Looks like a simple rig in Maya to compliment the game nicely, and they use morph shapes for the facial emotes which seems a natural fit given the squashiness of the character.

A few weeks back, details of the facial animation rig and other workflow info had been posted on the Japanese XSI website and I was planning to extract information via the google tranlation and observation alone, but someone beat me to it, (and managed to do a much better job than I would ever have). Head on over to Chris Evans’ (Tech-Art Lead at Crytek) blog for full translations of the following sections:

• MGS4 Facial Animation
• MGS4 Character Pipeline
• MGS4 Cluster Constraint Setup

Regarding the  facial setup, it looks very reminiscent of the same method I saw presented at ADAPT 2007 by Aaron Holly of Disney. This involved a similar setup of a bone rig driven by a mesh giving the two following important advantages.

1. It was highly flexible and able to be moved between multiple similar faces as the animation is stored on a nurbs mesh that drives the bones rather than the bones directly, therefore allowing for varying bone positions.
2. If using a pose-based facial animation solution such as FaceFX, the bones travel along the curve of a nurbs surface rather than a simple linear translation, therefore better mimicking the movement of skin across the skull.

This is certainly something I’d be keen to try in the near future given that it now appears to have successfully been put through a full videogame production.

Pixar: How Pixar Animation Studios Brings Characters To Life

Andy Schmidt – Animator on Ratatouille

This was an incredibly valuable lesson in the workflow for polishing an animated feature, which has some lessons we can directly employ for our own peer-review processes. The initially self-deprecating yet entertaining Andy Schmidt took us through the challenges of creating the characters for Ratatouille, (namely, how to turn vermin into an appealing character) before moving on to Pixar’s general approach to taking a scene through various levels of polish.

The biggest element of the talk that struck me was the difference between an animated film and videogame cutscene schedule – two supposedly similar projects in concept, with the key being when voice-over is recorded. Below is a comparison between Pixar and what is my experience of the norm for large-scale videogame project storytelling, taking a direct comparison with only the elements shared across mediums.

Pixar Animated Features – Videogame Cutscenes

Story Story
Script Lighting (Often unchanged from the level’s default)
Voice-Acting Storyboard
Storyboard Animatic
Pre-viz (Character placement, Cameras) Script
Animation Blocking Voice-Acting (Temporary in-house VO)
Animation Polishing Animation Blocking
Add Simulations (Skin, Cloth, Hair etc.) Voice-Acting
Add VFX Animation Polishing
Lighting Add VFX

Additionally, the four VO and Animation segments in the videogame timeline often contain a loop as the VO is reworked due to the script often being in flux – this unnatural workflow is every bit a by-product of not locking down the script early in the project, which is something our industry really needs to take strive towards.

Notes on Pixar character development:

• Each character was given a signature movement style to differentiate themselves from one another, this is something that would be great to explore with a game containing only a few diverse characters, as game animation is often diluted to facilitate sharing among multiple characters.
• Much research was undertaken on both rats and the cooking world, with the team joining a local cooking course and live rats brought in to the studio and hooked up to a web-cam. This unfortunately offered nothing more than lots of footage of sleeping rats, so old favourite the BBC Motion Library proved invaluable for rat movement.
• Among the many character-development sketches on show were what Andy called “Mechanical Sketches”, where the artist would envision how the skeleton rig might be placed inside the characters – something that is clearly considered at every stage of the process.
• Extremely finished paintings were created over the top of in-progress models to provide early lighting/material tests.
• Pose character sheets were devised to illustrate various correct-vs-incorrect methods for animating the characters – essentially style sheets setting a brand bible for each character.
• A decision made late in the character-development process to begin the movie with the rat characters walking on all fours necessitated a complete rebuilding of the character rig to allow optimum animation for both biped and quadruped motion.

Notes on Pixar rig development:

• As soon as the first rigs are created, vast amounts of animation tests are performed to try and break them when pushing characters to extremes. Similarly, facial rigs are run through calisthenics animations to push the expressions as far as they can go. At this stage, many character-defining walkcycles are also prototyped. Of interest, the walkcycles were completely symmetrical, pointing towards Pixar having a tool or method to quickly facilitate this.
• The animators work closely with the riggers and modeling department during the creation process. At the self-declared risk of sounding arrogant, Andy described the animators at Pixar as being the “vehicle” for telling the story, so modelers etc. bend over backwards to support them.
• One example of communicating change requests to modelers involved notes drawn over screenshots to illustrate the exact changes and improvements required.
• Animation tests would be created to test the reach of each character, therefore defining how some scenes might play out. The example shown highlighted a rather large chef’s inability to move in close to the kitchen-top, therefore necessitating additional collision deformation on his body.
• Similar tests are performed to find how far cloth and other dynamic elements of a character’s person could be pushed. It was interesting to note that by this stage the models were already fully complete in design.

Notes on Pixar animation style:

• Squash & Stretch is an integral part of their animation style.
• Many Pixar animators come from a 2D only background, including the speaker, as animation is seen as interchangeable between mediums. In my own experience, hiring good animators without any 3D experience has always proved fruitful, undermining perceived difficulties within own industry of hiring animators that have experience in Maya over Max and vice versa.
• Andy strongly recommended Ed Hooks book, “Acting for Animators”. Attendeding one of his lectures I also found it to be quite insightful, basing much of his observation on a character’s centre of mass defining his movements, as well as useful ideas concerning what goes on outside of a scene you are animating determining what plays out inside it.
• Andy went back to basics and displayed some inspiring examples of bouncing balls he’d found on the web. Noting that John Travlota begins every new character by creating a unique walk for him, Andy moved on to various walkcycles of his own creation, moving from realistic to highly stylized to illustrate how to promote caricature.
• Next, he showed a selection of admittedly rough though long character tests created to explore how characters might hold kitchen objects based on video research. These long tests would later prove useable for background characters in the final movie.
• Facial tests were also performed by matching frame-for-frame against movie clips of actors used as inspiration for the creation of the Pixar characters.
• Finally, “Lineups”, where all the major characters were lined up side by side performing actions in a brief scene, were created to explore consistency.

Notes on Pixar review process:

• Shots are divided out among animators almost like a casting process depending upon their particular strengths, such as humour, timing, caricature etc.
• Peer review is paramount, where showing in-progress shots for advice from the rest of the team is consistent in “Dailies” meetings, though it was not clear if this was mandatory. This is something essential to maintain, (and increase), quality among any group of animators, though a weekly assembly should suffice.
• The Director, in this case Brad Bird, uses a laser-pointer to highlight areas for work on the projector screen, though a video showed him to be incredibly animated when illustrating his comments – despite appearing to micro-manage the acting.
• A lot of, (but not all), Pixar animators shoot their own animation reference – this is sometimes sped up to fit better with the cartoony style.
• Their test renders for review, just like the Halon ones, were done with black bars at the top and bottom containing information such as the filename, version number, date, frame numbers, camera info and state, eg. blocking, polishing etc.
• In summary, it appeared the motto was to rework, rework and rework again to achieve the levels of quality Pixar is known for.

Finally, while most videogames unfortunately still rely on text and exposition, Andy finished his talk with an educational section stating that “Theatrics” should be used to tell a story without the viewer noticing, breaking this into the following insights.

• “You can say a lot with key-posing”: Mentioning storytelling poses, Andy informed us that you can really nail a scene in one pose. This is best illustrated in paintings, but he also showed some extreme poses from sports press that really showed more motion than many animated sequences. He advised to “sneak extreme poses” into animations to really sell a movement, using a scene from The Jungle Book as an example where Mowgli’s head is literally buried in his ass when climbing a tree. I myself have noticed rig-destroying examples like this being used to great effect in the Dead or Alive series of games to really accentuate attack motions.
• “Playing an action until something happens”: A simple observation to never have characters idle without at least something appearing to be going on in their heads – something not easily avoidable in videogames unfortunately.
• “What’s happening vs what’s really happening”: Basically, what is the scene really about? This idea centres around layered character motivation affording a vehicle for more interesting dynamic between characters where secret motivations allow acting on two levels – that of what the other characters know and of what the audience knows.
• “What does your character want? What do they do to get it?”: Another motivational observation, though this time a more general rule about character actions defined by their needs and what they do to achieve them.
• “What happens to your character isn’t as important as what you feel about it”: Essentially a separation of the events playing out around your character and how they choose to react, allowing the story to focus more on the characters themselves rather than what events take place for a deeper more human storytelling experience.

Looking at the image below, they at least animate using Lightwave, though how much of their pipeline relies on it is unknown. Perhaps the Japanese industry is different as a whole, as in the West we mostly use either Maya or 3D Studio Max. Lightwave is more favoured among high-end artists for it’s renderer, not its animation system.

The rig below includes the wireframe mesh of the shadow-casting model, but otherwise displays fairly standard IK/FK limbs, with an aim constraint to animate the head, (presumably also able to be turned off). This aim-target is of interest if it is actually exported with the animation and used in the real-time target system as is the case in HalfLife 2′s “Source” engine.

I like the cute 3D hands on the floor that presumably denote all the finger controls, but still prefer to have those controls seperate in a Channel Box (Maya) or Modifier Panel (Max). Note the boneless cloth garment, showing that they have a seperate system for that element rather than being bone-driven.

What really intrigues me though are the long bones at the extremities – possibly something to do with their real-time IK system, but more probably with the standout feature – the deforming collision of the Colossi themselves, whereby they calculate the player’s position on the collision as a single spherical point making it easier to react to the deforming mesh, (below).

The aforementioned real-time IK system appears to support a fairly standard 2-bone setup (affecting just the last two in the horse’s leg), save that it not only affects the limbs but also raises and angles the whole character in one solution. In past games I’ve encountered these as two seperate systems, with the latter affected by a check on the ground normal rather than an average of the various IK limbs. See below for a comparison – first without, then with the root being affected.

Finally, the most impressive (and hopefully soon to be widely adopted) element of the entire movement system centres around what they call their “motion-addition” system – essentially the combining of procedural and animator-created motion to give true fluidity without the sloppiness of purely-procedural movement, or rigidity of keyframes alone.

A physical simulation drives animation of the bones, causing the character to rotate around his single handhold, and presumably to arc the body and delay the limbs based on that motion as seen in the image below. This was not only used to afford the flailing motion of the player character while the Colossus violently attempts to shake him off, but also for the natural movement of the horse.

This combination of procedural calculation that drives motion tweaked by an animator, (or even better, purely procedural systems that are simply fed data in the form of exported animations) is the next step in more natural-feeling motion in our in-game characters.

“Movement becomes wooden if purely controlled by a program, but also a pre-made animation won’t fit in right. It is the combination which makes it work. When I saw this working in real time, I was more than a little impressed! I think it has become a truly wonderful system to combine the animator and programmer.” - Fumito Ueda, Director

For the original article in its entirety (including images), go here, with an English translation here.