Computer Animation Lectures 2 - after Spring Break

Last modified: 14:18 Apr 12, 1999

I divided the lectures page in half to make it easier to read. The first 14 lectures are described here.

Lecture 15: Constrained Dynamics

Here we move on to better methods for handling interactions between objects in simulations

Required Readings:	Witkin & Baraff Physics Notes 3 (Constrained Dynamics) Interactive Dyanamics Chapter 3 of my Thesis
In-Class Viewing:	Early CMU interactive dynamics videos.
Optional Readings:	We won't talk much about collision detection and response. If you're interested in learning about it, the best place to start is Baraff's on-line course notes. There is a large and rich literature on how to handle the simulation of rigid bodies and hierarchies. For articulated figures, there has been lots of work on how to evaluate the equations of motion very efficiently.

Lecture 16: Implementing and Generalizing Constraints

The methods we described extend to simulating/controlling a wider array of things. In this lecture, we'll try to make that leap. We'll also take more of an optimization-based view of manipulating and controlling things.

The main body of this lecture will be methods for actually building simulation and optimization-like things. This include methods for computing the constraint functions and their derivatives, as well as how to make the computations go fast.

Required Readings:	Chapters 3, 4 and 5 of my thesis. Inverse Kinematics Positioning Using ... (you've already read this paper, but we'll revisit it now)
In-Class Viewing:
Optional Readings:	Other of my papers, or other parts of my thesis, for ideas on other things to control by constraints. Surles' work on interactive constraint-based manipulation of proteins.

Lecture 17: Spacetime Constraints and Control of Physical Simulations

Spacetime Constraints are an easy idea that are hard in practice. I find them a fascinating idea (in fact, they are what got me started in doing animation in the first place).

I will also cover the Witkin Welch physics paper since it has lots of interesting ideas on how to use physics in animation, other than the obvious "make a world and watch it go" movies (like Baraff does).

Required Readings:	Fast Animation and Control of Nonrigid Structures Spacetime Constraints
In-Class Viewing:
Optional Readings: Control of Physical Simulations	Issacs and Cohen There were several "inverse dynamics" papers in graphics journals in the late 80s. I am not sure which ones to recommend. The work of Al Barr's group at Caltech was very interesting in building physical simulations and inverse dynamics to make things self-assemble. In particular, Ronen Barzell's '88 siggraph paper or book would have been good readings, but too hard to distribute to require.
Optional Readings: Spactime Constraints	Michael Cohen. Interactive Spacetime Control for Animation. Proceedings SIGGRAPH '92. Liu, Cohen and Gortler. Hierarchical Spacetime Control. Proceedings SIGGRAPH '94. Some of the motion-editing with Spacetime papers (me, Popovic, ...) that we'll get to later in the course

Lecture 18: Basics of Motion Editing

In this talk, we'll begin to look at the problem of motion editing.

We'll focus on signal processing methods. The lecture will include a brief introduction to basic signal processing, and a discussion of why the methods are appropriate for motion editing tasks.

Required Readings:	Motion Warping by Popovic and Witkin Motion Signal Processing by Bruderlin and Williams
In-Class Viewing:
Optional Readings:	Any signal processing text Fourier Principles for Animation by Unuma, et al

Lecture 19: Motion Editing with Spacetime Constraints

Required Readings:	Motion Editing with Spacetime Constraints. Retargetting Motion to New Characters
In-Class Viewing:	Spacetime Swing and other motion editing examples
Optional Readings:	Physically-Based Motion Transformations Efficient generation of transitions using Spacetime Constraints

Lecture 20: Randomized Motion Generation

In class presentation by Ryan Fruit.

Required Readings:	Real-Time Responsive Animation with Personality
In-Class Viewing:	Danse Interactif On-line demos
Optional Readings:	Improv Flocks, Heards, and Schools: A distributed Behavioral Model. Artificial Fishes: Physics, Locomotion, Perception, Behavior

Lecture 21: Human Simulation

In class presentation by Suanhsi Yong and Keith Thoresz.

Required Readings:	Animating Human Athletics
In-Class Viewing:	Atlanta in Motion Alien Occurance
Optional Readings:	Adapting Simulated Behaviors For New Characters Goal-Directed, Dynamic Animation of Human Walking Real time virtual humans Strength Guided Motion Interactive Behaviors for Bipedal Articulated Figures

Lecture 22: Genetic Algorithms and Controller Search

In class presentation by Samuel Williams and Soumya Ray

Required Readings:	Spacetime Constraints Revisited
In-Class Viewing:	Tom Ngo's videos
Optional Readings:	Towards Practical Automated Motion Synthesis Evolving Virtual Creatures Genetic Programming for Articulated Figure Motion Genetic Programming Evolution of Controllers for 3-D Character Animation

Lecture 23: Facial Animation

In class presentation by Paul Salmon and Wilson Chang

Required Readings:	Synthesizing Realistic Facial Images from Photographs
In-Class Viewing:
Optional Readings:	Video Re-Write A Muscle Model for Animating Three-Dimensional Facial Expressions Computer Generated Animation of Faces Making Faces Computer Facial Animation DECFACE

Lecture 24: Subdivision Surfaces

In class presentation by Jeff Ballard and Nicholas Rasmussen

Required Readings:	Subdivision Surfaces for Character Animation
In-Class Viewing:	Geri's Game
Optional Readings:	Exact Evaluation of Catmull-Clark Subdivision Surfaces Non-Uniform Recursive Subdivision Surfaces Interactive Multi-Resolution Mesh Editing Efficient, Fair, Interpolation using Catmull-Clark Surfaces

Lecture 25: 3D User Interfaces

In class presentation by Yu Gu and Igor Ivanisevic

Required Readings:	Randy Pausch's NSF proposal Sketch: An Interface for Sketching 3D Scenes
In-Class Viewing:	Sketch video Some of my videos
Optional Readings:	Grasping Reality Through Illusion Snap-Dragging in 3 Dimensions Facile 3D Manipulation Three Dimenstional Widgets

Randy Pausch is a professor at CMU. His Alice project is an interesting testbed for 3D User Interface research. His NSF proposal is an interesting thing to read because it provides a good introduction not only to a variety of the methods he's worked on, but also, a nice sales pitch for his philosophy.

Lecture 26: Non-Photorealistic Rendering

In class presentation by Michael Wade and Daniel Wierstra

Required Readings:	Processing Images and Video for an Impressionist Effect
In-Class Viewing:
Optional Readings:	Paint by Numbers Real-Time, Non-Photorealistic Rendering Painterly Rendering for Animation Computer Generated Pen-and-Ink Illustration Rendering Parametric Surfaces in Pen-and-Ink

Lecture 27: Image Warping and Morphing

In class presentation by Arpan Biswas and Scott McElroy

Required Readings:	Recent Advances in Image Morphing
In-Class Viewing:	Morph Examples
Optional Readings:	Feature-Based Image Metamorphisis Animating Images with Drawings Image Metamorphisis with Scattered Feature Constraints Feature-Based Volume Metamorphisis