• movement within scene, movement of camera over time
• much work!
• interactive vs non-interactive 
• flight simulation, games 
• film and video 
• scientific and industrial simulations 
• tools for the artist
• character animation
• humans vs animals and robots
• subjective realism
• facial animation

Double Buffering

Keyframing

• from traditional animation
• cubic splines 
• parameters vs time






• curved path through space 
• arc-length reparameterization, velocity curves









• direct specification of keyframes
• flexible but time consuming

Inverse Kinematics

• articulated figures
• animator controls `end effectors'
• IK adjusts intermediate joint angles as necessary

Motion Capture

• capture movement of real actors
• playback on CG character using IK
• technology: set of 6 DOF sensors
• problem: editing the motion after recording

Dynamics 

• simulation
• laws of physics: F = ma
• solve for a, update position, display, repeat
• particle systems, bouncing balls
• swinging chains and ropes, falling objects
• control problem for humans and animals