\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{folien}[2000/11/28
   v0.0 (c) IKS Garamond -- Lutz Donnerhacke]

\usepackage{ifthen,url}

\raggedright

\newbox\lbildbox\newbox\rbildbox
\AtBeginDocument{%
   \setbox\lbildbox\hbox{\leftbild}%
   \setbox\rbildbox\hbox{\rightbild}%
}

\newcommand*{\kopf}[2][print]{\mbox{}%
  {\ifthenelse{\equal{print}{#1}}%
    {\visible\usebox\lbildbox}%
    {\invisible\vbox to\ht\lbildbox{\hbox{x}}}}%
  \hfill\thema\hfill
  {\ifthenelse{\equal{print}{#1}}%
    {\visible\usebox\rbildbox}%
    {\invisible\vbox to\ht\rbildbox{\hbox{x}}}}%
  \mbox{}%
  \par\hrule\par
  }

\newenvironment*{my}%
  {\begin{slide}\kopf{\theslide}}%
  {\vfill\end{slide}}

\newenvironment*{myo}%
  {\begin{overlay}\kopf[noprint]{}}%
  {\vfill\end{overlay}}

\newcounter{overlaycount}[slide]
\newcounter{maxoverlay}[slide]
\newcommand*{\myoverlay}[2]{%
  \ifthenelse{\value{overlaycount} = 0}{%
    \ifthenelse{\value{maxoverlay} < #1}{%
      \setcounter{maxoverlay}{#1}%
    }{}%
  }{}%
  {\ifthenelse{\value{overlaycount} = #1}\visible\invisible #2}%
}

\long\def\multislide#1#2#3{
  \begin{#1}
      #3
  \end{#1}
  \whiledo{\value{overlaycount} < \value{maxoverlay}}{
    \stepcounter{overlaycount}
    \begin{#2}
	\invisible #3
    \end{#2}
    }
  }

\newcommand{\section}[1]{{\Large #1}}
\newcommand{\subsection}[1]{{\large #1}}
\newenvironment{si}{\begin{itemize}\setlength{\itemsep}{0pt}}{\end{itemize}}
\newenvironment{sd}{\begin{description}\setlength{\itemsep}{0pt}}{\end{description}}
\newenvironment{vb}{\tiny
  \ttfamily
  \obeylines\obeyspaces
  \parskip0pt%
  \parindent0pt%
  }{}


\newcommand{\hence}{$\Rightarrow$~}
\newcommand{\rurl}[1]{\vspace{\baselineskip}\rightline{\tiny\url{#1}}}