Turns out that the virtual crowd work that CIS Vancouver did for Changeling  was just a tune up for the latest Clint Eastwood film, Invictus. The stirring drama about Nelson Mandela (Morgan Freeman) galvanizing a racially divided South Africa through rugby in '95 when he first became president required a virtual crowd game changer by CIS.
"On Changeling, which we did with CIS Vancouver, we did some synthetic crowds, but it wasn't used with the same magnitude that was demanded for on Invictus," suggests Michael Owens, overall visual effects supervisor and long-time Eastwood collaborator. "We went from stage three to stage 20, but it was a good pivot point to handling the demands of the rugby crowd scenes. So, this latest film was both a leap in quality and volume. Technique wise, things have to be reinvented because we'll never get down the road using standard techniques. And CIS jumped on board to do that and pulled it off because it was quite a rework of how you get through that process. And so far the audience response has been that they are unaware that we were there, which is exactly what I was hoping we would see.
"Early on, in reading the script, Clint and Rob Lorenz, producer, asked me how I wanted to do this and, to me, it was super obvious that the only way to get it done was to really approach it in a heavy manner like a virtual world game. You get the players on the grass and everything else is replaced. You give the people their environment so they can feel like they're doing what they're doing and then you wind up replacing it all. I'm sure this was the largest rotoscoped movie of all time."
The only speed bump along the way, according to Owens, was the volume, which escalated into more shots than they had planned in addition to some blood and guts stuff CIS created to lend more authenticity. "They look like warriors and just needed a little help to do that."
To pull this off, CIS realized that the CG people would be viewed closer to camera. As a result, one of the early discussions was how to bring those people to life and make them a part of the emotion going on in the matches. "So we knew that we had to tighten up our character processes, pretty much across the board," explains Geoffrey Hancock, visual effects supervisor for CIS Vancouver. "I had come out of [Changeling] wanting to change the way we did all of our motion capture and this was a good opportunity to rethink that. And that's one of the things I'm most proud of: the people we've created are believable in a screen space that I think is really appealing to filmmakers because you can use it in a broader sense, as opposed to just backgrounds, especially at the volume we were doing with 30,000 people in one venue in one frame at a time all the way up to one person covering a third of the screen height.
"One of the things we've decided about motion capture is that it's very important who you're casting in that role and not to imagine that you really want to be manipulating some of the real groundwork that you capture there, because you want that person to come through. And people are very adept at picking out falseness in humans.
"So we really cross-checked that our digital people matched the motion capture actors that we cast and each character would go through a battery of tests that would ensure that all of the bone segments in our skeleton were laid out and positioned to the same length and joint locations as the corresponding actor. And I think that was an extra step that the motion capture house, House of Moves, provided some new excitement in duplicating people. In the end, we had upwards of 20 physiques that came from these different actors. In past films, we focused on using less people but in a larger variety of ways. But not having to interpolate your animation from, say, a tall, skinny motion capture actor, repurposing it on other body types that don't move and react the same way, was a great benefit. You get different idiosyncrasies, and that was a key.
The system that CIS used between Houdini and Massive was really unique and offered a lot of flexibilities, even late in production. "There's been a pipeline rethinking recently. The whole process is based on Houdini  and Massive  talking to each other and taking advantage of their own strengths. Massive is an excellent motion choreographer. And that's where all of our motion clicks and libraries were created and all of our actions were cached out. But, then, if you really want to have flexibility late in the production and be able to do drastically different animations and layouts of people, Houdini offers that kind of procedural strength. And we wrote a lot of custom portions of our pipeline that got the most out of those two softwares and allowed them to talk together. And all of the other departments started to take advantage of that plug-in to Massive and Houdini. The lighters were now able to have all of their scenes with the people in them, as opposed to importing lights from software to software and having to take multiple guesses at something. It's so much better to be able to see and interact with what you're doing."
For Owens, it was all in keeping with the way Eastwood works. "I keep Clint from having to get into the minutia of it. I love to work cinematically with him on the set and in pre-production and in post. I don't bring technique into the set up -- I just take care of it. And then he doesn't have to delve into that stuff, which can be very tedious. One of the things Clint is great at is giving [everyone] a space to perform in. And so people have to be on their mark when doing their thing, and I think that's a wonderful thing that Clint creates."
Bill Desowitz is senior editor of AWN & VFXWorld.