Pure Land
Date : 17 – 20/5/2012
Time : 17 - 19/5, 12 - 6pm
20/5, 12 - 5pm
Venue : Hong Kong Convention and Exhibition Centre
Co-presented with

Event Partner

On invitation of the HK Art Fair 2012, CityU is presenting Pure Land – Inside the Magao, a seminal research project that envisions the future of digital preservation, cultural heritage interpretation and an embodied museography.

The booth dimensions at the HK Art Fair are almost identical to those of Cave 220 at Dunhuang. This presentation is an innovative ‘augmented reality’ installation whereby the paintings and sculptures of that cave are virtually rendered with the architecture of the booth. This imagery is made visible on iPad screens that visitors can hold in their hands and use as mobile viewing windows - in this way they can see and explore every feature of the actual cave within the perimeter of the HK Art Fair booth.

This highly original technical achievement is afforded by a number of infra-red cameras in the booth that accurately track the position and orientation of these iPads. Computers then render the appropriate views of the actual Dunhuang cave, which are sent to the iPad screens via Wi-Fi.

The walls of the HK Art Fair booth are covered with full-scale photographic prints that show laser scans of the architecture of Cave 220 made by the Dunhuang Academy, and these also provide a structural and aesthetic alignment between the space of the booth and that of the cave.

The original laser scans have been converted into a 3D polygonal mesh, which form the virtual surface structure onto which the Dunhuang Academy’s high resolution photographs of Cave 220’s paintings and sculptures are rendered. This composite 3D representation is what becomes viewable on the iPad screens.

The presentation at the HK Art Fair 2012 is a world’s first, showing the future of mobile media as a means of virtually embodying 1:1 scale cultural heritage experiences. It creates a space of conjunction between real and virtual formations that gives transacted aesthetic expression to the Dunhuang’s treasury of wall paintings and sculptures. It has been produced at the CityU Centre for Applied Computing and Interactive Media (ACIM).

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Pure Land:
Inside the Mogao Grottoes at Dunhuang

Pure Land immerses visitors in the quintessential heritage of hundreds of Buddhist grotto temples, an art treasury abounding with murals, statues and architectural monuments. This UNESCO World Heritage site, also known as the Caves of the Thousand Buddhas is located at Dunhuang a small town in northwestern China, an oasis in the Gobi desert. It was a gateway to and from China on the ancient Silk Road, which carried trade between China, western Asia and India from the 2nd century BC until the 14th century AD for over 1000 years.

Using pioneering virtual reality technology, artists and scientists at CityU have developed an extraordinary new animated 3D experience. Visitors are immersed in a large 360-degree panoramic projection theatre that gives a true-to-life experience of being inside a cave temple and seeing its magnificent Buddhist wall paintings at one-to-one scale. Figures and objects in these paintings are dramatized by means of spectacular interactive 3D animations and digital effects that reveal their painterly beauty and underlying narrative meanings.

Pure Land brings to life the story painted as a single composition on the north wall of the Cave 220, known as Bhaisajyaguru’s Eastern Paradise. The detailed mural depicts the paradise Eastern Pure Land of the Medicine Buddha, Bhaisajyaguru. It shows the seven forms or emanations that Bhaisajyaguru can assume as a healer. They stand in a row on lotus platforms with a lotus pool below and, as in the painting opposite, a group of musicians accompanying dancers. The Bhaisajyaguru sutra tells of the twelve great vows of the Buddha, relating to the provision of food, drink, clothing, medicine, and spiritual aids. Devotees were encouraged to light lamps in worship and this is depicted in this painting to either side of the musicians and in the altar with lamps between the dancers.

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Mission of the Dunhuang Academy

Founded as an institution dedicated to the management, protection and research of a world heritage site, the Dunhuang Academy has strived to preserve and promote Dunhuang culture for the past 60 years. At a time when the caves are facing devastation from men and nature alike, we are particularly interested in exploring new means of protection and appreciation. Today, we witness ancient history and new media converge as Dunhuang Academy and City University of Hong Kong worked together to recreate across time and space the timeless splendour of the Buddhist art of Dunhuang. I trust the fruits of this collaboration over the past months would offer new perspectives to, and find resonance with our audience. Such are the new efforts that we have been pursuing in the hopes that the cultural heritage of our humanity may be propagated to a wider audience.

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The Making of Pure Land

Sponsored by Mr Gabriel Yu, Pure Land: Inside the Mogao Grottoes at Dunhuang has been produced by the CityU Applied Laboratory for Interactive Visualization and Embodiment (ALiVE) in partnership with the Dunhuang Academy and the Friends of Dunhuang Hong Kong. Thirty people creatively contributed to this project in various capacities over a six-month period. These specialists include world-leading authorities on art history and the mural paintings of the Mogao Grottoes from the Dunhuang Academy. Based on their advice and art direction, the project’s team of artists and animators were able to the redraw, restore and recolour key iconographic elements in the wall painting, and create its 3D animated objects and dance sequences. Pictorial and digital artists, interaction and sound designers as well as software engineers together implemented the Pure Land scenography based on an interpretive script developed in close consultation with the project’s donor and partners.

Pure Land production process:

1. The Dunhuang Academy provided the project with laser scan data sets (‘point-cloud’ and ‘polygonal’) that describes in detail the architectural shape and sculptural features of Cave 220. The Dunhuang Academy also provided the project with medium resolution photographs of the south, east and west walls, and an ultra-high resolution photograph of the north wall.

2. Project researchers first optimized the 3D model of the cave for ‘real-time’ viewing, and applied the photographic textures to its surfaces to create a full 3D visualization of the cave interior.

3. Working closely with the Dunhuang Academy and the Friends of Dunhuang Hong Kong, the project team developed an interpretation plan for the north wall mural, to provide a framework for the interaction design, the treatment of the imagery and the shaping of 2D and 3D animations.

4. The re-colouring and digital restoration of elements within the original mural was based on extensive art historical research. Using the ultra-high resolution photograph of the north wall, these selected elements were carefully traced, redrawn and repainted on rice-paper, imitating the paint-brush strokes of the original as well as its recolouring. The images created by this meticulous manual process were then digitized and integrated into the animation scenography. Art-historical accuracy was integral to all aspects of this project, including for example the 3D reconstruction of the illustrated musical instruments, and the re-enactment of dance performances represented in the painting.

The animation scenography incorporates a number of different animation techniques. These are:

  • 2D cutouts whereby certain element such as the seven Medicine Buddha’s appear to emerge out of the original mural and these have been repainted in their original colourful state.
  • 2D animation where certain pictorial elements such as Samantabhadra Bodhisattva move and come to life. This labour intensive type of 2D animation requires the creation of 25 hand painted pictures for each second of animation.
  • 3D animation whereby certain pictorial elements such as the orchestral instruments and the Medicine Buddha’s canopies become three-dimensional solid objects floating and rotating in front of the actual painting. The 3D animation techniques used include both scripted and procedural software programs.
  • Live video for the 3D digital recording made of dancers from the Beijing Dance Academy who re-enact the dances shown in the mural painting.

These animation techniques were supplemented by software generated digital effects such as the ‘virtual torch’ that allows the viewer to simulate moving a torch light around in the cave, and a ‘virtual magnifying glass’ that allows the viewer to zoom into the painted surface of the mural and see its details in ultra-high resolution. The project’s sound design is based on research into the traditional Chinese music and the recording of similar instruments existing today - FangXuang (metallophone), PaiXiao (pan flutes), Dizi (flute), Sheng, Yaogu (waist drum), Ruan (lute), Guzheng and Konghou (harp).

All these assets become integrated into the custom developed ‘application software’ that enables this project’s unique interactive ‘virtual reality’ experience to be performed and enjoyed inside a 360-degree stereoscopic projection environment. Pure Land offers two modalities of operation: the guided tour whereby an expert guide provides the audience with a scripted tour and commentary and, the ‘personal discovery’ mode whereby visitors can autonomously and individually explore all the cave’s features.

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New Technologies and the Future of Cave Interpretation

The site of Dunhuang includes 492 caves that still contain rich murals and sculpture (there are over 700 caves in total). In order to ensure the long-term preservation, Dunhuang Academy affirms only open a minimal numbers of caves. Currently in those caves that are open, visitors may use pale torch lights to examine the cave walls while glass windows often stand between the viewer and the wall to ensure protection for the murals.

At Dunhuang there is an obvious tension between the desire to show this rich and important treasury to the world and the ongoing protection of the caves. The dilemma faced by the custodians of the site may be resolved through new technologies and virtual facsimiles such as Pure Land. A New York Times journalist who visited Dunhuang expressed this:

And Mogaoku is in trouble. Thrown open to visitors in recent decades, the site has been swamped by tourists in the past few years. The caves now suffer from high levels of carbon dioxide and humidity, which are severely undermining conservation efforts. The short-term solution has been to limit the number of caves that can be visited and to admit people only on timed tours, but the deterioration continues…Plans are under way to recast the entire Dunhuang experience in a way that will both intensify and distance it. Digital technology will give visitors a kind of total immersion encounter with the caves impossible before now…

- Cotter, H. 2008, “Buddha’s Caves”, July 6, 2008, New York Times

Closing important and unique world heritage caves to ensure preservation is an increasing worldwide practice. France’s Lascaux Caves closed in 1963. In another example, Spain’s famous Altamira Cave has been frequently closed over the past decade and is currently closed due to fungus infestations. Today, when the needs of heritage conservation and preservation are increasingly recognised, digital tools such as laser scanning and high-resolution photography occupy crucial roles in providing continuing access for nonspecialists and scholars to sites under threat. The Mogao Grottoes have been subject to extensive digital imaging for conservation, preservation and education undertaken by the custodians of the site, the Dunhuang Academy. The photographic projects at Dunhuang, unparalleled in scale when compared to other world heritage sites, is a race to ‘capture’ and preserve the caves before any more degradation can occur. Pure Land makes use of this high-resolution photography and laser scanning data and animation and 3D modelling to tell stories about the extraordinary wealth of paintings found in the caves at Dunhuang, a nexus of cultural interchange via the Silk Road between China, India, Persian, Greco-Roman and Central Asia. Using these data sets Pure Land provides a truly representative 1:1 scale virtual facsimile. Cave 220 as with many of the caves, represent opportunities for interpretation and the detailed narrative murals make them potential subjects for innovation in heritage interpretation through animation and 3D modelling. These multilayered features can be explored, analysed and understand as an embodied 3D visual experience embedded in a rich soundscape. The animation it contains bring the narratives to life. Pure Land is at the forefront in the use of advanced technologies for digital preservation, cultural heritage interpretation, and new museography.

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Project Donor Mr Gabriel Yu (Chairman of Executive Committee of Friends of Dunhuang Hong Kong)
Project Conception & Direction Dr Sarah Kenderdine, Prof Jeffrey Shaw (CityU)
Art Direction, Interpretation and Script Writing Ms Lou Jie (Dunhuang Academy)
Cave 220 Dataset Mr Wu Jian (Dunhuang Academy)
Script Writing Chen Qi, Chen Haito, Li Dading (Dunhuang Academy)
Art Advisor Mrs Lee Mei-Yin
(Special Researcher with Dunhuang Academy, Friends of Dunhuang Hong Kong)
Project Manager Leith Chan
Application Software Developer Mo Luk (Jadason Technology)
2D Drawing and Animation Jazz Zhou assisted by He Bei-Chen, Liang Xiao and Shangguan Yan-Qing
3D Animation and Digital Visual Effects Michael Cheung, Max Tong (AniMotion)
3D Instrument Models Jonathan Chan
3D Video Production Percy Fung, Joey Wang, Alex Cheng, Karlo Li (Digital Magic)
3D Cave Modelling Carlo Camporesi (UC Merced), Fabrizio Galeazzi, Marco Di Ioia (VHLab of CNR ITABC)
Interaction Design Tobias Gremmler (CityU)
Sound Design Dr. Cedric Maridet
Dance Director/Choreographer Ms.Shi Min (Assistant Professor, Beijing Dance Academy)
Dancers Miss Wang Xiao-Xiao (Post-graduate Students, Beijing Dance Academy), Miss CHEN Fei-Fei (Intern, Beijing Dance Academy)
Calligraphy Ronald Ip
Special thanks Dr. Louisa Wei, Joe Leung, Ardrian Hardjono (CityU)

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Applied Laboratory of Interactive Visualization and Embodiment

Pure Land is an exemplary new heritage applications by the Applied Laboratory of Interactive Visualization and Embodiment (ALiVE). ALiVE is an interdisciplinary research initiative of the School of Creative Media City University of Hong Kong. Situated at the Hong Kong Science Park, ALiVE is an incubator and innovations showcase for new forms of creativity at the cutting edge of digital media in society. Leveraging technological advances in cinema, games, and mobile, networked and participatory media, ALiVE researches new modes of immersive interactive experience that are of major importance to culture, entertainment, education and industry. Its pioneering infrastructure is made up of unique display environments, production systems and computer graphics techniques. ALiVE builds on creative innovations that have been made over the last ten years at the UNSW iCinema Research Centre, ZKM Centre for Art and Media and at Museum Victoria. Its challenge led research programs act in response to the academic, cultural and industrial opportunities in Hong Kong and Mainland China. This is supported by partnerships with major digital media centers in Europe, USA, Asia and Australia. Examples of other seminal heritage applications recently undertaken include: Rhizome of the Western Han (2010), iJiao (2011), Tripitaka Koreana 360 (2012) and ECloud (2012).

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