Author Neil Gaiman’s Coraline started out as a children’s book about a bored little girl who is lured into another world which seems to offer her everything she has ever wanted. This world is inhabited by her Other Mother, who looks exactly like her real mother except she is much more patient, is a good cook and oddly enough has buttons for eyes. Coraline quickly realizes that something is not right and this perfect world is literally shattered before her eyes.

While writing Coraline, Gaiman sent a manuscript to stop-motion animator Henry Selick. He realized that if this dark tale was going to be turned into a movie, it would need to walk a fine line between the fantastical and the fearful and who better to accomplish this than the director of The Nightmare Before Christmas.

Jump forward a few years and Coraline has been released as a beautifully hand-crafted stop motion animation. Henry Selick, working with LAIKA, a Portland, Oregon animation studio, took a practical approach to this movie and built numerous sets, puppets and intricate costumes. But while Coraline sets itself apart from the recent rush of CG animated films, computers still played an important role in realizing the director’s vision.

Houdini was chosen to tackle a number of VFX shots such as the smoke for The Other Mother’s "gravy train"; the sawdust created when The Other Wybie blows his hand away; and the candy dust and chunks when Ms. Forcible blows it out of the candy dish. The Houdini team also created one of the most surreal scenes in the movie as the Other Mother’s world is reconstructed as Coraline finds herself back at the Other House after having just walked all the way around the Other World trying to escape.

For one of the most dramatic scenes in the movie, Tom Nixon and Peter Stuart of LAIKA created a disintegrating sky with lots of debris to show the Other World as it is being broken apart by the Other Mother who is angry that Coraline is beating her at a game. For the sequence where the Ghost Children warn Coraline that the Other Mother is still a threat, Eric Kuehne and his team again used Houdini to create the painterly starry sky background.

Destroying the Other World

For the Other World deconstruction scene, LAIKA made good use of Houdini’s ability to integrate many features into a single workflow. “The system I setup for the world destruction used a combination of every Houdini context except CHOPs,” says Peter Stuart, VFX Technical Director, LAIKA.

The process started with a hand-animation of a growing crack saved out as an image sequence. A static version of the crack pattern was pre-processed with Houdini’s compositing operators to make it easier to generate correctly shaped pieces. These pieces were then fit in with the crack pattern using a Trace operation. The original image sequence was also processed with a heavy blur then used to drive a particle system. The pieces of debris were copied onto the particle system. Since the entire process was procedural it was easy to reuse in several shots with different crack animations and geometry.

To create a cost effective pipeline, Digital Assets were used to package up tools created in Houdini Master that were then used to animate in Houdini Escape. For the world destruction shots, Tom Nixon took a prototype work-flow and wrapped it into a Digital Asset. The tool even included particles which were controllable in Houdini Escape using high level controls.

Eric Kuehne also used Digital Assets for the starry sky dream so that several effects artists could quickly come up to speed while maintaining consistency in the look between all the shots. There were even some artists that did not have extensive experience with Houdini who got up to speed with the starry sky work-flow in only a couple of days.

Rapid Prototyping VFX

For Coraline, CG was only used where it was most needed. With Houdini the team could quickly prototype an effect to help the VFX supervisor determine whether to do the shot with CG or to use a practical technique. If the decision was to go with CG then Houdini's procedural nature made it easy to take the prototype and refine it for the final shots. This was a time-saver which allowed for more iterations and faster turnaround.

“One of the big advantages Houdini has over other software is the render pass management system,” says Stuart. “Especially for the Other World reconstruction shots there were quite a few elements and passes that all had to be generated twice because the movie was in stereo. Houdini’s render operators made it easy to manage all of these passes.”

LAIKA chose to use Mantra to render all of the Houdini effects. Mantra provided modern features that are easy-to-use out of the box. And the unlimited Mantra tokens provided a very cost effective solution because the team could render to as many nodes as they had access to without incurring extra costs.

Amongst all the hand-crafted wonder found in Coraline, CG was a silent partner that played a very important role. Houdini got to contribute to this amazing film and provided LAIKA with a flexible VFX pipeline that could be easily applied in different ways to different shots.

About LAIKA

Fueled by the vision of its owner, Nike co-founder and Chairman Philip H. Knight, LAIKA (www.laika.com) is an animation studio specializing in feature films, commercials, music videos, broadcast graphics and short films. It is located in Portland, Oregon.

LAIKA’s initial feature film Coraline debuted on February 6, 2009. Written and directed by Henry Selick (Nightmare Before Christmas, James and the Giant Peach) – and based on the internationally best-selling novel by Neil Gaiman – Coraline is the first major stop-motion animated feature to be shot in 3D. Combined with a prolific commercial division, LAIKA/house, the company has a 30-year animation history presenting the artistry of award-winning filmmakers, designers and animators.

In addition to numerous international honors, LAIKA has won two Academy Awards, 11 Emmy Awards, 11 Clio Awards, three London International Advertising & Design Awards, five Mobius Advertising Awards and two Cannes Lion International Advertising Festival awards.