A Helium ship.

A Zodanga ship.

For the crowd system, they relied on Dneg's in-house Mob and wrote tools for muscles, eyes, etc. They also worked very hard to make the green skin subconsciously like human skin so you weren't thrown out of the film. "We went toward human characteristics so the muscle system was based on human muscle but stretched out," Chiang continues. "Legacy designed the creatures with Andrew and provided ZBrush models to us and when we looked at the eyes, Andrew wanted to retain the performance of the actors and went back to white human eyes so when they evoked emotion, it resembled what the actors did. Weight was important. He wanted a lot of human characteristics and that was the challenge. We had to get the lighting and skin renderers and subsurface detail right, including the bump maps, displacement and skin sliding."

The Thern Sanctuary.

Meanwhile, Cinesite completed 831 visual effects shots, which included creating and populating the majority of environments for the film. They also converted 87 minutes of the film into stereo 3-D. Cinesite's senior VFX supervisor Sue Rowe spent several months on set in the UK and Utah; she was assisted by four other Cinesite supervisors. The sequences included Zodanga, a mile-long rusty metal tanker that crawls like a myriapod across the surface of Barsoom (supervised by Jonathan Neill); the beautiful and elegant city of Helium, with a huge glass palace in the middle (supervised by Christian Irles); the Thern sanctuary, a huge underground cave that forms around the characters as self-illuminating blue branches as they walk through it (supervised by Simon Stanley-Clamp); and the huge aerial battle between Zodanga and Helium. Supervised by Ben Shepherd, each side's airships use solar wings to travel on light. Cinesite's team also provided explosions, fire, digital doubles, a CG Thark City environment and set extensions based on photogrammetry.

Zodanga.

For Zodanga (designed by VFX art director Ryan Church), there was a lot of attention devoted to shader resource files, per frame asset visibility and prman XML stats analysis.  One of the major challenges of Zodanga is that it's a city on legs, so the design of the legs, scale, materials and rigging had to match the time period of the story, while the surfaces and weathering had to make it look like they'd seen years of service on the Mars landscape. The textures, surfaces and edges were detailed to give a dirty, industrial feel using a combination of Photoshop, Mari and Mudbox in tandem with in-house shaders and lighting development. Since Zodanga is a very boxy, utilitarian-looking city, Cinesite needed to break up a lot of the straight edges to show wear and tear on the concrete. This was done by modeling and texturing using Mudbox as well as other techniques. Compositing used a template script in Nuke as a starting point for every shot. This was populated by around 60 layers to give compositing a very granular control to be able to tweak the lighting in Nuke.

Helium.