% Style file for LaTeX2e
% For documentclass article
%   \documentclass [landscape]{article}  % optionally use portrait
%   \usepackage {slidepack}
%
% This package modifies the article class.  Paper sizes and orientation
% (portrait or landscape) are options to the article class.  This package
% uses the standard LaTeX2e color package, unless the nocolor option is
% specified.
%
% options:
%    frame (default) - place a frame around the slide.  The page style is set
%      to frame.
%    noframe  - do not place a frame around the slide.  The page style is not
%      altered and if not set otherwise remains the plain page style.
%    20pt - set the normal font size to be 20 pt.  This is also the default
%      and in this implementation) cannot be changed.
%    color (default) - load the standard LaTeX2e color package.  This option
%      loads the standard color package and sets the default frame color to
%      be a mid-gray level.
%    nocolor - do not load the color package.  The frame color is set to black.
%    <option> - any other options are passed to the color package
%
% page styles:
%    This package defines two new page styles, which correspond to empty and
%    plain, but with a frame around the page.  (The frame is part of the
%    header in these new page styles.)  
%    frame - place a frame around the page, include a page number - this is the
%      page style chosen if the (default) frame option to this package is
%      chosen.
%    framenn - place a frame around the page, do not include a page number
%
% dimensions:
%    The following dimensions can be reset to override default values.
%    After defining the dimensions, a recalculation of the text size and the
%    frame position can be initiated by invoking the \setslidesize macro.
%    Note that the frame is treated as being of zero thickness for calculating
%    the text positions.
%    \htextborder - offset between the sides of the frame and the text on the
%         left and right sides (default 0.6in)
%    \ttextborder - offset between the top of the frame and the top of the text
%         (header line) (default 0.5in)
%    \btextborder - offset between the bottom of the frame and the bottom of
%         the text (footer line) (default 0.2in)
%    \hframeoffset - space between the frame and the left and right edges of
%         the paper (default 0.6in)
%    \vframeoffset - space between the frame and the top and bottom edges of
%         the paper (default 0.6in)
%    \framethickness - thickness of the frame (default 0.05in)
%    \headheight - height of the header (default 0pt)
%    \headsep - separation between the header and the main text area (default
%         0pt)
%    \footskip - distance from the bottom of the main text area to the bottom
%         of the footer (default 0.4in)
%    \topmargin, \textwidth, \textheight - these values are calculated from
%         the parameters above and the paper size
%    \vannotoffset - distance above or below the frame to the annotation
%         (default 0.1in)
%    \hannotoffset - distance from the left edge of the frame to the annotation
%         (default 0.2in)
%
% macros:
%    The following macros can be defined by the user to override default
%    definitions.
%    \framecolor - color command for the frame, initially "color{midgray}"
%         where midgray is defined as \definecolor{midgray}{gray}{0.6}.
%    \annotation[where]{text} - this macro places text at the left above the
%         frame (for where=t) or at the left below the frame (for where=b, also
%         the default)
%    \setslidesize - causes a recalculation of the text size and frame
%         position.  This macro should be invoked if the dimensions affecting
%         the text size or frame position are changed.
%
% Notes:
%  - invoke this package immediately after invoking the article class so that
%    the correct font size is in effect for subsequent packages
%  - consider setting \parindent=0pt
%  - consider using \raggedright, especially for portrait mode slides which
%    have relatively short lines
%  - the \maketitle macro invokes \thispagestyle{plain}, effectively removing
%    frame for the first page.  Invoke \thispagestyle{framenn} or
%    \thispagestyle{frame} to override this setting.
%  - figures can be obstinate, they will often move to the next page.  Try
%    using \begin{figure}[!h] to get LaTeX to try harder to put the figure
%    on the current page.
%
% Example:
% \documentclass [landscape]{article}
% \usepackage {slidepack}
% \usepackage {exscale}		% To use large size math symbols
%
% \annotation[t]{{\upshape PK } Examples}
%
% \begin{document}
%
% \title{My Slide Presentation\\
%	 for all to see}
% \author{Peter Kabal}
%
% \maketitle
% \thispagestyle{framenn}	% override plain page style set by \maketitle
% \newpage
%
% \subsection*{Overview of the Slide Presentation}
%
% This slide contains the overview of the slide presentation.
% \begin{itemize}
% \item Overview
%    \begin{itemize}
%      \item title slide
%      \item overview slide
%    \end{itemize}
% \item Equation Page
% \end{itemize}
%
% \newpage
% \subsection*{Equations:}
%
% \[
%   A_n(z) = A_{n{-}1}(z) - k_n z^{-n} A_{n{-}1}(z^{-1})
% \]
%
% \end{document}

% $Id: slidepack.sty,v 1.17 1997/09/14 00:55:18 kabal Exp $

\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{slidepack}[1995/12/02]

%================== options
\newif\if@frame
\newif\if@color
\newif\if@landscape
\newcommand\pt@size{}

\DeclareOption{frame}{\@frametrue}
\DeclareOption{noframe}{\@framefalse}
\DeclareOption{landscape}{\@landscapetrue}
\DeclareOption{20pt}{\renewcommand\@ptsize{x}\renewcommand\pt@size{20}}
\DeclareOption{color}{\@colortrue}
\DeclareOption{nocolor}{\@colorfalse}
\DeclareOption*{\PassOptionsToPackage{\CurrentOption}{color}}

\ExecuteOptions{frame,20pt,color}
\ProcessOptions

\input{size\pt@size.clo}

% This package overrides the font sizes defined by the article class.  The
% font size settings are invoked early in article.cls by calling a class
% option file (size10.clo for instance).  The article class has provision only
% for font sizes 10pt, 11pt and 12pt.  The 20 pt size option to this package
% should really be an option to the article class so size.  This requires
% (minimally) modifying the file article.cls to have it invoke size20.clo.

% article.cls changes with releases of LaTeX2e, such that a particular release
% of article.cls may not be compatible with another release of LaTeX2e.  To
% avoid the hassle of having a separate customized version of article.cls for
% each revision of LaTeX2e, this package invokes the article class with the
% default font size (10pt).  It then resets the font size using size20.clo.
% This works fine except that the list item indentation dimensions which are
% set directly in article.cls (rather than the size??.clo file) depend on the
% the font sizes in effect at the time.  Here we have to set those dimensions
% again according to the current font size.  (This does not apply to macros
% defined in article.cls that use font related dimensions as the macro will
% pick up the correct values when invoked.)
% ===== article.cls =====
\if@twocolumn
  \setlength\leftmargini  {2em}
\else
  \setlength\leftmargini  {2.5em}
\fi
\setlength\leftmarginii  {2.2em}
\setlength\leftmarginiii {1.87em}
\setlength\leftmarginiv  {1.7em}
\if@twocolumn
  \setlength\leftmarginv  {.5em}
  \setlength\leftmarginvi {.5em}
\else
  \setlength\leftmarginv  {1em}
  \setlength\leftmarginvi {1em}
\fi
\setlength\leftmargin    {\leftmargini}
\setlength  \labelsep  {.5em}
\setlength  \labelwidth{\leftmargini}
\addtolength\labelwidth{-\labelsep}
% ===== ... =====
\bibindent=1.5em
% =====

\if@color
  \RequirePackage{color}
\fi
\RequirePackage{exscale}	% Enable big math symbols

% Set dvips to landscape orientation (if the color/graphics package is loaded)
% Note that \paperheight and \paperwidth have already been swapped in the
% processing of the article class)
% e.g. \paperwidth=8.5in \paperheight=11in after landscape article option
%      become \paperwidth=11in and \paperheight 8.5in
% Set dvips to rotate clockwise rather than counterclockwise for landscape.
% This orientation avoids the upside down rendition in ghostview.
\if@landscape
  \def\t@name {dvips.def}
  \ifx \Gin@driver\t@name
    \special {papersize=\the\paperwidth,\the\paperheight}
    \special {! /landplus90 true store}
  \fi
\fi

%================== page layout
% Page layout:
%   (1) The frame is centered horizontally and vertically on the page
%   (2) The text is centered horizontally within the frame (\htextborder at
%       either side)
%   (3) The text (from the header to the footer) has \ttextborder at the top
%       and \btextborder at the bottom
\newdimen\htextborder
\newdimen\ttextborder
\newdimen\btextborder
\newdimen\framethickness
\newdimen\hframeoffset
\newdimen\vframeoffset

\newdimen\framewidth
\newdimen\frameheight

\newdimen\hannotoffset
\newdimen\vannotoffset

\newdimen\oddsideframeshift
\newdimen\evensideframeshift
\newdimen\topframeshift

\htextborder=0.6in
\ttextborder=0.5in
\btextborder=0.2in 	% Page number comes close to the frame
\hframeoffset=0.6in	% Offset to center of frame line
\vframeoffset=0.6in
\framethickness=0.05in

\headheight = 0pt
\headsep = 0pt
\footskip = 0.4in

\hannotoffset = 0.2in
\vannotoffset = 0.1in

\def\setslidesize{%

% Text parameters
  \textwidth = \paperwidth
    \advance\textwidth by -2\hframeoffset
    \advance\textwidth by -2\htextborder
  \oddsidemargin = \hframeoffset
    \advance\oddsidemargin by \htextborder
    \advance\oddsidemargin by -1in
  \evensidemargin = \oddsidemargin
  \textheight = \paperheight
    \advance\textheight by -2\vframeoffset
    \advance\textheight by -\ttextborder
    \advance\textheight by -\btextborder
    \advance\textheight by -\headheight
    \advance\textheight by -\headsep
    \advance\textheight by -\footskip
  \topmargin = \vframeoffset
    \advance\topmargin by \ttextborder
    \advance\topmargin by -1in

% Frame parameters
  \framewidth=\paperwidth
    \advance\framewidth by -2\hframeoffset
  \frameheight=\paperheight
    \advance\frameheight by -2\vframeoffset
  \oddsideframeshift = \hframeoffset
    \advance\oddsideframeshift by -\oddsidemargin
    \advance\oddsideframeshift by -1in
  \evensideframeshift = \hframeoffset
    \advance\evensideframeshift by -\evensidemargin
    \advance\evensideframeshift by -1in
  \topframeshift = \vframeoffset
    \advance\topframeshift by -0.5\headheight
    \advance\topframeshift by -\topmargin
    \advance\topframeshift by -1in
}

% Set the parameters
\setslidesize

%================== annotations
\providecommand\bannotation{}
\providecommand\tannotation{}
\providecommand\annotfont{\reset@font\itshape\small}
\newcommand\annotation[2][b]{%
  \ifx #1b%
    \def\bannotation{\annotfont #2}%
  \else
    \ifx #1t%
      \def\tannotation{\annotfont #2}%
    \else
      \PackageWarning{slidepack}{Invalid optional argument: "#1"}%
    \fi
  \fi}
\def\tannotbox{\vbox to 0pt{%
                    \vss
                    \hbox to 0pt{%
                         \hskip \hannotoffset
                         \tannotation
                         \hss}%
                    \vskip \vannotoffset
                    }}
\def\bannotbox{\vbox to 0pt{%
                    \vskip \vannotoffset
                    \hbox to 0pt{%
                         \hskip \hannotoffset
                         \bannotation
                         \hss}%
                    \vss
                    }}

%================== slide frame
\def\hbrule{\vbox {\vskip -0.5\framethickness
                   \hbox {\advance\framewidth by \framethickness	% local
                          \hskip -0.5\framethickness
                          \vrule width \framewidth
                                 height \framethickness
                                 depth 0pt
                          \hskip -0.5\framethickness}%
                   \vskip -0.5\framethickness}}
\def\vbrule{\hbox {\hskip -0.5\framethickness
                   \vbox {\advance\frameheight by \framethickness	% local
                          \vskip -0.5\framethickness
                          \hrule width \framethickness
                                 height \frameheight
                                 depth 0pt
                          \vskip -0.5\framethickness}%
                   \hskip -0.5\framethickness}}

% The slide frame appears to the right of and below the current point.
% The slide frame also extends to the left and above by a half frame line
% thickness.
\if@color
  \definecolor{midgray}{gray}{0.6}
  \def\framecolor{\color{midgray}}
\else
  \def\framecolor{}
\fi
\def\slideframe#1#2{\hbox to 0pt{%
                        \hskip #1
                        \vbox to 0pt{%
                            \vskip #2
                            \tannotbox
                            {\framecolor	% group to keep colour local
                             \hbrule
                             \hbox {\vbrule
                                    \hbrule
                                    \vbrule}}%
                            \bannotbox
                            \vss
                            }%
                        \hss}}

%================== define a frame and framenn (no number) pagestyle
% Similar to \ps@plain
\def\ps@frame{%
  \ps@plain
  \def\@oddhead{\slideframe{\oddsideframeshift}{\topframeshift}\hfil}%
  \def\@evenhead{\slideframe{\evensideframeshift}{\topframeshift}\hfil}}
\def\ps@framenn{%
  \ps@empty
  \def\@oddhead{\slideframe{\oddsideframeshift}{\topframeshift}\hfil}%
  \def\@evenhead{\slideframe{\evensideframeshift}{\topframeshift}\hfil}}

% Use the frame pagestyle if the frame option has been selected
\if@frame
  \pagestyle{frame}
\fi