Canadian studio Intelligent Creatures faced down some major technical challenges to create an ever-changing mask whose inkblots betray the feelings of its wearer, Watchmen’s anti-hero Rorschach.


Following numerous attempts to bring writer Alan Moore’s hugely popular comic book series Watchmen to the big screen, 300 director Zack Snyder released his much anticipated film adaption in March this year.

Created by Moore, artist Dave Gibbons and colourist John Higgins, the original 12-part comic book Watchmen tells the tale of superheroes set in an alternate reality that runs parallel to the 1980s.

Often dubbed unfilmable, the graphic novels’ storyline of a group of retired vigilantes – Ozymandias, Rorschach, The Comedian, Nite Owl, Silk Spectre, and Dr. Manhattan – was deemed too complex and lengthy to work as a movie.

Yet Snyder delivers a film that is astonishingly faithful to the book. Better yet for hardcore fans, the film pays such close attention to detail that many shots even mirror the comic book frames themselves.

Key to the movie’s success is the work of a raft of visual-effects studios responsible for delivering Snyder’s vision. One of the film’s key visual-effects challenges was the mask of Rorschach, which was accomplished by visual-effects studio Intelligent Creatures.

One of the film’s main protagonists, Rorschach, wears a cloth mask that, as part of the fabric, displays a constantly morphing inkblot (based on the designs used in Rorschach inkblot testing).

Intelligent Creatures was Interested in the project from the start, and landed the gig thanks to a speculative test sequence it created, primarily of Rorschach and the motion of the blot.

“The reaction was very positive,” says Intelligent Creatures VFX supervisor Lon Molnar, “and led eventually to us being brought onboard as the Rorschach crew.”

The project presented two exceptional challenges for the IC team. First was the replacement of the live-action actor’s head with a full CG hooded mask, positioned seamlessly between the character’s live-action scarf and fedora, which duplicated the actor’s mouth and facial movements when he spoke.

The team also had to create an animated inkblot that looked and moved like liquid within the fabric of the CG mask and formed into the various shapes to suit key moments in the film as required by the director.

“We had a massive challenge ahead of us to match-move the head of a major character in the movie for so many shots. Rorschach was going to get a lot of close-ups, so our tracking had to be able to hold up to the closest scrutiny,” says Jeff Newton, IC’s 3D supervisor.

“Blending the CG mask into the live-action plate was also very tricky,” adds Greg Astles, IC’s 2D supervisor. “In many cases, we wanted to preserve the practical stand-in mask fabric, as it was bunching up or creating folds and shadows in a way that would have been time-consuming to accomplish in CG. This meant that our textures and lighting had to be spot-on, so that we could achieve a seamless blend between CG and practical masks.”

DIY mo-cap effects


This was made more complex by the fact that there was no opportunity to carry out on-set facial mo-cap of actor Jackie Earl Haley, who plays Rorschach. Instead, the IC team had to track Haley’s in-camera performance.

The team used 2D tracking dots painted onto the physical mask the actor wore on camera, in order to gather 2D data for the deforming parts of his face, such as the muscle movements around the mouth and jaw while speaking in close-ups shots.

The movement of the actor’s head and torso were tracked and resolved as a 3D match-move along with camera movement using PFTrack, a tracking program from The Pixel Farm.

“We used PFTrack as our starting point for match-moving as we wanted to take advantage of its geometry tracking technology,” says Newton.

“There were a lot of shots where Rorschach is too far from the camera, or moving too fast, or both, to pick up the tracking markers on the practical mask, so we knew we couldn’t rely on feature tracking alone.”

The match-moves were honed in Maya, which was used for the CG mask animation and for the inkblot animation. The IC team developed their own solution to perfect the CG mask: using proprietary animation software to augment Maya, 2D data was projected through the 3D match-moved virtual camera onto the geometry of the Rorschach mask which had already been animated with 3D movement.

The result, explains Newton, was a faux- 3D facial performance of the actor. “This gave us an accurate copy of Jackie’s performance, from the point of view of the camera, but it lacked the depth information that would bring it to life when we lit the shots,” he says.

For many shots in which the actor spoke, or his mask deformed, the faux 3D facial match-move was good enough for the team to reproduce the performance.

However, keyframe animation was needed for some of the close-up shots. “Our animators did a great job of taking this data, choosing the best bits, adding to it where necessary and adding depth to it,” says Newton.

With the animation complete and signed off, the mask was brought into Side Effects Houdini for lighting and rendering. “We chose Houdini for a few reasons: we had an in-house ‘bake-off’ between various rendering solution and found the Houdini’s Mantra not only had the quality and speed we were looking for, but it was also cost-effective,” says Newton.

“We also wanted to put a subtle fuzz of fur over the mask to enhance the feel of the fabric in close-up. With Houdini we found it easy to optimize the fur – we needed only to create a few guide curves in the interface and generating the rest of the hair at the last moment in the renderer.”

The team also used Nuke to composite the shots. “We decided to break out all the lights and shadows into separate passes, and then duplicated Houdini’s layering process in Nuke, giving comp near-complete control over affecting the lighting that 3D provided for us,” says Greg Astles.

“In this way, we were able to dial back a particular shadow if it was too dark, or darken or intensify a single light if need be.”

Testing the inkblot


“Creatively, the biggest challenge from my point of view was the inkblot itself,” says Lon Molnar. “We know that Zack had some very specific shapes he wanted to hit at key moments in the story, and we also knew that he wanted to be as faithful as possible in spirit to Dave Gibbons’ artwork.

"We also had to give the inkblot a fluid, organic feel that would sell it as ‘real’ on screen, to show it to be constantly boiling and seeping through the fabric of the mask.”

The production’s art department created the 15 hero inkblot drawings that the director wanted for key shots, as well sketches that showed how the blots should look when on Rorschach’s face. To create the inkblot animation, the IC team reviewed numerous off-the-shelf 2D packages including Flash and Toon Boom.

None, however, offered the team the control or task-specific ease of use required by the animators to animate 300-plus shots in the time frame allowed.

They quickly realized that the solution was to develop its own proprietary 2D animation software to use alongside Maya.

The inkblot animation software was written to mimic the 2D animation process, explains Astles. As traditional animators using pen and paper, IC’s animators were able to use a stylus and tablet to draw the outline of inkblots.

This meant that the animator could draw the keyframe shapes for each blot without needing to push and pull each component control vertex at each keyframe.

While different mathematical formula, such as de Boor’s algorithm, were considered for the animation, the team finalized on trimming the inkblot shapes using closed NURBS curves.

The in-house software gave the ability to change the amount of control vertexes in a curve at any time in the animation process.

Once the inkblot animation was complete, the planar surfaces, which were created to line up with the UV space of the mask geometry, could be rendered from an orthographic camera to create a hard-edged blot animation texture.

Intelligent Creature submitted the test sequence for the mask in late 2007 and finished work on the film nearly a year later.

The good news for the studio – aside from getting to work on what is set to be one of the key films of 2009 – was that its work on the film mushroomed from an original commission for 235 shots, to 326 shots that included city extensions, matte paintings, wire and rig removal and CG elements including rain and blood.






The no-mo-cap mask

According to Lon Molnar, visual effects supervisor at Intelligent Creatures, the Watchmen project posed considerable creative and technical challenges for the team.

The main problem in developing Rorschach’s mask lay with having to produce the same effects that would have been conventionally developed through the use of multiple cameras or motion-capture equipment on set.

As neither were available to the Intelligent Creatures team, Molnar had to develop a technique that effectively produced a faux-3D performance.



The man in the mask

To achieve the look of the inkblot bleeding through of the cloth of the mask, the Intelligent Creatures team had to recreate the mask’s cloth. Starting with a scan of the actual fabric created by the art department, and some work in Photoshop, the team were able to break it down into its component parts.

The screen-printed top layer was extracted for a displacement map, but the other maps – colour, displacement and spec – were recreated procedurally in Houdini, basing it on the Photoshop work. “That way we knew we could go as close to the mask as was necessary,” explains Jeff Newton, Intelligent Creatures’ 3D supervisor.

Credits

Project: Watchmen
VFX studio: Intelligent Creatures, intelligentcreatures.com
Software: Adobe Photoshop, Autodesk Maya, Side Effects Houdini, The Pixel Farm PFTrack, The Foundry Nuke