Writing Effective Use Cases for the Declarative 3D
for the Web Architecture
Jacek Jankowski
Digital Enterprise Research Institute, NUI Galway, Ireland
jacek.jankowski@deri.org
ABSTRACT 2. USE CASE STRUCTURE
In this paper we present a guide for writing use cases for the There are several components of a use case which we believe
Declarative 3D for the Web Architecture, use cases where are essential when writing use cases for the Declarative 3D.
embedding 3D data in HTML using declarative approach In the following we will describe these components [2, 3].
provides significant benefit. We list components of a use
ID: Unique identifier to represent a use case
case which we believe are essential when writing use cases
and then we walk through a simple use case example. We Title: Short and informative name of a use case
believe that thanks to properly described use cases, it will
Priority: 1-Very Important, 2-Important, 3-Optional
be much easier to deduce different required dimensions for
the Dec3D specification. Actors: In this document, we consider Publishers and Users.
For simplicity, we give our fictitious users first names whose
Categories and Subject Descriptors first letter matches their role: Paul, Peter, Patrick and Penny
are publishers; Ula and Ulrich are users.
H.5 [Information Interfaces and Presentation]: Hyper-
text and Hypermedia; I.3.7 [Computer Graphics]: Three- • Paul - math teacher running MathBlog - a blog dedi-
Dimensional Graphics and Realism cated to promoting the beauty of Mathematics; knows
basic HTML;
Keywords • Peter - scientist who writes web-based articles on his
Declarative 3D, Use Cases website BioScienceSite, where he discusses proteins,
genes, etc; knows HTML and is experienced in using
3D modeling software (Blender, 3DS Max);
1. INTRODUCTION
• Patrick - professional web developer working for Dev-
The Declarative 3D for the Web Architecture W3C Commu- Masters; he has good knowledge of HTML, JavaScript,
nity Group1 has been formed to explore and suggest options CSS; currently working on VirtualMuseum and Car-
for new declarative ways of incorporating 3D graphics di- Configurator projects;
rectly into HTML to enable its use on any Web page. The
core mission of the Declarative 3D Community Group is • Penny - museum curator, working with Patrick on a
to determine the requirements, options, and use cases for virtual museum exhibition called VirtualMuseum; she
the declarative integration of interactive 3D graphics capa- has good knowledge of 3D scanning technologies;
bilities into the Web technology stack which will provide a • Ula and Ulrich are typical Internet users; they have
foundation for future standardization. good understanding of hypertext-based Web interac-
Therefore, in this paper we aim to create a guide for writing tion; Ula is an accountant and has little experience
effective use cases for the Declarative 3D [2, 3], use cases with 3D graphics; Ulrich is a math and biology stu-
where embedding 3D data in HTML using declarative ap- dent, who occasionally plays 3D games.
proach provides significant benefit. We list components of
a use case which we believe are essential when writing use We believe that such short user stories can help to set the
cases and then we walk through a simple use case example. stage for use cases by building up the context.
We believe that thanks to properly described use cases, it Description: Short and simple (plain English) description
will be much easier to deduce different required dimensions of a use case. The purpose is to effectively transfer knowl-
for the Dec3D specification. edge from the domain expert to the software developer.
Starting code: Starting sudo-HTML code
Complete code: Sudo-HTML, after declaring 3D scene.
Using the web site: Description of end-user interaction
with a web site (support for Web and 3D tasks [4]).
1
Declarative 3D homepage: http://declarative3d.org
Derived requirements: Functional and non-functional re-
quirements derived from a use case.
Copyright c 2012 for the individual papers by the papers’ authors. Copy-
ing permitted only for private and academic purposes. This volume is pub-
Screenshot/Demo: Depiction of expected design, screen-
lished and copyrighted by its editors. shot, or a link to a working demo (created in e.g. [1, 5]).
Dec3D2012 workshop at WWW2012, Lyon, France
3. USE CASE EXAMPLE
In the following we describe a very simple use case for Declar-
ative 3D. We hope that such description can be leveraged to
create more complex use cases in future.
ID: Use Case UC101
Title: MathBlog - Adding basic 3D geometry to a post
Priority: 1
Actors: Paul, Ulrich
Figure 1: Screenshot of MathBlog with basic 3D
Description: Paul, who maintains a MathBlog, wishes to geometry.
enrich his new post about geometric figures with 3D repre-
sentations of those figures. For this purpose, he chooses to
use shape nodes and declare them in the HTML. 4. CONCLUSIONS AND FUTURE WORK
Starting code: Paul’s starting HTML (before declaring In this paper we presented a guide for writing use cases for
3D) is presented on the Listing 1. the Declarative 3D for the Web, use cases where embed-
ding 3D data in HTML using declarative approach provides
1
2 < t i t l e>P a u l s Blog significant benefit. We believe that thanks to properly de-
3 scribed use cases, it will be much easier to deduce different
4 ... required dimensions for the Dec3D specification.
5
6 G e o m e t r i c F i g u r e s Having a use case catalog, such as at Declarative 3D Com-
7
munity Group Wiki is beneficial, however, a certain problem
8 The cube i s a 3D s o l i d o b j e c t bounded remain: the size and variety of the use case space and its
9 by s i x s q u a r e f a c e s , f a c e t s o r s i d e s ,
10 with t h r e e meeting at each v e r t e x . lack of graphical representations limit its usefulness in the
11
use case discovery, exploration and understanding process.
12 ... In order to address this issue we propose to employ interac-
13
14 tive, visual aids to assist users, allowing finding relevant use
15 cases both efficiently and effectively. As the human brain
enables us to see, explore, and understand large amounts
Listing 1: Starting Code of visual information at once, we want to focus on the cre-
ation of an interactive (possibly 3D) use case diagram and
Complete code: Paul’s HTML, after declaring 3D scene, elements to visualise information about different characteris-
is presented on the Listing 2. tics of use cases. Data visualisation techniques (e.g., graphs,
trees, etc.) in tandem with graphical capabilities of mod-
1 ern browsers, can be used to present use cases in innovative
2 < t i t l e>Paul ’ s Blog
3
ways. We believe that, as a result, users will be able to easily
4 ... identify relevant use cases, unearth previously unseen corre-
5 lations between them, or learn about related requirements.
6 G e o m e t r i c F i g u r e s
7
* Visit http://declarative3d.org and contribute with your
8 The cube i s a 3D s o l i d o b j e c t bounded use cases for the Declarative 3D for the Web.
9 by s i x s q u a r e f a c e s , f a c e t s o r s i d e s ,
10 with t h r e e meeting at each v e r t e x . ** This work has been supported by SFI under Grant No.
11
SFI/08/CE/I1380 (Lion II) and by EI under Grant No.
12 PC/2008/353 (Copernicus).
13
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5. REFERENCES
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