library("ggplot2")
library("scales")

show_col(colorblind_pal()(8))
p <- ggplot(mtcars) +
  geom_point(aes(
    x = wt,
    y = mpg,
    colour = factor(gear)
  )) +
  facet_wrap(~am)
p + theme_igray() + scale_colour_colourblind()
