Computer Graphics World

July 2009 61 Gaming n n n n Norton, there were more than 30,000 books in the library. "ere are no tricks here; they are individual books. ey're persistent, too. If you want to spend the time shooting shelves, you can empty them all and push all the books into a giant pile," he says. "I've done it myself a few times." e game's most interesting villains— and the more unorthodox character ani- mations you'll find in the game—are the golems: shapeless entities whose form slowly coalesces as they draw books, coals, and anything else around them into their midst. "When we first discussed the idea of golems, we were going to use the tradition- al method of creating them from the 3D geometry and rigging them like a normal character," says Norton. "But then, we all agreed to push the envelope a bit." e team devised a method of putting tags along the golems' joints in Maya. e Infernal Engine would then make objects that surround the golem jump up and at- tach themselves to those tags. "e first test was a book golem. Everyone was excited to see how a character could form right before their eyes. We immediately started creating golems that had some interesting silhou- ettes," says Norton. For the kitchen golem, who chases the ghostbusters through the Sedgwick Hotel, the artists assembled all his kitchen-related parts beforehand so they could choose the best silhouette for him. Once that was approved, they placed each part it in the kitchen, where it is usu- ally found. When the character appears, each one of those parts levi- tates and attaches itself to the correct tag. To make chandeliers and other luminescent objects glow realisti- cally, the team mapped them with an emissive material in Infernal. For moving, incandescent entities, such as the coal golems, the artists first applied an emis- sive material in Infernal, and then added a dynamic light that moved around the set with the character, giving the effect that they are casting light onto nearby objects. Artists developed the translucent ap- pearance of Slimer, the fisherman, and the other ghostly entities with a mix of transparency maps and emissive materials created in Infernal. "e ghosts actually have very little diffuse [shading] applied to them. We wanted to control how much light they received from the environments, so we ended up isolating them from the environment altogether," explains Norton. e artists ended up applying a custom lighting and particle solution to each ghost to help them resemble their movie prede- cessors. ey also added volumetric light- ing and particle effects to light fixtures and skylights in the mu- seum, for example, to create atmospher- ic cones of light. When Venkman is bowled over and slimed in the Sedg- wick, artists used lots of particles and materials, all created in Infernal, for the lime-green slime. "Basically, the alpha [channel] of the par- ticle acts as a mask for the flowing 'liquid' underneath," says Gamble. To create the liquid, the team used CrazyBump (avail- able via the Web) to create animated nor- mal maps of ooze running down his face and body. High Spirits Atari's divine intervention last year proved timely for a couple of reasons. It delayed the game by seven months, giving Sony and the entire development team a long grace period in which to polish the game. And, coincidentally, it also aligned its release with the film's 25 th anniversary. "Typically, you start off a project thinking you'll use the last three months to polish, but along the way, more features are added, massive changes or overruns occur, and that time is lost," says Norton. "In this case, the art was all to a point where it could have shipped at the original release date. But when we got the extra time, Atari and Terminal Reality were smart in that we avoided adding new con- tent. We just made what was there better." Now, only time will tell if Atari will be rewarded for its faith and if Terminal Re- ality will recapture and contain the spirit of the ghostbusters, and preserve it for a whole new generation … at least until the new movie arrives in 2012. n Martin McEachern is an award-winning writer and contributing editor for Computer Graphics World. He can be reached at martinmceachern@hotmail.com. Infernal's dynamic cloth sim drove the garments worn by the Female Possessor. The character Slimer, with its squashed and stretched look, appears in the game. The model also has a custom facial rig with more than 10 Maya controllers in its mouth alone.

• Cover