cardsA4.tex

\documentclass[paper=a4]{scrartcl}
\usepackage[ngerman]{babel}

\input{common}

% set KOMA-Script text area
\areaset{210mm}{297mm}

% set PDF title
\hypersetup{pdftitle={\theda{Die Karten}}}

% read cards from file
\newcounter{cardImageNumber}
\newcounter{cardImageRow}
\newlength{\cardImageLeft}
\newlength{\cardImageBottom}
\newlength{\cardImageRight}
\newlength{\cardImageTop}

\IfFileExists{./cards.pdf}{
  \newcommand*{\cardImagePath}{cards.pdf}
}{
  \newcommand*{\cardImagePath}{cards.template.pdf}
}

\newcommand*{\cardImage}{%
  \setcounter{cardImageRow}{\thecardImageNumber/6}%
  \setlength{\cardImageLeft}{120mm*(\thecardImageNumber-6*\thecardImageRow)}%
  \setlength{\cardImageBottom}{120mm*(5-\thecardImageRow)}%
  \setlength{\cardImageRight}{\cardImageLeft+120mm}%
  \setlength{\cardImageTop}{\cardImageBottom+120mm}%
  \includegraphics[
    viewport={{\cardImageLeft} {\cardImageBottom} {\cardImageRight} {\cardImageTop}},
    clip,
  ]{\cardImagePath}%
  \addtocounter{cardImageNumber}{1}%
}

% place next three cards on one page
\newcommand*{\cardPage}{%
  \vspace*{\fill}%
  %
  \begin{tikzpicture}
    \node at (0,17) {\cardImage};
    \node at (8,8.5) {\cardImage};
    \node at (0,0) {\cardImage};
  \end{tikzpicture}%
  %
  \vspace*{\fill}%
  \pagebreak%
  \par%
}

\begin{document}

\cardPage
\cardPage
\cardPage
\cardPage
\cardPage
\cardPage
\cardPage
\cardPage
\cardPage
\cardPage
\cardPage

\end{document}