Shang-Chi: Wenwu's Rise to Power
Karen Moltenbrey
November 4, 2021

Shang-Chi: Wenwu's Rise to Power

Shang-Chi and the Legend of the Ten Rings opens with a flashback on father Wenwu’s rise to power, with a montage of battle scenes against various armies from different locations throughout history while using the power of the rings. 
The scene opens on Wenwu mounted on horseback with his band of followers laying siege to a Seljuk-style castle as the warrior single-handedly overcomes the defending army, with the battle culminating in a rotating single shot of him wreaking havoc with the legendary Ten Rings of Power before smashing down the castle’s defenses with a blast of ring power. The sequence then follows Wenwu’s progress through frozen forests where, during another battle, he captures a treasure cart, laying the foundation for his fortune.

The 112 VFX shots by Method Studios in Melbourne in this segment of the film involved face replacements, crafting digital horses (with a rider dismounting into battle), the brother-sister face-off at the gambling club, and set extensions. But, its main work entailed creating the look for the rings seen throughout the film, including four main sequences spanning the opening shots to the end battle.

The base ring asset was modeled by hand in Autodesk’s Maya, while Adobe’s Substance Painter was used extensively for texturing, along with Chaos’ V-Ray for shader work and rendering. The rings had rig controls to discreetly tweak their shape and scale to fit onto Wenwu’s arm, which was also re-created in CGI during a number of shots, allowing the artists to tune the amount of deformation and contact between the rings and the skin.

The ring powers were much more challenging to generate than the base ring asset, however. “We tried to use elemental forces as much as possible as a basis for the various ring effects, to make it feel natural even though it was fantastical,” says Christopher Townsend, production visual effects supervisor. “There’s also a lot of logic and a sense of grounding to them.”

Method was involved early on with look-dev for the ring effects — which, says Townsend, was a very long, ongoing process, as the group dialed up and down their strength and subsequent elemental effect. Eventually each ring had a different effect depending on which ring power was in use at the time. According to Joshua Simmonds, VFX supervisor at Method Melbourne, the first hero shot of the rings leaving Wenwu’s arms in close-up was staged to display their otherworldly beauty and power as energy forms between the rings, suggesting a powering up. “They need to dangle around the character, and then when they’re activated, they rise up the forearm to become equidistant along the forearm,” he explains.

The ring shield effect — which Wenwu creates to defend against the raining arrows during the castle attack — was much more challenging, Simmonds adds. This was due to the speed at which the conqueror is moving on horseback, combined with the extreme whip-like motion of the rings, resulting in a lack of visual clarity in the simulations based on the individual rings. The solution, he says, was found by combining world-space simulations with local space, which were then motion-compensated to connect it all back again. Effects and lighting contributed many render passes to the compositors for fine detail control of color and intensity.

In all, 30 effects elements, both physical-based and emissive, were used by compositors to achieve the final effect, which also included collisions from airborne arrows.

Method’s sequences further required a digital version of Wenwu, which was based on detailed scans and texture references. Many of the shots involved CG forearms and hands for the ring integration. The arms had a full muscle and skeletal system, while the artists used SpeedTree (from Interactive Data Visualization, recently acquired by Unity) to grow the veins down to the capillary level for use with subdermal glow effects.

The animators also generated crowds by feeding a large volume of in-house motion capture into Method’s custom (SideFX) Houdini Crowd system to form the basis of the crowd shots. The crowd data was then passed from Houdini to Maya via a lightweight USD wrapper, which in turn rendered a custom procedural in V-Ray leveraging the Houdini Engine. In addition, Method’s custom Maya Vignettes system enabled the auto-simulation of clothing and hair for crowd shots that required specific placement of action by animators.

“Our crowd system made use of Houdini’s robust dynamics to simulate physical reactions to impacts, which could in turn be promoted to Maya animation rigs for further performance refinements, including higher-quality cloth and hair simulation,” explains Simmonds.

As for Wenwu’s battle costume, it had complex, multi-layered clothing underneath armor, presenting challenges with tailoring in Marvelous Designer’s software as well as with cloth simulation. His long hair also required the placement of hundreds of guide hairs, which were in turn groomed with multiple tools to match the on-set hair. This CG hair was further used to augment the plate when Wenwu didn’t have bluescreen coverage.