Issue link: https://digital.copcomm.com/i/799350
www.postmagazine.com 27 POST MARCH 2017 performance and movements. When Ariel transforms into a non-human form, Quartley's movements drive a CG avatar — a digital apparition of Ariel the spirit — that is project- ed somewhere on the stage. "When the avatar appears, Mark can still be seen on the stage as he performs the digital character," explains Lumsden, noting that there doesn't seem to be confusion among the audience, as they tend to look wherever Prospero looks — whether that is at the avatar or Ariel the performer. Ariel assumes two distinct forms (a sea nymph and a bird-like Harpy); in addition, there are hun- dreds of color variations of Ariel and effects, such as him bursting into flames, breaking into particles, and exploding/contracting. The avatars and effects were created by Silvia Bartoli, Brenainn Jordan and Dan Orchard at the Imaginarium. The digital assets were mocked up in Adobe's Photoshop and modeled in Pixologic's ZBrush, then brought into Autodesk's Maya, where they were rigged before they were imported into Autodesk's MotionBuilder for retargeting. That data is then run through Epic's Unreal Engine, where the CGI resides, and output to d3 video servers with Intel Xeon processors. The servers are connected to the RSC lighting desk, which in turn controls the projectors. The digital characters and imagery are projected onto unique screens situated around the theater — sometimes up high, sometimes low to the ground. "The projection of Ariel as an avatar is on every one of them at some point," says Lumsden. "There are also times when he [Mark as Ariel] is on the stage but not projected — there is always a creative logic for the CG to appear, whether it's to tell a story, illus- trate a point or express a strong emotion." For instance, at one point Ariel tells Prospero how he took the form of fire on the sinking ship that forced the magician's rivals to the shores of his island, and shows himself as a flame. In another scene, Prospero goads Ariel, asking if he remem- bers how he freed the spirit servant after the witch Sycorax imprisoned him within a hollow tree. In this amazing scene, a cylindrical cage wraps around Ariel and traps him onstage, while the projection shows him encased within a massive tree structure. A total of 27 projectors and 30 projection screens are used during the production. "The main Ariel projection surface is a system we call 'the cloud,' " explains Lumsden. "There are many viewing angles in the theater, and it becomes complicated when you are talking about projecting a computer graphic. It's not like going to the cinema." The imagery is projected onto a mesh surface that is similar to mosquito netting, which is trans- parent when there are no projections. "It captures light quite well," adds Lumsden. Vicon cameras and tracking technology are used to determine where the screens are, on the stage and around it, so the video server knows where the projections should occur. Vicon's optical camera system also tracks the whereabouts of moving objects on stage, some of which are held by the actors. So, precision is vital. The data processed by the Vicon Tracker soft- ware uses Intel Xeon and Core i7 processors. Without question, the setup — designed and devised by the crew at the RSC — is extremely complex. The group did, in fact, consider having Quartley perform offstage in a capture volume, controlling the avatar projected onstage. "It would have been technically easier, and we would have used an optical system [as opposed to the inertial sys- tem], which gives you more geographic preci- sion," explains Lumsden. "But as Greg [Doran] asked, how do you get that intimate relationship between the two characters, the master and the spirit, Prospero and Ariel? They have to look at each other, and the relationship has to be true and authentic every night. That's hard to do when one of the actors is offstage." Another alternative would have been to use pre-canned animation, but that would not have done justice to the play, either. "[The alternatives] would have been less challenging from a purely motion-capture standpoint," says Lumsden. "But the creative messaging would not have been as strong." MOTION TECHNOLOGY Xsens' inertia motion-capture systems are especially well suited for live performances, since there is no need for cameras and markers, or a preconditioned area. The data can then be streamed in real time into the Epic Unreal Engine 4, as it was in this case. "It gave the RSC the chance to be creative with Ariel's costume by hiding the technology and fo- cusing on its visual appearance," says Beute. "It also gave Mark as Ariel the flexibility to move around the stage without technical limitations." As Beute points out, motion capture is typically a one-off shoot: You plan a shoot, capture the move- ments, and you are done. Taking motion capture to the theater means the technology needed to be robust and reliable enough to sustain several plays, or shoots, a week. It's worth noting that despite the cutting-edge nature of this application, the RSC used an off-the-shelf Xsens system with the latest MVN Studio software. While Lumsden cites the overall project as the biggest challenge, he is quick to point out that the realtime facial-capture technology for this applica- tion proved especially difficult. "We created our own realtime setup for the show, and it was really chal- lenging to get that working. It's proprietary software we wrote, but now it will be part of future projects we do at the Imaginarium," he says. While there are some commercial options avail- A CG model of Ariel (above left) was used for the projection showing the character trapped within a tree (above right).