review_process_rules.html

---
layout: page
title: Contributing to CGAL
header: Contributing to CGAL
group: navigation
---
{% include JB/setup %}

<h1>Submission, Review, and Integration</h1>

<p>On this page we describe the process for integrating a new feature into
the CGAL library. A feature is a clearly delimited piece of functionality
that is described by
</p>
<ul>
<li> its motivation, purpose, and intended use (user manual), and </li>
<li> its API in C++ (reference manual).</li>
</ul>
<p>Features may range from small (one new function, for example)
up to large (a complex hierarchy of classes). Features may extend
  existing CGAL packages or form new packages.
</p><p id="mustbe">In order for a feature to become part of CGAL, it must be
submitted to the Editorial Board of CGAL first <a href="#small_submissions">(*)</a>.

<br>Subsequently, the submitted feature is reviewed by the Editorial
Board (possibly with the help of external reviewers). Based on the
reviews and subsequent discussions with the authors, the Editorial
Board may reject the feature, or invite it to pursue the process after
major or minor modifications. A feature whose authors have
satisfactorily addressed all the requested modifications is invited to
the integration process. This step extensively tests its
functionality, cross-platform behavior, and interaction with other
parts of the library. Once the tests are successful and the feature is
stable, it is scheduled for release.
</p>

<ul>
  <li><a href="#Submission">Submission</a>
  <ul>
    <li><a href="#Registration">Registration</a></li>
    <li><a href="#Formal_Submission">Formal Submission</a></li>
  </ul>
  </li>
  <li><a href="#Review">Review</a></li>
  <li><a href="#Integration">Integration</a></li>
</ul>

<h3 id="Submission"> Submission  </h3>
<p>This is a two-stage process. The authors of a new feature first need
to register it by providing a minimum amount of (mostly non-technical)
information. This first stage allows the Editorial Board to check
whether the intended feature is suitable for CGAL at all. The goal
here is to avoid that the considerable effort of a formal submission
(second stage) is wasted on out-of-scope features.
</p>

<h4 id= "Registration"> Registration</h4>
<p>In order to register a feature, the corresponding author should send
an email to the <a href="./people.html">Editorial Board</a>, using the address <b>info AT
cgal.org</b>. Within this email (or on a website that you
linked to from the email), the following information must be provided.
</p>

<ul>
<li> <b>Summary of the feature</b>: what is its motivation, purpose,
    and intended use? Which algorithmic and geometric tools does it
    use and/or implement?
<br>This information allows the Editorial Board to check whether the
functionality implemented by the feature is suitable for CGAL.
</li>
<li> <b>Authors and maintainers of the feature.</b>
<br>In many cases, authors are already CGAL developers, but we also
welcome external contributions. In both cases, we need to know who is
going to maintain the feature in the future.
</li>
<li> <b>Intended license of the feature</b>.
<br>The feature's license should be compatible with the
<a href="./license.html">CGAL open source
licenses</a> (LGPL or GPL). If the feature deviates from this, the
reasons should be explained.
</li>
<li> <b>Intended copyright owner of the feature</b>.
<br>By default, the copyright on the code is owned by the employer of
  the author(s). If the feature is an extension of an existing
  package, a potential transfer or sharing of copyright will be
  debated. Typically, this process involves reaching an agreement
  between the legal departments of both the author's employer and of
  the institute(s) that own(s) the copyright of the package(s).
</li>
<li> <b>State of the feature</b>.
<br>Is it already fully implemented (even in CGAL?), is there a
prototype available, or is it in the design phase?  Usually, a
submission makes sense only if at least a prototype is available
already.
</li>
</ul>

<p>The Review Manager acknowledges the registration. (S)he
informs the corresponding author (usually within two weeks) by email
whether the feature is invited for a formal submission. In case a
feature is not invited, the decision will be explained to the
authors. The decision process might involve further discussions with
the authors.
</p>

<h4 id="Formal_Submission"> Formal Submission</h4>
<p>The formal submission consists of
</p>
<ul>
  <li> a user manual and a reference manual,
    <br>preferably in CGAL manual style, or similar. CGAL developers
      have access to the CGAL manual tools used to create CGAL manuals. For
      external contributions, access to the manual tools can be granted upon
      request.</li>
  <li> a proposal for integration into the manual,
      <br>ie: will it be inserted into an existing chapter? or will it
	form a separate chapter? in an existing part, or should a new
	part be created?
	<br>This proposal should be sent in a separate mail (or in the
	CGAL wiki, for authors who already have an access).
    </li>
</ul>
<p>The user manual contains the motivation, purpose, and intended
use of the feature, as well as examples and pictures, and
implementation details (which algorithm has been implemented? What is
its runtime?). The reference manual contains the precise API of the
feature, meaning its concepts, classes, and functions.
</p><p>The formal submission does not involve source code, and its
review is based purely on the user and reference manual. Source code
will be looked at during the integration phase.
</p>
<p>Authors whose feature has been invited should send the formal
submission to the Editorial Board of CGAL, again under <b>info AT
cgal.org</b>. The Review Manager acknowledges the formal
submission and gets back to the corresponding author (usually within
six weeks) with the initial reviews.
</p>

<p><a name="small_submissions">(*) </a><b><a href="#mustbe">^</a></b>
  The only exception to these submission
  rules are for very small features (typically a slight modification
  in the specifications, like a new function) in an existing package,
  done by its maintainers. The maintainers of a package can perform
  such small changes under their own responsibility. However, such
  changes must still be announced using the wiki page dedicated to
  this case. Then the Editorial Board may ask for a review or
  object.
</p>

<h3 id="Review"> Review </h3>

<p>The review process is initiated by the Review Manager who appoints
a primary reviewer for the feature. The primary reviewer is a member
of the Editorial Board and responsible for communication with the
authors. Besides his/her own review, the primary reviewer organizes at
least a secondary review. Initial reviews are neither anonymous nor
final; they are expected to be followed by a discussion between
authors on the one hand and the reviewers on the other
hand, with the goal of efficiently sorting out the critical
issues. The whole review process is documented on an appropriate wiki
page that is accessible to authors, reviewers, and all CGAL
developers.
</p><p>The time frame for the discussion period following the initial
reviews is flexible. The Review Manager makes sure that the primary
reviewer remains responsive throughout the discussion. It is in the
interest of the authors of the feature to remain responsive as well.
</p>

<p>When the discussion has stabilized, the primary reviewer proposes a
decision (the API is accepted or rejected) to the Editorial Board,
accompanying the proposal with the main arguments supporting it. The
final decision is made accordingly unless there is an objection by an
editor within fifteen days. 
</p><p>Reasons for rejection may be insurmountable dissensions between
authors and reviewers, or irresponsiveness on the side of the
authors. The Review Manager will inform the corresponding author
about the decision and explain it. In case of major modifications
being requested, a second round of reviews may become necessary.
</p>

<p>A feature whose API (Reference Manual) has been accepted is called
a <b>candidate</b> feature.
 The authors of a candidate feature are expected to become CGAL
  developers, in order to access the CGAL source code management system.
  From this point, they must maintain their
  code within CGAL's source code management system in a dedicated
  branch referred to as a "feature branch" (aka "topic branch").
  Once the feature branch is available, the authors are invited by
  the Release Manager to integrate their code in the testing process.
</p>

<p>Every CGAL release has a <b>Feature Freeze</b> date.

<br>The Feature Freeze, which is three months before the actual release
date, marks the date from which on the API of the library for the next
release is fixed/frozen, in particular, the reference manual should
not change after that date. Exceptions are obvious bug/typo fixes and
precisions in the specification.
<br>
Authors of a feature should take into account that it can take several
weeks until the first review arrives, which is usually followed by a
discussion with the author on issues raised by the review. Moreover,
changes need to be incorporated in a revised submission.
</p>
<p>A feature can be candidate for integration into a CGAL release only
if the authors have done all modifications to the reference manual
requested during the review process, and that these modifications have
again been checked by the reviewers, before the Feature Freeze of the next
release.
</p>

<center><img SRC="images/release_cycle_git.png" alt=""></center>

<h3 id="Integration"> Integration </h3>

<p>Before a package can actually be integrated in a CGAL release, some
more steps must be followed. We just sketch these steps in the current document:
</p>
<ul>
<li>The final version of the User Manual must be approved by the reviewers.
<li>The package must be accompanied by a full test-suite, and the
test-suite must run without errors.
</ul>

<p>Every CGAL release has a <b>Code Freeze</b> date.

<br>The Code Freeze, which is one month before the actual release
date, marks the date from which on the code should not change anymore
without explicit agreement of the release manager,
in order to not disturb the final preparation of the release.

</p>
<p>The authors of a feature which has gone through the whole process
successfully, before the Code Freeze, are invited by the Release
Manager to merge the feature branch into the main development branch
(the "next" branch).