Proprietary Software Brings Prince of Persia and clash of the Titans to Life.

The movie Prince of Persia: The Sands of Time is based on the Ubisoft video game and is set in the mystical lands of Persia. The film follows the story of rogue Prince Dastan, played by Jake Gyllenhaal, and a mysterious princess, played by Gemma Arterton, and their race against dark forces to safeguard an ancient dagger capable of releasing the Sands of Time – a gift from the gods that can reverse time and allow its possessor to rule the world.

Cinesite (London, UK ) a film visual effects house, has completed more than 280 shots on the new Walt Disney Pictures/Jerry Bruckheimer Films movie. Michele Sciolette, head of VFX technology at Cinesite, explains that his company used proprietary software to bring about the visual effects. “It’s unique to Cinesite,” he says. “We develop most of the tools according to the needs of every production we work on, so we are constantly in development.”

Directed by Mike Newell, Cinesite’s visual effects supervisor Sue Rowe and her team of 60 artists completed a variety of challenging and creative shots on the film which ranged from digital face replacements and set extensions through to CGI weapons and matte paintings. Spending six weeks on location in Morocco enabled Rowe to pre-plan how Cinesite would work with the limitations of the shoot, which included small sets, varied skies, and limited props. She was then able to feedback to her team who could begin previsualizing the effects.

One scene which proved to be a creative challenge for Cinesite was ‘youthening’ the king, played by Ben Kingsley, by 30 years. Cinesite’s solution was to draw upon their in-house proprietary software Motion Analyser, which enables the faces of live action actors to be manipulated to allow for corrections such as removing fine lines and wrinkles, blotches, dark patches, and hairs to enhance the look of youthfulness.

Another sequence required Cinesite to create a full CG lioness. Using Autodesk Maya, the lioness was generated to reflect a creature that looked starved and malnourished. “We really wanted to present a lioness who was bordering on emaciated to emphasize her need to hunt,” said Rowe. “To achieve this look we graded the lioness to have washed-out fur and deeply emphasized the bone structure around her rib cage and hips.” As the hunt scene progresses the lioness is speared through the mouth by a CG spear, which was also created using Maya.

Cinesite also worked on the movie Clash of the Titans, which used proprietary software from Cinesite, but it was different from the software used on Prince of Persia.

One of their key sequences in Clash of the Titans was a big battle sequence involving giant scorpion-like creatures called Scorpiochs. One of the biggest challenges was generating CG dust, sand and gravel particles for the battle. Scorpiochs throwing warriors around a desert would naturally stir up dust and debris, but as they’re CG characters, very little debris was generated on the shoot. So they needed to develop a customized particle simulation solution.

They wrote a completely new fluid dynamics simulation pipeline centered on Houdini and rendered through Mantra. It was designed to create fluid dust simulations, gravel hits and terrain deformation where the scorpiochs’ feet hit the ground, and sand and light in the atmosphere. The simulation was fully self-shadowing and interactive with the scorpiochs’ geometry. Without developing this proprietary software, they wouldn’t have been able to create the amount of dust, sand, and gravel needed to make the interaction between the live action characters and the CG scorpichs look realistic.

They also developed a completely new 2D and 3D pipeline that could handle anamorphic imagery whilst working with plates that had had the lens distortion removed. Custom software was created to track the lens distortion data and apply post processes to all the CG renders to reapply the correct distortion.

For the “youthening” effect, Cinecite discarded the traditional approach of trying to soften wrinkles and other signs of ageing by using simple image filtering techniques because this tends to produce a rather artificial painterly look. Instead, they wanted to be able to reflect skin which looked young, but still had all the nice subtleties and details of ‘real’ skin.

The approach taken was based on the idea of capturing still photographs of a person of the desired age and then transferring all the details of their skin into the performance of lead actors Sir Ben Kingsley and Ronald Pickup.
The first challenge faced was to be able to animate the young skin texture to follow all the deformations and motion of the skin in the actors’ performance. This was achieved using proprietary software, Motion Warping. The software enables us to track every pixel in an image and accurately replicate its motion.

The second challenge was to blend the young skin texture while retaining all the dynamic lighting effect on the skin. They developed a collection of Detail Transfer proprietary tools that allowed extractration details from one image and seamlessly blending them in another context. All of these tools have been developed as plug-ins to their Shake compositing system. The combination of the Motion Warping and Detail Transfer tools in the hands of skilled artists made these shots possible.


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