%%
% File: cjwresize.sty
%%

\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{cjwresize}
    [1995/05/09 v0.1  Change Default LaTeX Page Layouts -- CJW]

\newif \if@autocalc

\DeclareOption{auto}{\@autocalctrue}
\DeclareOption*{%
  \PackageWarning{cjwresize}{Unknown option `\CurrentOption'}}

\ProcessOptions

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% DISTRIBUTION NOTICE
%
%   This is file |cjwresize.sty| for use with \LaTeX2e.
%
%   Copyright (c) 1995 by Colin J. Wynne
%         cwynne@sage.wlu.edu, cwynne@lorien,princeton.edu,
%                     ua7o@rz.uni-karlsruhe.de
%   This file may be freely distributed in any form; electronic,
%   physical or otherwise; so long as the distributor provides this
%   file in its entirety (including this message) and the distributor
%   receives no money (except for a reasonable recompense for the
%   duplication process).  Fair 'nough?
%
%   This file is beer-ware.  If you use it and like it, then you
%   should buy me a beer if you ever meet me. :-)
%
%
% INTRO
%
%   This is a fairly simple file, so I am not going to bother with a
%   .dtx file.  Here is the whole documentation, right here. :-)  No
%   \docstrip{} hastle or anything...
%
%
% WHY THIS PACKAGE?
%
%   I think the default printable area used by \LaTeX{}, frankly,
%   sucks.  When I turn in three problem assignments for a math class
%   and it takes up eight pages, there is just too much blank space.
%   So, I hacked the relevant parts out of |classes.dtx| which deal
%   with setting printable area and balancing margins and fiddled with
%   some of the default values.  Not only that, but it is easily
%   customisable.
%
%
% HOW TO USE THIS PACKAGE
%
%   There are two basic ways to use this package.  Essentially, after
%   including the package, the macro |\resize| is available to the
%   user.  After altering any of the relevant page information, one
%   can invoke |\resize| to recalculate page margins.  |\resize|
%   should be called after changes to the following:
%
%       \textheight        \headheight        \footskip
%       \textwidth         \headsep
%
%   and optionally after changing |\topskip|.  These are the
%   dimensions on which the \LaTeX{} algorithms below depend.
%
%   This only half solves the problem, though.  Having to change the
%   height and width in every document is also not a particularly
%   ducky solution, so there is also a package option, namely |auto|.
%   In commented sections below, you will see where I have altered
%   some of the default values that \LaTeX{} uses for page layout
%   calculations.  Invoking the package with the |auto| option will
%   automatically do a resize with these defaults.  Of course, the
%   |\resize| command will still be available if further modifications 
%   are desired.  You should feel perfectly free to change these
%   defaults to something that will be more appropriate for you.
%
%
% BUGS
%
%   Well, I wouldn't call this a bug, but I haven't accounted for the
%   slight differences in these calculations specific to the |book|
%   class's options for size switching.  This package was written in
%   about twenty minutes, and I couldn't think of a way off the type
%   of my head to test for the invoked class.  If there is one (and
%   I'm fairly sure there is), please let me know.
%
%
% COMMENTS?
%
%   If you have any, send them to me at one of the e-mail addresses
%   above.  I hope this will be useful to somebody, somewhere.
%
%                                         CJW, 09.05.1995
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\def\resize{\relax%
      %
  \if@twoside
    \setlength\@tempdima        {\paperwidth}
    \addtolength\@tempdima      {-\textwidth}
    \setlength\oddsidemargin    {.4\@tempdima}
    \addtolength\oddsidemargin  {-1in}
      %
    \setlength\marginparwidth   {.6\@tempdima}
    \addtolength\marginparwidth {-0.4in}
  \else
    \setlength\@tempdima        {\paperwidth}
    \addtolength\@tempdima      {-\textwidth}
    \setlength\oddsidemargin    {.5\@tempdima}
    \addtolength\oddsidemargin  {-1in}
    \setlength\marginparwidth   {.5\@tempdima}
    \addtolength\marginparwidth {-.4in}
  \fi
      %
  \ifdim \marginparwidth >2in
    \setlength\marginparwidth{2in}
  \fi
      %
  \@settopoint\oddsidemargin
  \@settopoint\marginparwidth
      %
  \setlength\evensidemargin  {\paperwidth}
  \addtolength\evensidemargin{-2in}
  \addtolength\evensidemargin{-\textwidth}
  \addtolength\evensidemargin{-\oddsidemargin}
      %
  \@settopoint\evensidemargin
      %
      %
  \setlength\topmargin{\paperheight}
    \addtolength\topmargin{-2in}
    \addtolength\topmargin{-\headheight}
    \addtolength\topmargin{-\headsep}
    \addtolength\topmargin{-\textheight}
    \addtolength\topmargin{-\footskip}
      %
  \addtolength\topmargin{-.5\topmargin}
  \@settopoint\topmargin
}

%%%%
%%%%
%%
%% CODE for the |auto| option:
%%
%%%%
%%%%

\if@autocalc

%%
% Compute the |\textwidth|.
%%

  \setlength\@tempdima{\paperwidth}
  \addtolength\@tempdima{-2in}

%%
% This choice of |\@tempdimb| is the `default' page size used by the
% |auto| option.  The values from |classes.dtx| are 345pt, 360pt and
% 390pt respectively for 10pt, 11pt and 12pt document sizes.  Feel
% free to change these to taste.  I find that adding about 40--50pt to
% the original dimensions works pretty well.
%%
  \ifcase \@ptsize
    \setlength\@tempdimb{385\p@} \or
    \setlength\@tempdimb{400\p@} \else
    \setlength\@tempdimb{430\p@}
  \fi

  \if@twocolumn
    \ifdim\@tempdima>2\@tempdimb\relax
      \setlength\textwidth{2\@tempdimb}
    \else
      \setlength\textwidth{\@tempdima}
    \fi
  \else
    \ifdim\@tempdima>\@tempdimb\relax
      \setlength\textwidth{\@tempdimb}
    \else
      \setlength\textwidth{\@tempdima}
    \fi
  \fi

  \@settopoint\textwidth

%%
% Compute the |\textheight|.
%%

  \setlength\@tempdima{\paperheight}
%%
% These next two lines govern the `default' |\textheight| used by the
% |auto| option.  The values from |classes.dtx| are -2in for the
% margins and -1.5in for headers and footers.  I like reducing the
% extra space for headers/footers down to -1in.  Feel free, however,
% to change these values to taste.
%%						%%
    \addtolength\@tempdima{-2in}		% Minimum margins.
    \addtolength\@tempdima{-1in}		% Room for head/foot stuff.
						%	  
  \divide\@tempdima\baselineskip		% Compute size in 
    \@tempcnta=\@tempdima			% line numbers.
  						%
  \setlength\textheight{\@tempcnta\baselineskip}%
    \addtolength\textheight{\topskip}		% First line of text has
				   		% height |\topskip|.
%%						%%
% Now call resize.
%%
  \resize

\fi

\endinput
%%
% End of file: cjwresize.sty
%%