Helper Joints: Advanced Deformations on RunTime Characters
Game Developers Conference 2005 Session
Helper Joints: Advanced Deformations
on RunTime Characters
Speaker: Jason Parks (Technical Artist, Sony Computer Entertainment America)
Time/Date: 12:00-1:00 Firday, March 11th, 2005
Track: Visual Arts
Format: 60-minute Lecture
Experience Level: Advanced - Requires experience and familiarity with subject.
Description: Everybody knows how to make characters look, deform, and move
well for rendered cinematic sequences. Things start to get challenging when
you are limited to the tools you have available to you at run-time. Luckily
there is a way to get all those great deformation tweaks and rigs to work
in your game and not just on the screen in your powerful 3D package on your
desktop.
There is one simple way to create advanced deformations like muscle bulging, skin-sliding, and general deformation fixes at run-time: extra joints or "helper joints". Because all run-time engines already support joints, it is a relatively small step to optimize your game engine to accommodate the use of a couple or even hundreds of extra helper joints.
This course will review some of the ways to use procedurally-driven extra helper joints to get the deformations you'd really like to see in your game.
Idea Takeaway: The technical
artist learns:
* Why an artist would need more joints in their skeleton? Especially those
that are not even an approximation to real-life anatomy.
* Where the major problem-areas are in character deformation.
* How an artist should make these extra joints transform.
* What systems an artist can use to drive these extra joints.
* What tools an artist can create to automate the creation of these joints.
Intended Audience and Prerequisites: This course will be most valuable to technical artists who have spent a lot of time painting weights on characters and pulling their hair out trying to find that perfect combination of weights to fix that last vert which just will not behave properly, or anybody who has spent a lot of time making custom blendshapes/morphtargets to fix major binding problems.
[Download
Presentation]
This is the presentation only from the GDC website. It contains
still images but does NOT contain the 270+ MBs of movies, sorry.
Research
["Anatomy
of Movement” by Blandine C. Germain ]
Anatomy of Movement presents a dynamic, integrated approach to
the study of the physical structures of the musculoskeletal system and their
functional relationship to the movements of the human body.
[PAN
Arts by Warwick Mellow ]
Character setup techniques, with isolated deformations.
["Building
Efficient, Accurate Character Skins from Examples" by Mohr/Gleicher]]
Siggraph 2003 paper on auto-computing number and weighting of
Helper Joints.
Playblasts
[SmoothBind]
Standard Smooth Bind of LeftShoulder.
External
Links
Muscle Systems:
[cgMuscle]
Open source muscle plug-in for maya, poly/NURB muscle model in
beta, no deformer yet, works great!
[CG|Toolkit: MuscleTK]
Muscle plug-in for Maya with skin simulation, launches November
1rst
[Comet
Muscle System]
Muscle plig-in for Maya, hasn't been updated in a while, no beta,
looks very promising
[cgCharacter
ACT]
Muscle plug-in for 3DS Max, early beta for Maya with no deformer
Pose Deformer Systems:
[Body
Blend Reference]
bodyBlend.mel script which automates corrective blendShape creation
and animation process.
Products
[Custom
Character Tookit]
Maya Techniques™ | Customer Character Toolkit allows you
to explore the methodologies and techniques involved with building a character
pipeline.
Updated: 3/16/05
Email: Jason Parks