Digital Character Construction

Introduction

• 1,300 Visual Effects Shots
• Software: Commerically-Avialable & Proprietary
• 40 characters
  • Primary Characters -- Acting Parts
  • Secondary Characters -- 'crowds', 'herds' or 'flocks'.
  • Reynolds, C. W. (1987) "Flocks, Herds, and Schools: A Distributed Behavioral Model", in Computer Graphics, 21(4) (SIGGRAPH '87 Conference Proceedings) pages 25-34. <http://www.cs.toronto.edu/~dt/siggraph97-course/cwr87/>>

Character Construction

• Kinematic Skeleton
• Girard, M. and Maciejewski, AA. 1985. "Computational Modeling for Computer Generation of Legged Figures", Proc. SIGGRAPH '85, Computer Graphics, Vol. 19, No3, pp.263-270 <http://graphics.stanford.edu/courses/cs448-01-spring/papers/girard.pdf>
• Skin-Skeleton Binding
  • Enveloper - Lemurs
  • Dinosaurs - Muscle Layer
• Skin Surface Treatment ("Look")
  • Dinosaurs - Displacement Shaders
  • Lemurs - Fur System

Kinematic Skeleton Animation

• Inverse-Kinematic Animation Control
  • Girard, M. and Maciejewski, AA. 1985. "Computational Modeling for Computer Generation of Legged Figures", Proc. SIGGRAPH '85, Computer Graphics, Vol. 19, No3, pp.263-270 <http://graphics.stanford.edu/courses/cs448-01-spring/papers/girard.pdf>

NURBS Skin

• NURBS Mathematics I -- Curves
• NURBS Mathematics II -- Surfaces
• NURBS Mathematics III -- the Basis Function
• NURBS (U, V, N) Parametric Space
• NURBS Stitching
  Seam Continuity Controlled by Tangents, Control Vertices (CV's)
  • Surface Continuity Before
  • Surface Continuity After
  • User Interface

Character Rigging - Binding Skin to Skeleton

• Articulated Skeleton
• Anatomical Muscle Layer
• Secondary Animation
  • Muscle Bulge-Stretch
  • Inertia
• NURBS Skin Registered to Muscles/Skeleton

Character Finaling - Applying Animation to Characters

• Skeleton Drives Muscles/Skin -- Inertia is Adjusted
• Character-Character, Character-Set Interaction is Generated
• First-Look at Rendered Output
• (NURBS Original)

Scene Finaling: The Final Look

• Dinosaurs - Displacement Maps
  • Painted Binary Image
  • Surface-Mapped
  • Surface Displacement
    • Steve Upstill, The RenderMan Companion: A Programmer's Guide to Realistic Computer Graphics; Addison-Wesley Publishing Co.; 1990; ISBN: 0-201-50868-0. <http://cseng.aw.com/book/0,3828,0201508680,00.html>
• Lemurs - Fur
  • Disney FurTool
• Sequence 20 -- Grass-as-Fur
  • Character-Set Interaction
• Scene Assembly
  • Lighting
  • Effects
  • Compositing
  (Video -- 1) Sequence 20 grass/fur) (DVD -- 1) Sq 7-114.5 Yar/Zini, 2) Sq 19-78.1 Neera/Carnotaur)

Conclusion

The Tools and Techniques Used Were the Best we Could Find or Build Ourselves.

Artists created the visual appearance and the animation of the characters.