2. Use Case
In addition to enriching our cultural heritage sector, performance, as research, underpins the
scholarly record and is commonly used, reused and reinterpreted by subsequent researcher-
practitioners as the basis for new works. The target audience for this system is the
undergraduate through to a post-doctoral researcher studying in a performance-related
discipline (e.g. theatre, live art or dance).
Locally, the system is intended to be used by undergraduates studying performance within the
University of Bristol's Department of Drama to build 3D 'sketchbooks'. 3Dactyl is presented as a
solution which will permit 3D recordings to be made, studied and ultimately archived for
Students, researchers and keepers of performance study collections recognise both the
desirability and the considerable challenge of 'preserving' live performance. Often a single video
recording is used to represent a work which may have taken months or even years to develop.
products’ of the creative process, these videos may be of very poor quality. Problems are
associated with using any single method of documentation, but video has an inherent limitation:
it is essentially a 2D technique attempting to describe actions in 3D space. For disciplines
where correct execution is important, such as dance, established visual recording methods
frequently produce documents which are entirely unfit for research or teaching purposes.
42 UK Higher Education institutions (HEIs) and similar institutions put forward research for
assessment under the Drama, Dance and Performing Arts heading of the 2008 RAE. The
University of Bristol Department of Drama: Theatre, Film, Television was ranked 6th among
them. The University is also home to the Theatre Collection, a special study collection and
museum which holds the second largest performance-related archive in the UK, after the
Victoria and Albert Museum.
After conducting several successful collaborative projects with the Department of Drama the
3Dactyl team recognised the need for an inexpensive and easy-to-use system which could be
deployed to record performance in an interactive 3D format.
The system should be unobtrusive (for example, not require special markers to be worn during
recording) and sufficiently accurate, as well as be able to produce documents in a format which
can be accessed via a browser without the need for dedicated plug-ins. The solution will allow
students and researchers of performance to interact with 3D representations in real time and to
examine the event from any conceivable perspective, for example, from behind, above or at
very close range. This need ruled out the use of domestic 3D TV technologies, which record
and display stereoscopic rather than truly 3D representations, in much the same way as
conventional cinematic projections differ from 3D vision performances.
If possible, documents produced by the system should be in an open source format in order to
meet the collection policies of archives such as Bristol’s Theatre Collection Museum
the custodian of much of the UK’s performance documentation.
Tools which facilitate online 3D representations have been around for some time. Introduced in
the early 1990s, VRML (Virtual Reality Mark-up Language) was limited by insufficient
bandwidths, processor speeds and the need to employ browser plug-ins which proved difficult
to configure. Despite these issues, VRML ultimately proved to be a successful, open
technology and spawned the newer X3D format. The X3D ISO standard, used by the 3Dactyl
system, offers the ability to encode a 3D scene using an XML dialect. Supporters of X3D are
currently striving to make it the de facto standard for interactive 3D Web content.
X3D, coupled with advances in WebGL (Web-based Graphics Library) and intermediary
mean many of today’s browsers are already capable of displaying
data without the need for plug-ins, although this functionality is rarely used.
The online re-presentation of human motion is only possible if that motion has been accurately
captured, to achieve this, the current project makes use of the Microsoft Kinect, an inexpensive
peripheral, primarily intended as a controller for the Xbox 360. The release by Microsoft of the
University of Bristol Theatre Collection, http://www.bris.ac.uk/theatrecollection/