The Curious Case of Benjamin Button, the latest film starring Brad Pitt, has been nominated for 13 Oscars, including Best Visual Effects.  Next Limit is pleased to reveal that their RealFlow software was used extensively by their visual effects clients who contributed to the film.

There is an outstanding array of visual effects in the film, justifying the Oscar nomination.  A number of breakthrough effects can be seen, including a never-before-seen underwater explosion effect using RealFlow.  This sequence was one of the most challenging fluid effects in the film with a collision between a tugboat and a German submarine.  To create it, RF expert Mark Stasiuk, co-founder and CG Supervisor at Fusion CI Studios, supervised fellow RF experts at Asylum Visual Effects in Santa Monica.

“It was a major challenge,” says Mark.  “RealFlow doesn’t have an exploding gas behavior, so I built that from scratch with scripted force fields. It’s a tremendously difficult effect to make look realistic because an underwater explosion has the behavior of a violently expanding air bubble. The volume of the explosion gets very large, very quickly.  I started with a version of Fusion’s explosion sim behavior and built a new model of the forces affecting the expanding gas. I started with a fireball, but because the effect is underwater, I had to make it behave more like a bubble.  An underwater explosion front expands rapidly, then collapses back in on itself, leaving a wake of millions of tiny bubbles that get sucked back in. The experience was kind of like sculpting smoke as it moves through the air with a couple of blow-dryers in your hands!”

“Significant R&D time was required for this effect and we knew that we’d see great results with RealFlow,” adds Mark.   “The result was outstanding underwater explosion elements; violent ripples and a surface shock-wave as the tug & sub collide.”

Another significant breakthrough using RealFlow was accomplished when Mark created water ‘rivulets’ pouring off the submarine’s surface.  “Large amounts of water move quickly as smaller streams slow to a crawl.  It’s quite a detailed and sophisticated behavior that RealFlow doesn’t do out of the box.  RealFlow fluid will typically just slide off a vertical surface.  It’s complex because this is an ‘instability driven’ behavior.  I created a fluid motion in which small drops of water stick to surfaces, but the bigger the drop the greater the tendency for it to flow down. Moving drops then naturally join with other drops to form streams. Couple this behavior with custom surface tension forces that push the flow into narrow snake-like bands and you get that characteristic rivulet-style flow we are so used to seeing on car windshields in the rain. This was a real bear to accomplish, but it worked out great.”

Next Limit co-founder and CEO Victor Gonzalez congratulated Mark and the team at Asylum Visual Effects. “The results of the work done by everyone involved are outstanding.  We´re very pleased to see effects created by our RealFlow software so prominent in this blockbuster film.  Our development team worked closely with Mark and Asylum to provide and test additional features which weren´t in RealFlow at the time.  Some of these are now packaged inside our new RealFlow RenderKit product which we have recently launched, and others will come in the next version of RealFlow.  We´d like to thank Mark and Asylum Visual Effects for continually pushing the boundaries of RealFlow´s capabilities. Congratulations on achieving these spectacular effects.” 

• Official Movie Site: The Science Behind The Curious Case of Benjamin Button

About Fusion CI Studios:

Fusion CI Studios specializes exclusively in photo-real CG fluid and particle fx. Fusion CIS provides fluid fx team supervision, tool & pipeline development, fluid assets and/or rendered elements for commercial work and feature film. www.fusioncis.com

About Asylum VFX:

Asylum Visual Effects is an award-winning visual effects studio based in Santa Monica specializing in Movies, Design, Production and Commercials. www.asylumfx.com