SCA 05: Eurographics/SIGGRAPH Symposium on Computer Animation

Permanent URI for this collection


Imitation as a First Step to Social Learning in Synthetic Characters: A Graph-based Approach

Buchsbaum, D.
Blumberg, B.

Autonomous Pedestrians

Shao, Wei
Terzopoulos, Demetri

Motion Modeling for On-Line Locomotion Synthesis

Kwon, Taesoo
Shiny, Sung Yong

Capture and Synthesis of Insect Motion

Gibson, D. P.
Oziem, D. J.
Dalton, C. J.
Campbell, N. W.

Video-Based Character Animation

Starck, J.
Miller, G.
Hilton, A.

Modeling and Animating Gases with Simulation Features

Schpok, Joshua
Dwyer, William
Ebert, David S.

Simulation of Smoke based on Vortex Filament Primitives

Angelidis, Alexis
Neyret, Fabrice

Pushing People Around

Arikan, Okan
Forsyth, David A.
O Brien, James F.

An Efficient Search Algorithm for Motion Data Using Weighted PCA

Forbes, K.
Fiume, E.

Particle-Based Simulation of Granular Materials

Bell, Nathan
Yu, Yizhou
Mucha, Peter J.

An Art-Directed Wrinkle System for CG Character Clothing

Cutler, Lawrence D.
Gershbein, Reid
Wang, Xiaohuan Corina
Curtis, Cassidy
Maigret, Erwan
Prasso, Luca

Morphable model of quadrupeds skeletons for animating 3D animals

Reveret, Lionel
Favreau, Laurent
Depraz, Christine
Cani, Marie-Paule

Directable Animation of Elastic Objects

Kondo, Ryo
Kanai, Takashi
Anjyo, Ken-ichi

Spatial Keyframing for Performance-driven Animation

Igarashi, T.
Moscovich, T.
Hughes, J. F.

Analyzing the Physical Correctness of Interpolated Human Motion

Safonova, Alla
Hodgins, Jessica K.

Transferable Videorealistic Speech Animation

Chang, Yao-Jen
Ezzat, Tony

Simulating Complex Hair with Robust Collision Handling

Choe, Byoungwon
Choi, Min Gyu
Ko, Hyeong-Seok

AER: Aesthetic Exploration and Refinement for Expressive Character Animation

Neff, Michael
Fiume, Eugene

Progressive Multiresolution Meshes for Deforming Surfaces

Kircher, Scott
Garland, Michael

Robust Quasistatic Finite Elements and Flesh Simulation

Teran, Joseph
Sifakis, Eftychios
Irving, Geoffrey
Fedkiw, Ronald

Particle-based Viscoelastic Fluid Simulation

Clavet, Simon
Beaudoin, Philippe
Poulin, Pierre

Simple and efficient compression of animation sequences

Sattler, Mirko
Sarlette, Ralf
Klein, Reinhard

Animosaics

Smithy, Kaleigh
Liuz, Yunjun
Klein, Allison

Particle-Based Fluid-Fluid Interaction

Müller, Matthias
Solenthaler, Barbara
Keiser, Richard
Gross, Markus

Adapted Unstructured LBM for Flow Simulation on Curved Surfaces

Fan, Z.
Zhao, Y.
Kaufman, A.
He, Y.

Taming Liquids for Rapidly Changing Targets

Shi, Lin
Yu, Yizhou

Fast and accurate goal-directed motion synthesis for crowds

Sung, Mankyu
Kovar, Lucas
Gleicher, Michael

Behavior Planning for Character Animation

Lau, Manfred
Kuffner, James J.

Vortex Fluid for Gaseous Phenomena

Park, Sang Il
Kim, Myoung Jun

Group Motion Graphs

Lai, Yu-Chi
Chenney, Stephen
Fan, Shao Hua

XFluids in Deforming Meshes

Feldman, Bryan E.
O Brien, James F.
Klingner, Bryan M.
Goktekin, Tolga G.

Helping Hand: An Anatomically Accurate Inverse Dynamics Solution For Unconstrained Hand Motion

Tsang, Winnie
Singh, Karan
Fiume, Eugene

Outside-In Anatomy Based Character Rigging

Pratscher, Michael
Coleman, Patrick
Laszlo, Joe
Singh, Karan

Physically Based Rigging for Deformable Characters

Capell, Steve
Burkhart, Matthew
Curless, Brian
Duchamp, Tom
Popovic, Zoran

Physically Based Grasping Control from Example

Pollard, Nancy S.
Zordan, Victor B.


BibTeX (SCA 05: Eurographics/SIGGRAPH Symposium on Computer Animation)
@inproceedings{
10.2312:SCA/SCA05/009-018,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Imitation as a First Step to Social Learning in Synthetic Characters: A Graph-based Approach}},
author = {
Buchsbaum, D.
 and
Blumberg, B.
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/009-018}
}
@inproceedings{
10.2312:SCA/SCA05/019-028,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Autonomous Pedestrians}},
author = {
Shao, Wei
 and
Terzopoulos, Demetri
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/019-028}
}
@inproceedings{
10.2312:SCA/SCA05/029-038,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Motion Modeling for On-Line Locomotion Synthesis}},
author = {
Kwon, Taesoo
 and
Shiny, Sung Yong
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/029-038}
}
@inproceedings{
10.2312:SCA/SCA05/039-048,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Capture and Synthesis of Insect Motion}},
author = {
Gibson, D. P.
 and
Oziem, D. J.
 and
Dalton, C. J.
 and
Campbell, N. W.
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/039-048}
}
@inproceedings{
10.2312:SCA/SCA05/049-058,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Video-Based Character Animation}},
author = {
Starck, J.
 and
Miller, G.
 and
Hilton, A.
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/049-058}
}
@inproceedings{
10.2312:SCA/SCA05/097-106,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Modeling and Animating Gases with Simulation Features}},
author = {
Schpok, Joshua
 and
Dwyer, William
 and
Ebert, David S.
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/097-106}
}
@inproceedings{
10.2312:SCA/SCA05/087-096,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Simulation of Smoke based on Vortex Filament Primitives}},
author = {
Angelidis, Alexis
 and
Neyret, Fabrice
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/087-096}
}
@inproceedings{
10.2312:SCA/SCA05/059-066,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Pushing People Around}},
author = {
Arikan, Okan
 and
Forsyth, David A.
 and
O Brien, James F.
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/059-066}
}
@inproceedings{
10.2312:SCA/SCA05/067-076,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
An Efficient Search Algorithm for Motion Data Using Weighted PCA}},
author = {
Forbes, K.
 and
Fiume, E.
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/067-076}
}
@inproceedings{
10.2312:SCA/SCA05/077-086,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Particle-Based Simulation of Granular Materials}},
author = {
Bell, Nathan
 and
Yu, Yizhou
 and
Mucha, Peter J.
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/077-086}
}
@inproceedings{
10.2312:SCA/SCA05/117-126,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
An Art-Directed Wrinkle System for CG Character Clothing}},
author = {
Cutler, Lawrence D.
 and
Gershbein, Reid
 and
Wang, Xiaohuan Corina
 and
Curtis, Cassidy
 and
Maigret, Erwan
 and
Prasso, Luca
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/117-126}
}
@inproceedings{
10.2312:SCA/SCA05/135-142,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Morphable model of quadrupeds skeletons for animating 3D animals}},
author = {
Reveret, Lionel
 and
Favreau, Laurent
 and
Depraz, Christine
 and
Cani, Marie-Paule
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/135-142}
}
@inproceedings{
10.2312:SCA/SCA05/127-134,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Directable Animation of Elastic Objects}},
author = {
Kondo, Ryo
 and
Kanai, Takashi
 and
Anjyo, Ken-ichi
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/127-134}
}
@inproceedings{
10.2312:SCA/SCA05/107-116,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Spatial Keyframing for Performance-driven Animation}},
author = {
Igarashi, T.
 and
Moscovich, T.
 and
Hughes, J. F.
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/107-116}
}
@inproceedings{
10.2312:SCA/SCA05/171-180,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Analyzing the Physical Correctness of Interpolated Human Motion}},
author = {
Safonova, Alla
 and
Hodgins, Jessica K.
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/171-180}
}
@inproceedings{
10.2312:SCA/SCA05/143-152,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Transferable Videorealistic Speech Animation}},
author = {
Chang, Yao-Jen
 and
Ezzat, Tony
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/143-152}
}
@inproceedings{
10.2312:SCA/SCA05/153-160,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Simulating Complex Hair with Robust Collision Handling}},
author = {
Choe, Byoungwon
 and
Choi, Min Gyu
 and
Ko, Hyeong-Seok
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/153-160}
}
@inproceedings{
10.2312:SCA/SCA05/161-170,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
AER: Aesthetic Exploration and Refinement for Expressive Character Animation}},
author = {
Neff, Michael
 and
Fiume, Eugene
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/161-170}
}
@inproceedings{
10.2312:SCA/SCA05/191-200,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Progressive Multiresolution Meshes for Deforming Surfaces}},
author = {
Kircher, Scott
 and
Garland, Michael
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/191-200}
}
@inproceedings{
10.2312:SCA/SCA05/181-190,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Robust Quasistatic Finite Elements and Flesh Simulation}},
author = {
Teran, Joseph
 and
Sifakis, Eftychios
 and
Irving, Geoffrey
 and
Fedkiw, Ronald
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/181-190}
}
@inproceedings{
10.2312:SCA/SCA05/219-228,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Particle-based Viscoelastic Fluid Simulation}},
author = {
Clavet, Simon
 and
Beaudoin, Philippe
 and
Poulin, Pierre
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/219-228}
}
@inproceedings{
10.2312:SCA/SCA05/209-218,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Simple and efficient compression of animation sequences}},
author = {
Sattler, Mirko
 and
Sarlette, Ralf
 and
Klein, Reinhard
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/209-218}
}
@inproceedings{
10.2312:SCA/SCA05/201-208,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Animosaics}},
author = {
Smithy, Kaleigh
 and
Liuz, Yunjun
 and
Klein, Allison
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/201-208}
}
@inproceedings{
10.2312:SCA/SCA05/237-244,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Particle-Based Fluid-Fluid Interaction}},
author = {
Müller, Matthias
 and
Solenthaler, Barbara
 and
Keiser, Richard
 and
Gross, Markus
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/237-244}
}
@inproceedings{
10.2312:SCA/SCA05/245-254,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Adapted Unstructured LBM for Flow Simulation on Curved Surfaces}},
author = {
Fan, Z.
 and
Zhao, Y.
 and
Kaufman, A.
 and
He, Y.
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/245-254}
}
@inproceedings{
10.2312:SCA/SCA05/229-236,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Taming Liquids for Rapidly Changing Targets}},
author = {
Shi, Lin
 and
Yu, Yizhou
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/229-236}
}
@inproceedings{
10.2312:SCA/SCA05/291-300,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Fast and accurate goal-directed motion synthesis for crowds}},
author = {
Sung, Mankyu
 and
Kovar, Lucas
 and
Gleicher, Michael
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/291-300}
}
@inproceedings{
10.2312:SCA/SCA05/271-280,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Behavior Planning for Character Animation}},
author = {
Lau, Manfred
 and
Kuffner, James J.
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/271-280}
}
@inproceedings{
10.2312:SCA/SCA05/261-270,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Vortex Fluid for Gaseous Phenomena}},
author = {
Park, Sang Il
 and
Kim, Myoung Jun
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/261-270}
}
@inproceedings{
10.2312:SCA/SCA05/281-290,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Group Motion Graphs}},
author = {
Lai, Yu-Chi
 and
Chenney, Stephen
 and
Fan, Shao Hua
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/281-290}
}
@inproceedings{
10.2312:SCA/SCA05/255-260,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
XFluids in Deforming Meshes}},
author = {
Feldman, Bryan E.
 and
O Brien, James F.
 and
Klingner, Bryan M.
 and
Goktekin, Tolga G.
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/255-260}
}
@inproceedings{
10.2312:SCA/SCA05/319-328,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Helping Hand: An Anatomically Accurate Inverse Dynamics Solution For Unconstrained Hand Motion}},
author = {
Tsang, Winnie
 and
Singh, Karan
 and
Fiume, Eugene
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/319-328}
}
@inproceedings{
10.2312:SCA/SCA05/329-338,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Outside-In Anatomy Based Character Rigging}},
author = {
Pratscher, Michael
 and
Coleman, Patrick
 and
Laszlo, Joe
 and
Singh, Karan
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/329-338}
}
@inproceedings{
10.2312:SCA/SCA05/301-310,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Physically Based Rigging for Deformable Characters}},
author = {
Capell, Steve
 and
Burkhart, Matthew
 and
Curless, Brian
 and
Duchamp, Tom
 and
Popovic, Zoran
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/301-310}
}
@inproceedings{
10.2312:SCA/SCA05/311-318,
booktitle = {
Symposium on Computer Animation},
editor = {
D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
}, title = {{
Physically Based Grasping Control from Example}},
author = {
Pollard, Nancy S.
 and
Zordan, Victor B.
}, year = {
2005},
publisher = {
The Eurographics Association},
ISSN = {1727-5288},
ISBN = {1-59593-198-8},
DOI = {
10.2312/SCA/SCA05/311-318}
}

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Recent Submissions

Now showing 1 - 35 of 35
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    Imitation as a First Step to Social Learning in Synthetic Characters: A Graph-based Approach
    (The Eurographics Association, 2005) Buchsbaum, D.; Blumberg, B.; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    The processes and representations used to generate the behavior of expressive virtual characters are a valuable and largely untapped resource for helping those characters make sense of the world around them. In this paper, we present Max T. Mouse, an anthropomorphic animated mouse character who uses his own motor and behavior representations to interpret the behaviors he sees his friend Morris Mouse performing. Specifically, by using his own motor and action systems as models for the behavioral capabilities of others (a process known as Simulation Theory in the cognitive literature), Max can begin to identify simple goals and motivations for Morris s behavior, an important step towards developing socially intelligent animated characters. Additionally, Max uses a novel motion graph-based movement recognition process in order to accurately parse and imitate Morris s movements and behaviors in real-time and without prior examples, even when provided with limited synthetic visual input. Key contributions of this paper include demonstrating that using the same mechanisms for movement and behavior perception and production allows for an elegant conservation of representation, and that the innate structure of motion graphs can be used to facilitate both movement parsing and movement recognition.
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    Autonomous Pedestrians
    (The Eurographics Association, 2005) Shao, Wei; Terzopoulos, Demetri; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    We address the difficult open problem of emulating the rich complexity of real pedestrians in urban environments. Our artificial life approach integrates motor, perceptual, behavioral, and cognitive components within a model of pedestrians as individuals. Our comprehensive model features innovations in these components, as well as in their combination, yielding results of unprecedented fidelity and complexity for fully autonomous multi-human simulation in a large urban environment. We represent the environment using hierarchical data structures, which efficiently support the perceptual queries of the autonomous pedestrians that drive their behavioral responses and sustain their ability to plan their actions on local and global scales.
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    Motion Modeling for On-Line Locomotion Synthesis
    (The Eurographics Association, 2005) Kwon, Taesoo; Shiny, Sung Yong; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    In this paper, we propose an example-based approach to on-line locomotion synthesis. Our approach consists of two parts: motion analysis and motion synthesis. In the motion analysis part, an unlabeled motion sequence is first decomposed into motion segments, exploiting the behavior of the COM (center of mass) trajectory of the performer. Those motion segments are subsequently classified into groups of motion segments such that the same group of motion segments share an identical footstep pattern. Finally, we construct a hierarchical motion transition graph by representing these groups and their connectivity to other groups as nodes and edges, respectively. The coarse level of this graph models locomotive motions and their transitions, and the fine level mainly captures the cyclic nature of locomotive motions. In the motion synthesis part, given a stream of motion specifications in an on-line manner, the motion transition graph is traversed while blending the motion segments to synthesize a motion at a node, one by one, guided by the motion specifications. Our main contributions are the motion labeling scheme and a new motion model, embodied by the hierarchical motion transition graph, which together enable not only artifact-free motion blending but also seamless motion transition.
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    Capture and Synthesis of Insect Motion
    (The Eurographics Association, 2005) Gibson, D. P.; Oziem, D. J.; Dalton, C. J.; Campbell, N. W.; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    We present an integrated system that enables the capture and synthesis of 3D motions of small scale dynamic creatures, typically insects and arachnids, in order to drive computer generated models. The system consists of a number of stages, initially, the acquisition of a multi-view calibration scene and synchronised video footage of a subject performing some action is carried out. A user guided labelling process, that can be semi-automated using tracking techniques and a 3D point generating algorithm, then enables a full metric calibration and captures the motions of specific points on the subject. The 3D motions extracted, which often come from a limited number of frames of the original footage, are then extended to generate potentially infinitely long, characteristic motion sequences for multiple similar subjects. Finally a novel path following algorithm is used to find optimal path along with coherent motion for synthetic subjects. The result is a system that, from a potentially small number of original multi-view frames, can generate a whole swarm of novel synthetic subjects all moving in a coherent and natural manner. The proposed system has two major advantages over existing systems, 1) that traditional motion capture techniques cannot in general be used for very small subjects and 2) minimal expense and user input is required to generate, complex, high quality, CG animation.
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    Video-Based Character Animation
    (The Eurographics Association, 2005) Starck, J.; Miller, G.; Hilton, A.; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    In this paper we introduce a video-based representation for free viewpoint visualization and motion control of 3D character models created from multiple view video sequences of real people. Previous approaches to videobased rendering provide no control of scene dynamics to manipulate, retarget, and create new 3D content from captured scenes. Here we contribute a new approach, combining image based reconstruction and video-based animation to allow controlled animation of people from captured multiple view video sequences. We represent a character as a motion graph of free viewpoint video motions for animation control. We introduce the use of geometry videos to represent reconstructed scenes of people for free viewpoint video rendering. We describe a novel spherical matching algorithm to derive global surface to surface correspondence in spherical geometry images for motion blending and the construction of seamless transitions between motion sequences. Finally, we demonstrate interactive video-based character animation with real-time rendering and free viewpoint visualization. This approach synthesizes highly realistic character animations with dynamic surface shape and appearance captured from multiple view video of people.
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    Modeling and Animating Gases with Simulation Features
    (The Eurographics Association, 2005) Schpok, Joshua; Dwyer, William; Ebert, David S.; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    In modeling natural phenomena, artists often compromise the benefits of direct control for the visual realism of physics-based simulation. For gases, Eulerian simulations traditionally provide realistic results, but a poor representation for artistically shaping the media. In our system, users work with a more intuitive set of continuously extracted features whose manipulation feeds back into the original simulation. This novel approach overcomes common control issues by providing modeling tools to manipulate high-level behavior in Eulerian simulations. We employ techniques in feature extraction, real-time gas simulation, and volume rendering to build an interactive system to sculpt three-dimensional flows.
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    Simulation of Smoke based on Vortex Filament Primitives
    (The Eurographics Association, 2005) Angelidis, Alexis; Neyret, Fabrice; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    We describe a method that permits the high performance simulation of fluid phenomena such as smoke, with highlevel control for the artist. Our key primitives are vortex filament and vortex ring: vorticity defines a flow as well as velocity does, and for numerous interesting flows such as smoke or explosions this information is very compact and tightly linked to the visual features of the fluid. We treat these vortices as 1D Lagrangian primitives (i.e. connected particles), which permit unbounded fluids and very accurate positioning of the features. The simulation of passive density particles for rendering is totally independent of the fluid animation itself. Thus, the animation can be efficiently simulated, edited and even stored, while the fluid resolution used for rendering can be arbitrarily high. We aim at plausible fluids rather than physical accuracy. For efficiency and stability, we introduce a new formalization of the Biot-Savart law and a modified Biot-Savart kernel. Our model also introduces a hierarchical filament structure for animation LOD, turbulent noise, and an original scheme for density particles.
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    Pushing People Around
    (The Eurographics Association, 2005) Arikan, Okan; Forsyth, David A.; O Brien, James F.; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    We present an algorithm for animating characters being pushed by an external source such as a user or a game environment. We start with a collection of motions of a real person responding to being pushed. When a character is pushed, we synthesize new motions by picking a motion from the recorded collection and modifying it so that the character responds to the push from the desired direction and location on its body. Determining the deformation parameters that realistically modify a recorded response motion is difficult. Choosing the response motion that will look best when modified is also non-trivial, especially in real-time. To estimate the envelope of deformation parameters that yield visually plausible modifications of a given motion, and to find the best motion to modify, we introduce an oracle. The oracle is trained using a set of synthesized response motions that are identified by a user as good and bad. Once trained, the oracle can, in real-time, estimate the visual quality of all motions in the collection and required deformation parameters to serve a desired push. Our method performs better than a baseline algorithm of picking the closest response motion in configuration space, because our method can find visually plausible transitions that do not necessarily correspond to similar motions in terms of configuration. Our method can also start with a limited set of recorded motions and modify them so that they can be used to serve different pushes on the upper body.
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    An Efficient Search Algorithm for Motion Data Using Weighted PCA
    (The Eurographics Association, 2005) Forbes, K.; Fiume, E.; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    Good motion data is costly to create. Such an expense often makes the reuse of motion data through transformation and retargetting a more attractive option than creating new motion from scratch. Reuse requires the ability to search automatically and efficiently a growing corpus of motion data, which remains a difficult open problem. We present a method for quickly searching long, unsegmented motion clips for subregions that most closely match a short query clip. Our search algorithm is based on a weighted PCA-based pose representation that allows for flexible and efficient pose-to-pose distance calculations. We present our pose representation and the details of the search algorithm. We evaluate the performance of a prototype search application using both synthetic and captured motion data. Using these results, we propose ways to improve the application s performance. The results inform a discussion of the algorithm s good scalability characteristics.
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    Particle-Based Simulation of Granular Materials
    (The Eurographics Association, 2005) Bell, Nathan; Yu, Yizhou; Mucha, Peter J.; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    Granular materials, such as sand and grains, are ubiquitous. Simulating the 3D dynamic motion of such materials represents a challenging problem in graphics because of their unique physical properties. In this paper we present a simple and effective method for granular material simulation. By incorporating techniques from physical models, our approach describes granular phenomena more faithfully than previous methods. Granular material is represented by a large collection of non-spherical particles which may be in persistent contact. The particles represent discrete elements of the simulated material. One major advantage of using discrete elements is that the topology of particle interaction can evolve freely. As a result, highly dynamic phenomena, such as splashing and avalanches, can be conveniently generated by this meshless approach without sacrificing physical accuracy. We generalize this discrete model to rigid bodies by distributing particles over their surfaces. In this way, two-way coupling between granular materials and rigid bodies is achieved.
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    An Art-Directed Wrinkle System for CG Character Clothing
    (The Eurographics Association, 2005) Cutler, Lawrence D.; Gershbein, Reid; Wang, Xiaohuan Corina; Curtis, Cassidy; Maigret, Erwan; Prasso, Luca; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    We present a kinematic system for creating art-directed wrinkles on costumes for CG characters. This system employs a curve-based method for creating wrinkles on reference poses, which are incorporated into a weighted matching algorithm that generates wrinkle deformations on an animated character. The wrinkle creation tool is intuitive to use and accommodates art direction. The user can easily transfer wrinkle patterns to different characters, costumes, and body types. The algorithm for evaluating wrinkles measures the local stress of a surface and creates weights that are used to interpolate between the reference wrinkle patterns during movement. This algorithm is robust and efficient, and fits well into a large-scale feature-film production environment.
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    Morphable model of quadrupeds skeletons for animating 3D animals
    (The Eurographics Association, 2005) Reveret, Lionel; Favreau, Laurent; Depraz, Christine; Cani, Marie-Paule; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    Skeletons are at the core of 3D character animation. The goal of this work is to design a morphable model of 3D skeleton for four footed animals, controlled by a few intuitive parameters. This model enables the automatic generation of an animation skeleton, ready for character rigging, from a few simple measurements performed on the mesh of the quadruped to animate. Quadruped animals - usually mammals - share similar anatomical structures, but only a skilled animator can easily translate them into a simple skeleton convenient for animation. Our approach for constructing the morphable model thus builds on the statistical learning of reference skeletons designed by an expert animator. This raises the problems of coping with data that includes both translations and rotations, and of avoiding the accumulation of errors due to its hierarchical structure. Our solution relies on a quaternion representation for rotations and the use of a global frame for expressing the skeleton data. We then explore the dimensionality of the space of quadruped skeletons, which yields the extraction of three intuitive parameters for the morphable model, easily measurable on any 3D mesh of a quadruped. We evaluate our method by comparing the predicted skeletons with user-defined ones on one animal example that was not included into the learning database. We finally demonstrate the usability of the morphable skeleton model for animation.
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    Directable Animation of Elastic Objects
    (The Eurographics Association, 2005) Kondo, Ryo; Kanai, Takashi; Anjyo, Ken-ichi; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    There is a crucial demand in the computer animation industry to make animations that blend animator-specified expressive motion with physics-based realism. We propose a novel framework to create directable animation of elastically deformable objects. The directable animation is created with animator-specified keyframes and the motion trajectory of the deformable object, while maintaining a plausible realism. Our framework mainly consists of two complementary approaches. The first is a method to control the time-varying geometry of an elastic object, using a loose key-framing technique. In our keyframing, we introduce an FEM-based elastic deformation algorithm that allows us to rearrange the elastic object motion, guided by the shape or pose specified at each keyframe. The second is a motion compensation technique, which allows us to rearrange the physical behavior of elastically deformable objects under a user-specified trajectory. The animation examples demonstrate that our framework provides plausibly realistic deformation animations with greater controllability and usability than existing approaches.
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    Spatial Keyframing for Performance-driven Animation
    (The Eurographics Association, 2005) Igarashi, T.; Moscovich, T.; Hughes, J. F.; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    This paper introduces spatial keyframing, a technique for performance-driven character animation. In traditional temporal keyframing, key poses are defined at specific points in time: i.e., we define a map from a set of key times to the configuration space of the character and then extend this map to the entire timeline by interpolation. By contrast, in spatial keyframing key poses are defined at specific key positions in a 3D space where the character lives; the mapping from the 3D space to the configuration space is again defined by interpolation. The user controls a character by adjusting the position of a control cursor in the 3D space; the pose of the character is given as a blend of nearby key poses. The user thus can make expressive motion in real time and the resulting motion can be recorded and interpreted as an animation sequence. Although similar ideas are present in previous systems, our system is unique in that the designer can quickly design a new set of keyframes from scratch, and make an animation without motion capture data or special input devices. Our technique is especially useful for imaginary characters other than human figures because we do not rely on motion-capture data. We also introduce several applications of the basic idea and give examples showing the expressiveness of the approach.
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    Analyzing the Physical Correctness of Interpolated Human Motion
    (The Eurographics Association, 2005) Safonova, Alla; Hodgins, Jessica K.; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    Two human motions can be linearly interpolated to produce a new motion, giving the animator control over the length of a jump, the speed of walking, or the height of a kick. Over the past ten years, this simple technique has been shown to produce surprisingly natural looking results. In this paper, we analyze the motions produced by this technique for physical correctness and suggest small modifications to the standard interpolation technique that in some circumstances will produce significantly more natural looking motion.
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    Transferable Videorealistic Speech Animation
    (The Eurographics Association, 2005) Chang, Yao-Jen; Ezzat, Tony; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    Image-based videorealistic speech animation achieves significant visual realism at the cost of the collection of a large 5- to 10-minute video corpus from the specific person to be animated. This requirement hinders its use in broad applications, since a large video corpus for a specific person under a controlled recording setup may not be easily obtained. In this paper, we propose a model transfer and adaptation algorithm which allows for a novel person to be animated using only a small video corpus. The algorithm starts with a multidimensional morphable model (MMM) previously trained from a different speaker with a large corpus, and transfers it to the novel speaker with a much smaller corpus. The algorithm consists of 1) a novel matching-by-synthesis algorithm which semi-automatically selects new MMM prototype images from the new video corpus and 2) a novel gradient descent linear regression algorithm which adapts the MMM phoneme models to the data in the novel video corpus. Encouraging experimental results are presented in which a morphable model trained from a performer with a 10- minute corpus is transferred to a novel person using a 15-second movie clip of him as the adaptation video corpus.
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    Simulating Complex Hair with Robust Collision Handling
    (The Eurographics Association, 2005) Choe, Byoungwon; Choi, Min Gyu; Ko, Hyeong-Seok; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    We present a new framework for simulating dynamic movements of complex hairstyles. The proposed framework, which treats hair as a collection of wisps, includes new approaches to simulating dynamic wisp movements and handling wisp-body collisions and wisp-wisp interactions. For the simulation of wisps, we introduce a new hair dynamics model, a hybrid of the rigid multi-body serial chain and mass-spring models, to formulate the simulation system using an implicit integration method. Consequently, the simulator can impose collision/contact constraints systematically, allowing it to handle wisp-body collisions efficiently without the need for backtracking or subtimestepping. In addition, the simulator handles wisp-wisp collisions based on impulses while taking into account viscous damping and cohesive forces. Experimental results show that the proposed technique can stably simulate hair with intricate geometries while robustly handling wisp-body collisions and wisp-wisp interactions.
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    AER: Aesthetic Exploration and Refinement for Expressive Character Animation
    (The Eurographics Association, 2005) Neff, Michael; Fiume, Eugene; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    Our progress in the problem of making animated characters move expressively has been slow, and it persists in being among the most challenging in computer graphics. Simply attending to the low-level motion control problem, particularly for physically based models, is very difficult. Providing an animator with the tools to imbue character motion with broad expressive qualities is even more ambitious, but it is clear it is a goal to which we must aspire. Part of the problem is simply finding the right language in which to express qualities of motion. Another important issue is that expressive animation often involves many disparate parts of the body, which thwarts bottom-up controller synthesis. We demonstrate progress in this direction through the specification of directed, expressive animation over a limited range of standing movements. A key contribution is that through the use of high-level concepts such as character sketches, actions and properties, which impose different modalities of character behaviour, we are able to create many different animated interpretations of the same script. These tools support both rapid exploration of the aesthetic space and detailed refinement. Basic character actions and properties are distilled from an extensive search in the performing arts literature. We demonstrate how all highlevel constructions for expressive animation can be given a precise semantics that translate into a low-level motion specification that is then simulated either physically or kinematically. Our language and system can act as a bridge across artistic and technical communities to resolve ambiguities regarding the language of motion.We demonstrate our results through an implementation and various examples.
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    Progressive Multiresolution Meshes for Deforming Surfaces
    (The Eurographics Association, 2005) Kircher, Scott; Garland, Michael; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    Time-varying surfaces are ubiquitous in movies, games, and scientific applications. For reasons of efficiency and simplicity of formulation, these surfaces are often generated and represented as dense polygonal meshes with static connectivity. As a result, such deforming meshes often have a tremendous surplus of detail, with many more vertices and polygons than necessary for any given frame. An extensive amount of work has addressed the issue of simplifying a static mesh; however, these methods are inadequate for time-varying surfaces when there is a high degree of non-rigid deformation. We thus propose a new multiresolution representation for deforming surfaces that, together with our dynamic improvement scheme, provides high quality surface approximations at any levelof- detail, for all frames of an animation. Our algorithm also gives rise to a new progressive representation for time-varying multiresolution hierarchies, consisting of a base hierarchy for the initial frame and a sequence of update operations for subsequent frames. We demonstrate that this provides a very effective means of extracting static or view-dependent approximations for a deforming mesh over all frames of an animation.
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    Robust Quasistatic Finite Elements and Flesh Simulation
    (The Eurographics Association, 2005) Teran, Joseph; Sifakis, Eftychios; Irving, Geoffrey; Fedkiw, Ronald; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    Quasistatic and implicit time integration schemes are typically employed to alleviate the stringent time step restrictions imposed by their explicit counterparts. However, both quasistatic and implicit methods are subject to hidden time step restrictions associated with both the prevention of element inversion and the effects of discontinuous contact forces. Furthermore, although fast iterative solvers typically require a symmetric positive definite global stiffness matrix, a number of factors can lead to indefiniteness such as large jumps in boundary conditions, heavy compression, etc. We present a novel quasistatic algorithm that alleviates geometric and material indefiniteness allowing one to use fast conjugate gradient solvers during Newton-Raphson iteration. Additionally, we robustly compute smooth elastic forces in the presence of highly deformed, inverted elements alleviating artificial time step restrictions typically required to prevent such states. Finally, we propose a novel strategy for treating both collision and self-collision in this context.
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    Particle-based Viscoelastic Fluid Simulation
    (The Eurographics Association, 2005) Clavet, Simon; Beaudoin, Philippe; Poulin, Pierre; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    We present a new particle-based method for viscoelastic fluid simulation.We achieve realistic small-scale behavior of substances such as paint or mud as they splash on moving objects. Incompressibility and particle anti-clustering are enforced with a double density relaxation procedure which updates particle positions according to two opposing pressure terms. From this process surface tension effects emerge, enabling drop and filament formation. Elastic and non-linear plastic effects are obtained by adding springs with varying rest length between particles. We also extend the technique to handle interaction between fluid and dynamic objects. Various simulation scenarios are presented including rain drops, fountains, clay manipulation, and floating objects. The method is robust and stable, and can animate splashing behavior at interactive framerates.
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    Simple and efficient compression of animation sequences
    (The Eurographics Association, 2005) Sattler, Mirko; Sarlette, Ralf; Klein, Reinhard; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    We present a new geometry compression method for animations, which is based on the clustered principal component analysis (CPCA). Instead of analyzing the set of vertices for each frame, our method analyzes the set of paths for all vertices for a certain animation length. Thus, using a data-driven approach, it can identify mesh parts, that are "coherent" over time. This usually leads to a very efficient and robust segmentation of the mesh into meaningful clusters, e.g. the wings of a chicken. These parts are then compressed separately using standard principal component analysis (PCA). Each of this clusters can be compressed more efficiently with lesser PCA components compared to previous approaches. Results show, that the new method outperforms other compression schemes like pure PCA based compression or combinations with linear prediction coding, while maintaining a better reconstruction error. This is true, even if the components and weights are quantized before transmission. The reconstruction process is very simple and can be performed directly on the GP.
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    Animosaics
    (The Eurographics Association, 2005) Smithy, Kaleigh; Liuz, Yunjun; Klein, Allison; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    Animated mosaics are a traditional form of stop-motion animation created by arranging and rearranging small objects or tiles from frame to frame. While this animation style is uniquely compelling, the traditional process of manually placing and then moving tiles in each frame is time-consuming and labourious. Recent work has proposed algorithms for static mosaics, but generating temporally coherent mosaic animations has remained open. In addition, previous techniques for temporal coherence allow non-photorealistic primitives to layer, blend, deform, or scale, techniques that are unsuitable for mosaic animations. This paper presents a new approach to temporal coherence and applies this to build a method for creating mosaic animations. Specifically, we characterize temporal coherence as the coordinated movement of groups of primitives. We describe a system for achieving this coordinated movement to create temporally coherent geometric packings of 2D shapes over time. We also show how to create static mosaics comprised of different tile shapes using area-based centroidal Voronoi diagrams
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    Particle-Based Fluid-Fluid Interaction
    (The Eurographics Association, 2005) Müller, Matthias; Solenthaler, Barbara; Keiser, Richard; Gross, Markus; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    The interesting and complex behavior of fluids emerges mainly from interaction processes. While interactions of fluids with static or dynamic solids has caught some attention in computer graphics lately, the mutual interaction of different types of fluids such as air and water or water and wax has received much less attention although these types of interaction are the basis for a variety of important phenomena. In this paper we propose a new technique to model fluid-fluid interaction based on the Smoothed Particle Hydrodynamics (SPH) method. For the simulation of air-water interaction, air particles are generated on the fly only where needed. We also model dynamic phase changes and interface forces. Our technique makes possible the simulation of phenomena such as boiling water, trapped air and the dynamics of a lava lamp.
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    Adapted Unstructured LBM for Flow Simulation on Curved Surfaces
    (The Eurographics Association, 2005) Fan, Z.; Zhao, Y.; Kaufman, A.; He, Y.; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    Flow motion on curved surfaces of arbitrary topology is an interesting visual effect but a complex dynamics to simulate. In this paper, we introduce a novel and effective way to model such dynamics. We propose a technique that adapts a recently emerged computational fluid dynamics (CFD) model, unstructured lattice Boltzmann model (Unstructured LBM), from the 2D unstructured meshes to the 3D surface meshes. Unlike previous methods in modeling flows on surfaces, which start from the macroscopic point of view and modify the Navier Stokes solvers for the curved surfaces, our method is based on the microscopic kinetic equations for discrete particle distribution functions. All computations on the surface mesh only involve the information within local neighborhoods. This model lends itself the following advantages: (i) simplicity and explicit parallelism in computation, (ii) great capability in handling complex interactions, such as the interactions between flow and boundaries and the interactions of multiple-component fluids; (iii) no need of global surface parameterization which may cause strong distortions; (iv) capability of being applied to meshes with arbitrary connectivity.
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    Taming Liquids for Rapidly Changing Targets
    (The Eurographics Association, 2005) Shi, Lin; Yu, Yizhou; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    Following rapidly changing target objects is a challenging problem in fluid control, especially when the natural fluid motion should be preserved. The fluid should be responsive to the changing configuration of the target and, at the same time, its motion should not be overconstrained. In this paper, we introduce an efficient and effective solution by applying two different external force fields. The first one is a feedback force field which compensates for discrepancies in both shape and velocity. Its shape component is designed to be divergence free so that it can survive the velocity projection step. The second one is the gradient field of a potential function defined by the shape and skeletion of the target object. Our experiments indicate a mixture of these two force fields can achieve desirable and pleasing effects.
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    Fast and accurate goal-directed motion synthesis for crowds
    (The Eurographics Association, 2005) Sung, Mankyu; Kovar, Lucas; Gleicher, Michael; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    This paper presents a highly efficient motion synthesis algorithm that is well suited for animating large numbers of characters. Given constraints that require characters to be in specific poses, positions, and orientations in specified time intervals, our algorithm synthesizes motions that exactly satisfy these constraints while avoiding inter-character collisions and collisions with the environment. We represent the space of possible actions with a motion graph and use search algorithms to generate motion. To provide a good initial guess for the search, we employ a fast path planner based on probabilistic roadmaps to navigate characters through complex environments. Also, unlike existing algorithms, our search process allows for smooth, continual adjustments to position, orientation, and timing. This allows us both to satisfy constraints precisely and to generate motion much faster than would otherwise be possible.
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    Behavior Planning for Character Animation
    (The Eurographics Association, 2005) Lau, Manfred; Kuffner, James J.; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    This paper explores a behavior planning approach to automatically generate realistic motions for animated characters. Motion clips are abstracted as high-level behaviors and associated with a behavior finite-state machine (FSM) that defines the movement capabilities of a virtual character. During runtime, motion is generated automatically by a planning algorithm that performs a global search of the FSM and computes a sequence of behaviors for the character to reach a user-designated goal position. Our technique can generate interesting animations using a relatively small amount of data, making it attractive for resource-limited game platforms. It also scales efficiently to large motion databases, because the search performance is primarily dependent on the complexity of the behavior FSM rather than on the amount of data. Heuristic cost functions that the planner uses to evaluate candidate motions provide a flexible framework from which an animator can control character preferences for certain types of behavior. We show results of synthesized animations involving up to one hundred human and animal characters planning simultaneously in both static and dynamic environments.
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    Vortex Fluid for Gaseous Phenomena
    (The Eurographics Association, 2005) Park, Sang Il; Kim, Myoung Jun; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    In this paper, we present a method for visual simulation of gaseous phenomena based on the vortex method. This method uses a localized vortex flow as a basic building block and combines those blocks to describe a whole flow field. As a result, we achieve computational efficiency by concentrating only on a localized vorticity region while generating dynamic swirling fluid flows. Based on the Lagrangian framework, we resolve various boundary conditions. By exploiting the panel method, we satisfy the no-through boundary condition in a Lagrangian way. A simple and effective way of handling the no-slip boundary condition is also presented. In treating the no-slip boundary condition, we allow a user to control the roughness of the boundary surface, which further improves visual realism.
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    Group Motion Graphs
    (The Eurographics Association, 2005) Lai, Yu-Chi; Chenney, Stephen; Fan, Shao Hua; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    We introduce Group Motion Graphs, a data-driven animation technique for groups of discrete agents, such as flocks, herds, or small crowds. Group Motion Graphs are conceptually similar to motion graphs constructed from motion-capture data, but have some important differences: we assume simulated motion; transition nodes are found by clustering group configurations from the input simulations; and clips to join transitions are explicitly constructed via constrained simulation. Graphs built this way offer known bounds on the trajectories that they generate, making it easier to search for particular output motions. The resulting animations show realistic motion at significantly reduced computational cost compared to simulation, and improved control.
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    XFluids in Deforming Meshes
    (The Eurographics Association, 2005) Feldman, Bryan E.; O Brien, James F.; Klingner, Bryan M.; Goktekin, Tolga G.; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    This paper describes a simple modification to an Eulerian fluid simulation that permits the underlying mesh to deform independent of the simulated fluid s motion. The modification consists of a straightforward adaptation of the commonly used semi-Lagrangian advection method to account for the mesh s motion. Because the method does not require more interpolation steps than standard semi-Lagrangian integration, it does not suffer from additional smoothing and requires only the added cost of updating the mesh. By specifying appropriate boundary conditions, mesh boundaries can behave like moving obstacles that act on the fluid resulting in a number of interesting effects. The paper includes several examples that have been computed on moving tetrahedral meshes.
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    Helping Hand: An Anatomically Accurate Inverse Dynamics Solution For Unconstrained Hand Motion
    (The Eurographics Association, 2005) Tsang, Winnie; Singh, Karan; Fiume, Eugene; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    We present a realistic skeletal musculo-tendon model of the human hand and forearm. The model permits direct forward dynamics simulation, which accurately predicts hand and finger position given a set of muscle activations. We also present a solution to the inverse problem of determining an optimal set of muscle activations to achieve a given pose or motion; muscle fatigue, injury or atrophy can also be specified, yielding different control solutions that favour healthy muscle. As there can be many (or no) solutions to this inverse problem, we demonstrate how the space of possible solutions can be filtered to an optimal representative. Of particular note is the ability of our model to take a wide array of joint interdependence into account for both forward and inverse problems. Given kinematic postures, the model can be used to validate, predict or fill in missing motion and improve coarsely specified motion with anatomic fidelity. Lastly, we address the visualization and understanding of the dynamically changing and spatially compact musculature using various interaction techniques.
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    Outside-In Anatomy Based Character Rigging
    (The Eurographics Association, 2005) Pratscher, Michael; Coleman, Patrick; Laszlo, Joe; Singh, Karan; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    For believable character animation, skin deformation should communicate important deformation effects due to underlying muscle movement. Anatomical models that capture these effects are typically constructed from the inside out. Internal tissue is modeled by hand and a surface skin is attached to, or generated from, the internal structure. This paper presents an outside in approach to anatomical modeling, in which we generate musculature from a predefined structure, which we conform to an artist sculpted skin surface. Motivated by interactive applications, we attach the musculature to an existing control skeleton and apply a novel geometric deformation model to deform the skin surface to capture important muscle motion effects. Musculoskeletal structure can be stored as a template and applied to new character models. We illustrate the methodology, as integrated into a commercial character animation system, with examples driven by both keyframe animation and recorded motion data.
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    Physically Based Rigging for Deformable Characters
    (The Eurographics Association, 2005) Capell, Steve; Burkhart, Matthew; Curless, Brian; Duchamp, Tom; Popovic, Zoran; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    In this paper we introduce a framework for instrumenting ( rigging ) characters that are modeled as dynamic elastic bodies, so that their shapes can be controlled by an animator. Because the shape of such a character is determined by physical dynamics, the rigging system cannot simply dictate the shape as in traditional animation. For this reason, we introduce forces as the building blocks of rigging. Rigging forces guide the shape of the character, but are combined with other forces during simulation. Forces have other desirable features: they can be combined easily and simulated at any resolution, and since they are not tightly coupled with the surface geometry, they can be more easily transferred from one model to another. Our framework includes a new pose-dependent linearization scheme for elastic dynamics, which ensures a correspondence between forces and deformations, and at the same time produces plausible results at interactive speeds. We also introduce a novel method of handling collisions around creases.
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    Physically Based Grasping Control from Example
    (The Eurographics Association, 2005) Pollard, Nancy S.; Zordan, Victor B.; D. Terzopoulos and V. Zordan and K. Anjyo and P. Faloutsos
    Animated human characters in everyday scenarios must interact with the environment using their hands. Captured human motion can provide a database of realistic examples. However, examples involving contact are difficult to edit and retarget; realism can suffer when a grasp does not appear secure or when an apparent impact does not disturb the hand or the object. Physically based simulations can preserve plausibility through simulating interaction forces. However, such physical models must be driven by a controller, and creating effective controllers for new motion tasks remains a challenge. In this paper, we present a controller for physically based grasping that draws from motion capture data. Our controller explicitly includes passive and active components to uphold compliant yet controllable motion, and it adds compensation for movement of the arm and for gravity to make the behavior of passive and active components less dependent on the dynamics of arm motion. Given a set of motion capture grasp examples, our system solves for all but a small set of parameters for this controller automatically. We demonstrate results for tasks including grasping and two-hand interaction and show that a controller derived from a single motion capture example can be used to form grasps of different object geometries.