Victor DeLeon, USA | ISBN: | Submitted: Apr 29, 1999

VRND: NOTRE-DAME CATHEDRAL: A Globally Accessible Multi-User Real-Time Virtual Reconstruction

VRND: NOTRE-DAME CATHEDRAL

A Globally Accessible Multi-User

Real-Time Virtual Reconstruction

Victor. J. DeLeon Digitalo Design, Incorporated, vic @digitalo.com www.digitalo.com 13090 Vista Isles Drive, Suite 125, Sunrise, Florida, USA.

ABSTRACT

This research will be based entirely on three-dimensional architectural and photographic data leading to the accurate reconstruction and 3-dimensional presentation of a multi-user virtual reality rendition of the cathedral, accessible to the public from anywhere in the world. The results derived from this accumulation of data will be precise and as scientifically accurate as possible within the means of our employed technologies, focusing around a new core technology which specifically deals with presenting complex environments comprised of textured polygonal sets of information to a low-end audience. The focus of this project is to reconstruct the edifice in as much detail as possible. As an added culturally significant value, some basic historical facts will be presented to the viewer in the form of a “virtual tour guide.EWe anticipate capturing the attention of historians, architects -- both scholars and students -- preservationists, artists, and tourists on a global level. The VRND Project, A Globally Accessible Multi-User Real-Time Virtual Reconstruction will be housed on both CD-ROM and a high-speed Internet Server, thus allowing thousands of visitors, those unable to experience the Cathedral in person, to access this reconstruction from anywhere around the world on their computers, whether in their classrooms or from home. The VRND Project will not only be something that you can experience, but more importantly, it is envisioned as a learning tool. A tool that will transport viewers into the Cathedral itself, learning about its rich culture and history firsthand.

1. Introduction

"Sans doute, c’est encore aujourd’hui un majestueux et sublime edifice que l’eglise de Notre-Dame de Paris. Mais, si belle qu’elle se soit conservee en vieillissant, il est difficile de ne pas soupirer, de ne pas s’indigner devant les degradations, les mutilations sans nombre que simultanement le temps et les hommes on fait subir au venerable monument, sans respect pour Charlemagne qui en avait pose la premiere pierre, pour Philippe-Auguste qui en avait pose la derniere."

- Victor Hugo, Notre-Dame De Paris [1865] 1

Notre-Dame de Paris is arguably the best known cathedral in the world. It has witnessed events such as Napoleon’s coronation and the marriage of Mary Queen of Scots. In 1163, the new Bishop of Paris, Maurice de Sulli, planned to erect a new monumental cathedral the likes of which no man had ever seen. It was to be named La Cathedrale de Notre-Dame de Paris. Notre-Dame’s construction initially took over 200 years. Since then, several additions have been made to the exterior and interior of this massive structure [2]. The sad truth is that this nearly nine hundred year-old monument to man’s spirit is in a perpetual state of reconstruction and preservation. Over fifty thousand people visit the cathedral every day, making the efforts of architects and preservationists a difficult task. Their work, however, continues at a tireless pace [3].

Futurists and Technology Trend Scholars have predicted that someday we will not need to travel across the globe to visit monuments; we will simply select them from an interactive encyclopedia and "virtually" visit them from our classrooms and living rooms [4]. Imaging technologies have been advancing in great leaps and bounds, as have processing and display manufacturing. The costs have dropped so steeply that most of this technology is cheap enough and readily available to most consumers today.

The two aforementioned issues, although seemingly unrelated, bring us to the focus of this project. What if it was possible to visit La Cathedrale de Notre-Dame de Paris, without ever leaving your home or classroom? What if professors could lecture and teach classes from within the walls of the cathedral from anywhere on the planet? What if preservation specialists and architects could use the "virtual workspace" to better plan out their efforts? Someday technology will make these scenarios a possibility [5]. This proposal focuses on a project, which is based on a newly developed core technology that has, in theory and application, made these future possibilities a reality today.

2. Proposal

2.1. Intellectual Content

Notre-Dame Cathedral is considered by many to be one of man’s most crowning architectural achievements of this millennium. A symbol of man’s perseverance and ingenuity, this edifice has withstood wars, fires, revolutions, and the endless battering of the elements. It is a tribute to man’s desire to become closer to God. Notre-Dame de Paris has become the most respected religious, historical, and cultural icon in Europe [6]. The VRND Project Team feels that this monument should be immortalized for future generations to experience, as well as for the education, cultural and historical awareness for present-day audiences to enjoy.

This research will be based entirely on three-dimensional architectural and photographic data leading to the accurate reconstruction and 3-dimensional presentation of a multi-user virtual reality rendition of the cathedral, accessible to the public from anywhere in the world. The results derived from this accumulation of data will be precise and as scientifically accurate as possible within the means of our employed technologies, focusing around a new core technology which specifically deals with presenting complex environments comprised of textured polygonal sets of information to a low-end audience. The focus of this project is to reconstruct the edifice in as much detail as possible using mathematical and visual measurements, which are not subject to speculation. (Rather than on often historically biased interpretive accounts of data surrounding the construction.) It should be noted however, that as an added culturally significant value, some basic historical facts would be presented to the viewer in the form of a "virtual tour guide."

The project team will be taking a solid and concise approach towards presenting the subject in a well-designed and user-friendly manner. We anticipate capturing the attention of historians, architects -- both scholars and students -- preservationists, artists, and tourists on a global level. Approximately 50,000 people visit the Cathedral of Notre-Dame every day making it one of the most popular cultural attractions in Europe [7]. The VRND Project, A Globally Accessible Multi-User Real-Time Virtual Reconstruction will be housed on both CD-ROM and a high-speed Internet Server, thus allowing thousands of visitors, those unable to experience the Cathedral in person, to access this reconstruction from anywhere around the world on their computers, whether in their classrooms or from home. The VRND Project will not only be something that you can experience, but more importantly, it is envisioned as a learning tool. A tool that will transport viewers into the Cathedral itself, learning about its rich culture and history firsthand.

2.2. Impact and Collaboration

The impetus of this project has already expanded to an international scope involving artists, researchers and technical specialists from around the United States collaborating with architects, programmers, and historians overseas. The national research team, based in Fort Lauderdale, Florida, is presently collaborating with team members from universities all across the U.S. Additional researchers from France and Japan have been recruited, making this an international collaborative effort. The organizations and independent researchers have wholeheartedly committed themselves to doing whatever is necessary to bring this vision to fruition. Several steps have already been made to facilitate communication between the team members such as videoconference systems, listserves, email bulletin boards, and websites. Several involved parties have already begun a software and hardware exchange to simplify the collaborative development environments. Several team members are also organizing preparations for video documentation, research papers, and journal publications

2.4. The Audience

The audience for this project has been clearly defined. The widest appeal will be for historians and architects -- both scholars and students -- preservationists, artists, tourists, and anyone interested in the humanities. By housing the VRND Project on both an Internet server and CD-ROM, it will be possible to attain a global audience. Anyone with access to a standard computer, PC or Macintosh will be able to witness firsthand this truly unique experience. People will be informed about the project via a robust Internet marketing campaign as well as a standard press release promotion to all pertinent journals, periodicals, and magazines. Public Television and Web-Broadcast interviews and shorts may also be promoting the project. A large amount of publicity will be spawned from the technical conferences which will be displaying the project via interactive computer kiosks, as well as presentations, papers, and workshops. Most importantly, a full video documentary will be released shortly after the completion of the project. It will serve to document the team’s work, as well as to promote the entire project for public broadcast and encourage similar projects on a global level.

2.5. Resources

The archives, collections, and other resources are already present and the necessary data have been clearly identified. The Project Team’s established guidelines are comprehensive enough for the team to extrapolate information and proceed with the architectural reconstruction in an organized and professional manner. A working relationship is being established with the Centre de Recherches sur les Monuments Historiques in Paris. Architectural blueprints, historical archives, and all other necessary documents will be made available to the design team to ensure a successful outcome.

3. Technical Processes

3.1. Data Acquisition

The majority of the data for the structure will be acquired during the on-site phase in Paris. Several different types of resources will be needed to reconstruct the cathedral accurately and in proper scale. Pencil sketches will be made of the entire interior, which will be copied and number-coded to serve as a reference and checklist. Measurements will be made via blueprints and official sources. Some measurements will be made on-site using sonic and laser-based measuring devices to insure accuracy. High-resolution digital cameras will be used to capture textures for the walls, columns, stained glass etc. The textures will be uploaded to a server on a daily basis to allow other team members to process and manipulate the images and their respective color palettes to implement them into the 3D engine at a later time.

3.2. 3D Modeling & Texture Mapping

The first step will be to identify and classify the various different types of structures within the cathedral and categorize them respectively. This is to insure that the designers will be able to work efficiently with each different type of structure (columns, arches, doorways, etc.) one at a time. Next, photos will be taken of each structure so that they may be number-coded and easily identified between team members. Team consensus will be sought to optimize certain aspects of each model’s complexity prior to its actual construction. To maintain a modest polygon count within the reconstruction, each model’s potential intricacy (mesh density) will be discussed. The choice to use increased polygon count versus using "trompe-l’oeil" textures for each individual structure will be thoroughly thought out. What follows will be a long and arduous process of modeling each individual structure manually (without the aid of laser digitizing) in various 3D modeling packages and incorporating the textures to compensate for the details within the simplified models.

3.3. The Virtual Tour Guide

The character mesh for the virtual tour guide will be designed and fully animated in external modeling packages and imported using conversion utilities into 3D Studio Max, then into the VRND’s 3D environment. A 1200-1500 polygon mesh with photo-texture maps and a fully jointed skeleton will be used. All the necessary pre-determined animation sequences would be saved and also exported. Next, several programmers will focus on incorporating these actions into the simple AI behavior engine so that the guide will "come to life". Certain behaviors will be scripted into the tour guide’s character permitting him to either lead users or follow them around the cathedral. The tour guide will be able to point out the many points of interest within the structure and offer explanations. These behaviors will be scripted using triggers or proximity sensors that will be set up in certain areas of interest. These areas will be planned out by the historical consultants and in turn, coded by the programmers and scriptors.

4. Conclusion

Some basic foundational concepts of virtual reality research focus on the need for realism. It is this realism or "impression of reality" which leads the user into a state that is commonly referred to as "immersion" or the total suspension of disbelief [5]. Eventually, the technology will become transparent to users, creating unique and truly real learning experiences of their own. Having spent over four years on similar projects involving reconstruction in virtual reality, the individual members of the VRND Project Team will continue to strive in maintaining the natural beauty of organic as well as manmade structures, paying close attention to the emerging technologies on the horizon. What they have found in the process is that it is possible to employ less orthodox means to arrive at a nearly impossible goal within a modest budget. Virtual reality is still considered by many to be in its infancy, therefore, it is given that the proper tools and skills necessary for its ideal construction are limited only by what previous research has forged to this day [8]. The members of the team will continue to strive for the ultimate artificial experience, and as the tools become more sophisticated, so will their efforts. With the growing support of UNESCO, academia, and corporate sponsors along with the foresight of conferences like the VSMM, research and development in VR systems like the VRND Project will continue to advance. Hopes are that this new generation of low-end and low-cost VR systems will open new exhibit opportunities to the schools, museums and exhibition halls of the world. The vision that children and adults will someday know exactly what it feels like to visit a place that they might only have been able to dream about has become a reality.

Acknowledgements

The author would like to thank Barry L. Gibbs, VRND Project Coordinator, Digitalo Design, Inc. for his assistance on both the research paper and the proposal, as well as the demo and website. Many thanks to Takeo Ojika, Scot Thrane Refsland, and Bob Berry, Virtual Systems Laboratory, Gifu University, Japan, for their technical assistance and moral support. Tim Sweeney and Mark Rein, Epic Games, USA, for their technical assistance. And lastly Dr. Edmund Skellings, Francis X. McAfee, Diane Newman, John Muehl, and the entire research staff at the Florida Center for Electronic Communication.

Bibliography

[1] Hugo, Victor (1865). Notre-Dame De Paris. J.Hetzel et A. Lacroix, editeurs

[2] Smith, K.L. (1955). People, Pomp, and Circumstance. Blackmore Press, NY

[3] Anderson, R. G. (1945). The Biography of a Cathedral. Longmans, Green and Co., NY

[4] Krueger, M. (1990). Artificial Reality, Addison-Wesley, CA

[5] Holtzman, S. (1998). Digital Mosaics, The aesthetics of Cyberspace. Simon & Schuster, NY

[6] Erlande-Brandenburg, A. (1998). Notre-Dame De Paris. Abrams Publishing, NY

[7] Ruck, A. (1996). Fodor’s Exploring France. Fodors, Random House, NY

[8] Fisher, S. (1990). Virtual Interface Environments, The art of Human-Computer Interface Design. B.Laurel (ed.), Addison-Wesley, CA

[more information]
http://www.digitalo.com/deleon/vrnd/vsmm99/index.html

[other authors]
Robert Berry

[keywords]
Virtual Reconstruction VR Notre-Dame UNESCO DeLeon