Course Review
Computer Animation and Visualisation
Taku Komura
Topics● Color mapping● Keyframe animation, Inverse Kinematics● Motion Capture● Motion Blending● Facial capture and transfer● Physically-based character animation
– Forward dynamics
– Inverse dynamics
● Crowd animation– Flocking
– Continuum crowds
– RVO
●
Topics (2)
● Fluid Simulation– SPH
● Volume rendering ● Contouring ● Flow visualisation
– Glyphs, streamline, streakline
● 3D Mesh processing● Shape comparison, retrieval● Information Visualisation
Topics● Color mapping● Keyframe animation, Inverse Kinematics● Motion Capture● Motion Blending● Facial capture and transfer● Physically-based character animation
– Forward dynamics
– Inverse dynamics
● Crowd animation– Flocking
– Continuum crowds
– RVO
.....
●
Character Animation
● Motion Capture●
Pseudo-inverse method
Iteratively updating the generalized coordinates so that the position constraints are satisfied
e: end effector position
g: target location
while ( Δe is too far from g) {
compute the Jacobian matrix J
compute the pseudoinverse of the Jacobian matrix J
compute change in joint DOFs: Δq=J Δe
apply the change to DOFs, move a small step of q=q+ Δq
}
Δe =JΔq
+
+
http://thewanderingtech.50webs.com/Flash/IK%20Comparison%20Application/IKCompare.html
Physically-based animation
• Using Newton's laws of dynamics to simulate various phenomena
– Drop objects in the scene, and let them collide and see what happens
– Blowing hair by a dryer
– Add force to the bodies and torque to the joints and simulate the movements of human figures
Forward / Inverse Dynamics
• Forward dynamics: Adding force and simulate what happens
Then, update the velocity and position by the computed acceleration
INPUTOUTPUT
Forward / Inverse Dynamics
• Inverse dynamics: Given a motion, calculate the force / torque
INPUT
OUTPUT
Forward Dynamics for Human Animation
– Passive motions
• Falling down (No force or torque, rag-doll)• pushed and stepping back
– Voluntary motions → Walking, Running
Flow Visualisation
● Glyphs, streamlines, streaklines
Processing 3D Surface Data
● 1) Capture the data (by stereo vision, range scanner)● 2) Registration (if the data was captured by multiple
attempts)● 3) Adding the topology : converting to mesh data● 4) Smoothing● 5) Decimation● 6) Remeshing
Metaballs (implicit surface)
Mesh Shape Editing
● Laplacian mesh editing● As rigid as possible shape interpolation● Barycentric coordinates
Shape Matching and Retrieval
● Local Features– Curvature
● Global Features– Reeb graphs, medial axis
● Both – Heat Kernel Signature
–
Information Visualisation
● Parallel coordinates – multivariate data● Graph visualisation● Literature visualisation
Thank you !!
● Good luck