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<p>The Graphiti project is a proposed open source project under the
proposed GMP container project within the <a
Modeling Project (EMP) Top-Level Project</a>.</p>
<p>This proposal is in the Project Proposal Phase (as defined in the
Eclipse Development Process) and is written to declare its intent and
scope. We solicit additional participation and input from the Eclipse
community. Please send all feedback to the <a href="">Eclipse Modeling</a>
Eclipse provides a modeling infrastructure evolving around the Eclipse
Modeling Framework (EMF). Offering graphical representations and editing
possibilities is an essential part of EMF. SAP has built and plans to
contribute an Eclipse-based graphics framework to enable easy
development of state-of-the-art diagram editors for domain models. SAP
plans to contribute the developed framework under the name Graphiti.
<p>The proposal of this new project needs to be aligned with
introducing a new umbrella project hosting the graphical modeling
framework <a href="">GMF</a> and
Graphiti as proposed in the Bugzilla bug report <a
The name of this new umbrella project will be GMP; it will host Graphiti
and three subproject split from GMF (Tooling, Runtime and Notational,
see bug report for details).
The objectives of the Graphiti project are the following:
<li>Provide an easy to use and well structured plain Java API for
building graphical tools</li>
<li>Provide documentation and tutorials for doing so</li>
<li>Limit the dependencies of the framework to an absolute minimum
to support RCP-like scenarios</li>
<li>Provide optional components beyond the RCP use case to ease
e.g. IDE integration</li>
<li>Provide the ability to use any existing layout algorithms for
auto layouting a diagram</li>
<p>As the <a href="">Graphical
Modeling Framework (GMF)</a> already exists as a project targeting a similar
objective, we distinguish Graphiti from GMF as follows:
<table border="1">
<td><b>Architectural Concept</b></td>
<td>runtime centric API</td>
<td>refers to GEF functionality</td>
<td><b>Client Logic</b></td>
<td>centralised (feature concept)</td>
<td>functionality distributed since there are no constraints</td>
<td>sophisticated default Look&amp;Feel defined by usability
specialists (highly customisable according to the tool requirements)</td>
<td>simple default Look&amp;Feel (highly customisable according
to the tool requirements in generated coding)</td>
The Graphiti framework utilises Eclipse's
<a href="">GEF</a>
<a href="">Draw2D</a>
for diagramming and supports EMF on the domain side. The diagrams are
described by a platform independent metamodel and the diagram data is
kept strictly separate from the domain data. This enables rendering an
existing diagram in various environments (besides Eclipse this could be
e.g. within a browser) even without having access to the underlying
domain data. This also enables displaying a diagram within other
environments (e.g. using flash inside a browser) simply by providing a
new rendering engine for the environment that can interpret the Graphiti
diagram. (Currently only a rendering engine for Eclipse GEF exists.)
<p>Graphiti is strictly API-centric: a user of the framework writes
plain Java coding and (besides Graphiti) only needs to know EMF to use
the framework and to build an editor -- no knowledge of Draw2D or GEF
(or any other used rendering framework) is required.
<p>Editors built with the framework are equipped with a standardised
Look&amp;Feel (designed together with usability experts) which leads to
a more coherent UI in Eclipse-based tools; nevertheless tools can easily
define a somewhat different Look&amp;Feel according to their special
needs by simply overriding and changing the default behaviour of the
framework. Rapid prototyping is supported by simple APIs and base
classes which can be used to refine an editor in an evolutionary way.
The user of the framework writes so-called features to add functionality
to the editor. For instance, one would write features for creating new
model objects and their graphical representation (Create Features), or
for creating a graphical representation for an already existing model
object (Add Features). The complete life cycle (creating, editing,
renaming, moving, deleting...) of model objects and their graphical
representations can be defined and controlled by implementing such
features. The standard behaviour for the different operations is covered
by so-called default features, if the user of the framework does not
declare any special behaviour. Step by step, these default features can
be replaced or extended with further functionality. Additionally, the
framework comes with a hook for so-called custom features to implement
non-standard behaviour and further operations inside the tool.
The following diagram visualises the framework as perceived by a tool
<p><img alt="Architecture of Graphiti" src="archtools.png">
<p>The Interaction Component is provided by Graphiti, whereas the
Diagram Type Agent (DTA) is implemented by the user of the framework and
defines the new diagram type that is contributed by the tool. It
provides one or more Tool Behaviour Providers that define how the tool
behaves in specific situations; the tool can influence, e.g., what will
be displayed in the palette of the editor, how selection and double
clicking is handled, that some special rendering is necessary for
certain objects, how zooming is handled and so on. It is also the
responsibility of the Tool Behaviour Provider to define which context
menu and context buttons are available in a certain scenario. The
context buttons appear around the currently hovered shape and can be
used by the user in a very convenient way to trigger object specific
operations; they are completely rendered by Graphiti. The tool only
provides the operation, a name, and potentially an icon for it. Of
course, operations can also be triggered via context menu entries.
<p><img alt="Context Buttons" src="ContextButtons.jpg">
<p>These operations are defined by the tool by implementing features
or by using the default features provided by the framework. Besides,
there is a so called Feature Provider for a diagram type which is
responsible to define the features that are available and are to be used
in the tool in a specific scenario.
<h2>Relationship with other Eclipse Projects</h2>
<li>Graphiti uses EMF on the domain side.</li>
<li>Graphiti uses Draw2D and GEF for diagramming.</li>
<li>Graphiti complements the offering of GMF which follows a
generative approach while Graphiti follows a runtime-oriented and API
based approach.</li>
Besides that proposed Eclipse project
<a href="">WTP/JPA
Diagram Editor</a>
already uses Graphiti as its underlying graphical framework.
<h2>Initial Contribution</h2>
The initial code contribution will come from
<a href="">SAP</a>
where Graphiti was developed originally as part of their MOF based
modeling infrastructure. Later Graphiti was ported to EMF; this version
will be the basis for the coding contributed to Eclipse.
<h2>Legal Issues</h2>
There are no known legal issue with Graphiti.
<p>The following individuals are proposed as initial committers to
the project:</p>
<li>Michael Wenz, <a href="">SAP</a>, lead</li>
<li>Christian Brand, <a href="">SAP</a></li>
<li>Matthias Gorning, <a href="">SAP</a></li>
<li>Tim Kaiser, <a href="">SAP</a></li>
<li>J&uuml;rgen Pasch, <a href="">SAP</a></li>
<p>The following Architecture Council members will mentor this
<li>Cedric Brun, <a href="">Obeo</a></li>
<li>Bernd Kolb, <a href="">SAP</a></li>
<h2>Interested Parties</h2>
<p>The following individuals, organisations, companies and projects
have expressed interest in this project:</p>
<li>Ronald Steinau, <a href="">Entimo</a></li>
<li>Jens von Pilgrim, <a href="">FernUniversit&auml;t
<li>Markus V&ouml;lter, <a href="">itemis</a></li>
<li>Jan K&ouml;hnlein, <a href="">itemis</a></li>
<li>Alexander Ny&beta;en, <a href="">itemis</a></li>
<li>Dimitrios Kolovos, <a href="">University
of York</a></li>
<li>Eike Stepper, Lead <a href="">CDO
Model Repository</a></li>
<li>Mickael Istria, <a href="">BonitaSoft
The need for a runtime-centric graphical framework enabling easy
development of graphical editors in EMP was discussed at the Eclipse
Summit Europe 2009 with the above-mentioned parties.
<h2>Project Scheduling</h2>
We will be present with Graphiti at
<a href="">EclipseCon 2010</a>
to raise the community awareness of the project. There will be a
<a href="">talk
on Graphiti</a>
and we will have a
<a href="">poster at
the poster reception</a>
. We plan the initial code contribution for end of March 2010 and hope
to have an incubator release by June 2010, aligned with the Helios
release. Also after the initial code contribution we plan to open the
project for further contributors from other interested parties.
<h2>Changes to this Document</h2>
<td>December 15, 2009</td>
<td>Document created</td>
<td>March 18, 2010</td>
<td>Document updated</td>