Keeping It Real
Karen Moltenbrey
February 4, 2011

Keeping It Real

When it came to creating the new MMA title at Electronic Arts, there was one clear goal: authenticity.
When it came to creating the new MMA title at Electronic Arts, there was one clear goal: authenticity. The animators did their part by spending the past six to 12 months of the production giving characters their signature moves, ensuring that each fighter acted and reacted realistically during the matches. The modelers and artists did their job, too, creating an array of top fighters who accurately resembled their real-life counterparts, and building venues that had the familiar look and feel of popular fighting arenas from around the world.

“We wanted all the fighters to feel like themselves and fight like themselves,” says Simon Sherr, animation director.

The game features more than 60 well-known fighters from the sport of mixed martial arts, including Randy Couture, Fedor Emelianenko, Hidehiko Yoshida, Ken Shamrock, and Ronaldo “Jacare” Souza, among others. To build these characters, the EA Tiburon group started with photographic reference obtained in a controlled environment, where the necessary facial structure and texture maps, among other things, were captured.

The ultimate fighters were modeled using Autodesk’s Maya and Pixologic’s ZBrush, and surfaced with the photographic textures. “We level out all the values from the bit-map chart so we get a nice consistent tone across all our textures, then we lift our texture maps off those flat-lit images,” explains Gerald Phaneuf, associate art director.

Separate teams constructed the various CG heads and bodies for MMA’s fighters. A third group, the skin shading team, handled all the skin tones independent of the heads and bodies. A lighting team then lit the characters and venues.

“We have shaders that accommodate a lot of the materials and lighting techniques we wanted for the characters,” says Phaneuf. “There are many complicated layers of textures that we separated and recombined in the game to get our end results.” Skin, shown prominently in the game, was one of the more complicated textures, and the team spent a good amount of time making it look as realistic as possible.

One important part of the character creation process, says Phaneuf, is controlling the fundamental assets. To this end, the crew uses a Macbeth Chart, a common photography tool, when capturing the texture assets for the characters. “This helps us maintain predictability and keep consistency across all our textures,” he says.

The character lighting/shading model included direct dynamic lighting, self-casting shadows, subsurface scattering for the skin, SSAO (screen-space ambient occlusion), a Kelemen-based specular model, specular cube lookup, and hemispherical ambient lighting, among other ancillary features. “It was quite complicated and, at times, cumbersome to tune, but it offers some powerful features that allowed us to blaze a few real-time character rendering trails,” says Phaneuf.

The specular model, in particular, was multi-faceted. “We used textures to define eccentricity, intensity, and occlusion of specular/reflected light,” Phaneuf explains. “This separation of specular aspects allowed us to define oily versus dry parts of the skin, as well as enhance the effect of sweat.” The team has approximately a dozen texture channels that are fed into the skin material, contributing to its result. “Skin was a focus for us on this project; the headway we made not only benefited us visually in this product, but laid the groundwork for expansion in future products,” says Phaneuf.

In addition to the pro fighters, players can create their own unique competitor and bring him up through the ranks. Using the photo game-face tool, players can automatically generate fighters in their own likeness. The tool maps key points on photographs (displaying a front and side view), and then generates a matching head containing the person’s facial texture. It also matches the mesh of the facial skin tone on an accompanying CG body.

The game also features a number of effects, one of which involves blood. The EA team developed a system that builds up damage over time, so if a cut develops, it will start to drip blood and, eventually, the blood will trickle down the fighter’s face. Furthermore, the system will detect that there is blood on the face, and when the opponent’s hand hits the person’s bloodied face, it transfers a subsequent bloodstain when contact is made with other areas of the body. There is also universal transfer of this damage into the environment through a persistent blood system, whereby blood particles will stay on the mat throughout the duration of the fight.

Many of the game’s venues, meanwhile, are replications of actual locales, re-created from photographs—the Strikeforce venues, for instance. Others are the creative vision of the artists, including some of the international locations. “The gym in Thailand is based on the vision and research of what we wanted it to feel like because we did not have a specific gym there to duplicate,” says Simon Sherr, animation director. The various arenas include boxing rings, circular cages, and hexagonal cages.

With such attention to detail, EA Tiburon delivers a realistic fighting experience that can only be topped by stepping into an actual arena.

Karen Moltenbrey is the chief editor of Computer Graphics World.

For a detailed look at the complex animation and other challenges faced by the EA team, see the cover story “Contact Sport” in the January/February 2011 issue of CGW.