Hellboy II was the largest character animation project ever undertaken by Double Negative, and the real challenge was gathering all the different pieces of a creature pipeline developed on other movies. All images © Universal.

Dozens of new creatures, hundreds of character animation shots, some of the weirdest characters ever put on screen... Hellboy II: The Golden Army (opening today from Universal) definitely plays in a much higher league than 2004's Hellboy. The sequel has Hellboy (Ron Perlman) and his team of misfits confronting a horde of mythical creatures who rebel against humanity.

The movie was the largest character animation project ever undertaken by lead vfx vendor Double Negative. The facility had just delivered Grawp for Harry Potter & the Order of the Phoenix, as well as the saber toothed tiger and the terror birds for 10,000 BC, so lessons learnt from these prior projects were incorporated into the nascent creature pipeline.

"The real challenge here was to gather all the different pieces of a creature pipeline developed on other shows," says co-CG Supervisor Andrew Chapman. "We had to form a complete character pipeline that would handle the vast array of different creatures we were animating, as well as a very high volume of creatures within a single scene, up to about 5,000 Tooth Fairies in some shots."

Double Negative's pipeline was modeled in Maya, ZBrush and XSI; rigging and lighting were done in Maya; effects work were done in both Maya and Houdini; rendering was done in RenderMan through a proprietary Maya-RenderMan tool called Rex; and compositing was done in Shake.

Animators used Maya as the primary animation software. NaturalMotion endorphin was used a little in the Golden Army sequences. "We developed some new tools to help with shots involving large numbers of characters, working on the principle of caching," explains Animation Supervisor Eamonn Butler. "The animator would select a rigged character and cache it out to geometry. It could be switched back to an animatable rig at any point, allowing the animators to have a large number of characters in the shot at any one time without suffering too much slowdown. This was particularly useful for the Tooth Fairies sequences."

The process of animating the Elemental was centered on the primary animation principles of line of action, silhouette and negative space. 

Splitting Up the Workload
The modeling and rigging teams started work as soon as the project was awarded in February 2007. "By starting immediately, we were able to keep the crew smaller and more manageable, so more focused and highly skilled in their crafts," Senior Visual Effects Producer Steve Garrard notes. "Due to the long length of the shoot, it was agreed to turnover certain sequences whilst the film was still shooting principle photography. Although feedback wasn't as instantaneous as it would become in post, this was key as we ended up providing CG animation for over 500 shots.