Computer Graphics World

n n n n 3D Printing•Architecture terms of the information and context such models could provide. Nevertheless, creating the three-part World Trade Center Triptych was not without its challenges. Building a Dream Munson began the endeavor a few years ago, after meeting the person who runs the 3D printing shop at the Port Authority in New York City. After some discussion, he discov- ered that the Port Authority uses white mod- David Munson (left) stands next to the 3D printed models he made of the World Trade Center. The triptych accurately depicts the area at three stages: before and immediately after 9/11, and today. Munson donated the models to the New York City Fire Museum. At right is Damon Campagna, the museum's director and curator. els, not colored ones. "What makes me a little different from many others in the field is that I apply color taken from texture maps used in the visualizations," Munson explains. "My physical models are physical instances of vir- tual models that are done first." According to Munson, the man appeared The color printer accurately matches the texture maps Munson used in the computer visualizations that he created first. 50 October/November 2011 interested in seeing this kind of color map- ping on 3D printed models, so Munson decided to re-create the area around the Twin Towers, "as the way we all remember them," hoping the Port Authority would hire him to do a simi- lar model of the new site. He didn't get the job, but the effort got him thinking: He could extract 3D data from 2D sources, par- ticularly photographs and LIDAR and sat- ellite imagery of the site, to depict the area at a different point in time—the time of the destruction. "I was working on another project where I was doing this same process and thought, technically, I could do it fairly quickly [for the World Trade Center] because I have the context," Munson recalls. "I thought having the two models would be interesting." Emotions, though, started to weigh on him. "It was a bit too depressing," Munson says of the before and after models. "I needed to have a third one, of the new site, to shine some light on the situation." Munson began the World Trade Center project nearly two years ago, working on it in his spare time. After investing countless hours, he was determined to finish it, hoping that the hard work would pay off in terms of gain- ing him, and his techniques, exposure. "This is a new medium," says Munson of using the texture maps from the digital replica for the 3D print used in urban-scale visualization and planning. "It's difficult to get institutions and decision makers to get on board without some kind of precedent. Architects are creative de- sign types, but they can be conservative, too."

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