Building The World of Hercules
COW Library : TV & Movie Appreciation : Tim Wilson : Building The World of Hercules
And so we come to the time that $100 million is considered a moderate budget for a large-scale epic. This was the production for Hercules, but compare that to the $250 million for The Chronicles of Narnia: Prince Caspian, or even the $170 million budgets for Guardians of the Galaxy and Dawn of The Planet of The Apes. One way that MGM/Paramount's Hercules, directed by Brett Ratner and starring Dwayne "The Rock" Johnson, manages to look as large as it does on its relatively modest budget is through careful and clever use of CG that doesn't look like CG.
Needless to say, one of the key special effects in the movie is Mr. Johnson himself. His first major features were the sword and sandals epics The Mummy Returns and The Scorpion King, both of which fared very well in the US, but didn't even begin to reach the international audience that he now commands. Along the way, The Rock has also added a strong comic dimension to his onscreen action persona, and Hercules offers the opportunity for him to combine them, as well as appeal to his now global fanbase.
Make no mistake. There are plenty of CG creatures in Hercules, but some of the most compelling effects in Hercules are in the family of what's increasingly commonly called "invisible effects." At its most simple, these might include sky replacements, although as the VFX team at Method Studios discovered, those are anything but simple when there are hundreds of elements in the scene that need to be roto'd first, and scenes that need relighting as the sky changes.
On a more complex level, the CG in Hercules was used by Milk VFX to create entire environments, including the city of Athens and the collection of elaborate buildings atop the Acropolis, including the Parthenon -- but also the surrounding hills, shore, and sea.
Together, Method Studios and Milk VFX are two of the companies that helped create a full, realistic world for Hercules, from the sky, to the Acropolis, to the sea.
METHOD: THE SKY, FIRE & DESTRUCTION
Method's Doug Bloom started on the production of Hercules as the film's Digital Supervisor. A couple of weeks in, Method needed to reallocate their resources across projects, and Doug moved up to Visual Effects Supervisor, his first time in that role.
One of the challenges is that Method was almost simultaneously doing R&D for the technology they were using to build the effects, building the effects, and working with other houses on many of the same shots. "It was a logistical challenge, trying to sort everything out," Doug says. "The things that needed to be built, and needed to be developed, or that already been through a couple of iterations, versus the things that hadn't been really explored at that point yet."
"The majority of the sequences were actually shot at night," Doug continues, with the darker look actually giving the creative team more latitude for dialing in the right amount of light in the grade, primarily to establish more a dusk look. Most of the shots weren't green screened, meaning a lot of roto and tracking. It also meant a lot of work to balance skies, clouds, plate photography, CG building extensions, and VFX to avoid having any of it look pasted in.
Final shot by Method Studios
"It's a big challenge because in the original photography, the shadows are black, because there's no real full light out there. So you don't have any of the blue-ish kind of feel that you get from a day shoot. So we went back and forth with them a couple of times just to see how comfortable they were with adjusting the original plate photography. Even when we put a sky in there, it may have looked like a beautiful daylit sky, and then we added our CG set extension in the same lighting, but the actors in the original set pieces still felt like a little like cut outs. So we did a bunch of iterations where we started to push a little bit of the blue into the foreground photography.
"When we got a look that the client was happy with, we saved that and made sure our background and CG elements all worked with that, but we didn't actually modify any of the original photography on our end. We ended up providing mattes for the DI house, which was our sister company, Company 3. This allowed them to isolate the foreground photography from our skies, and sometimes even a mid-ground element, so that when they were in the DI they had a little bit more control."
Method's biggest components to create themselves were destruction and fire. While there was some practical fire on set to provide a guide, the challenge is still to figure out what the creative team means by "fire." How big is it? How fast does it move? What does it actually look like?
"The challenge was just to put the time into developing the tools and the methodology doing the work, while still producing shots on a daily basis," says Doug. "We wanted to keep iterations coming, and keep the conversation moving in terms of how big should these fires be, how fast should they be moving, or how much of this building should be destroyed at this point in the sequence."
Original plate. Most of Method's shots were filmed at night, which gave the creative team more latitude for dialing in the right amount of light in the grade.
Final shot by Method.
Method wound up splitting the team to work on some of the most difficult shots even before development of the tools to actually do the work was complete. "Around halfway through the show" -- which was approximately four months for Method -- "we got to the point where we could turn around an iteration in 24 hours.
"But that was assuming we knew the exact control that needed to be tweaked. If it was a matter of make it two times faster, that was a pretty understandable control that the artist had. In the case of wanting to introduce a new component that wasn't in the fire in previous versions, that could be a two or three-day turnaround to include doing some tests and iterating through and then eventually getting a new comp out."
In the end, Method worked on around 170 shots, about half of which were mostly or entirely CG. "We were actually pretty happy with the way the elements held up as they started modifying the exposure and pushing things around quite a bit. It's a single battle, but there are multiple stages within it. It's got a really nice pacing where it builds up and there's a big event, and then it settles for a moment and then builds up faster, and there's a big event and then it happens one last time -- and we're very happy with the work and how it turned out."
MILK: ATHENS, THE ACROPOLIS AND THE GORE TOOL
London-based Milk VFX worked on Hercules for eleven months in all: eight months for R&D and building assets, with eight overlapping months for creating and delivering 88 shots.
"The biggest part of our work was to create a full CG environment of Athens, featuring the Acropolis," says Nicolas Hernandez, Milk's VFX Supervisor for Hercules. By the time they created the famed hill above the city with such notable buildings as the Parthenon and Athena's temple, as well as a full amphitheater, the city, the shore and out to sea, it was a full 9 kilometers of fully CG environment, ready to be flown through at any resolution the filmmakers wanted.
"We approached the challenge as creating a massive master asset, with the terrain, the mountains, and the Acropolis, to get the geometry sorted. We started with Google Maps of Athens and also referenced ancient maps for the terrain and scale, and ideas for how we should lay out the main street," says Nicolas. "For example, there was a lot of going back and forth to get the back mountains to look big enough in one shot, but not too big in another."
One of Milk's signature shots was the flyover of the Acropolis in Athens.
While this was going on, part of the team of 35 was working on standalone assets: 10,000 houses, 10,000 trees, 1200 market stalls, 250 boats, 45 different buildings -- and for one scene, as many as 15,000 people filling an amphitheater, each with props and costumes, and a variety of movement. In the past, crowd-simulation software such as Massive was very technical, well outside the main pathway of the actual effects creation, and very render-intensive as it creates crowds as individual elements. Instead, Milk worked with the developers of Golaem, which works directly inside Maya, and based on particle systems.
As for Athens and its environments as a whole, Milk created it all to be as flexible as possible. When opening that massive landscape, nothing was loaded. All of the assets were loaded in a library and cached, ready to be added to the scene as desired. Because they were cached, they were immediately available for real-time flyovers, even though the scene as a whole contained billions of polygons.
"Usually you create geometry and paint on top of it with a projection, but we wanted to have individual elements that we could add as we needed them -- almost like Legos," Nicolas says. "Once we learned the scale of the environment or a single shot, we could add them without having to create an entirely new geometry and mapping for the entire massive scene from scratch."
Their preparation work also allowed real-time adjustments to detail. A flyover allowed low-res versions of buildings, but coming in closer of course required much higher resolutions. "We created all of the assets with different levels of geometry and texture. For example, every one of the 10,000 trees had 1 million polygons, with every leaf modeled," says Nicolas.
"All the textures were done using procedural maps for the surfaces: marble, terra cotta, grass, concrete -- everything. All the shaders had the physically correct attributes, like the marble's reflectivity." Because it was procedural -- that is, derived from mathematically-generated tiles, rather than specifically projected skins that would need to be re-created individually -- the amount of detail could be dialed in in real time.
That even extended to dirt. "The Acropolis had to look really clean," says Nicolas, "but when we needed to add dirt, we were able to do that procedurally as well."
THE GORE TOOL
Milk VFX CEO Will Cohen pointed out that these kinds of approaches are very adaptable. "Everything you develop in one movie, every way you evolve, you carry through to the next. During the course of Hercules, when it was originally a gorefest, we developed something called a Gore Tool."
As Nicolas explains, "This allows any kind of source -- say, a sword -- to meet a target on the body, it can generate any kind of fluids, blood spurts, wounds -- it's very realistic. We developed it in parallel with our other work because a lot of shots needed gore enhancement. As these things go, the film became PG-13, but the gore is applied as a matte, sort of like a pass, and could be easily adjusted. If we needed to change the amount of gore, that was the only part of the scene that needed re-rendering.
"In compositing, we could easily adjust it. For instance, we had a shot with a prosthetic head on a spike. The brief was to create a realistic crow in the center of the frame, picking an eyeball out of the corpse, and squeezing the eye juice out," he laughs. "It's fun to do.
As a child, Hercules had killed two snakes which had emerged from the eyes of a statue of Hera. Above, Milk's CG snakes and statue.
"We spent a lot of time looking at video of eyeballs, and we also developed new tools to do photoreal feathers. We were using Yeti in Maya, a hair engine, and we worked with the developer to develop procedural feathers based on hair, so every feather was composed of hair curves."
Will adds, "When they decided to make the film PG-13, this shot was deleted, but we understand that it will be included on the Director's Cut DVD. In the future, we know we'll be able to use it for birds on other projects."
"Another aspect of developing Athens is that we had to deliver flyover shots of the environment for the trailer -- but we hadn't finished the shots for that part of the film," says Nicolas. "It happened that the shot they wanted for the trailer was much shorter than the one in the film, but the two weren't connected in any way -- they were only generally similar, so some of the work would be unique to the trailer.
"The largest unfinished element in the Athens shots that we were working on for the film, and that we would also need for the trailer, was the lighting -- so we developed a "day cycle" for the lighting, to precisely mimic the light from sunrise to sunset, and have it work from different angles. We were able to specifically show the light at 8AM as different from the light at 2PM, and how it would look from different directions -- shadows, reflections and so on -- to provide as many choices as possible for the composite.
Milk's gorgeous recreation of the amphitheatre and structures of the Acropolis of Athens.
"They settled on something sunset-y, which was now easy to provide. It very quickly allowed us to provide the right kinds of glows on the marble, for example, and pointed us to the fastest ways to integrate actors into the scene as well, in the same lighting. We were very happy with how it turned out."
Will adds that it extended the same kind of flexibility to the other scenes needed for the trailer, again without worrying whether specific aspects of the shot had been worked out for the finished film. "We could replace any number of buildings, from any angle, at any level of detail. No matter what the clients wanted to add, everything worked as it needed to: the lighting was ready to go, and with procedural mapping, we could render billions of polygons very quickly because of the number of them that had been pre-rendered in the original construction."
These are the kinds of things that a small company has to do in order to stay on top of a year-long project at this scale: develop technologies that can be rapidly deployed, and leverage the work of each project for ones in the future. "We were thrilled to do something of this scale in our first year," says Will, "and the second year is already shaping up to be very busy as well.
"And if Quentin Tarantino needs a gore tool for his next film, we're ready!"
In the meantime, Athens is ready for its close-up.
All images © 2014 Paramount Pictures and Metro-Goldwyn-Mayer Pictures. All Rights Reserved.