Houdini Conjures Up Tornadoes and BAMFs for X2
Rhythm & Hues and Cinesite Hollywood used Side Effects Software's Houdini to create effects in the summer blockbuster X2: X-MEN UNITED. For example, Rhythm & Hues used Houdini and Houdini Mantra to animate and render chunks of snow and tree debris flying around the X-Jet in a scene where the plane flies through the woods. In addition, Rhythm & Hues artists were able to control water sources and turbulent current effects as well as the falling shards of shattered glass. For the X-Jet, they added engine thrusts, heat distortion and dust.
In regards to Storm's weather controlling powers, Richard Hollander, Rhythm & Hues' senior visual effects supervisor, said, "The tornadoes were animated using our in-house Voodoo application and then imported into Houdini, where particles basically drove the volumetric elements. Here, Houdini became the control surface from which all of the characteristics from the way the constructions were lit to the direction they were moving could be varied infinitely before sending out for rendering. Working this way, we were actually able to design some 93 differently tweaked tornadoes for a single sequence."
Cinesite used Houdini in more than 100 shots, mainly with the opening sequence at the White House which features Nightcrawler, a mutant who teleports himself making a "BAMF" sound and leaving behind only a trail of smoke.
"For Nightcrawler, we needed an effects and rendering pipeline that we could easily control and change on the fly to produce approval and final versions for approximately 50 'BAMF' shots," said Vijoy Gaddipati, Cinesite's lead FX td. "By contrast to having the character disappear in a puff of smoke, the idea here was more sophisticated: to stream out tendrils of black and colored smoke whenever he 'BAMFs' in and out of a scene. The extensibility of Houdini, which always gives us the possibility of hooking in our in-house tools to take things a step further, was crucial to achieving the uniqueness and impact of this effect."
Cinesite devised a workflow with Houdini acting as an API interface to drive the facility's turbulence noise generator. The live-action Nightcrawler stunt work was brought as a match-framed CG model, where this rough geometry was used as a surface from which effects and emit particles were built. The process allowed fluidic smoke-like behavior to be placed on particles, which took on the characteristics of the actor's real motion and clothing before he disappeared.
In addition, Cinesite also used Houdini to create Cyclops' beam as well as shield effects used by Dr. Jean Grey which were designed as mapped, animated geometries with VEX shaders. Pyro's CG fireballs were based on Houdini particles, deforming spheres and VEX shaders, which blend with live-action pyrotechnics. Moreover, Cinesite used Houdini to light and render elements for a lake shot, creating realistic sun glints and other atmosphere effects.
Formed in 1987, Side Effects Software (www.widefx.com), a world leader in the development of 3D graphics and special effects software, is the creator of Houdini.