prerex, version 6.0.3: Macros for prerequisite charts, with associated
editor and viewer applications. 

This package consists of 

  prerex.sty 
    a LaTeX package for producing charts of course nodes
    linked by arrows representing pre- and co-requisites,

  prerex 
    an interactive program for creating and editing chart
    descriptions, and

  vprerex ("visual prerex", formerly called "previewer") 
    a GUI and previewer for prerex.

The implementation of prerex.sty is built on pgf, so that it may
be used equally happily with latex or pdflatex; prerex is written in C
and vprerex is written in C++ using the Qt-4 toolkit and the poppler
library.

See chart.{pdf,html} for a small example of a prerequisite chart and
real-life examples at

http://www.cs.queensu.ca/students/undergraduate/prerequisites/

Prerequisite charts are useful to students selecting courses and
planning their programs, and to faculty and staff advising students
and managing curriculum development. Conventional sources of course,
program and timetable information are rarely in a user-friendly format.
Faculty and staff advisors, being already fairly familiar with their
courses and programs, often do not appreciate how inconvenient it is
for students to access all the information they need to make course
choices. 

The crucial tool in the prerex suite is "prerex.sty", a macro package
that defines a "chart" environment and commands to specify construction
of course boxes and directed arrows between them.

prerex.sty depends on

  pgf (and add-on tikz), version 1.18 or higher 
  multido
  relsize
  calc
  ifthen
  zref-savepos
  hyperref

The use of pgf means that Postscript processing is not required;
either pdflatex or latex -> dvips [ -> ps2pdf ] may be used.

Installation of prerex.sty:

  + copy prerex.sty to your-texmf-tree/tex/latex/misc
  + copy doc/prerex.{tex,pdf} to your-texmf-tree/doc/latex/misc
  + if necessary, refresh the TeX database (e.g., texhash)
  + copy doc/prerex.sty.7 to sub-directory man7 of a man directory on your 
    MANPATH
  + test by doing 

       man 7 prerex.sty
       pdflatex chart.tex

See doc/prerex.pdf for detailed documentation.

The prerex editor allows interactive editing of the chart environments
of LaTeX source files. It supports add, remove, cut-and-paste, and edit
operations on course boxes and arrows, and vertical or horizontal shifts
of the whole diagram or selected sets of course boxes. When a course
box is moved, the arrows into and out of it automatically follow. 
To install:

  tar zxvf prerex-6.0.3.tar.gz
  cd prerex-6.0.3
  ./configure --help
  ./configure [options]
  make
  sudo make install

The effects of editing operations may be observed in any PDF viewer.
The vprerex (visual prerex) application included in the prerex suite
is a GUI and viewer for the prerex editor. It may be used just as a
minimalistic viewer of arbitrary PDF files but supports editing of
charts generated using prerex.sty by allowing coordinates of course
boxes, arrows, and background points to be conveyed back to the prerex
editor command-line using the clipboard.

See the INSTALL in the tarball for installation instructions.

An alternative is to use a version of kpdf/okular (PDF viewers in KDE)
that has been patched to provide the same access to chart coordinates.
The "patches" sub-directory provides patches for several recent
versions of kpdf (KDE-3) and okular (KDE-4). See patches/README for
instructions.

See the file doc/intro.pdf for an overview of the prerex system.

prerex.sty, README.prerex, prerex.1, prerex.5, prerex.sty.7, prerex.tex
and chart.tex may be modified and distributed according to the terms of
the LaTeX Project Public License.

The source files for prerex, vprerex, and the kpdf/okular patches may
be modified and distributed according to the terms of the GNU General
Public Licence (version 2).