Representation and Visualization (Museums and Cultural Heritage)
Summarising digital tools for the representation and visualization of cultural heritage is difficult, but perhaps not as difficult as defining what range of objects those representations might need to describe. The list of entities that could potentially be relevant include: historic environments, architecture, acoustic spaces, maritime and underwater landscapes, everyday objects, tools, building materials, toys, books, comics, artworks, sculpture, etc. It is of course possible to create period-specific representations of a huge variety of artefacts and locations in existing virtual environments, the most prominent of which is currently Second Life, and references to the existence of a Victorian village within that virtual world indicate that such attempts are already being made. Ultimately how plausible and useful these environments will prove to be in terms of advancing research across the MCH sector may depend on a number of factors, principally perhaps the levels of participation and the amount of genuinely interesting material that is created within these virtual worlds, two issues that are clearly mutually-dependent.
The King’s Visualization Lab (KVL) and partners are beginning work on a collaborative project called SLEUTH (Second Life Educational Undertakings in Theatre History) to import existing 3D models of historical theatres into Second Life. The models were created as part of the EU funded THEATRON project in 2002 and bring an enormous amount of added value to the project in terms of the scholarly value originally invested in their creation. It is anticipated that these visually complex and high quality models will form the basis of a learning environment that can be used by a range of disciplines including history, performing arts, the study of dramatic literature and architectural and urban design.
Well established tools such as 3D Studio Max, Maya, AutoCAD, SolidWorks, and the free open source system Blender are all highly sophisticated programmes capable of constructing and rendering three-dimensional spaces, some of which are referred to in slightly more detail in the working paper on ‘Archaeology’. (Alternative packages including additional open source options are featured on the EPOCH tools list, grid ref. 5E – Virtual Models VR/AR). The sort of results that can be achieved by expert use of these systems are extremely impressive and can deliver images that facilitate innovative research.
At a recent Methods Network seminar entitled Theoretical Approaches to Virtual Representations of Past Environments, several of the participants demonstrated work representing a range of pictorial approaches which was followed by discussions about ways of documenting and explaining the underlying data that such representations were based on. This is an issue which is very much at the centre of an ongoing initiative called the ‘London Charter’55 which is a collaborative attempt to formalise and ratify principles for 3D visualization methods which will enhance research outcomes and assist in their dissemination to wider communities.
Other approaches to visualization demonstrated at this same event included a wire frame model showing the architectural structure of Rievaulx Abbey
and the Materialising Sheffield: Re-Presenting the Past project, which shows how Benjamin Huntsman’s Attercliffe Works would have appeared during the period 1771-1781. Original ground plans and elevations were scanned into AutoCad58 and then overdrawn to produce 2D drawings. 3D models were produced by extruding these elements and using repeating sections where appropriate to build up volumes for the buildings and to be economical in terms of the size of the eventual 3D image files. Raster images of textured surfaces such as brick walls were applied to the 3D vector model and other images of trees and foliage were acquired to also add verisimilitude to the virtual environment. In order to add a sense of human presence to the scene, actors were filmed carrying out activities against a blue-screen backdrop and these were then placed into the virtual environment. The use of a volumetric particle system to represent smoke coming out of the chimneys of the melting house contributes to the dynamism and realism of the scene and all the elements are tied together using software lighting systems that reproduce the light coming out of the fire pits, through the open windows and ambiently in the external scenes. A number of illustrations and animations are available, copyright of the Humanities Research Institute and their technical media partner, Red Star Studios.
The open source system Radiance is an example of ray tracing system which allows developers of 3D models to introduce plausible lighting schemes across environments or onto objects. Comprising of a suite of over 50 tools, it was designed to work with a command-line interface on Unix and Unix-type systems and demands quite high levels of user knowledge. Very sophisticated results can be achieved however that can be used for examining the impact of different lighting conditions within a historic environment or a heritage related space.
[img_assist|nid=264|title=Fig. 4. Example of complex interior lighting scheme using Radiance|desc=|link=node|align=center|width=640|height=469]
Useful representations of heritage-related environments can be further extended to include the audio properties of such spaces and this was also demonstrated at the recent Goldsmith’s seminar. Damian Murphy (University of York) presented the acoustic modelling work that he and others had carried out in a number of different environments and usefully illustrated the complementary ways in which aural and spatial research can be combined to add additional value to 3D digital models. His presentation referred to work carried out in the Hamilton Mausoleum (built 1848-1857), a space that sustains sounds as echoes for fifteen seconds or more, and also Maes Howe in Orkney, a chambered cairn dating from 2450 B.C. that was studied for evidence of its resonance properties in order to determine whether this could shed light on the likely uses that the space was dedicated to. Acoustic measurement tools determined that strong standing wave effects that are well within the lower male vocal range were present within the interior, suggesting possible use as an effective location for ritual practices involving the use of the human voice.
[img_assist|nid=263|title=Fig. 5 Acoustic research at the Hamilton Mausoleum (Damian Murphy – University of York)|desc=|link=node|align=center|width=551|height=170]
Also resulting from research based at the University of York, Roomweaver is a Digital Waveguide Mesh (DWM) based tool that has been designed to ease the development and application of DWM models for virtual acoustic spaces. The tool has the capability of generating Room Impulse Responses (RIR) and 3D models of the spaces under consideration and features a mixture of GUI and command line interfaces for the user to interact with the programme.