Digging for Details
Issue: Volume: 30 Issue: 8 (Aug 2007)

Digging for Details

Painstaking research results in a brilliant 3D re-creation of Mayan ruins
By Rachael Taggart

Was the layout of ancient Maya cities meticulously planned, or did it occur haphazardly? Did religious beliefs influence the design? Helping to shed light on these and other questions is Clement Valla, an architectural designer by profession and a 3D freelance modeler by choice, whose 3D imagery painted the necessary picture that enabled archaeologists and others to more accurately formulate their theories about the cities.
Valla was given the opportunity to record, reconstruct, and then create a documentary about a 1000-year-old Maya city. After more than a year of planning, traveling, and working on the project, he produced a series of video documentaries that show the reconstructed city and try to resolve a number of theories about city planning at the ancient site.

PAPAC, or Proyecto Arqueologico para la Planificacion de la Antigua Copan, is based at the UNESCO World Heritage ruins in the Copan River Valley in western Honduras. Regarded as one of the most important Maya ruins, the city was abandoned in the early 10th century after many hundreds of years of habitation. In 2005, the Department of Anthropology and Sociology at Colgate University (New York), in partnership with PAPAC and sponsored by the Honduran Ministry of Culture, started a project to determine if intentional city planning was a part of the growth of Maya cities. The archaeological team also wanted to investigate a hunch that the city planning was influenced by sociopolitical and religious ideas, especially those centered on Maya kingship.

This meant the group would have to reconstruct parts of the city and the valley landscape based on archaeological findings. And to achieve that, the project team needed 3D digital technology and expertise, which Valla provided.

On-site Surveys

While planning for the project started in 2005, Valla’s work really started when he visited the ruins in February 2006. “For the first part of the project, I was working with information from a completed dig,” says Valla. “This meant the excavations had already been covered back up for conservation purposes. So I had to work with hand-drawn plans and maps, and was able to generate some GIS data on-site for referencing.”
Valla then digitally scanned several hundred hand-drawn plans of the dig, and imported them into Rhinoceros, 3D NURBS modeling software from Robert McNeel & Associates. This enabled him to arrange the 2D scans into 3D layers, thereby creating a set of working reference points for constructing a 3D model. The GIS data that Valla had recorded likewise was imported directly into the 3D software, allowing him to scale the model and produce accurate topological models directly in the software.

“Arranging all this disparate data in Rhino was easy,” says Valla. “Once the data was in, I could reconstruct the ruins in 3D. That’s when the interesting aspects started—reconstructing the buildings as they were 1000 years ago.”

Using extremely detailed notes, the archaeological team and Valla extrapolated what each structure would have looked like long ago. “The level of detail from the archaeologists is amazing,” he says. “Even the most minute details, based on the tiniest of findings like a roof feature, gave these experts the clues to determine what kind of roof structure was used, how high the building was built, and so on. I would then reconstruct that in the model.”

The second part of the project occurred on a current dig within a different area of the ancient city, where Valla visited again in March 2006. The ability to survey and record visible ruins brought up more options for Valla to create rapid and accurate 3D data for the model; he opted to use photogrammetry software that would allow the fast creation of 3D data from photos. Valla selected PhotoModeler from Eos Software “because the performance was high and the cost suited our budget.” Using a Nikon SLR camera, Valla took detailed photos of the open trenches and ruins to record the details.

This reconstruction of the discovered tomb under the ruins, in crosssection, was created using photogrammetry and 3D modeling.

“While we were there, an incredible tomb was discovered, and taking photos allowed us to record exactly how it looked when it was opened as well as gave us usable data for creating the 3D model,” says Valla.

PhotoModeler works by using scans of photos to determine a series of 3D reference points, which can then be imported into 3D CAD systems for a variety of applications, including reconstruction of events or scenes. “With the photogrammetry, we could take away photos and come out with a very precise 3D data model,” says Valla. “We then imported the information directly into Rhino, where we could work on the 3D model, render it, and animate it.”

The tomb apparently was in danger of caving in when it was discovered, so the team recorded exactly how it looked before performing the construction work that would ensure the safety of the archaeologists as they entered the tomb. “The tomb was well below the ground and about 3x2x2 meters in volume, which made photography quite challenging, but really the only option,” says Valla. Moreover, the challenges of the vault were numerous—the team could not risk touching the walls, as the plaster would fall off. In addition, lighting was poor, given a weak power source. Finally, Valla, with a personal fear of spiders, faced his own fears as he entered the tomb.

Above shows the original 3D wire-frame reconstruction of the ruins prior to being re-created in 3D solids for the video work

“I was apprehensive about going into the vault, for all the reasons above—not just the fearsome spiders in Honduras, but the fact that we were only there for a week and needed to record as much data as possible,” Valla says. “The resulting model used about 60 photos of the tomb and turned out to be highly accurate and a superb recording of the artifact.”

The Past Comes to Life

After Valla turned all the data into 3D and performed the reconstruction work in Rhino, he exported the model into Autodesk’s 3ds Max, where it was animated and rendered. This past February, he again returned to the area to acquire more digital information. The animations are the basis of the documentary work, which will be finished this year.

Professor Allan Maca, an archaeologist from Colgate University and director of the PAPAC project, commented that the benefits of the 3D reconstructions are multiple, and had high praise for Valla’s contribution. “There are many ways that Clement’s work helped—too many to discuss in detail. For instance, the reconstruction of the ‘hypothetical’ city is highly detailed and quite true to form. We can now see the city in ways that were otherwise impossible with 2D scale drawings, which heightens our understanding and knowledge, now allowing us to test other hypotheses on the ruins.”

Maca adds that the reconstructions go beyond science to an educational level, allowing him to teach students and colleagues about the goals and results of the projects. Maca points out that Valla’s work on various projects has already been used to directly teach the Honduran government and public about the importance of ruins located on private lands and the need to protect the sites from looting. In fact, the team is working on securing government protection for ruins that they see as endangered by using the 3D models.

“Finally, Clement’s work, based on multiple sources of data, raised the team members’ awareness of the importance of the data they produce,” Maca points out. “Clement’s focus on detail helped bring us together as a close-knit team, whereby each of us realized the importance of every aspect of our work and how it could be used by Clement later.”

Maca described the painstaking level of detail and research that Valla engaged in. “Clement’s work is both accurate and provocative, but is the result of months of reading and research that Clement himself did, as well as the close work with myself and the rest of the team, to be able to understand the intricacies of Maya architecture. As a result, the 3D reconstruction is accurate and allows us to develop our thinking in ways we never thought possible. We hope this is an experience we will repeat with Clement as the project continues.”

Having spent years working on architectural 3D models, renderings for presentations, and more, Valla found this project to be “entirely consuming, validating, and satisfying,” he says. “But I could not have done this project in just any software,” he adds. “Rhino was versatile in its 3D commands and became the glue that tied all this disparate data together into a usable model for the investigation.”

The PAPAC project, funded by National Geographic and Colgate, can be seen at www.papacweb.org. The subsequent documentary, titled Kuhul Copan Ajaw, is expected to be used as a part of the archaeological program at Colgate as well as a key part of negotiations with a cable channel to air the series.  

Rachael Taggart has been an industry writer for more than 15 years in the CAD, AEC, and PLM fields. She is based in Denver.