Color of chess notation (xskak)

Question

I would like to set color for specific moves in \mainline, like \mainline{1. f4 e5 2. {\color{red} g4} Qh4#}.

Is is any way to change the color for some moves?

Answer 1

There is no natural way but you can try the following mix of using NAG's to start and stop colors and a hand made style. The main problem is to stop the color: skak (used by xskak) mixes the parsing and the printing and so grouping commands have a tendency to explode.

\documentclass[]{scrbook}
\usepackage{xskak,xcolor}

\newcommand\mycolor{}
%NAG to start color:
\expandafter\def\csname $100\endcsname{\gdef\mycolor{\color{red}}}
%NAG to stop color:
\expandafter\def\csname $101\endcsname{\gdef\mycolor{\color{black}}}


\xskaknewstyleitem[%
 whiteopen={.\,},
 beforewhite=\mycolor,
 beforeblack=\mycolor,
 blackopen={\ldots\,},
 afterwhite={\color{black}\ },
 beforenumber=\color{black},
 afterblack={\ }]{color}

\xskaknewstyle[level= 1,styleitem=color,font=\bfseries,
               level= 3,font=\itshape]{color}


\begin{document}
\newchessgame
\mainline[style=color]{1. f4 e5 $100 2.  e4 $101 e6 3. Nf3 $100 Nf6 4. d4 $101 d5}
\end{document}