-*-text-*- $Id: README,v 3.3 1996/12/19 03:31:56 krisrose Exp $

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	THE Xy-pic PACKAGE FOR TYPESETTING GRAPHS AND DIAGRAMS
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Xy-pic is a package for typesetting graphs and diagrams with TeX.

It works with most formats, including LaTeX (both 2.09 and 2e),
AMS-LaTeX, AMS-TeX, and plain TeX.

It has been used to typeset complicated diagrams from many application
areas including category theory, automata theory, algebra, neural
networks, and database theory.

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See below in this file for an overview of the structure and features!
See CATALOG for up to date version information!
See TRAILER for author and accessibility information!
See COPYING for the conditions for redistribution and modification!
See MANIFEST for a complete file list!
See VERSIONS for the exact list of the versions of all source files!
See the various INSTALL files for how to install Xy-pic on your system!
See the W3 <URL: http://www.diku.dk/~kris/Xy-pic.html> for news!

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Xy-pic is structured as a `kernel' and several orthogonal modules called
`options', each defining a custom notation for a particular kind of
graphical object or structure.

These (combinable) structures are available:

* A graph combinator mode where diagrams are specified the way they are
  composed as graphs.

* A matrix-like mode where the dimensions of the drawing are computed by
  aligning diagram entries in rows and columns (this is the `diagram'
  mode Xy-pic version 2 users are used to).

* A polygon mode where diagrams shaped as regular polygons are entered
  in a simple way.

* A mode for typesetting beautiful knots and links.

* A general object-oriented `turtle graphic' drawing language for
  specifying graphs with objects and connections between them in a
  manner independent of orientation.

The following objects may be used:

+ Positions can be given in variety of formats (extendable) including
  user defined coordinates (x,y) and relative to previous positions,
  objects, object edges, and points on connections.

+ Objects may be circular, elliptic, or rectangular (more shapes can be
  added) and adjusted in several ways.

+ Large library of objects with mnemonic names.

+ Objects that orient themself along a connection when placed relative
  to it, e.g., `\dir{|-}' is like \vdash but thus oriented; new such
  objects can be defined in a convenient way.

+ TeX `boxes', i.e., text and mathematical formulae.

+ Includes circle segments and optionally arbitrary elliptical,
  quadratic, and cubic arcs.

+ Connections are aligned between the reference points of objects but
  start and end on the edges.

+ Any object can be used to build a connection (using `diagonal
  filling'); library objects provide common line types.

+ Flexible notation for drawing arrows and general paths with tail,
  stem, and head built from any object(s).  Special support for arrows
  that cross each other, arrows that `go by' other entries, paired
  arrows (including support for 2-cells), curved arrows, and arrows with
  bends.

+ Library of frames and braces.

+ Special notation for rotation, scaling, colour, and line thickness.
  The correct typesetting of these features requires a backend that
  supports it (i.e., PostScript) but even when this is not available
  Xy-pic tries to approximate what is requested such that at least the
  picture size is stable (and thus page breaks).

+ Output can use PostScript for drawing (several \special formats are
  supported: dvips, Textures, and OzTeX -- more are being added
  continuously: contact Ross Moore <[email protected]> for the current
  list).  Notation for inclusion of literal PostScript is available.

* Other graphics can be imported and then `decorated' using Xy-pic.

All object forms may be used with all structures.

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Finally, enjoy Xy-pic!

Sincerely,
		Kristoffer H. Rose	<[email protected]>
		Ross Moore		<[email protected]>