=======================================
GraphicsMagick Mercurial
=======================================

.. meta::
   :description: GraphicsMagick is a robust collection of tools and libraries to read,
                 write, and manipulate an image in any of the more popular
                 image formats including GIF, JPEG, PNG, PDF, and Photo CD.
                 With GraphicsMagick you can create GIFs dynamically making it
                 suitable for Web applications.  You can also resize, rotate,
                 sharpen, color reduce, or add special effects to an image and
                 save your completed work in the same or differing image format.

   :keywords: GraphicsMagick, Image Magick, Image Magic, PerlMagick, Perl Magick,
              Perl Magic, CineMagick, PixelMagick, Pixel Magic, WebMagick,
              Web Magic, visualization, image processing, software development,
              simulation, image, software, AniMagick, Animagic,  Magick++

.. _Mercurial : http://mercurial.selenic.com/
.. _TortoiseHg : http://tortoisehg.bitbucket.org/
.. _`GraphicsMagick Hg` : http://graphicsmagick.hg.sourceforge.net/hgweb/graphicsmagick/graphicsmagick/

.. contents::

The GraphicsMagick source code is now available via Mercurial_.
Previously GraphicsMagick source control was via CVS (which is still
working in a read-only mode), but now the repository has been migrated
to Mercurial_.  Mercurial_ is a convenient way for developers from
around the country or world to download the GraphicsMagick source, fix
bugs, or add new features.

What is Mercurial?
==================

Mercurial_ (also known as `Hg` due to the abbreviation for Mercury in
the periodic table of the elements) is a modern source control system
which provides anyone who clones a repository with a stand-alone local
repository containing the full development history and the ability to
select any version of the code.  Since the local repository is
fully-functional, you may use the same repository to manage your local
changes to GraphicsMagick code.

Web Access
=============

A `GraphicsMagick Hg`_ web interface is available which may be used to
interactively view the latest versions of files, or the changes to
files, using your web browser.  Due to the way that Mercurial_ works,
you may also clone a new repository from this interface via the same URL.

Cloning the Mercurial Repository
==================================

To get the tree and place it in a sub-directory of your current working
directory, issue the command::

  hg clone http://graphicsmagick.hg.sourceforge.net/hgweb/graphicsmagick/graphicsmagick/ GM

Selecting a version of the code
========================================

By default the cloned directory is populated with files from the
`default` (i.e. head) branch of the code.

If you require a specific release of GraphicsMagick (e.g. 1.3.9), you may select it like::

  hg update -r GraphicsMagick-1_3_9

or if you require a specific branch of GraphicsMagick (e.g. 1.3), you may use::

  hg update -r GraphicsMagick-1_3

or you may request the files which were current on a specific date::

  hg update -d 2009-01-14

Use::

  hg branches

to see the available branches, and::

  hg tags

to see the available release tags.

Updating from the Mercurial Repository
========================================

To pull more changes from the repository, execute::

  hg pull

and to make them visible in your files (via a merge), execute::

  hg update

or just::

  hg pull -u

The latter pulls down any updates into your local repository and
automatically does a merge.

Mercurial Software
==================

The best place to look for the latest version of Mercurial (`Hg`) is
at the Mercurial_ web site.  Most free operating systems (e.g. Linux,
OpenSolaris, and \*BSD) will offer a version of Mercurial as an
installable package and it may already be installed on your system.
We recommend use of TortoiseHg_ on Microsoft Windows systems since it
provides a very nice graphical interface.  TortoiseHg_ is also
available on Linux and other systems.

Mercurial for GraphicsMagick Developers
========================================

Since Mercurial_ is a distributed revision control system, you may
clone the GraphicsMagick repository and work for days or weeks (making
your own local commits) before you deside to push some or all of your
changes to the GraphicsMagick development repository.  GraphicsMagick
developers first commit changes to their own local respository, then
they push their changes to the GraphicsMagick development repository
at hg.graphicsmagick.org, later on (after testing and possible fixes)
I will push the changes to the stable repository at SourceForge.
Pushes to the stable repository at SourceForge should occur at least
as often as source code snapshots are produced.

The repository hierarchy is as follows:

1. Local

  The developer makes any local changes and commits he likes in his
  own repository.  It is best to commit often and whenever all the
  files have been updated to implement a coherent change or feature
  (including the ChangeLog file!) since Mercurial_ stores related
  changes as a changeset along with the change message you enter.
  When you push your repository, these changesets and messages are
  preserved.

2. Unstable

  The unstable development repository is available via ssh at
  "ssh://yourid@hg.GraphicsMagick.org//hg/GraphicsMagick".

  Where `yourid` is the Unix user ID on the GraphicsMagick server.
  The `yourid@` part may left out if your client system uses the same
  user ID as on the GraphicsMagick server.

3. Stable

  The stable repository is available via http at
  "http://graphicsmagick.hg.sourceforge.net/hgweb/graphicsmagick/graphicsmagick/".
  Any changes in the unstable development repository are pushed to
  the stable repository (by me) once any necessary adjustments have
  been made and the software test suite has passed.

To build your local development repository (as quickly as possible),
you may use these steps:

1. Clone the stable respository at SourceForge::

     hg clone http://graphicsmagick.hg.sourceforge.net/hgweb/graphicsmagick/graphicsmagick/ GM

2. Adjust your local repository path default to use the unstable repository.

   Edit .hg/hgrc in your local repository so that it contains::

     [paths]
     default = ssh://yourid@hg.GraphicsMagick.org//hg/GraphicsMagick

   where `yourid` is the Unix user ID on the GraphicsMagick server.

3. Pull any additional pending updates from the unstable repository::

     hg pull -u

Please note that when ssh access is used, Mercurial uncompresses any
data and sends it in uncompressed form.  Mercurial expects that
compression will be enabled in ssh when needed.  One way to enable ssh
compression is to put this in your local .hgrc::

  [ui]
  ssh = ssh -C

but ssh also provides its own way to enable compression on a
site-by-site basis (e.g. via .ssh/config).

Email Notifications
===================

.. _`graphicsmagick-commit` : https://lists.sourceforge.net/lists/listinfo/graphicsmagick-commit

An email notification is sent to the `graphicsmagick-commit`_ mailing
list at SourceForge whenever a change is submitted to the development
(unstable) repository.  Subscribe to this list if you would like to be
notified by email of changes when they occur.


--------------------------------------------------------------------------

.. |copy|   unicode:: U+000A9 .. COPYRIGHT SIGN

Copyright |copy| GraphicsMagick Group 2011
