Framestore Creates VFX for Iron Man 3
To make sure this was achieved, the whole anatomy of the characters was modelled – from skeletons and muscles right down to blood vessels and capillaries, which resulted in some super heavy rigs (combated by setting up a pipeline that meant each element could be dealt with separately). It was also a big task to deform that amount of geometry and Framestore developed its own deformer to make sure everything would fit inside the skin.
“After rigging and modelling we moved onto tracking, which was a big challenge as there was body and facial tracking in every shot,” explains Alexis. “We started with camera track, body track and facial deformation, using 3D equalizer. The trackers did amazing work in a very short space of time. The team was quite small yet they tracked over a hundred shots!”
From there the FX team began controlling the movement of Extremis by flowing particles along the veins and arteries. “This was very choreographed and art directed, so it wasn’t easy! We needed to have full control on particle speed, flow and direction. That was a set-up done in Houdini by Selcuk Ergen (Lead FX TD) and his team. By the end of the show it was just pressing buttons – it was very successful.”
The flow of Extremis is so hot it emits steam, something created by the Maya team, led by Horacio Mendoza, using a fluid simulation. “The challenge was the deadline,” says Alexis. “It was maximum two days per shot for the steam, so we had to have a very strong set up in order to do fast simulation.”
Lighting obviously played a huge part in revealing the depth Marvel was after. Point clouds were used to drive lighting internally beneath the skin, which was refractive, so the deeper beneath the skin the light was, the blurrier it was.
One of the main challenges Framestore had to face was to be able to reproduce the Extremis effect on four different characters and seven different sequences. The full capacity of the Framestore pipeline was used to create a small factory so that, just by just pressing a few buttons, FX TDs and Lighters were able to update their shots if the model, track or even the look was changed. Framestore used its propriety solver, Flush, to create the long simulation for the fire, which needed to interact with a character walking through it. “In that shot the person is practically full CG, except for the clothes, hair, teeth and lips, we rendered everything, so it’s a full body-track,” says Alexis.
In less than two weeks Framestore completed a digital double takeover for one of the main villains, replacing their entire body in CG from the moment they’re shot to the moment they hit the ground. The scene also required some further regeneration work and a few finishing touches to make sure they looked evil enough to deserve being shot!