Datasheet
2 Chapter 1: Character Skeletons
Character Pipeline
e details of a character pipeline vary based on the character and change from company
to company, and artist to artist, but for the most part, the overall process doesn’t change.
In this book, the pipeline is as follows:
PHOTO REAL PIPELINE
1. Establish the geometry.
2. Build a skeleton with basic functionality.
3. Add traditional skin weighting.
4. Create the facial anatomy.
5. Set up skin simulation.
6. Add facial hair using Fur.
7. Create and style hair.
8. Dress the character.
9. Implement secondary character eects.
10. Capturing a performance.
11. Add lighting and rendering.
Traditional skin weighting or binding only goes so far. e character in this book is
fully clothed; therefore, his body doesn’t need intense skin deformations. But the charac-
ter needs to act. He needs to be able to speak and be convincingly expressive. To achieve
this level of realism, it’s crucial to match the real world as much as possible. Driving the
character’s face is an anatomically correct muscle system. e muscles squash and stretch
and push and pull on the skin like real muscles.
Replicating human anatomy is half the battle. e muscles may move perfectly by
themselves, but it’s a dierent story when you need all of them to work together to form a
smile or a frown. In comes performance capture. e term was coined by James Cameron
while working on Avatar. Performance capture is the recording of every movement made
by an actor. Well, maybe not every movement, but enough motion to identify speech,
expressions, and of course full-body activities.
Skin Evaluation
Prior to adding joints, you should always evaluate your character’s geometry or skin. It
should have proper edge ow and enough faces for detailed deformations. Computer
speed is constantly on the rise. anks to more RAM and accelerated GPUs, soware
has been able to increase production complexity. In the past, numerous techniques were
used to push as much of the character’s geometry as possible o until render time. is is
still practiced today; but you can add more geometry to the character’s actual bind. e
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