xskak & chessboard & count of pieces

Question

Within used packages xskak and chessboard and an initialized game, how can I determine the count of white and black pieces of a given \newgame and how I can output the actual position of these pieces on the corresponding chessboard? I know that there is an argument of \getpieceslist for \chessboard, but how I can summarize with the help of TeX commands the pieces for white and black and how I can output these lists with the help of figure?

Answer 1

The option (not the command) getpiecelists give comma separated lists of positions. You must parse this list e.g. with \@for to count them:

\documentclass{article}
\usepackage{xskak,chessboard}
\begin{document}
\newchessgame
\chessboard[getpiecelists]%

\newcounter{countrook}
\setcounter{countrook}{0}

\makeatletter
 \@for\templist:=\cblistr \do {\stepcounter{countrook}}
\makeatother

Number of black rooks: \thecountrook. They are at the positions \cblistr.
\end{document}

Edit: You can try this to get the various counts (I also change the command so that \cblist... now it defined also for pieces which are not on the board):

\documentclass{article}
\usepackage{xskak,chessboard}

\makeatletter
\renewcommand\board@do@getpiecelists{%
 \setcounter{cnt@board@file}{\board@val@minfilenum}%
 \setcounter{cnt@board@rank}{\board@val@minranknum}%
 \edef\board@temp@curlist{% changed 3.2.2012 to parse all pieces.
 \board@skak@piececharlist}
 \@for\board@temp@piecechar:=\board@temp@curlist
  \do {%
   \expandafter\xdef\csname cblist\board@temp@piecechar\endcsname{}% 3.2.2012 global
   \expandafter\xdef\csname cblistnum\board@temp@piecechar\endcsname{0}% 3.2.2012 new
   \expandafter\def\csname board@temp@\board@temp@piecechar @comma\endcsname{}}%
 \xdef\cblistempty{}%
 \xdef\cblistnumempty{}% 3.2.2012
 \def\board@temp@empty@comma{}%
 \whiledo
  {\value{cnt@board@file}<\numexpr \board@val@maxfilenum+1\relax}%
  {\whiledo
   {\value{cnt@board@rank}<\numexpr \board@val@maxranknum+1\relax}%
   {\edef\board@temp@piecechar{%
     \csname
       board@val@f\the\c@cnt@board@file r\the\c@cnt@board@rank @piecechar\endcsname}%
   \edef\board@temp@curlist{%
    \csname cblist\board@temp@piecechar\endcsname}%
   \edef\board@temp@comma{%
    \csname board@temp@\board@temp@piecechar @comma\endcsname}%
   \expandafter\xdef\csname cblist\board@temp@piecechar \endcsname{%
    \board@temp@curlist
    \board@temp@comma
    \alph{cnt@board@file}\the\c@cnt@board@rank}%
   \expandafter\xdef\csname cblistnum\board@temp@piecechar\endcsname{\the\numexpr \csname cblistnum\board@temp@piecechar\endcsname +1}% 3.2.2012
   \expandafter\def
     \csname board@temp@\board@temp@piecechar @comma\endcsname
     {,}%
   \stepcounter{cnt@board@rank}}%
   \setcounter{cnt@board@rank}{\board@val@minranknum}%
   \stepcounter{cnt@board@file}}}
\makeatother
\begin{document}

\newchessgame
\chessboard[setpieces={Ke1,Ra1,Ra3,Ra5},getpiecelists,marginleft=false]

White king: \cblistnumK

White rooks: \cblistnumR

White pieces: \the\numexpr \cblistnumK + \cblistnumQ +\cblistnumR
+\cblistnumB + \cblistnumN + \cblistnumP\relax

empty fields: \cblistnumempty

\end{document}