The Okabe-Ito color palette was proposed by Okabe and Ito (2008) as a qualitative color palette that is accessible to people with a variety of forms of color vision deficiency. In addition to being accessible, it includes 9 vivid colors that are readily nameable and include colors that correspond to major primary and secondary colors (e.g., red, yellow, blue).

## Usage

scale_color_okabeito(
palette = "full",
reverse = FALSE,
order = 1:9,
aesthetics = "color",
...
)

scale_fill_okabeito(
palette = "full",
reverse = FALSE,
order = 1:9,
aesthetics = "fill",
...
)

scale_colour_okabeito(
palette = "full",
reverse = FALSE,
order = 1:9,
aesthetics = "color",
...
)

scale_colour_oi(
palette = "full",
reverse = FALSE,
order = 1:9,
aesthetics = "color",
...
)

scale_color_oi(
palette = "full",
reverse = FALSE,
order = 1:9,
aesthetics = "color",
...
)

scale_fill_oi(
palette = "full",
reverse = FALSE,
order = 1:9,
aesthetics = "fill",
...
)

## Arguments

palette

Character name of palette. Depending on the color scale, can be "full", "ice", "rainbow", "complement", "contrast", "light" (for dark themes), "black_first", full_original, or black_first_original.

reverse

Boolean indicating whether the palette should be reversed.

order

A vector of numbers from 1 to 9 indicating the order of colors to use (default: 1:9)

aesthetics

A vector of names of the aesthetics that this scale should be applied to (e.g., c('color', 'fill')).

...

Additional arguments to pass to colorRampPalette().

## Details

The Okabe-Ito palette is included in the base R grDevices::palette.colors(). These functions make this palette easier to use with ggplot2.

The original Okabe-Ito palette's "yellow" color is "#F0E442". This color is very bright and often does not show up well on white backgrounds (see here) for a discussion of this issue). Accordingly, by default, this function uses a darker more "amber" color for "yellow" ("#F5C710"). This color is the "yellow" color used in base R >4.0's default color palette. The palettes "full" and "black_first" use this darker yellow color. For the original yellow color suggested by Okabe and Ito ("#F0E442"), use palettes "full_original" or "black_first_original".

The Okabe-Ito palette is only available as a discrete palette. For color-accessible continuous variables, consider the viridis palettes.

## References

Okabe, M., & Ito, K. (2008). Color universal design (CUD): How to make figures and presentations that are friendly to colorblind people. https://jfly.uni-koeln.de/color/#pallet (Original work published 2002)

## Examples

library(ggplot2)
library(see)

ggplot(iris, aes(x = Species, y = Sepal.Length, fill = Species)) +
geom_boxplot() +
theme_modern() +
scale_fill_okabeito()

ggplot(iris, aes(x = Species, y = Sepal.Length, fill = Species)) +
geom_violin() +
theme_modern() +
scale_fill_oi(palette = "black_first")

# for the original brighter yellow color suggested by Okabe and Ito
ggplot(iris, aes(x = Species, y = Sepal.Length, fill = Species)) +
geom_violin() +
theme_modern() +
scale_fill_oi(palette = "full")

ggplot(iris, aes(x = Species, y = Sepal.Length, fill = Species)) +
geom_violin() +
theme_modern() +
scale_fill_oi(order = c(1, 5, 6, 2, 4, 3, 7))