ggplot2 Increase Color Palette Intensity

Confession: LLM (GLM-5.1) gave me a right direction.

Using scater::plotColData() function I create a violin plot of colData() of a TreeSummarizedExperiment object. However, the colors were a bit bleak and barely visible on the screen. ggplot2 book provides a solution using scale_fill_hue() function.

scale_colour_hue(
  h.start = 0,
  c = 150, # Increase intensity of colors
  l = 55,
...
) +

You can experiment with different c (chroma) and l (luminance) values.

plotColData(
  tse,
  "shannon_diversity",
  "id",
  color_by = "treatment",
  shape_by = "timepoint"
) +
  labs(x = "Id", y = "Shannon diversity") +
  scale_colour_hue(
    h.start = 0,
    c = 150, # Increase intensity of colors
    l = 55,
    name = "Treatment and timepoint",
  ) +
  guides(shape = guide_legend(title = "Timepoint")) +