSE,
  flipHorizontal = FALSE,
  subtractive = FALSE
)

Arguments

name	Name of colour palette or usr for option to design a new palette. Colour palette names include BlueYellow, CyanMagenta, BlueRed and GreenBlue.
colrange	List with a character vector of length two called colour and a numeric vector of length two called difC. colour contains two colour names from the colours() range or valid hexadecimal colors. difC contains two integers (1, 2, 3 or 4), which control how much a colour changes in value across the grid. One corresponds with a small change in colour value, and four corresponds with a large change in colour value.
flipVertical	Whether the palette should be flipped vertically (ie. replace top portion with bottom portion)
flipHorizontal	Whether the palette should be flipped horizontally (ie. replace left portion with right portion)
subtractive	A logical evaluating to TRUE or FALSE indicating whether the colour mixing is subtractive or additive

Details

Note that colrange only needs to be specified if name = "usr." When choosing colours, it is best to avoid light colours or tints as these will lead to a colour palette lacking noticeable differences across the 3 x 3 colour grid. Note that subtractive = FALSE allows for additive colour mixing under the RGB colour wheel while subtractive = TRUE allows for subtractive colour mixing under the RYB colour wheel.

Examples

# use one of four prepared colour palettes
p <- build_palette(name = "CyanMagenta")
view(p)

# use subtractive colour mixing (blue + yellow = green)
p <- build_palette(name = "BlueYellow", subtractive = TRUE)
view(p)

# design a new palette
p <- build_palette(name = "usr", colrange =
 list(colour = c("darkblue", "chartreuse4"), difC = c(3, 4)))
view(p)

pkuhnert/VizU documentation built on March 19, 2024, 10:51 p.m.