Makie: RGB legend colors

General Usage
1

How do I create legend entries in Makie using RBG colors?

The following worked in CairoMakie 0.7:

using CairoMakie, ColorSchemes

f = Figure()
Axis(f[1, 1])
labelV = ["lbl $j" for j = 1 : 3];
n = length(labelV);
elements = [PolyElement(color = ColorSchemes.corkO[i]) for i in 1:n];
Legend(f[1,2], elements, labelV);
f

In CairoMakie 0.8, it appears that the RBG colors returned by the color scheme are ignored. Replacing with color = :red works.

For background: I am creating a legend for a grouped bar graph. The legend colors are meant to match the bar colors. If there is a more direct way of accomplishing this, than manually pulling colors from the color theme, that would also be helpful.

2

Huh that’s weird, can you try what happens if you wrap the color with RGBAf()?

3

No change. All legend entries show grey colors. To be clear, what I’m doing now replaces one line from my original example with

elements = [PolyElement(color = RGBAf(ColorSchemes.corkO[i])) for i in 1:n];

However, with another color scheme (.e.g. leonardo) the colors are shown correctly. So I’m marking this as solved.

Thanks.

4

Aha but cork is a colorscheme with lots of color entries, so just picking the first 3 or so will not give you different colors. You’d need to sample the colormap at range(0, 1, length = n)

5

If you look in this list you can see that for cork the categorical display looks continuous, so it just has a lot of colors stored in small increments Colors

6

Thanks - I should have put that into my MWE. In my actual code, this is taken care of properly.

It turns out that the actual issue is the plot theme. I ran my MWE in the environment of my plotting package, which had called set_theme!(theme_ggplot2()).

When I run in a “clean” environment or with another theme, it works all fine. Reviewing, I noticed that the example bar graph in the documentation has the same issue (legends are shown as gray boxes).

I should probably file an issue. Thanks again for your help.