During animation reviews, director Genndy Tartakovsky would draw over animation frames to push them into even more extreme positions, resulting in a film that reflects his signature, caricatured animation style. Here he draws over frames on his tablet.

When Genndy Tartakovsky infused his monster mash, Hotel Transylvania, with a Tex Avery-style hand-drawn aesthetic, it required an overhaul at Sony Pictures Animation (SPA).

"Starting it and not having any idea what it was going to be as the story was still being rewritten was really hard and makes you nervous," Tartakovsky concedes about his first feature. "Then you know what the tone is and it becomes easier."

Tartakovsky admits he was kind of like his Drac in search of control. "Every week was a new challenge whether it was technical or creative. I couldn't control the pieces as much as I'm use to." 

In fact, the technical demands nearly upended SPA, especially after its recent strides with photo-realism. They worked on the fly for a year keeping up with Tartakovsky: creating new pipeline, breaking rigs and coming up with various deforming tweaks to get the right squash-and-stretch in CG. They emphasized lattice, clusters, sculpt deforms, wrinkle free and blend shapes. They also came up with a visual language that was strong on silhouettes and drop off detail in the distance (trees look like inkblots).

During one sequence in Humanville, for instance, Drac sees that one of the zombie's heads has fallen off and he zips through the crowd very quickly and becomes snake-like.

And similar to Glen Keane on Disney's Tangled, Tartakovsky drew over the footage to illustrate the extreme poses that he desired. The animators were then on their own to figure out how to translate it. "What scared us initially is that we had a lot of assets but they were built for a different picture, from a different director's point of view," explains Dan Kramer, the VFX supervisor. "The characters were the same, the castle was the same but we had to roll with it. We had to figure out how to get there. And we never wanted to compromise the story or Genndy's vision. And so we had to make those decisions very quickly and decisively. Luckily, we had a director who knew what he wanted."

Movie frame with Genndy’s drawover in white. All images courtesy of Sony Pictures Animation. Copyright: © 2012 Sony Pictures Animation, Inc.

Final movie stills incorporating Genndy’s input.

But in the past they've hesitated to let a character get off model. You're going to change features where it doesn't feel like the same character anymore. "Genndy wanted to dispel the notion that we were breaking the character or taking it off model," Kramer adds. "What was important to him was that he got the pose he wanted. He was OK if a character looked different because it was a momentary action. Sometimes it was all about taking a character from one place to another; other times it was more in your face. Genndy wasn't afraid to stretch characters. He doesn't have much experience with CG animation. You might be stretching polygons in such ways that the textures get really soft or look stretchy. Or you might be twisting the polys in a way that it creates a discontinuity in how the model shades. I just had to let it go. To Genndy, it was a matter of hitting the emotion he wanted. When he did draw overs, it was freeing for the animators. And it's changed my viewpoint in being a little looser."

Tartakovsky really upped the imaginations of the artists by pushing the CG ideas into more of a 2D world. "Certainly, we thought of it more as a 2D movie in our approach," concedes character animator Bill Haller. "Of course, there were always the technical challenges we'd have to overcome with rigs and stuff and we thought of it more in poses and breakdowns even trying to simulate smears.

Movie frame with Genndy’s drawover in white.

Final movie stills incorporating Genndy’s input.

"On almost every shot, 20% of the effort went into tweaking the rig to more of a hand-drawn pose. We have proprietary tools to alter the rigs in Maya if we need to. And there are tools out there that we haven't used that much. One was the Silhouette tool, where you can draw a wire over your character and strengthen the geometry through the wire to get a better silhouette. Genndy likes to compose his silhouettes. And he wanted a lot of silhouettes and wanted to suppress detail outside the line action, and wanted to blur things out in the background.