choose_palette.RdA graphical user interface (GUI) for viewing, manipulating, and choosing HCL color palettes.
choose_palette(pal = diverging_hcl, n = 7L, parent = NULL, gui = "tcltk", ...)
hclwizard(n = 7L, gui = "shiny", ...)function; the initial palette, see ‘Value’ below. Only
used if gui = "tcltk".
integer; the initial number of colors in the palette.
tkwin; the GUI parent window. Only used if gui =
"tcltk".
character; GUI to use. Available options are tcltk and
shiny, see ‘Details’ below.
used for development purposes only.
Returns a palette-generating function with the selected arguments. Thus, the returned function takes an integer argument and returns the corresponding number of HCL colors by traversing HCL space through interpolation of the specified hue/chroma/luminance/power values.
Computes palettes based on the HCL (hue-chroma-luminance) color model (as
implemented by polarLUV). The GUIs interface the palette
functions qualitative_hcl for qualitative palettes,
sequential_hcl for sequential palettes with a single or
multiple hues, and diverging_hcl for diverging palettes (composed
from two single-hue sequential palettes).
Two different GUIs are implemented and can be selected using the function
input argument gui ("tcltk" or "shiny"). Both GUIs
allows for interactive modification of the arguments of the respective
palette-generating functions, i.e., starting/ending hue (wavelength, type of
color), minimal/maximal chroma (colorfulness), minimal maximal luminance
(brightness, amount of gray), and a power transformations that control how
quickly/slowly chroma and/or luminance are changed through the palette.
Subsets of the parameters may not be applicable depending on the type of
palette chosen. See qualitative_hcl and Zeileis et al. (2009, 2019) for
a more detailed explanation of the different arguments. Stauffer et al.
(2015) provide more examples and guidance.
Optionally, active palette can be illustrated by using a range of examples such as a map, heatmap, scatter plot, perspective 3D surface etc.
To demonstrate different types of deficiencies, the active palette may be
desaturated (emulating printing on a grayscale printer) and collapsed to
emulate different types of color-blindness (without red-green or green-blue
contrasts) using the simulate_cvd functions.
choose_palette by default starts the Tcl/Tk version of the GUI while
hclwizard by default starts the shiny version. hcl_wizard is
an alias for hclwizard.
Zeileis A, Hornik K, Murrell P (2009). Escaping RGBland: Selecting Colors for Statistical Graphics. Computational Statistics & Data Analysis, 53, 3259--3270. doi:10.1016/j.csda.2008.11.033 Preprint available from https://www.zeileis.org/papers/Zeileis+Hornik+Murrell-2009.pdf.
Stauffer R, Mayr GJ, Dabernig M, Zeileis A (2015). Somewhere over the Rainbow: How to Make Effective Use of Colors in Meteorological Visualizations. Bulletin of the American Meteorological Society, 96(2), 203--216. doi:10.1175/BAMS-D-13-00155.1
Zeileis A, Fisher JC, Hornik K, Ihaka R, McWhite CD, Murrell P, Stauffer R, Wilke CO (2020). “colorspace: A Toolbox for Manipulating and Assessing Colors and Palettes.” Journal of Statistical Software, 96(1), 1--49. doi:10.18637/jss.v096.i01
if(interactive()) {
## Using tcltk GUI
pal <- choose_palette()
## or equivalently: hclwizard(gui = "tcltk")
## Using shiny GUI
pal <- hclwizard()
## or equivalently: choose_palette(gui = "shiny")
## use resulting palette function
filled.contour(volcano, color.palette = pal, asp = 1)
}