siggraph-2009The last session I took in today was a more production focused session “Making it Move”.  Again, there were four session:

  • Geometric Fracture Modeling in “Bolt”
  • Simulating the Balloon Canopy in “Up”
  • Fight Night 4: Physics-Driven Animation and Visuals
  • B.O.B.: Breaking Ordinary Boundaries of Animation in “Monsters vs. Aliens”

Read some cliff-notes of these presentations after the break.

First up was some guys from Disney talking about their custom geometric fracturing tool they built for “Bolt”.  They were apparently unhappy with the current offerings so opted to build their own tool as a plugin for Maya.  Using randomized seed points and approximated voronoi regions, it’s capable of breaking arbitrary shapes into any number of fragments with exact alignment, like “puzzle pieces” he repeatedly said.

One interesting question came up after his talk when someone asked him what his tool offered over BlastCode.  He said he had never heard of BlastCode. Never heard of BlastCode?  Wha?

After that was a great presentation from Eric Froemling and Jon Reisch about the modeling of the balloons in Pixar’s “Up”.  This has been covered before, how they did it all with rigid body animations, but he showed alot more detail than shown previously.  Early attempts were done with procedural motion, but that created far too much motion to be realistic.  Then they tried using CFD particle simulations replacing them particles with geometry, and he demonstrated a hilarious “nuclear balloon armageddon” video.  Finally they gutted their existing ODE-based rigid body simulation tools to create an external simulation tool capable of several hundred-thousand bodies at a time, driven entirely via small python scripts.

The next talk was from Frank Vitz and Georges Torres from Electronic Arts to talk about their new boxing PS3 game “Fight Night Round 4”.  If you haven’t seen the game then I recommend it.  I hadn’t fully seen what was involved, but the game has realistic muscle flexion, face distortion, and realistic sweat and blood spray.  They discussed several of the internal mechanics of the game such as the “magnet system” to keep stray body parts (elbows, etc) getting in the way of punches.  One of the most impressive parts was the discussion of the facial deformation system, which was based on the existing verlet cloth solver.  They modfiied it to incorporate folding (return to the starting state at the end) and several dampening parameters, and found it made a great solid body deformer.

The last talk was from Dreamworks’ Terran Boylan about the process of building and animating the “Bob” character in Monsters vs Aliens.  A lot of information has come out about this since the movie’s release, and much of his information was repeats.  He did however get into great detail of the rigging of “Bob”, which actually incorporated three rigs:  An armless patch-based model, the “jellybean” model, and an isosurface model with arms.  The first two contained full UV coordinates which could then be projected onto the isosurface model, to allow for a fully texture-compliant isosurface of Bob.  One great number from Bob is that it took 94 weeks to animate and build bob, and 15,000 lines of code.  Each frame of Bob took 2.5min to process, because of the isosurface extraction.

It was a great collection of talks, but now I’m beat.  Looking forward to tomorrow!