Postcard from GDC 2005: Normal and Displacement Map, Sitting in a Tree

Factor 5 designer Matthias Worch began Wednesday morning with a brief lecture on asset creation for next-generation games; his focus was on the distinctions between full-on digital and maquette models, as newer technology has come to make older techniques seem attractive. Before Worch began, however, he already had two problems. One was that, as his next-gen projects have yet to even be announced, he was unable to use his own material in the demonstration. The other problem was that his lecture began twenty-five minutes later than scheduled; to well use what time he had, Worch skipped straight to the demonstration.

That demonstration focused, largely, on a large ogre-like creature named "Leon," built as a maquette and digitally captured using an Cyberware M15 proprietary scanner. Worch also discussed the XYZ scanner, top-of-the-line hardware used in Peter Jackson's Return of the King and Kong films, and showed scans of people's heads, zooming into the models until their pores and the tiny hairs on their faces were visible. For normal use, however, Worch advised that a Cyberware M15 is sufficient; current color maps are of too low a resolution to show pores, anyway.

Worch spent much of the lecture loading Leon 's model into his favorite applications, and demonstrating the possibilities they allowed him. Of particular note is CySlice, which has tools to resurface enormously detailed models - as you might get from a digital scan - while retaining much of the original model's profile. Leon 's scan, for instance, has three million polygons; Worch commented that CySlice is one of the few programs he knows of that can handle a model of this size: "If you want to load it in Maya, it'll take about three hours. I don't know what they're doing with the .obj code, but it's pretty ass." Worch also demonstrated a tool to automatically extract normal, displacement, and color maps from the original model, allowing for even closer approximation.

For contrast, Worch spent his last few minutes exhibiting a pure digital model - one of similar quality to Leon - in ZBrush, using "blobbing" tools to deform the model, and a 3D paintbrush to add organic-feeling lumps to a protruding tusk. He compared the program to Deep Paint, an old favorite of his.

Almost all developers Worch has talked to, he said, have dismissed maquettes; they reply that the data maquettes provide is too irregular, and must be corrected by hand. With the amount of time and effort that takes, developers feel they might as well just make the models from scratch. As Worch showed, however, the tools exist to manage maquettes with a minimum of trouble. Are maquettes worth it, then? When done correctly, Worch explained, their cost equals that of digital models - and there are further benefits. For one, they provide a practical reference; the whole team can "look, touch, snuggle" the models. These same models also provide good PR opportunities (provided you cast and save the original model before cutting it up for scanning). Further, although a good digital modeler can be hard to come by, there is a surplus of expert maquette artists, trained for film and working less and less these days, waiting to do the work for you. The choice, Worch implies, is up to you. Know, however, that you do have a choice.

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