The making of Transformers 2
23rd Jul 2009 | 09:00
How ILM and Digital Domain pushed CGI to the limits
Building the Transformers
Could Sam Witwicky (Shia LaBeouf) really go off to college and leave the very hot Mikaela Banes (Megan Fox) and Bumblebee, his giant robot friend and protector, behind? He really tries, despite Mikaela's obvious charms, and even though Bumblebee cries windshield-washer tears.
But director Michael Bay has something else in mind to distract Sam from his studies: robots. Scores of robots. Big, brutal transforming warriors and nasty, clever little helpers – and they're all out for Sam's blood. Yes, it's Transformers 2, otherwise known as Transformers: Revenge of the Fallen – and the effects are bigger and bolder than ever.
For 2007's Transformers, which raked in more than $700 million at the box office, lead VFX studio Industrial Light & Magic turned the cool little 1980s Hasbro toys into 14 bone-crushing giants that crashed through the streets of Los Angeles, smashing buildings and each other in over-the-top, rock-hard action sequences. But that was just a warm-up for Revenge of the Fallen.
The sequel blasts your eyes with thousands of hard metal parts, spinning and sliding gears, wheels, crankshafts, pistons and headlamps as nearly 60 jaw-dropping robots take their battle to seven states, three countries, and one alien planet. Add in another 40 CG vehicles, and the total count is more than 100 major 3D assets.
Massing the troops
As before, ILM took the lead in the effects work, creating both the lion's share of the robots – 45 in total – and the largest and most complex machines. The studio created all of the heroic Autobots, including their returning leader, Optimus Prime; and many of the evil Decepticons, including both Megatron – seemingly destroyed at the end of the first movie – and the megamonster Devastator, who is five times the size of Optimus Prime.
"The locations, the effects, the style are all huge," says ILM's Scott Farrar, who reprises his role of VFX supervisor from the original movie. Rendering shots for Transformers took between 16 and 20 terabytes of disk space in the studio's renderfarm. Transformers: Revenge of the Fallen took 140 terabytes. "The amount of render time is colossal," Farrar says. "The whole movie is that way."
Bay's own studio, Digital Domain, created 13 Decepticons, ranging in size from little ball-bearing 'microcons' that transform into a razor-bladed creature called Reedman to the enormous Soundwave, which links up to communications satellites. Digital Domain also created Wheelie, a rascally little bot transformed from a remote control vehicle, and Alice, the 'pretender' who transforms from a human seductress.
Such human qualities are one of the most significant ways in which the robots in Revenge of the Fallen differ from those of their predecessors. "People will be amazed at the interaction of the robots with the environment," Farrar says. "They kick up dirt. They interact with trees. And they sweat, spit, drip, and squirt fluids like blood." The fluids, which help give the robots a more organic feel, were added almost as an afterthought.
For a shot in which Starscream, one of the returning Decepticons, has to react to Sam, ILM was tasked with finding ways to make the interaction more dramatic. The solution was simple, but crucial: "We decided to have Starscream spit at Sam," says associate visual effects supervisor Jeff White. The effect worked so well that the animators began looking for more opportunities to have the robots dispense water, sparks, gas and smoke.
This more organic approach carried over into the design of the Transformers themselves. The robots' faces have been given significantly more human characteristics, enabling them to act, emote and talk. In total, 40 of the robots have at least one line of dialogue.
"In the last movie, a small number of robots had a couple of lines," says animation director Scott Benza. "This time, there is a lot more dialogue; and a lot more important dialogue to help carry the story." With little more than a year to complete the effects, ILM significantly increased the size of the animation team to cope with the increased scope of the project. "We had fewer than 20 animators on the first film," says Benza. "This time, we had over 50 because we had so many more robots, and three times the complexity of the work."
Matching jobs to skills
With animators often facing complicated 500-frame shots with three robots, Benza cast his staff according to their skill sets. "Some animators were interested in animating particular scenes, so I'd shift things around to give them a chance to do those shots," he says. "Specialists in animal behaviour would get the Ravage shots because he was a cat-based Decepticon. Others were specialists in dialogue and acting performances."
To create these performances, team members were aided by a rigging system developed by ILM for the previous movie, through which they could choose what parts of the model to connect. "An animator can animate any individual part or any groups of parts," Benza says. In addition, a new system provided the animators with a little procedural help on the more complex shots.
"The creature development team gave us the flexibility to put the robots into any pose and not have interpenetrations in adjoining areas," Benza says. "With so many moving parts, it's quite a task to make sure every individual part doesn't collide with its neighbours."
But even with the rigging system to call upon, the first pass at preventing penetrations was carried out by hand – and with Benza, normally in charge of procedural animation, busy in a supervisory role – there were no shortcuts for final-quality animation, either. For example, the Decepticon Scorponok, which was procedurally animated on the original movie, is now entirely keyframed.
A question of scale
A question of scale
The scale of the task ILM's animation team faced on Revenge of the Fallen becomes even more apparent when you consider the movie's showpiece scenes: the transformations of the robots from one form to another.
The biggest transformation is unlike any seen in the previous film, and it's for the biggest Decepticon ever. Standing 100 feet tall, the Devastator has 13 million polygons and 52,632 parts. Moreover, he's formed out of six separate robots.
"The idea we came up with was that the Devastator forms in a violent fashion," Benza says. "We rooted his transformation in the biggest Constructicon." The 'Constructicon' in question, Scavenger – a big red mining excavator – transforms first, then smashes itself into one construction vehicle after another, each transforming and connecting to the previous bots to form the giant monster. His head is all mouth: a cement mixer. It's a tremendously dramatic scene, and the effects are awe-inspiring.
To make matters more complex, Devastator is so big and has so many parts that the animation crew couldn't treat him as a single asset. "When we tried to load the entire model in high res, it would grind the machines to a halt," Benza says. "We had two machines fail trying to work with him. One literally smoked. We don't know for sure if it was a direct result of working with this character, but it certainly did get overloaded – and fried."
The scene of Devastator forming was completed in 4K resolution for IMAX screens. The scale of the work forced the crew to develop a set of tools that enabled the animators to work in layers of complexity. "We had seven choices for resolution," says digital production supervisor Jason Smith.
Options for the level of detail at which each part of the model was displayed ranged from proxy geometry and 25K resolution at the low end to 1,300K resolution at the high end. "To control the system, animators had what we called 'Mr Potatohead buttons'," says Smith. "They could select any part. For example, they could set Devastator's arm at 25K resolution, and his head at 31K."
While the level of detail system speeded up the animation work, when it came to final output, truly massive rendering power was still required. In one of the film's biggest scenes, Devastator climbs a pyramid in Egypt and once at the top, begins ripping the massive structure apart. For this shot, which was also at 4K resolution, ILM used a fluid simulation to move the sand and a rigid body simulation to break the pyramid into millions of blocks.
"Some frames would have taken 72 hours to run on a single processor," Smith says. "We used multiprocessors – 26 processors – to chew through the work faster." But for all of the new technology ILM developed for Revenge of the Fallen, not to mention the complexities of wrestling with IMAX resolution for several shots, the studio describes the key innovations of the movie as creative, not technical.
First, the VFX supervisor and animation director shot plates on location and provided guides for the film's editors. For a three-minute fight scene set in a forest between Optimus Prime and several Decepticons, Farrar and Benza ended up supervising the plate photography, and took first cut at editing the footage. "We don't typically get involved with editorial decisions," Benza says. "But because we shot the material and knew what the plates were intended for, we took a first pass at putting the forest back together as a template for the editors."
Second, the animators contributed dialogue and choreographed two key fight scenes in the movie: both the forest battle and a sequence in which Bumblebee literally tears Rampage apart, giving a little satisfied nod of the head after he has decapitated the Decepticon.
"We designed the first version of the fight not knowing how it would be used in the movie, with Bumblebee and the cop car robot from the first movie, Barricade," says Benza. "Michael Bay liked how tight the edit was and the brutality when Bumblebee tears the limbs off, so he found a place for the fight in the movie and substituted a different robot."
And finally, the director 'shot' scenes directly on ILM's motion-capture stage, working in collaboration with the animators. "We blocked out the scenes, loaded them up on our stage, and put a virtual camera into Michael's hands," Benza says. "On the set, you often see Michael behind the camera, so we wanted to give him a hands-on experience for the digital scenes."
MAKE YOUR OWN:Follow 3D World's video walkthrough to turn a train into a 'Trainsformer [Image credit: 3D World Magazine 2009] Video walkthrough
The resulting movie is an enormous human achievement, not only considering the vast scale of the work undertaken, but also for the way in which ILM's staff became involved in tasks traditionally thought to lie outside the control of visual effects artists.
The crew considers Transformers: Revenge of the Fallen as one of the most collaborative films they have worked on. As visual effects steadily become a part of the production as well as the post-production process, it only remains to be seen where Industrial Light & Magic's increasing level of creative control will take the studio – and the movies it works on – next.
Industrial Light & Magic received an Oscar nomination for creating the 14 mechanical stars of the first Transformers movie. For the sequel, 3D World magazine discovered how the studio built, rigged and animated not 14 robots, but 45.
But ILM doesn't just build Transformers. Its innovations have transformed the entire 3D industry, so 3D World took the time to talk to key studio staff about how the studio have continued to stay on top after 34 years of technical breakthroughs.
3D World's coverage of Transformers 2 and ILM can be read in issue 119 of 3D World out now.