TikZ style text color from colormap adds text to nodes (can't use e.g. `text=.!50!black`)

Question

I have the following minimal example:

\documentclass[border=2mm]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat = 1.12}
\pgfplotsset{
  every axis/.style = {
    colormap name = viridis,
  },
}
\tikzset{
  cmapfill/.style = {
    color of colormap = {#1},
    draw = .!50!black,
    % text = .!50!black,
    fill = .!25!white,
  },
}
\begin{document}
\begin{tikzpicture}
\node[cmapfill = 200] (x) at (0, 0) {$x$};
\node[cmapfill = 700] (y) at (1, 0) {$y$};
\end{tikzpicture}
\end{document}

This works nicely, except that the text in the nodes has the color of the colormap, and I would like it to have the darker color .!50!black just like the border.

If I uncomment the text = .!50!black line then the text indeed has the desired color, however the string !50!black appears in the labels too.

How can I avoid changing the label text, but still change the text color?

. is not understood by TikZ but it uses it internally because that's what xcolor understands. It's not meant for end user. — percusse, Feb 15 '18 at 11:59
@PhelypeOleinik, #1 is not a color, it is the progress of the colormap. If I replace . with #1 I get Package xcolor Error: Undefined color '200'. — Ruud, Feb 15 '18 at 12:42
@percusse, the . was suggested in this answer. If it is not intended for users, what should I use instead? — Ruud, Feb 15 '18 at 12:43
@Ruud I said TikZ ;) not pgfplots. There is a different mechanism for text and path colors.` — percusse, Feb 15 '18 at 12:47

Hood Chatham · Accepted Answer · 2018-02-15T13:32:33.287

5

Move the color . into temp and then use temp in the mixes:

\documentclass[border=2mm]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat = 1.12}
\pgfplotsset{
  every axis/.style = {
    colormap name = viridis,
  },
}

\tikzset{
  cmapfill/.style = {
    color of colormap = {#1},
    /utils/exec={\colorlet{temp}{.}},
    draw = temp!50!black,
    text = temp!50!black,
    fill = temp!25!white,
  },
}
\begin{document}
\begin{tikzpicture}
\node[cmapfill = 200] (x) at (0, 0) {$x$};
\node[cmapfill = 700] (y) at (1, 0) {$y$};
\end{tikzpicture}
\end{document}

edited Feb 15 '18 at 13:32

answered Feb 15 '18 at 13:18

Hood Chatham

5,467

nice answer +1). however all explicit loading of tikz is superfluous. loading pgfplots is sufficient. – Zarko Feb 15 '18 at 13:30
@Zarko I just copied that stuff from his MWE. Edited both. – Hood Chatham Feb 15 '18 at 13:33

score 0 · Answer 2 · answered Feb 15 '18 at 13:21

Not an answer to the question, but as a workaround, I generated a list of pre-defined colors using Matplotlib, which is where pgfplots got the colormap from in the first place:

from matplotlib import cm
cmap = cm.get_cmap('viridis')
for z in range(0, 51):
  print('\\definecolor{{viridis{}}}{{rgb}}{{{},{},{}}}'.format(z, *cmap(z * 0.02)))

This prints

\definecolor{viridis0}{rgb}{0.267004,0.004874,0.329415}
...
\definecolor{viridis50}{rgb}{0.993248,0.906157,0.143936}

After defining

\tikzset{
  viridis/.style = {
    text = viridis#1!75!black,
    draw = viridis#1!75!black,
    fill = viridis#1!25!white,
  },
}

It can then be used as

\begin{tikzpicture}
\node[viridis = 10] (x) at (0, 0) {$x$};
\node[viridis = 35] (y) at (1, 0) {$y$};
\end{tikzpicture}

This works in TikZ without loading pgfplots at all.

TikZ style text color from colormap adds text to nodes (can't use e.g. `text=.!50!black`)

2 Answers2