autopal-deprecated: Optimize color palette for color vision deficiency

In qualpalr: Automatic Generation of Qualitative Color Palettes

Optimize color palette for color vision deficiency

Description

Deprecated: This function is deprecated and will be removed in a future release. There is no direct replacement.

Arguments

n	Number of colors to generate.
colorspace	Either 1) a list of three named numeric vectors: h (hue), s (saturation), and l (lightness), all of length 2 specifying a min and max value for the range. The values has to be in the range -360 to 360 for h, and 0 to 1 for s and l 2), or 2) a character vector specifying one of the predefined color spaces (see below).
cvd	Color vision deficiency adaptation to adapt the color palette to.
target	Target color difference.

Details

This function adapts color palettes to color vision deficiency (CVD) by optimizing the CVD severity to try reach a target color difference (DIN99d \delta E) of the user's choosing. Basically, it will choose a color palette that is as close as possible to the target \delta E by tweaking the CVD severity option in qualpal.

The rationale for this function is that when there are few colors in a color palette, there is no cost involved in adapting colors to CVD – the colors will still remain distinct. As more an more colors are added to the palette, however, adapting the color palette to CVD will eventually lead to colors that are too similar. This function gradually loosens the adaptation to CVDs by lowering the severity of CVD to simulate to before picking colors (the cvd_severity argument in qualpal)

Value

A list of class qualpal with the following components.

HSL	A matrix of the colors in the HSL color space.
RGB	A matrix of the colors in the sRGB color space.
hex	A character vector of the colors in hex notation.
de_DIN99d	A distance matrix of color differences according to the metric used. The name is misleading, bu kept for backwards compatibility.
hex	A character vector of the colors in hex notation.
min_de_DIN99d	The minimum pairwise DIN99d color difference among all colors in the palette.

See Also

qualpal-deprecated

qualpalr documentation built on Aug. 19, 2025, 1:14 a.m.