Shape Shifting in The Sorcerer's Apprentice
There's a lot more to The Sorcerer's Apprentice than electrifying vfx -- there's also a lot of shape shifting courtesy of Asylum FX's 500 noteworthy shots: Horvath (Alfred Molina) forming out of cockroaches, a parade dragon turning into a real dragon and cars morphing into other cars.
Indeed, Asylum (under the supervision of Phil Brennan) worked on most of the vfx in the first half of the film (up to the end of the Chinatown sequence) and a few later sequences such as the Car Chase and the Mirror/Bathroom scene. Asylum also created many of the CG characters in the film such as the Chrysler Eagle, Merlin's dragon ring, Sun Lok's belt dragon and the Chinatown dragon.
Nearly all of the vfx were extremely complex and involved some sort of CG. In addition, the nature of the film meant that there were a huge number of one-off effects, all completely different, and every one had to be intricately researched, designed and developed.
"The roach sequence featured hundreds of thousands of roaches scurrying to form a vertical mass, which would resolve into Horvath," Brennan explains. "The major challenge here was to reconcile the director's artistic vision [Jon Turteltaub] with the set of physical limitations, which were implied. Individual roaches needed to be clearly climbing over each other (interacting with each other) at a believable speed and yet quickly resolve into a human form. Since all bugs would potentially influence all others, this meant that a small change to the motion of a few bugs could dramatically alter the look of the simulation as a whole. So, much work went into designing a system which allowed specific changes to be made while guiding the subsequent interactions toward a desired result."
Once the roaches knew where to go, they needed to know what to become. Each roach, based upon its final position within Horvath was assigned a texture and a material. Furthermore, the surface of each bug would deform to match the surface into which it would merge. There were flesh bugs, bone bugs, cloth bugs and fur bugs. The closer the bugs crept toward their destinations, the more their textures, materials and topologies would change until they literally became parts of Horvath. This required a system by which textures and geometric information could be passed from the model of Horvath to the individual bugs based on this unique final position (and frame).