---
OA_place: repository
OA_type: green
_id: '21737'
abstract:
- lang: eng
  text: In calculus, l'Hopital's rule provides a simple way to evaluate the limits
    of quotient functions when both the numerator and denominator vanish. But what
    happens when we move beyond real functions on a real interval? In this article,
    we study when the quotient of two complex-valued functions in higher dimension
    can be defined continuously at the points where both functions vanish. Surprisingly,
    the answer is far subtler than in the real-valued setting. We provide a complete
    characterization for the continuity of the quotient function. We also point out
    why extending this result to smoother quotients remains an intriguing challenge.
acknowledgement: "This project was funded in part by the European Research Council
  (ERC Consolidator Grant 101045083 CoDiNA) and the National Science Foundation CAREER
  Award 2239062.\r\n"
article_number: '2602.09958'
article_processing_charge: No
arxiv: 1
author:
- first_name: Albert
  full_name: Chern, Albert
  last_name: Chern
- first_name: Sadashige
  full_name: Ishida, Sadashige
  id: 6F7C4B96-A8E9-11E9-A7CA-09ECE5697425
  last_name: Ishida
  orcid: 0000-0002-3121-3100
citation:
  ama: Chern A, Ishida S. L’Hopital rules for complex-valued functions in higher dimensions.
    <i>arXiv</i>. doi:<a href="https://doi.org/10.48550/ARXIV.2602.09958">10.48550/ARXIV.2602.09958</a>
  apa: Chern, A., &#38; Ishida, S. (n.d.). L’Hopital rules for complex-valued functions
    in higher dimensions. <i>arXiv</i>. <a href="https://doi.org/10.48550/ARXIV.2602.09958">https://doi.org/10.48550/ARXIV.2602.09958</a>
  chicago: Chern, Albert, and Sadashige Ishida. “L’Hopital Rules for Complex-Valued
    Functions in Higher Dimensions.” <i>ArXiv</i>, n.d. <a href="https://doi.org/10.48550/ARXIV.2602.09958">https://doi.org/10.48550/ARXIV.2602.09958</a>.
  ieee: A. Chern and S. Ishida, “L’Hopital rules for complex-valued functions in higher
    dimensions,” <i>arXiv</i>. .
  ista: Chern A, Ishida S. L’Hopital rules for complex-valued functions in higher
    dimensions. arXiv, 2602.09958.
  mla: Chern, Albert, and Sadashige Ishida. “L’Hopital Rules for Complex-Valued Functions
    in Higher Dimensions.” <i>ArXiv</i>, 2602.09958, doi:<a href="https://doi.org/10.48550/ARXIV.2602.09958">10.48550/ARXIV.2602.09958</a>.
  short: A. Chern, S. Ishida, ArXiv (n.d.).
corr_author: '1'
date_created: 2026-04-15T16:28:24Z
date_published: 2026-02-10T00:00:00Z
date_updated: 2026-04-28T10:56:30Z
day: '10'
ddc:
- '510'
department:
- _id: GradSch
- _id: ChWo
doi: 10.48550/ARXIV.2602.09958
external_id:
  arxiv:
  - '2602.09958'
file:
- access_level: open_access
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  date_created: 2026-04-28T10:53:27Z
  date_updated: 2026-04-28T10:53:27Z
  file_id: '21771'
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  file_size: 867109
  relation: main_file
  success: 1
file_date_updated: 2026-04-28T10:53:27Z
has_accepted_license: '1'
keyword:
- l’Hopital theorem
- complex functions
language:
- iso: eng
month: '02'
oa: 1
oa_version: Preprint
project:
- _id: 34bc2376-11ca-11ed-8bc3-9a3b3961a088
  grant_number: '101045083'
  name: Computational Discovery of Numerical Algorithms for Animation and Simulation
    of Natural Phenomena
publication: arXiv
publication_status: submitted
status: public
title: L'Hopital rules for complex-valued functions in higher dimensions
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: preprint
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2026'
...
---
OA_place: publisher
OA_type: hybrid
PlanS_conform: '1'
_id: '21743'
abstract:
- lang: eng
  text: We present symplectic structures on the shape space of unparameterized space
    curves that generalize the classical Marsden–Weinstein structure. Our method integrates
    the Liouville 1-form of the Marsden–Weinstein structure with Riemannian structures
    that have been introduced in mathematical shape analysis. We also derive Hamiltonian
    vector fields for several classical Hamiltonian functions with respect to these
    new symplectic structures.
acknowledgement: The authors are grateful to Boris Khesin for valuable comments on
  the MW symplectic structure and S. Ishida thanks Albert Chern for insightful discussions
  on space curves and Chris Wojtan for his continuous support. M. Bauer was partially
  supported by NSF grant DMS-1953244 and by the Binational Science Foundation (BSF).
  S. Ishida was partially supported by ERC Consolidator Grant 101045083 “CoDiNA” funded
  by the European Research Council. Some figures were generated by the software Houdini
  and its education license was provided by SideFX. Open access funding provided by
  University of Vienna.
article_number: '45'
article_processing_charge: Yes (via OA deal)
article_type: original
arxiv: 1
author:
- first_name: Martin
  full_name: Bauer, Martin
  last_name: Bauer
- first_name: Sadashige
  full_name: Ishida, Sadashige
  id: 6F7C4B96-A8E9-11E9-A7CA-09ECE5697425
  last_name: Ishida
  orcid: 0000-0002-3121-3100
- first_name: Peter W.
  full_name: Michor, Peter W.
  last_name: Michor
citation:
  ama: Bauer M, Ishida S, Michor PW. Symplectic structures on the space of space curves.
    <i>Journal of Nonlinear Science</i>. 2026;36(2). doi:<a href="https://doi.org/10.1007/s00332-026-10266-8">10.1007/s00332-026-10266-8</a>
  apa: Bauer, M., Ishida, S., &#38; Michor, P. W. (2026). Symplectic structures on
    the space of space curves. <i>Journal of Nonlinear Science</i>. Springer Nature.
    <a href="https://doi.org/10.1007/s00332-026-10266-8">https://doi.org/10.1007/s00332-026-10266-8</a>
  chicago: Bauer, Martin, Sadashige Ishida, and Peter W. Michor. “Symplectic Structures
    on the Space of Space Curves.” <i>Journal of Nonlinear Science</i>. Springer Nature,
    2026. <a href="https://doi.org/10.1007/s00332-026-10266-8">https://doi.org/10.1007/s00332-026-10266-8</a>.
  ieee: M. Bauer, S. Ishida, and P. W. Michor, “Symplectic structures on the space
    of space curves,” <i>Journal of Nonlinear Science</i>, vol. 36, no. 2. Springer
    Nature, 2026.
  ista: Bauer M, Ishida S, Michor PW. 2026. Symplectic structures on the space of
    space curves. Journal of Nonlinear Science. 36(2), 45.
  mla: Bauer, Martin, et al. “Symplectic Structures on the Space of Space Curves.”
    <i>Journal of Nonlinear Science</i>, vol. 36, no. 2, 45, Springer Nature, 2026,
    doi:<a href="https://doi.org/10.1007/s00332-026-10266-8">10.1007/s00332-026-10266-8</a>.
  short: M. Bauer, S. Ishida, P.W. Michor, Journal of Nonlinear Science 36 (2026).
date_created: 2026-04-16T07:29:17Z
date_published: 2026-04-15T00:00:00Z
date_updated: 2026-04-28T09:59:01Z
day: '15'
ddc:
- '510'
department:
- _id: GradSch
- _id: ChWo
doi: 10.1007/s00332-026-10266-8
external_id:
  arxiv:
  - '2407.19908'
file:
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file_date_updated: 2026-04-28T09:55:32Z
has_accepted_license: '1'
intvolume: '        36'
issue: '2'
language:
- iso: eng
month: '04'
oa: 1
oa_version: Published Version
project:
- _id: 34bc2376-11ca-11ed-8bc3-9a3b3961a088
  grant_number: '101045083'
  name: Computational Discovery of Numerical Algorithms for Animation and Simulation
    of Natural Phenomena
publication: Journal of Nonlinear Science
publication_identifier:
  eissn:
  - 1432-1467
  issn:
  - 0938-8974
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
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scopus_import: '1'
status: public
title: Symplectic structures on the space of space curves
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 36
year: '2026'
...
---
OA_place: repository
OA_type: green
_id: '21921'
abstract:
- lang: eng
  text: "A variety of problems in geometry processing boil down to finding the most\r\nparallel
    field relative to a connection. Instances of this prototypical problem\r\nshow
    up in computing direction fields and stripe patterns, quadrilateral\r\nmeshing,
    and visualization of fluid flows. When the class of allowed fields\r\nincludes
    those with topological defects, a relaxation is required to make\r\nthe problem
    well-posed. We observe that these problems can be viewed\r\nas synchronization
    problems, which admit a natural semidefinite relaxation.\r\nWe propose a unified
    method of solving all these problems via the efficient\r\nBurer-Monteiro factorization
    method. Geometrically, this amounts to lifting the field values to a higher-dimensional
    manifold, naturally resolving\r\nthe singular nature of defects. Practically,
    we show that our convex relaxation method achieves better and more reliable optima
    than previous work\r\nemploying alternative relaxations"
acknowledgement: "The authors thank Steven J. Gortler and Nicolas Boumal for interesting
  discussions.\r\nDavid Palmer acknowledges the generous support of the NSF\r\nMSPRF
  under award #2303403 during his time at Harvard University.\r\nNatalia Pacheco-Tallaj
  was supported by the NSF DGE-2141064.\r\nMattéo Couplet was supported by Wallonie-Bruxelles
  International"
article_processing_charge: No
author:
- first_name: Natalia
  full_name: Pacheco-Tallaj, Natalia
  last_name: Pacheco-Tallaj
- first_name: Matteo
  full_name: Couplet, Matteo
  last_name: Couplet
- first_name: Edward
  full_name: Chien, Edward
  last_name: Chien
- first_name: David
  full_name: Palmer, David
  id: 6574708f-2fd3-11f0-89e2-ae42ebc712a4
  last_name: Palmer
  orcid: 0000-0002-1931-5673
citation:
  ama: 'Pacheco-Tallaj N, Couplet M, Chien E, Palmer D. Synchronizing fields with
    singularities. In: <i>SIGGRAPH Conference Papers</i>. ACM. doi:<a href="https://doi.org/10.1145/3799902.3811225">10.1145/3799902.3811225</a>'
  apa: 'Pacheco-Tallaj, N., Couplet, M., Chien, E., &#38; Palmer, D. (n.d.). Synchronizing
    fields with singularities. In <i>SIGGRAPH Conference Papers</i>. Los Angeles,
    CA, United States: ACM. <a href="https://doi.org/10.1145/3799902.3811225">https://doi.org/10.1145/3799902.3811225</a>'
  chicago: Pacheco-Tallaj, Natalia, Matteo Couplet, Edward Chien, and David Palmer.
    “Synchronizing Fields with Singularities.” In <i>SIGGRAPH Conference Papers</i>.
    ACM, n.d. <a href="https://doi.org/10.1145/3799902.3811225">https://doi.org/10.1145/3799902.3811225</a>.
  ieee: N. Pacheco-Tallaj, M. Couplet, E. Chien, and D. Palmer, “Synchronizing fields
    with singularities,” in <i>SIGGRAPH Conference Papers</i>, Los Angeles, CA, United
    States.
  ista: 'Pacheco-Tallaj N, Couplet M, Chien E, Palmer D. Synchronizing fields with
    singularities. SIGGRAPH Conference Papers. SIGGRAPH: International Conference
    and Exhibition on Computer Graphics and Interactive Techniques.'
  mla: Pacheco-Tallaj, Natalia, et al. “Synchronizing Fields with Singularities.”
    <i>SIGGRAPH Conference Papers</i>, ACM, doi:<a href="https://doi.org/10.1145/3799902.3811225">10.1145/3799902.3811225</a>.
  short: N. Pacheco-Tallaj, M. Couplet, E. Chien, D. Palmer, in:, SIGGRAPH Conference
    Papers, ACM, n.d.
conference:
  end_date: 2026-07-23
  location: Los Angeles, CA, United States
  name: 'SIGGRAPH: International Conference and Exhibition on Computer Graphics and
    Interactive Techniques'
  start_date: 2026-07-19
corr_author: '1'
date_created: 2026-05-29T12:53:59Z
date_published: 2026-06-01T00:00:00Z
date_updated: 2026-06-02T06:26:52Z
day: '01'
ddc:
- '000'
department:
- _id: ChWo
doi: 10.1145/3799902.3811225
file:
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file_date_updated: 2026-05-29T12:53:25Z
has_accepted_license: '1'
language:
- iso: eng
month: '06'
oa: 1
oa_version: Accepted Version
publication: SIGGRAPH Conference Papers
publication_identifier:
  eisbn:
  - '9798400725548'
publication_status: accepted
publisher: ACM
quality_controlled: '1'
status: public
title: Synchronizing fields with singularities
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2026'
...
---
OA_place: publisher
OA_type: hybrid
_id: '21923'
abstract:
- lang: eng
  text: "The appearance of simulated natural phenomena heavily depends on the way
    surfaces are textured. However, applying texture maps to dynamic deformable surfaces
    presents a significant challenge, due to ever-shifting differences in length scales
    involved. When these surfaces move and advect the texture along with them, their
    final appearance degrades as deformed regions dramatically distort their texture
    map. Modifications to the texture directly at the pixel level in response to the
    deformation may introduce ghosting artifacts and look unnatural. In the real world,
    the appearance of surface details on a deforming material changes through the
    interplay of physical processes such as rupturing, exposure of internal structure,
    or wrinkling. Motivated by these behaviors, in this work we explore how physical
    principles can guide the texturing methods based on the measure of surface deformation.\r\nWe
    present two novel wave-based procedural texturing algorithms which reproduce common
    physical properties like advection and self-similarity, enabling the plausible
    animation of deforming objects with extreme texture map distortions. Our algorithms
    are fully procedural, require no actual physics simulation, and store no state
    or history of deformation besides the input UV map, making them highly parallelizable
    on the GPU and efficient enough for real-time applications. We show the versatility
    of the method by animating physical phenomena with extreme deformations such as
    flowing lava, stretching putty and outpouring sludge."
acknowledged_ssus:
- _id: ScienComp
acknowledgement: "We thank the anonymous reviewers for their helpful comments, the
  members of the Visual Computing Group at ISTA for their feedback. We also thank
  Jonathan Gagnon for their help with running the Lapped Textures codes and SideFX
  for the Houdini Education software licenses.\r\nImages in Fig. 2 by Kisoulou and
  Vultured on Unsplash, Michal Jarmoluk and Public Domain Pictures from Pixabay and
  Hawai‘i Volcanoes NPS on flickr. This research was supported by the Scientific Service
  Units (SSU) of ISTA through resources provided by Scientific Computing and was funded
  in part by the European Union (ERC-2021-COG 101045083 CoDiNA)."
article_number: '154'
article_processing_charge: Yes
article_type: original
author:
- first_name: Aleksei
  full_name: Kalinov, Aleksei
  id: 44b7120e-eb97-11eb-a6c2-e1557aa81d02
  last_name: Kalinov
  orcid: 0000-0003-2189-3904
- first_name: Mickaël
  full_name: Ly, Mickaël
  id: 6340d7f0-b48d-11eb-b10d-b7487e71d9f1
  last_name: Ly
- first_name: Christian
  full_name: Hafner, Christian
  id: 400429CC-F248-11E8-B48F-1D18A9856A87
  last_name: Hafner
- first_name: Christopher J
  full_name: Wojtan, Christopher J
  id: 3C61F1D2-F248-11E8-B48F-1D18A9856A87
  last_name: Wojtan
  orcid: 0000-0001-6646-5546
citation:
  ama: Kalinov A, Ly M, Hafner C, Wojtan C. Physics-inspired procedural texturing
    of extremely deformable surfaces. <i>ACM Transactions on Graphics</i>. 45(4).
    doi:<a href="https://doi.org/10.1145/3811353">10.1145/3811353</a>
  apa: 'Kalinov, A., Ly, M., Hafner, C., &#38; Wojtan, C. (n.d.). Physics-inspired
    procedural texturing of extremely deformable surfaces. <i>ACM Transactions on
    Graphics</i>. Los Angeles, CA, United States: ACM. <a href="https://doi.org/10.1145/3811353">https://doi.org/10.1145/3811353</a>'
  chicago: Kalinov, Aleksei, Mickaël Ly, Christian Hafner, and Chris Wojtan. “Physics-Inspired
    Procedural Texturing of Extremely Deformable Surfaces.” <i>ACM Transactions on
    Graphics</i>. ACM, n.d. <a href="https://doi.org/10.1145/3811353">https://doi.org/10.1145/3811353</a>.
  ieee: A. Kalinov, M. Ly, C. Hafner, and C. Wojtan, “Physics-inspired procedural
    texturing of extremely deformable surfaces,” <i>ACM Transactions on Graphics</i>,
    vol. 45, no. 4. ACM.
  ista: Kalinov A, Ly M, Hafner C, Wojtan C. Physics-inspired procedural texturing
    of extremely deformable surfaces. ACM Transactions on Graphics. 45(4), 154.
  mla: Kalinov, Aleksei, et al. “Physics-Inspired Procedural Texturing of Extremely
    Deformable Surfaces.” <i>ACM Transactions on Graphics</i>, vol. 45, no. 4, 154,
    ACM, doi:<a href="https://doi.org/10.1145/3811353">10.1145/3811353</a>.
  short: A. Kalinov, M. Ly, C. Hafner, C. Wojtan, ACM Transactions on Graphics 45
    (n.d.).
conference:
  end_date: 2026-07-23
  location: Los Angeles, CA, United States
  name: 'SIGGRAPH: International Conference and Exhibition on Computer Graphics and
    Interactive Techniques'
  start_date: 2026-07-19
corr_author: '1'
date_created: 2026-05-29T13:25:16Z
date_published: 2026-07-01T00:00:00Z
date_updated: 2026-06-02T08:56:50Z
day: '01'
ddc:
- '006'
department:
- _id: GradSch
- _id: ChWo
doi: 10.1145/3811353
file:
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  content_type: video/mp4
  creator: akalinov
  date_created: 2026-05-29T13:19:33Z
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  creator: akalinov
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  file_id: '21926'
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  file_size: 6793867
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  creator: akalinov
  date_created: 2026-05-29T13:19:36Z
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  success: 1
file_date_updated: 2026-05-29T13:19:37Z
has_accepted_license: '1'
intvolume: '        45'
issue: '4'
keyword:
- Procedural animation
language:
- iso: eng
month: '07'
oa: 1
oa_version: Accepted Version
project:
- _id: 34bc2376-11ca-11ed-8bc3-9a3b3961a088
  grant_number: '101045083'
  name: Computational Discovery of Numerical Algorithms for Animation and Simulation
    of Natural Phenomena
publication: ACM Transactions on Graphics
publication_identifier:
  issn:
  - 0730-0301
publication_status: inpress
publisher: ACM
quality_controlled: '1'
status: public
title: Physics-inspired procedural texturing of extremely deformable surfaces
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 45
year: '2026'
...
---
OA_place: publisher
_id: '19630'
abstract:
- lang: eng
  text: "This thesis consists of three chapters, each corresponding to one publication.
    While each of these projects tackles a topic in a different area of research,
    they all share a common thread in the type of topological structure they handle
    - a partition of space into volumes separated by interfaces that meet in non-manifold
    junctions.\r\n\r\nIn Chapter 2, we study clusters of soap bubbles from a simulation
    perspective. In particular, we develop a surface-only algorithm that couples large
    scale motion and shape deformation of soap bubble clusters with the small scale
    evolution of the thin film's thickness, which is responsible for visual phenomena
    like surface vortices, Newton's interference patterns, capillary waves, and deformation-dependent
    rupturing of films in a foam. We model film thickness as a reduced degree of freedom
    in the Navier-Stokes equations and from them derive three sets of equations governing
    normal and tangential motion of the soap film surface, as well as the evolution
    of the thin film thickness. We discretize these equations on a non-manifold triangle
    mesh, extending and adapting operators to handle complex topology. We also present
    an incompressible fluid solver for 2.5D films and an advection algorithm for convecting
    fields across non-manifold surface junctions. Our simulations enhance bubble solvers
    with additional effects caused by convection, rippling, draining, and evaporation
    of the thin film.\r\n\r\nIn Chapter 3, we introduce a multi-material non-manifold
    mesh-based surface tracking algorithm that converts mesh defects, such as overlaps,
    self-intersections, and inversions into topological changes. Our algorithm generalizes
    prior work on manifold surface tracking with topological changes: it preserves
    surface features like mesh-based methods, and it robustly handles topological
    changes like level set methods. Our method also offers improved efficiency and
    robustness over the state of the art. We demonstrate the effectiveness of the
    approach on a range of examples, including complex soap film simulations, such
    as those presented in Chapter 2, but with an order of magnitude more interacting
    bubbles than what we could achieve before, and Boolean unions of non-manifold
    meshes consisting of millions of triangles.\r\n\r\nLastly, in Chapter 4, we utilize
    developments in the theory of random geometric complexes facilitated by observations
    from Discrete Morse theory. We survey the methods and results obtained with this
    new approach, and discuss some of its shortcomings. We use simulations to illustrate
    the results and to form conjectures, getting numerical estimates for combinatorial,
    topological, and geometric properties of weighted and unweighted Delaunay mosaics,
    their dual Voronoi tessellations, and the Alpha and Wrap complexes contained in
    the mosaics."
acknowledged_ssus:
- _id: ScienComp
acknowledgement: The project in Chapter 2 has received funding from the European Research
  Council (ERC) under the European Union's Horizon 2020 research and innovation programme
  under grant agreement No. 638176. The project in Chapter 3 was funded in part by
  the European Union (ERC-2021-COG 101045083 CoDiNA). The project in Chapter 4 has
  received funding from the European Research Council (ERC) under the European Union's
  Horizon 2020 research and innovation programme (grant agreements No 78818 Alpha
  and No 638176). It was also partially supported by the DFG Collaborative Research
  Center TRR 109, 'Discretization in Geometry and Dynamics', through grant no. I02979-N35
  of the Austrian Science Fund (FWF). Thank you for providing funds to support my
  work.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Peter
  full_name: Synak, Peter
  id: 331776E2-F248-11E8-B48F-1D18A9856A87
  last_name: Synak
citation:
  ama: Synak P. Methods for fluid simulation, surface tracking, and statistics of
    non-manifold structures. 2025. doi:<a href="https://doi.org/10.15479/AT-ISTA-19630">10.15479/AT-ISTA-19630</a>
  apa: Synak, P. (2025). <i>Methods for fluid simulation, surface tracking, and statistics
    of non-manifold structures</i>. Institute of Science and Technology Austria. <a
    href="https://doi.org/10.15479/AT-ISTA-19630">https://doi.org/10.15479/AT-ISTA-19630</a>
  chicago: Synak, Peter. “Methods for Fluid Simulation, Surface Tracking, and Statistics
    of Non-Manifold Structures.” Institute of Science and Technology Austria, 2025.
    <a href="https://doi.org/10.15479/AT-ISTA-19630">https://doi.org/10.15479/AT-ISTA-19630</a>.
  ieee: P. Synak, “Methods for fluid simulation, surface tracking, and statistics
    of non-manifold structures,” Institute of Science and Technology Austria, 2025.
  ista: Synak P. 2025. Methods for fluid simulation, surface tracking, and statistics
    of non-manifold structures. Institute of Science and Technology Austria.
  mla: Synak, Peter. <i>Methods for Fluid Simulation, Surface Tracking, and Statistics
    of Non-Manifold Structures</i>. Institute of Science and Technology Austria, 2025,
    doi:<a href="https://doi.org/10.15479/AT-ISTA-19630">10.15479/AT-ISTA-19630</a>.
  short: P. Synak, Methods for Fluid Simulation, Surface Tracking, and Statistics
    of Non-Manifold Structures, Institute of Science and Technology Austria, 2025.
corr_author: '1'
date_created: 2025-04-29T09:39:34Z
date_published: 2025-04-29T00:00:00Z
date_updated: 2026-04-16T08:29:34Z
day: '29'
ddc:
- '519'
- '006'
degree_awarded: PhD
department:
- _id: ChWo
- _id: GradSch
doi: 10.15479/AT-ISTA-19630
ec_funded: 1
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has_accepted_license: '1'
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oa_version: Published Version
page: '106'
project:
- _id: 2533E772-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '638176'
  name: 'Big Splash: Efficient Simulation of Natural Phenomena at Extremely Large
    Scales'
- _id: 34bc2376-11ca-11ed-8bc3-9a3b3961a088
  grant_number: '101045083'
  name: Computational Discovery of Numerical Algorithms for Animation and Simulation
    of Natural Phenomena
- _id: 266A2E9E-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '788183'
  name: Alpha Shape Theory Extended
- _id: 2533E772-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '638176'
  name: 'Big Splash: Efficient Simulation of Natural Phenomena at Extremely Large
    Scales'
- _id: 2561EBF4-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: I02979-N35
  name: Persistence and stability of geometric complexes
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
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supervisor:
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  full_name: Wojtan, Christopher J
  id: 3C61F1D2-F248-11E8-B48F-1D18A9856A87
  last_name: Wojtan
  orcid: 0000-0001-6646-5546
title: Methods for fluid simulation, surface tracking, and statistics of non-manifold
  structures
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
year: '2025'
...
---
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abstract:
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  text: "The space of codimension-2 shapes, such as curves in 3D and surfaces in 4D,
    is an infinite-dimensional manifold. This thesis explores geometric structures
    and dynamics on this space, with emphasis on their implications for physics, particularly
    hydrodynamics.\r\n\r\nOur investigation ranges from theoretical studies of infinite-dimensional
    symplectic and prequantum geometry to numerical computation of the time evolution
    of shapes. The thesis presents four main contributions.\r\n\r\nIn the first part,
    we introduce implicit representations of codimension-2 shapes using a class of
    complex-valued functions, and prove that the space of these implicit representations
    forms a prequantum bundle over the codimension-2 shape space. This reveals a new
    geometric interpretation of the canonical symplectic structure on the codimension-2
    shape space.\r\n\r\nIn the second part, we use implicit representations to develop
    a simulation method for the dynamics of space curves. To handle chaotic systems
    such as vortex filaments in hydrodynamics, we exploit the infinite degrees of
    freedom, hidden in both the configuration and dynamics of implicit representations.\r\n\r\nIn
    the third part, we introduce new symplectic structures on the space of space curves,
    which generalize the only previously known symplectic structure on this space,
    allowing for new Hamiltonian dynamics of space curves.\r\n\r\nIn the fourth part,
    we apply a symplectic viewpoint to a differential geometric problem with practical
    applications. We derive a new area formula for spherical polygons via prequantization. "
acknowledged_ssus:
- _id: CampIT
acknowledgement: "Projects contained in this thesis were financially supported in
  part by the\r\nEuropean Research Council with grants 1. ERC Consolidator Grant 101045083
  CoDiNA,\r\nand 2. the European Union’s Horizon 2020 research and innovation programme
  under grant\r\nagreement No. 638176."
alternative_title:
- ISTA Thesis
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  full_name: Ishida, Sadashige
  id: 6F7C4B96-A8E9-11E9-A7CA-09ECE5697425
  last_name: Ishida
  orcid: 0000-0002-3121-3100
citation:
  ama: Ishida S. Symplectic-prequantum structures and dynamics on the codimension-2
    shape space. 2025. doi:<a href="https://doi.org/10.15479/AT-ISTA-20551">10.15479/AT-ISTA-20551</a>
  apa: Ishida, S. (2025). <i>Symplectic-prequantum structures and dynamics on the
    codimension-2 shape space</i>. Institute of Science and Technology Austria. <a
    href="https://doi.org/10.15479/AT-ISTA-20551">https://doi.org/10.15479/AT-ISTA-20551</a>
  chicago: Ishida, Sadashige. “Symplectic-Prequantum Structures and Dynamics on the
    Codimension-2 Shape Space.” Institute of Science and Technology Austria, 2025.
    <a href="https://doi.org/10.15479/AT-ISTA-20551">https://doi.org/10.15479/AT-ISTA-20551</a>.
  ieee: S. Ishida, “Symplectic-prequantum structures and dynamics on the codimension-2
    shape space,” Institute of Science and Technology Austria, 2025.
  ista: Ishida S. 2025. Symplectic-prequantum structures and dynamics on the codimension-2
    shape space. Institute of Science and Technology Austria.
  mla: Ishida, Sadashige. <i>Symplectic-Prequantum Structures and Dynamics on the
    Codimension-2 Shape Space</i>. Institute of Science and Technology Austria, 2025,
    doi:<a href="https://doi.org/10.15479/AT-ISTA-20551">10.15479/AT-ISTA-20551</a>.
  short: S. Ishida, Symplectic-Prequantum Structures and Dynamics on the Codimension-2
    Shape Space, Institute of Science and Technology Austria, 2025.
corr_author: '1'
date_created: 2025-10-27T10:28:52Z
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project:
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  call_identifier: H2020
  grant_number: '638176'
  name: 'Big Splash: Efficient Simulation of Natural Phenomena at Extremely Large
    Scales'
- _id: 34bc2376-11ca-11ed-8bc3-9a3b3961a088
  grant_number: '101045083'
  name: Computational Discovery of Numerical Algorithms for Animation and Simulation
    of Natural Phenomena
publication_identifier:
  isbn:
  - 978-3-99078-070-1
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
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supervisor:
- first_name: Christopher J
  full_name: Wojtan, Christopher J
  id: 3C61F1D2-F248-11E8-B48F-1D18A9856A87
  last_name: Wojtan
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  full_name: Chern, Albert
  last_name: Chern
title: Symplectic-prequantum structures and dynamics on the codimension-2 shape space
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  short: CC BY (4.0)
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
year: '2025'
...
---
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_id: '20580'
abstract:
- lang: eng
  text: This paper explores the geometry of the space of codimension-2 submanifolds.
    We implicitly represent these submanifolds by a class of complex-valued functions.
    This reveals a prequantum bundle structure over the space of submanifolds, equipped
    with the well-known Marsden-Weinstein symplectic structure. This bundle allows
    a new physical interpretation of the Marsden-Weinstein structure as the curvature
    of a connection form, which measures the average of volumes swept by the deformation
    of the S^1-family of hypersurfaces, defined as the phases of a complex function
    implicitly representing a submanifold.
article_processing_charge: No
arxiv: 1
author:
- first_name: Albert
  full_name: Chern, Albert
  last_name: Chern
- first_name: Sadashige
  full_name: Ishida, Sadashige
  id: 6F7C4B96-A8E9-11E9-A7CA-09ECE5697425
  last_name: Ishida
  orcid: 0000-0002-3121-3100
citation:
  ama: Chern A, Ishida S. Implicit representations of codimension-2 submanifolds and
    their prequantum structure. <i>arXiv</i>. doi:<a href="https://doi.org/10.48550/ARXIV.2507.11727">10.48550/ARXIV.2507.11727</a>
  apa: Chern, A., &#38; Ishida, S. (n.d.). Implicit representations of codimension-2
    submanifolds and their prequantum structure. <i>arXiv</i>. <a href="https://doi.org/10.48550/ARXIV.2507.11727">https://doi.org/10.48550/ARXIV.2507.11727</a>
  chicago: Chern, Albert, and Sadashige Ishida. “Implicit Representations of Codimension-2
    Submanifolds and Their Prequantum Structure.” <i>ArXiv</i>, n.d. <a href="https://doi.org/10.48550/ARXIV.2507.11727">https://doi.org/10.48550/ARXIV.2507.11727</a>.
  ieee: A. Chern and S. Ishida, “Implicit representations of codimension-2 submanifolds
    and their prequantum structure,” <i>arXiv</i>. .
  ista: Chern A, Ishida S. Implicit representations of codimension-2 submanifolds
    and their prequantum structure. arXiv, <a href="https://doi.org/10.48550/ARXIV.2507.11727">10.48550/ARXIV.2507.11727</a>.
  mla: Chern, Albert, and Sadashige Ishida. “Implicit Representations of Codimension-2
    Submanifolds and Their Prequantum Structure.” <i>ArXiv</i>, doi:<a href="https://doi.org/10.48550/ARXIV.2507.11727">10.48550/ARXIV.2507.11727</a>.
  short: A. Chern, S. Ishida, ArXiv (n.d.).
corr_author: '1'
date_created: 2025-10-30T18:36:56Z
date_published: 2025-07-15T00:00:00Z
date_updated: 2026-04-07T12:02:23Z
day: '15'
department:
- _id: GradSch
- _id: ChWo
doi: 10.48550/ARXIV.2507.11727
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- iso: eng
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oa: 1
oa_version: Preprint
publication: arXiv
publication_status: draft
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title: Implicit representations of codimension-2 submanifolds and their prequantum
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tmp:
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...
---
OA_place: publisher
OA_type: hybrid
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abstract:
- lang: eng
  text: "The realistic simulation of sand, soil, powders, rubble piles, and large
    collections of rigid bodies is a common and important problem in the fields of
    computer graphics, computational physics, and engineering. Direct simulation of
    these individual bodies quickly becomes expensive, so we often approximate the
    entire group as a continuum material that can be more easily computed using tools
    for solving partial differential equations, like the material point method (MPM).
    In this paper, we present a method for automatically extracting continuum material
    properties from a collection of rigid\r\nbodies. We use numerical homogenization
    with periodic boundary conditions to simulate an effectively infinite number of
    rigid bodies in contact. We then record the effective stress-strain relationships
    from these simulations and convert them into elastic properties and yield criteria
    for the continuum simulations. Our experiments validate existing theoretical models
    like the Mohr-Coulomb yield surface by extracting material behaviors from a collection
    of spheres in contact. We further generalize these existing models to more exotic
    materials derived from diverse and non-convex shapes. We\r\nobserve complicated
    jamming behaviors from non-convex grains, and we introduce a new material model
    for materials with extremely high levels of internal friction and cohesion. We
    simulate these new continuum models using MPM with an improved return mapping
    technique. The end result is a complete system for turning an input rigid body
    simulation into an efficient continuum simulation with the same effective mechanical
    properties."
acknowledgement: 'We thank the anonymous reviewers for their helpful comments, the
  members of the Visual Computing Group at ISTA for their feedback and Gauthier Rousseau
  for the insightful discussions. This research was supported by the Scientific Service
  Units (SSU) of ISTA through resources provided by Scientific Computing and was funded
  in part by the European Union (ERC-2021-COG 101045083 CoDiNA). '
article_number: '220'
article_processing_charge: Yes (via OA deal)
article_type: original
author:
- first_name: Yi-Lu
  full_name: Chen, Yi-Lu
  id: 0b467602-dbcd-11ea-9d1d-ed480aa46b70
  last_name: Chen
  orcid: 0009-0005-0723-0655
- first_name: Mickaël
  full_name: Ly, Mickaël
  id: 6340d7f0-b48d-11eb-b10d-b7487e71d9f1
  last_name: Ly
- first_name: Christopher J
  full_name: Wojtan, Christopher J
  id: 3C61F1D2-F248-11E8-B48F-1D18A9856A87
  last_name: Wojtan
  orcid: 0000-0001-6646-5546
citation:
  ama: Chen Y-L, Ly M, Wojtan C. Numerical homogenization of sand from grain-level
    simulations. <i>ACM Transactions on Graphics</i>. 2025;44(6). doi:<a href="https://doi.org/10.1145/3763344">10.1145/3763344</a>
  apa: 'Chen, Y.-L., Ly, M., &#38; Wojtan, C. (2025). Numerical homogenization of
    sand from grain-level simulations. <i>ACM Transactions on Graphics</i>. Hong Kong,
    China: Association for Computing Machinery. <a href="https://doi.org/10.1145/3763344">https://doi.org/10.1145/3763344</a>'
  chicago: Chen, Yi-Lu, Mickaël Ly, and Chris Wojtan. “Numerical Homogenization of
    Sand from Grain-Level Simulations.” <i>ACM Transactions on Graphics</i>. Association
    for Computing Machinery, 2025. <a href="https://doi.org/10.1145/3763344">https://doi.org/10.1145/3763344</a>.
  ieee: Y.-L. Chen, M. Ly, and C. Wojtan, “Numerical homogenization of sand from grain-level
    simulations,” <i>ACM Transactions on Graphics</i>, vol. 44, no. 6. Association
    for Computing Machinery, 2025.
  ista: Chen Y-L, Ly M, Wojtan C. 2025. Numerical homogenization of sand from grain-level
    simulations. ACM Transactions on Graphics. 44(6), 220.
  mla: Chen, Yi-Lu, et al. “Numerical Homogenization of Sand from Grain-Level Simulations.”
    <i>ACM Transactions on Graphics</i>, vol. 44, no. 6, 220, Association for Computing
    Machinery, 2025, doi:<a href="https://doi.org/10.1145/3763344">10.1145/3763344</a>.
  short: Y.-L. Chen, M. Ly, C. Wojtan, ACM Transactions on Graphics 44 (2025).
conference:
  end_date: 2025-12-18
  location: Hong Kong, China
  name: 'SIGGRAPH Asia: Conference and Exhibition on Computer Graphics and Interactive
    Techniques in Asia'
  start_date: 2025-12-15
corr_author: '1'
date_created: 2025-11-10T14:12:06Z
date_published: 2025-12-04T00:00:00Z
date_updated: 2025-12-09T14:53:32Z
day: '04'
ddc:
- '531'
- '006'
- '621'
department:
- _id: GradSch
- _id: ChWo
doi: 10.1145/3763344
file:
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  creator: yichen
  date_created: 2025-11-10T14:10:12Z
  date_updated: 2025-11-10T14:10:12Z
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intvolume: '        44'
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month: '12'
oa: 1
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project:
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  grant_number: '101045083'
  name: Computational Discovery of Numerical Algorithms for Animation and Simulation
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publication: ACM Transactions on Graphics
publication_identifier:
  eissn:
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  issn:
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publication_status: published
publisher: Association for Computing Machinery
quality_controlled: '1'
scopus_import: '1'
status: public
title: Numerical homogenization of sand from grain-level simulations
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...
---
OA_place: publisher
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abstract:
- lang: eng
  text: Physics simulation in computer graphics can bring triangle meshes into topologically
    invalid states. The method in this thesis contributed to Heiss-Synak* and Kalinov*
    et al. [2024] who devised a non-manifold hybrid surface tracker—a surface tracker
    that repairs explicit non-manifold triangle meshes with the help of the implicit
    domain. Specifically, this thesis provides an algorithm for filling the holes
    that are left after removing problematic parts of the mesh.
alternative_title:
- ISTA Master's Thesis
article_processing_charge: No
author:
- first_name: Arian
  full_name: Etemadihaghighi, Arian
  id: 36cea3aa-f38e-11ec-8ae0-c65ae6f6098f
  last_name: Etemadihaghighi
citation:
  ama: Etemadi A. Filling the holes of non-manifold self-intersecting meshes for implicit
    topology changes in surface tracking. 2024. doi:<a href="https://doi.org/10.15479/at:ista:18301">10.15479/at:ista:18301</a>
  apa: Etemadi, A. (2024). <i>Filling the holes of non-manifold self-intersecting
    meshes for implicit topology changes in surface tracking</i>. Institute of Science
    and Technology Austria. <a href="https://doi.org/10.15479/at:ista:18301">https://doi.org/10.15479/at:ista:18301</a>
  chicago: Etemadi, Arian. “Filling the Holes of Non-Manifold Self-Intersecting Meshes
    for Implicit Topology Changes in Surface Tracking.” Institute of Science and Technology
    Austria, 2024. <a href="https://doi.org/10.15479/at:ista:18301">https://doi.org/10.15479/at:ista:18301</a>.
  ieee: A. Etemadi, “Filling the holes of non-manifold self-intersecting meshes for
    implicit topology changes in surface tracking,” Institute of Science and Technology
    Austria, 2024.
  ista: Etemadi A. 2024. Filling the holes of non-manifold self-intersecting meshes
    for implicit topology changes in surface tracking. Institute of Science and Technology
    Austria.
  mla: Etemadi, Arian. <i>Filling the Holes of Non-Manifold Self-Intersecting Meshes
    for Implicit Topology Changes in Surface Tracking</i>. Institute of Science and
    Technology Austria, 2024, doi:<a href="https://doi.org/10.15479/at:ista:18301">10.15479/at:ista:18301</a>.
  short: A. Etemadi, Filling the Holes of Non-Manifold Self-Intersecting Meshes for
    Implicit Topology Changes in Surface Tracking, Institute of Science and Technology
    Austria, 2024.
corr_author: '1'
date_created: 2024-10-11T19:52:20Z
date_published: 2024-10-15T00:00:00Z
date_updated: 2026-04-07T13:02:36Z
day: '15'
ddc:
- '000'
degree_awarded: MS
department:
- _id: GradSch
- _id: ChWo
doi: 10.15479/at:ista:18301
file:
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  checksum: 80fb7923e229ad9d39253d7c8a8083d0
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  creator: aetemadi
  date_created: 2024-10-24T14:34:42Z
  date_updated: 2024-10-24T14:34:42Z
  file_id: '18469'
  file_name: thesis-arian-etemadi.pdf
  file_size: 8914218
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  success: 1
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  checksum: 1c02586ed7d441d5ec441867650568d1
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  date_created: 2024-10-24T14:34:54Z
  date_updated: 2024-10-24T14:34:54Z
  file_id: '18470'
  file_name: thesis-arian-etemadi-latex-source.zip
  file_size: 9802650
  relation: source_file
file_date_updated: 2024-10-24T14:34:54Z
has_accepted_license: '1'
keyword:
- surface tracking
- non-manifold
- hole-filling
- topology change
- multi-material
- solid-modeling
language:
- iso: eng
month: '10'
oa: 1
oa_version: Published Version
page: '39'
publication_identifier:
  issn:
  - 2791-4585
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
  record:
  - id: '17219'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Christopher J
  full_name: Wojtan, Christopher J
  id: 3C61F1D2-F248-11E8-B48F-1D18A9856A87
  last_name: Wojtan
  orcid: 0000-0001-6646-5546
title: Filling the holes of non-manifold self-intersecting meshes for implicit topology
  changes in surface tracking
tmp:
  image: /images/cc_by_sa.png
  legal_code_url: https://creativecommons.org/licenses/by-sa/4.0/legalcode
  name: Creative Commons Attribution-ShareAlike 4.0 International Public License (CC
    BY-SA 4.0)
  short: CC BY-SA (4.0)
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
year: '2024'
...
---
OA_place: publisher
OA_type: hybrid
_id: '14703'
abstract:
- lang: eng
  text: We present a discretization of the dynamic optimal transport problem for which
    we can obtain the convergence rate for the value of the transport cost to its
    continuous value when the temporal and spatial stepsize vanish. This convergence
    result does not require any regularity assumption on the measures, though experiments
    suggest that the rate is not sharp. Via an analysis of the duality gap we also
    obtain the convergence rates for the gradient of the optimal potentials and the
    velocity field under mild regularity assumptions. To obtain such rates we discretize
    the dual formulation of the dynamic optimal transport problem and use the mature
    literature related to the error due to discretizing the Hamilton-Jacobi equation.
acknowledgement: 'The authors would like to thank Chris Wojtan for his continuous
  support and several interesting discussions. Part of this research was performed
  during two visits: one of SI to the BIDSA research center at Bocconi University,
  and one of HL to the Institute of Science and Technology Austria. Both host institutions
  are warmly acknowledged for the hospitality. HL is partially supported by the MUR-Prin
  2022-202244A7YL “Gradient Flows and Non-Smooth Geometric Structures with Applications
  to Optimization and Machine Learning”, funded by the European Union - Next Generation
  EU. SI is supported in part by ERC Consolidator Grant 101045083 “CoDiNA” funded
  by the European Research Council.'
article_processing_charge: Yes (via OA deal)
article_type: original
arxiv: 1
author:
- first_name: Sadashige
  full_name: Ishida, Sadashige
  id: 6F7C4B96-A8E9-11E9-A7CA-09ECE5697425
  last_name: Ishida
  orcid: 0000-0002-3121-3100
- first_name: Hugo
  full_name: Lavenant, Hugo
  last_name: Lavenant
citation:
  ama: Ishida S, Lavenant H. Quantitative convergence of a discretization of dynamic
    optimal transport using the dual formulation. <i>Foundations of Computational
    Mathematics</i>. 2024. doi:<a href="https://doi.org/10.1007/s10208-024-09686-3">10.1007/s10208-024-09686-3</a>
  apa: Ishida, S., &#38; Lavenant, H. (2024). Quantitative convergence of a discretization
    of dynamic optimal transport using the dual formulation. <i>Foundations of Computational
    Mathematics</i>. Springer Nature. <a href="https://doi.org/10.1007/s10208-024-09686-3">https://doi.org/10.1007/s10208-024-09686-3</a>
  chicago: Ishida, Sadashige, and Hugo Lavenant. “Quantitative Convergence of a Discretization
    of Dynamic Optimal Transport Using the Dual Formulation.” <i>Foundations of Computational
    Mathematics</i>. Springer Nature, 2024. <a href="https://doi.org/10.1007/s10208-024-09686-3">https://doi.org/10.1007/s10208-024-09686-3</a>.
  ieee: S. Ishida and H. Lavenant, “Quantitative convergence of a discretization of
    dynamic optimal transport using the dual formulation,” <i>Foundations of Computational
    Mathematics</i>. Springer Nature, 2024.
  ista: Ishida S, Lavenant H. 2024. Quantitative convergence of a discretization of
    dynamic optimal transport using the dual formulation. Foundations of Computational
    Mathematics.
  mla: Ishida, Sadashige, and Hugo Lavenant. “Quantitative Convergence of a Discretization
    of Dynamic Optimal Transport Using the Dual Formulation.” <i>Foundations of Computational
    Mathematics</i>, Springer Nature, 2024, doi:<a href="https://doi.org/10.1007/s10208-024-09686-3">10.1007/s10208-024-09686-3</a>.
  short: S. Ishida, H. Lavenant, Foundations of Computational Mathematics (2024).
corr_author: '1'
date_created: 2023-12-21T10:14:37Z
date_published: 2024-11-11T00:00:00Z
date_updated: 2026-06-18T17:37:10Z
day: '11'
ddc:
- '000'
department:
- _id: GradSch
- _id: ChWo
doi: 10.1007/s10208-024-09686-3
external_id:
  arxiv:
  - '2312.12213'
  isi:
  - '001352503300001'
isi: 1
keyword:
- Optimal transport
- Hamilton-Jacobi equation
- convex optimization
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.1007/s10208-024-09686-3
month: '11'
oa: 1
oa_version: Published Version
project:
- _id: 34bc2376-11ca-11ed-8bc3-9a3b3961a088
  grant_number: '101045083'
  name: Computational Discovery of Numerical Algorithms for Animation and Simulation
    of Natural Phenomena
publication: Foundations of Computational Mathematics
publication_identifier:
  eissn:
  - 1615-3383
  issn:
  - 1615-3375
publication_status: epub_ahead
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Quantitative convergence of a discretization of dynamic optimal transport using
  the dual formulation
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2024'
...
---
OA_place: repository
OA_type: green
_id: '12846'
abstract:
- lang: eng
  text: We present a formula for the signed area of a spherical polygon via prequantization.
    In contrast to the traditional formula based on the Gauss-Bonnet theorem that
    requires measuring angles, the new formula mimics Green's theorem and is applicable
    to a wider range of degenerate spherical curves and polygons.
acknowledgement: This work was funded by European Research Council Consolidator grant
  101045083 CoDiNA and National Science Foundation CAREER award 2239062. Some figures
  in the article were generated by the software Houdini and its education license
  was provided by SideFX. The authors acknowledge anonymous referees for their reviews
  and insightful suggestions, and Chris Wojtan for his continuous support through
  discussions. The second author thanks Anna Sisak for a fruitful discussion on prequantum
  bundles.
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Albert
  full_name: Chern, Albert
  last_name: Chern
- first_name: Sadashige
  full_name: Ishida, Sadashige
  id: 6F7C4B96-A8E9-11E9-A7CA-09ECE5697425
  last_name: Ishida
  orcid: 0000-0002-3121-3100
citation:
  ama: Chern A, Ishida S. Area formula for spherical polygons via prequantization.
    <i>SIAM Journal on Applied Algebra and Geometry</i>. 2024;8(3):782-796. doi:<a
    href="https://doi.org/10.1137/23M1565255">10.1137/23M1565255</a>
  apa: Chern, A., &#38; Ishida, S. (2024). Area formula for spherical polygons via
    prequantization. <i>SIAM Journal on Applied Algebra and Geometry</i>. Society
    for Industrial and Applied Mathematics. <a href="https://doi.org/10.1137/23M1565255">https://doi.org/10.1137/23M1565255</a>
  chicago: Chern, Albert, and Sadashige Ishida. “Area Formula for Spherical Polygons
    via Prequantization.” <i>SIAM Journal on Applied Algebra and Geometry</i>. Society
    for Industrial and Applied Mathematics, 2024. <a href="https://doi.org/10.1137/23M1565255">https://doi.org/10.1137/23M1565255</a>.
  ieee: A. Chern and S. Ishida, “Area formula for spherical polygons via prequantization,”
    <i>SIAM Journal on Applied Algebra and Geometry</i>, vol. 8, no. 3. Society for
    Industrial and Applied Mathematics, pp. 782–796, 2024.
  ista: Chern A, Ishida S. 2024. Area formula for spherical polygons via prequantization.
    SIAM Journal on Applied Algebra and Geometry. 8(3), 782–796.
  mla: Chern, Albert, and Sadashige Ishida. “Area Formula for Spherical Polygons via
    Prequantization.” <i>SIAM Journal on Applied Algebra and Geometry</i>, vol. 8,
    no. 3, Society for Industrial and Applied Mathematics, 2024, pp. 782–96, doi:<a
    href="https://doi.org/10.1137/23M1565255">10.1137/23M1565255</a>.
  short: A. Chern, S. Ishida, SIAM Journal on Applied Algebra and Geometry 8 (2024)
    782–796.
corr_author: '1'
date_created: 2023-04-18T19:16:06Z
date_published: 2024-09-23T00:00:00Z
date_updated: 2026-04-07T12:02:22Z
day: '23'
ddc:
- '516'
department:
- _id: GradSch
- _id: ChWo
doi: 10.1137/23M1565255
external_id:
  arxiv:
  - '2303.14555'
  isi:
  - '001342265800009'
has_accepted_license: '1'
intvolume: '         8'
isi: 1
issue: '3'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.48550/arXiv.2303.14555
month: '09'
oa: 1
oa_version: Preprint
page: 782-796
project:
- _id: 34bc2376-11ca-11ed-8bc3-9a3b3961a088
  grant_number: '101045083'
  name: Computational Discovery of Numerical Algorithms for Animation and Simulation
    of Natural Phenomena
publication: SIAM Journal on Applied Algebra and Geometry
publication_identifier:
  eissn:
  - 2470-6566
publication_status: published
publisher: Society for Industrial and Applied Mathematics
quality_controlled: '1'
related_material:
  record:
  - id: '20551'
    relation: dissertation_contains
    status: public
scopus_import: '1'
status: public
title: Area formula for spherical polygons via prequantization
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 8
year: '2024'
...
---
_id: '17203'
abstract:
- lang: eng
  text: "The behavior of a rigid body primarily depends on its mass moments, which
    consist of the mass, center of mass, and moments of inertia. It is possible to
    manipulate these quantities without altering the geometric appearance of an object
    by introducing cavities in its interior. Algorithms that find cavities of suitable
    shapes and sizes have enabled the computational design of spinning tops, yo-yos,
    wheels, buoys, and statically balanced objects. Previous work is based, for example,
    on topology optimization on voxel grids, which introduces a large number of optimization
    variables and box constraints, or offset surface computation, which cannot guarantee
    that solutions to a feasible problem will always be found.\r\n\r\nIn this work,
    we provide a mathematical analysis of constrained topology optimization problems
    that depend only on mass moments. This class of problems covers, among others,
    all applications mentioned above. Our main result is to show that no matter the
    outer shape of the rigid body to be optimized or the optimization objective and
    constraints considered, the optimal solution always features a quadric-shaped
    interface between material and cavities. This proves that optimal interfaces are
    always ellipsoids, hyperboloids, paraboloids, or one of a few degenerate cases,
    such as planes.\r\n\r\nThis insight lets us replace a difficult topology optimization
    problem with a provably equivalent non-linear equation system in a small number
    (<10) of variables, which represent the coefficients of the quadric. This system
    can be solved in a few seconds for most examples, provides insights into the geometric
    structure of many specific applications, and lets us describe their solution properties.
    Finally, our method integrates seamlessly into modern fabrication workflows because
    our solutions are analytical surfaces that are native to the CAD domain."
acknowledgement: We thank Gianmarco Cherchi for his help in tailoring the Mesh Booleans
  code for this project, Stefan Jeschke for his help with the photographs, Malina
  Strugaru and Aleksei Kalinov for their help with the samples, and the anonymous
  reviewers as well as the members of the ISTA Visual Computing Group for their feedback.
  This project was funded in part by the European Research Council (ERC Consolidator
  Grant 101045083 CoDiNA).
article_number: '78'
article_processing_charge: Yes (via OA deal)
article_type: original
author:
- first_name: Christian
  full_name: Hafner, Christian
  id: 400429CC-F248-11E8-B48F-1D18A9856A87
  last_name: Hafner
- first_name: Mickaël
  full_name: Ly, Mickaël
  id: 6340d7f0-b48d-11eb-b10d-b7487e71d9f1
  last_name: Ly
- first_name: Christopher J
  full_name: Wojtan, Christopher J
  id: 3C61F1D2-F248-11E8-B48F-1D18A9856A87
  last_name: Wojtan
  orcid: 0000-0001-6646-5546
citation:
  ama: 'Hafner C, Ly M, Wojtan C. Spin-it faster: Quadrics solve all topology optimization
    problems that depend only on mass moments. <i>Transactions on Graphics</i>. 2024;43(4).
    doi:<a href="https://doi.org/10.1145/3658194">10.1145/3658194</a>'
  apa: 'Hafner, C., Ly, M., &#38; Wojtan, C. (2024). Spin-it faster: Quadrics solve
    all topology optimization problems that depend only on mass moments. <i>Transactions
    on Graphics</i>. Denver, Colorado: Association for Computing Machinery. <a href="https://doi.org/10.1145/3658194">https://doi.org/10.1145/3658194</a>'
  chicago: 'Hafner, Christian, Mickaël Ly, and Chris Wojtan. “Spin-It Faster: Quadrics
    Solve All Topology Optimization Problems That Depend Only on Mass Moments.” <i>Transactions
    on Graphics</i>. Association for Computing Machinery, 2024. <a href="https://doi.org/10.1145/3658194">https://doi.org/10.1145/3658194</a>.'
  ieee: 'C. Hafner, M. Ly, and C. Wojtan, “Spin-it faster: Quadrics solve all topology
    optimization problems that depend only on mass moments,” <i>Transactions on Graphics</i>,
    vol. 43, no. 4. Association for Computing Machinery, 2024.'
  ista: 'Hafner C, Ly M, Wojtan C. 2024. Spin-it faster: Quadrics solve all topology
    optimization problems that depend only on mass moments. Transactions on Graphics.
    43(4), 78.'
  mla: 'Hafner, Christian, et al. “Spin-It Faster: Quadrics Solve All Topology Optimization
    Problems That Depend Only on Mass Moments.” <i>Transactions on Graphics</i>, vol.
    43, no. 4, 78, Association for Computing Machinery, 2024, doi:<a href="https://doi.org/10.1145/3658194">10.1145/3658194</a>.'
  short: C. Hafner, M. Ly, C. Wojtan, Transactions on Graphics 43 (2024).
conference:
  end_date: 2024-08-01
  location: Denver, Colorado
  start_date: 2024-07-28
corr_author: '1'
date_created: 2024-07-05T12:08:57Z
date_published: 2024-07-01T00:00:00Z
date_updated: 2025-09-08T08:29:09Z
day: '01'
ddc:
- '516'
department:
- _id: ChWo
doi: 10.1145/3658194
external_id:
  isi:
  - '001289270900045'
file:
- access_level: open_access
  checksum: 0dc9f5a6422b8a49a79026900f349ee5
  content_type: application/pdf
  creator: chafner
  date_created: 2024-07-05T12:05:17Z
  date_updated: 2024-07-05T12:05:17Z
  file_id: '17204'
  file_name: sif-final.pdf
  file_size: 7225150
  relation: main_file
  success: 1
- access_level: open_access
  checksum: cde433c6a40688d5f1187fb5721f6f94
  content_type: application/pdf
  creator: chafner
  date_created: 2024-07-05T12:06:03Z
  date_updated: 2024-07-05T12:06:03Z
  file_id: '17205'
  file_name: sif-supp-final.pdf
  file_size: 397262
  relation: supplementary_material
- access_level: open_access
  checksum: c0457a09c2ab9a1c2935c995dcc84907
  content_type: video/mp4
  creator: chafner
  date_created: 2024-07-17T09:29:13Z
  date_updated: 2024-07-17T09:29:13Z
  file_id: '17276'
  file_name: sif-video-final.mp4
  file_size: 170001305
  relation: supplementary_material
  title: Submission Video
file_date_updated: 2024-07-17T09:29:13Z
has_accepted_license: '1'
intvolume: '        43'
isi: 1
issue: '4'
keyword:
- Topology Optimization
- Mass Moments
- Computational Geometry
language:
- iso: eng
month: '07'
oa: 1
oa_version: Published Version
project:
- _id: 34bc2376-11ca-11ed-8bc3-9a3b3961a088
  grant_number: '101045083'
  name: Computational Discovery of Numerical Algorithms for Animation and Simulation
    of Natural Phenomena
publication: Transactions on Graphics
publication_identifier:
  eissn:
  - 1557-7368
  issn:
  - 0730-0301
publication_status: published
publisher: Association for Computing Machinery
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'Spin-it faster: Quadrics solve all topology optimization problems that depend
  only on mass moments'
type: journal_article
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 43
year: '2024'
...
---
_id: '17214'
abstract:
- lang: eng
  text: 'Current numerical algorithms for simulating friction fall in one of two camps:
    smooth solvers sacrifice the stable treatment of static friction in exchange for
    fast convergence, and non-smooth solvers accurately compute friction at convergence
    rates that are often prohibitive for large graphics applications. We introduce
    a novel bridge between these two ideas that computes static and dynamic friction
    stably and efficiently. Our key idea is to convert the highly constrained non-smooth
    problem into an unconstrained smooth problem using logarithmic barriers that converges
    to the exact solution as accuracy increases. We phrase the problem as an interior
    point primal-dual problem that can be solved efficiently with Newton iteration.
    We observe quadratic convergence despite the non-smooth nature of the original
    problem, and our method is well-suited for large systems of tightly packed objects
    with many contact points. We demonstrate the efficacy of our method with stable
    piles of grains and stacks of objects, complex granular flows, and robust interlocking
    assemblies of rigid bodies.'
acknowledgement: We thank Vincent Acary for his help with Siconos, as well as the
  anonymous reviewers and the members of the Visual Computing Group at ISTA for their
  helpful comments. This research was funded in part by the European Union (ERC-2021-COG
  101045083 CoDiNA).
article_processing_charge: Yes (via OA deal)
author:
- first_name: Yi-Lu
  full_name: Chen, Yi-Lu
  id: 0b467602-dbcd-11ea-9d1d-ed480aa46b70
  last_name: Chen
- first_name: Mickaël
  full_name: Ly, Mickaël
  id: 6340d7f0-b48d-11eb-b10d-b7487e71d9f1
  last_name: Ly
- first_name: Christopher J
  full_name: Wojtan, Christopher J
  id: 3C61F1D2-F248-11E8-B48F-1D18A9856A87
  last_name: Wojtan
  orcid: 0000-0001-6646-5546
citation:
  ama: 'Chen Y-L, Ly M, Wojtan C. Primal-dual non-smooth friction for rigid body animation.
    In: <i>Special Interest Group on Computer Graphics and Interactive Techniques
    Conference Conference Papers ’24</i>. Association for Computing Machinery; 2024.
    doi:<a href="https://doi.org/10.1145/3641519.3657485">10.1145/3641519.3657485</a>'
  apa: 'Chen, Y.-L., Ly, M., &#38; Wojtan, C. (2024). Primal-dual non-smooth friction
    for rigid body animation. In <i>Special Interest Group on Computer Graphics and
    Interactive Techniques Conference Conference Papers ’24</i>. Denver, United States:
    Association for Computing Machinery. <a href="https://doi.org/10.1145/3641519.3657485">https://doi.org/10.1145/3641519.3657485</a>'
  chicago: Chen, Yi-Lu, Mickaël Ly, and Chris Wojtan. “Primal-Dual Non-Smooth Friction
    for Rigid Body Animation.” In <i>Special Interest Group on Computer Graphics and
    Interactive Techniques Conference Conference Papers ’24</i>. Association for Computing
    Machinery, 2024. <a href="https://doi.org/10.1145/3641519.3657485">https://doi.org/10.1145/3641519.3657485</a>.
  ieee: Y.-L. Chen, M. Ly, and C. Wojtan, “Primal-dual non-smooth friction for rigid
    body animation,” in <i>Special Interest Group on Computer Graphics and Interactive
    Techniques Conference Conference Papers ’24</i>, Denver, United States, 2024.
  ista: 'Chen Y-L, Ly M, Wojtan C. 2024. Primal-dual non-smooth friction for rigid
    body animation. Special Interest Group on Computer Graphics and Interactive Techniques
    Conference Conference Papers ’24. SIGGRAPH: Computer Graphics and Interactive
    Techniques Conference.'
  mla: Chen, Yi-Lu, et al. “Primal-Dual Non-Smooth Friction for Rigid Body Animation.”
    <i>Special Interest Group on Computer Graphics and Interactive Techniques Conference
    Conference Papers ’24</i>, Association for Computing Machinery, 2024, doi:<a href="https://doi.org/10.1145/3641519.3657485">10.1145/3641519.3657485</a>.
  short: Y.-L. Chen, M. Ly, C. Wojtan, in:, Special Interest Group on Computer Graphics
    and Interactive Techniques Conference Conference Papers ’24, Association for Computing
    Machinery, 2024.
conference:
  end_date: 2024-08-01
  location: Denver, United States
  name: 'SIGGRAPH: Computer Graphics and Interactive Techniques Conference'
  start_date: 2024-07-28
corr_author: '1'
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date_updated: 2025-09-08T08:54:38Z
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keyword:
- physical simulation
- frictional contact
- rigid body mechanics
- non-smooth dynamics
language:
- iso: eng
month: '07'
oa: 1
oa_version: Published Version
project:
- _id: 34bc2376-11ca-11ed-8bc3-9a3b3961a088
  grant_number: '101045083'
  name: Computational Discovery of Numerical Algorithms for Animation and Simulation
    of Natural Phenomena
publication: Special Interest Group on Computer Graphics and Interactive Techniques
  Conference Conference Papers '24
publication_identifier:
  isbn:
  - '9798400705250'
publication_status: published
publisher: Association for Computing Machinery
quality_controlled: '1'
scopus_import: '1'
status: public
title: Primal-dual non-smooth friction for rigid body animation
type: conference
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
year: '2024'
...
---
OA_place: publisher
OA_type: hybrid
_id: '17219'
abstract:
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  text: 'We introduce a multi-material non-manifold mesh-based surface tracking algorithm
    that converts self-intersections into topological changes. Our algorithm generalizes
    prior work on manifold surface tracking with topological changes: it preserves
    surface features like mesh-based methods, and it robustly handles topological
    changes like level set methods. Our method also offers improved efficiency and
    robustness over the state of the art. We demonstrate the effectiveness of the
    approach on a range of examples, including complex soap film simulations with
    thousands of interacting bubbles, and boolean unions of non-manifold meshes consisting
    of millions of triangles.'
acknowledgement: Peter Heiss-Synak helped conceive the project, helped formulate the
  algorithm structure, contributed ideas and code to Sections 6 & 8, the mesh data
  structure, algorithm robustness and benchmarks, helped write the paper, and provided
  supervision and conceptual solutions throughout the project. Aleksei Kalinov contributed
  ideas and code to Sections 7, 8.5, and 5, the sparse grid data structure, algorithm
  robustness and benchmarks, optimized the performance, produced all results, most
  figures, and the supplementary video, helped write the text, and provided conceptual
  solutions throughout the project. Malina Strugaru helped implement the mesh data
  structure and designed re-meshing operations for non-manifold triangle meshes. Arian
  Etemadi developed early prototypes for ideas in Sections 8.1 and 8.3 and helped
  write the paper. Huidong Yang developed early prototypes for isosurface extraction
  and visualization. Chris Wojtan helped conceive the project, helped write the paper,
  and provided supervision, prototype grid data structure code, and conceptual solutions
  throughout the project. We thank the anonymous reviewers for their helpful comments,
  the members of the Visual Computing Group at ISTA for their feedback, Christopher
  Batty for discussions about LosTopos, and SideFX for the Houdini Education software
  licenses.  This research was funded in part by the European Union (ERC-2021-COG
  101045083 CoDiNA).
article_number: '54'
article_processing_charge: Yes (via OA deal)
article_type: original
author:
- first_name: Peter
  full_name: Synak, Peter
  id: 331776E2-F248-11E8-B48F-1D18A9856A87
  last_name: Synak
- first_name: Aleksei
  full_name: Kalinov, Aleksei
  id: 44b7120e-eb97-11eb-a6c2-e1557aa81d02
  last_name: Kalinov
  orcid: 0000-0003-2189-3904
- first_name: Irina-Malina
  full_name: Strugaru, Irina-Malina
  id: 2afc607f-f128-11eb-9611-8f2a0dfcf074
  last_name: Strugaru
- first_name: Arian
  full_name: Etemadihaghighi, Arian
  id: 36cea3aa-f38e-11ec-8ae0-c65ae6f6098f
  last_name: Etemadihaghighi
- first_name: Huidong
  full_name: Yang, Huidong
  last_name: Yang
- first_name: Christopher J
  full_name: Wojtan, Christopher J
  id: 3C61F1D2-F248-11E8-B48F-1D18A9856A87
  last_name: Wojtan
  orcid: 0000-0001-6646-5546
citation:
  ama: Synak P, Kalinov A, Strugaru I-M, Etemadi A, Yang H, Wojtan C. Multi-material
    mesh-based surface tracking with implicit topology changes. <i>ACM Transactions
    on Graphics</i>. 2024;43(4). doi:<a href="https://doi.org/10.1145/3658223">10.1145/3658223</a>
  apa: Synak, P., Kalinov, A., Strugaru, I.-M., Etemadi, A., Yang, H., &#38; Wojtan,
    C. (2024). Multi-material mesh-based surface tracking with implicit topology changes.
    <i>ACM Transactions on Graphics</i>. Association for Computing Machinery. <a href="https://doi.org/10.1145/3658223">https://doi.org/10.1145/3658223</a>
  chicago: Synak, Peter, Aleksei Kalinov, Irina-Malina Strugaru, Arian Etemadi, Huidong
    Yang, and Chris Wojtan. “Multi-Material Mesh-Based Surface Tracking with Implicit
    Topology Changes.” <i>ACM Transactions on Graphics</i>. Association for Computing
    Machinery, 2024. <a href="https://doi.org/10.1145/3658223">https://doi.org/10.1145/3658223</a>.
  ieee: P. Synak, A. Kalinov, I.-M. Strugaru, A. Etemadi, H. Yang, and C. Wojtan,
    “Multi-material mesh-based surface tracking with implicit topology changes,” <i>ACM
    Transactions on Graphics</i>, vol. 43, no. 4. Association for Computing Machinery,
    2024.
  ista: Synak P, Kalinov A, Strugaru I-M, Etemadi A, Yang H, Wojtan C. 2024. Multi-material
    mesh-based surface tracking with implicit topology changes. ACM Transactions on
    Graphics. 43(4), 54.
  mla: Synak, Peter, et al. “Multi-Material Mesh-Based Surface Tracking with Implicit
    Topology Changes.” <i>ACM Transactions on Graphics</i>, vol. 43, no. 4, 54, Association
    for Computing Machinery, 2024, doi:<a href="https://doi.org/10.1145/3658223">10.1145/3658223</a>.
  short: P. Synak, A. Kalinov, I.-M. Strugaru, A. Etemadi, H. Yang, C. Wojtan, ACM
    Transactions on Graphics 43 (2024).
corr_author: '1'
date_created: 2024-07-10T12:24:00Z
date_published: 2024-07-01T00:00:00Z
date_updated: 2026-04-07T13:02:36Z
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- _id: ChWo
doi: 10.1145/3658223
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has_accepted_license: '1'
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isi: 1
issue: '4'
keyword:
- surface tracking
- topology change
- non- manifold meshes
- multi-material flows
- solid modeling
language:
- iso: eng
license: https://creativecommons.org/licenses/by-nc-sa/4.0/
month: '07'
oa: 1
oa_version: Published Version
project:
- _id: 34bc2376-11ca-11ed-8bc3-9a3b3961a088
  grant_number: '101045083'
  name: Computational Discovery of Numerical Algorithms for Animation and Simulation
    of Natural Phenomena
publication: ACM Transactions on Graphics
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  issn:
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publication_status: published
publisher: Association for Computing Machinery
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title: Multi-material mesh-based surface tracking with implicit topology changes
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---
OA_place: repository
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abstract:
- lang: eng
  text: We present symplectic structures on the shape space of unparameterized space
    curves that generalize the classical Marsden-Weinstein structure. Our method integrates
    the Liouville 1-form of the Marsden-Weinstein structure with Riemannian structures
    that have been introduced in mathematical shape analysis. We also derive Hamiltonian
    vector fields for several classical Hamiltonian functions with respect to these
    new symplectic structures.
acknowledgement: The authors are grateful to Boris Khesin for valuable comments on
  the MW symplectic structure and S. Ishida thanks Albert Chern for insightful discussions
  on space curves and Chris Wojtan for his continuous support. M. Bauer was partially
  supported by NSF grant DMS-1953244 and by the Binational Science Foundation (BSF).
  S. Ishida was partially supported by ERC Consolidator Grant 101045083 “CoDiNA” funded
  by the European Research Council. Some figures were generated by the software Houdini
  and its education license was provided by SideFX.
article_processing_charge: No
arxiv: 1
author:
- first_name: Martin
  full_name: Bauer, Martin
  last_name: Bauer
- first_name: Sadashige
  full_name: Ishida, Sadashige
  id: 6F7C4B96-A8E9-11E9-A7CA-09ECE5697425
  last_name: Ishida
  orcid: 0000-0002-3121-3100
- first_name: Peter W.
  full_name: Michor, Peter W.
  last_name: Michor
citation:
  ama: Bauer M, Ishida S, Michor PW. Symplectic structures on the space of space curves.
    <i>arXiv</i>. doi:<a href="https://doi.org/10.48550/arXiv.2407.19908">10.48550/arXiv.2407.19908</a>
  apa: Bauer, M., Ishida, S., &#38; Michor, P. W. (n.d.). Symplectic structures on
    the space of space curves. <i>arXiv</i>. <a href="https://doi.org/10.48550/arXiv.2407.19908">https://doi.org/10.48550/arXiv.2407.19908</a>
  chicago: Bauer, Martin, Sadashige Ishida, and Peter W. Michor. “Symplectic Structures
    on the Space of Space Curves.” <i>ArXiv</i>, n.d. <a href="https://doi.org/10.48550/arXiv.2407.19908">https://doi.org/10.48550/arXiv.2407.19908</a>.
  ieee: M. Bauer, S. Ishida, and P. W. Michor, “Symplectic structures on the space
    of space curves,” <i>arXiv</i>. .
  ista: Bauer M, Ishida S, Michor PW. Symplectic structures on the space of space
    curves. arXiv, <a href="https://doi.org/10.48550/arXiv.2407.19908">10.48550/arXiv.2407.19908</a>.
  mla: Bauer, Martin, et al. “Symplectic Structures on the Space of Space Curves.”
    <i>ArXiv</i>, doi:<a href="https://doi.org/10.48550/arXiv.2407.19908">10.48550/arXiv.2407.19908</a>.
  short: M. Bauer, S. Ishida, P.W. Michor, ArXiv (n.d.).
date_created: 2024-08-01T06:34:08Z
date_published: 2024-07-29T00:00:00Z
date_updated: 2026-04-28T09:59:01Z
day: '29'
department:
- _id: GradSch
- _id: ChWo
doi: 10.48550/arXiv.2407.19908
external_id:
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  - '2407.19908'
keyword:
- space of space curves
- symplectic stuctures
language:
- iso: eng
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oa_version: Preprint
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  grant_number: '101045083'
  name: Computational Discovery of Numerical Algorithms for Animation and Simulation
    of Natural Phenomena
publication: arXiv
publication_status: draft
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...
---
_id: '14628'
abstract:
- lang: eng
  text: We introduce a compact, intuitive procedural graph representation for cellular
    metamaterials, which are small-scale, tileable structures that can be architected
    to exhibit many useful material properties. Because the structures’ “architectures”
    vary widely—with elements such as beams, thin shells, and solid bulks—it is difficult
    to explore them using existing representations. Generic approaches like voxel
    grids are versatile, but it is cumbersome to represent and edit individual structures;
    architecture-specific approaches address these issues, but are incompatible with
    one another. By contrast, our procedural graph succinctly represents the construction
    process for any structure using a simple skeleton annotated with spatially varying
    thickness. To express the highly constrained triply periodic minimal surfaces
    (TPMS) in this manner, we present the first fully automated version of the conjugate
    surface construction method, which allows novices to create complex TPMS from
    intuitive input. We demonstrate our representation’s expressiveness, accuracy,
    and compactness by constructing a wide range of established structures and hundreds
    of novel structures with diverse architectures and material properties. We also
    conduct a user study to verify our representation’s ease-of-use and ability to
    expand engineers’ capacity for exploration.
acknowledgement: "The authors thank Mina Konaković Luković and Michael Foshey for
  their early contributions to this project, David Palmer and Paul Zhang for their
  insightful discussions about minimal surfaces and the CSCM, Julian Panetta for providing
  the Elastic Textures code, and Hannes Hergeth for his feedback and support. We also
  thank our user study participants and anonymous reviewers.\r\nThis material is based
  upon work supported by the National Science Foundation\r\n(NSF) Graduate Research
  Fellowship under Grant No. 2141064; the MIT Morningside\r\nAcademy for Design Fellowship;
  the Defense Advanced Research Projects Agency\r\n(DARPA) Grant No. FA8750-20-C-0075;
  the ERC Consolidator Grant No. 101045083,\r\n“CoDiNA: Computational Discovery of
  Numerical Algorithms for Animation and Simulation of Natural Phenomena”; and the
  NewSat project, which is co-funded by the Operational Program for Competitiveness
  and Internationalisation (COMPETE2020), Portugal 2020, the European Regional Development
  Fund (ERDF), and the Portuguese Foundation for Science and Technology (FTC) under
  the MIT Portugal program."
article_number: '168'
article_processing_charge: Yes (in subscription journal)
article_type: original
author:
- first_name: Liane
  full_name: Makatura, Liane
  last_name: Makatura
- first_name: Bohan
  full_name: Wang, Bohan
  last_name: Wang
- first_name: Yi-Lu
  full_name: Chen, Yi-Lu
  id: 0b467602-dbcd-11ea-9d1d-ed480aa46b70
  last_name: Chen
- first_name: Bolei
  full_name: Deng, Bolei
  last_name: Deng
- first_name: Christopher J
  full_name: Wojtan, Christopher J
  id: 3C61F1D2-F248-11E8-B48F-1D18A9856A87
  last_name: Wojtan
  orcid: 0000-0001-6646-5546
- first_name: Bernd
  full_name: Bickel, Bernd
  id: 49876194-F248-11E8-B48F-1D18A9856A87
  last_name: Bickel
  orcid: 0000-0001-6511-9385
- first_name: Wojciech
  full_name: Matusik, Wojciech
  last_name: Matusik
citation:
  ama: 'Makatura L, Wang B, Chen Y-L, et al. Procedural metamaterials: A unified procedural
    graph for metamaterial design. <i>ACM Transactions on Graphics</i>. 2023;42(5).
    doi:<a href="https://doi.org/10.1145/3605389">10.1145/3605389</a>'
  apa: 'Makatura, L., Wang, B., Chen, Y.-L., Deng, B., Wojtan, C., Bickel, B., &#38;
    Matusik, W. (2023). Procedural metamaterials: A unified procedural graph for metamaterial
    design. <i>ACM Transactions on Graphics</i>. Association for Computing Machinery.
    <a href="https://doi.org/10.1145/3605389">https://doi.org/10.1145/3605389</a>'
  chicago: 'Makatura, Liane, Bohan Wang, Yi-Lu Chen, Bolei Deng, Chris Wojtan, Bernd
    Bickel, and Wojciech Matusik. “Procedural Metamaterials: A Unified Procedural
    Graph for Metamaterial Design.” <i>ACM Transactions on Graphics</i>. Association
    for Computing Machinery, 2023. <a href="https://doi.org/10.1145/3605389">https://doi.org/10.1145/3605389</a>.'
  ieee: 'L. Makatura <i>et al.</i>, “Procedural metamaterials: A unified procedural
    graph for metamaterial design,” <i>ACM Transactions on Graphics</i>, vol. 42,
    no. 5. Association for Computing Machinery, 2023.'
  ista: 'Makatura L, Wang B, Chen Y-L, Deng B, Wojtan C, Bickel B, Matusik W. 2023.
    Procedural metamaterials: A unified procedural graph for metamaterial design.
    ACM Transactions on Graphics. 42(5), 168.'
  mla: 'Makatura, Liane, et al. “Procedural Metamaterials: A Unified Procedural Graph
    for Metamaterial Design.” <i>ACM Transactions on Graphics</i>, vol. 42, no. 5,
    168, Association for Computing Machinery, 2023, doi:<a href="https://doi.org/10.1145/3605389">10.1145/3605389</a>.'
  short: L. Makatura, B. Wang, Y.-L. Chen, B. Deng, C. Wojtan, B. Bickel, W. Matusik,
    ACM Transactions on Graphics 42 (2023).
date_created: 2023-11-29T15:02:03Z
date_published: 2023-10-01T00:00:00Z
date_updated: 2025-09-09T13:33:58Z
day: '01'
ddc:
- '531'
- '006'
department:
- _id: GradSch
- _id: ChWo
- _id: BeBi
doi: 10.1145/3605389
external_id:
  isi:
  - '001086833300007'
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has_accepted_license: '1'
intvolume: '        42'
isi: 1
issue: '5'
keyword:
- Computer Graphics and Computer-Aided Design
language:
- iso: eng
month: '10'
oa: 1
oa_version: Published Version
project:
- _id: 34bc2376-11ca-11ed-8bc3-9a3b3961a088
  grant_number: '101045083'
  name: Computational Discovery of Numerical Algorithms for Animation and Simulation
    of Natural Phenomena
publication: ACM Transactions on Graphics
publication_identifier:
  eissn:
  - 1557-7368
  issn:
  - 0730-0301
publication_status: published
publisher: Association for Computing Machinery
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'Procedural metamaterials: A unified procedural graph for metamaterial design'
type: journal_article
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year: '2023'
...
---
_id: '14748'
acknowledged_ssus:
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acknowledgement: We thank the anonymous reviewers and the members of the Visual Computing
  Group at ISTA for their helpful comments. This research was supported by the Scientific
  Service Units (SSU) of ISTA through resources provided by Scientific Computing,
  and was funded in part by the European Union (ERC-2021-COG 101045083 CoDiNA).
article_number: '5'
article_processing_charge: No
author:
- first_name: Yi-Lu
  full_name: Chen, Yi-Lu
  id: 0b467602-dbcd-11ea-9d1d-ed480aa46b70
  last_name: Chen
- first_name: Mickaël
  full_name: Ly, Mickaël
  id: 6340d7f0-b48d-11eb-b10d-b7487e71d9f1
  last_name: Ly
- first_name: Christopher J
  full_name: Wojtan, Christopher J
  id: 3C61F1D2-F248-11E8-B48F-1D18A9856A87
  last_name: Wojtan
  orcid: 0000-0001-6646-5546
citation:
  ama: 'Chen Y-L, Ly M, Wojtan C. Unified treatment of contact, friction and shock-propagation
    in rigid body animation. In: <i>Proceedings of the ACM SIGGRAPH/Eurographics Symposium
    on Computer Animation</i>. Association for Computing Machinery; 2023. doi:<a href="https://doi.org/10.1145/3606037.3606836">10.1145/3606037.3606836</a>'
  apa: 'Chen, Y.-L., Ly, M., &#38; Wojtan, C. (2023). Unified treatment of contact,
    friction and shock-propagation in rigid body animation. In <i>Proceedings of the
    ACM SIGGRAPH/Eurographics Symposium on Computer Animation</i>. Los Angeles, CA,
    United States: Association for Computing Machinery. <a href="https://doi.org/10.1145/3606037.3606836">https://doi.org/10.1145/3606037.3606836</a>'
  chicago: Chen, Yi-Lu, Mickaël Ly, and Chris Wojtan. “Unified Treatment of Contact,
    Friction and Shock-Propagation in Rigid Body Animation.” In <i>Proceedings of
    the ACM SIGGRAPH/Eurographics Symposium on Computer Animation</i>. Association
    for Computing Machinery, 2023. <a href="https://doi.org/10.1145/3606037.3606836">https://doi.org/10.1145/3606037.3606836</a>.
  ieee: Y.-L. Chen, M. Ly, and C. Wojtan, “Unified treatment of contact, friction
    and shock-propagation in rigid body animation,” in <i>Proceedings of the ACM SIGGRAPH/Eurographics
    Symposium on Computer Animation</i>, Los Angeles, CA, United States, 2023.
  ista: 'Chen Y-L, Ly M, Wojtan C. 2023. Unified treatment of contact, friction and
    shock-propagation in rigid body animation. Proceedings of the ACM SIGGRAPH/Eurographics
    Symposium on Computer Animation. SCA: Symposium on Computer Animation, 5.'
  mla: Chen, Yi-Lu, et al. “Unified Treatment of Contact, Friction and Shock-Propagation
    in Rigid Body Animation.” <i>Proceedings of the ACM SIGGRAPH/Eurographics Symposium
    on Computer Animation</i>, 5, Association for Computing Machinery, 2023, doi:<a
    href="https://doi.org/10.1145/3606037.3606836">10.1145/3606037.3606836</a>.
  short: Y.-L. Chen, M. Ly, C. Wojtan, in:, Proceedings of the ACM SIGGRAPH/Eurographics
    Symposium on Computer Animation, Association for Computing Machinery, 2023.
conference:
  end_date: 2023-08-06
  location: Los Angeles, CA, United States
  name: 'SCA: Symposium on Computer Animation'
  start_date: 2023-08-04
corr_author: '1'
date_created: 2024-01-08T13:00:24Z
date_published: 2023-08-01T00:00:00Z
date_updated: 2025-04-14T12:58:27Z
day: '01'
department:
- _id: ChWo
doi: 10.1145/3606037.3606836
language:
- iso: eng
month: '08'
oa_version: None
project:
- _id: 34bc2376-11ca-11ed-8bc3-9a3b3961a088
  grant_number: '101045083'
  name: Computational Discovery of Numerical Algorithms for Animation and Simulation
    of Natural Phenomena
publication: Proceedings of the ACM SIGGRAPH/Eurographics Symposium on Computer Animation
publication_identifier:
  isbn:
  - '9798400702686'
publication_status: published
publisher: Association for Computing Machinery
quality_controlled: '1'
related_material:
  record:
  - id: '15292'
    relation: other
    status: public
status: public
title: Unified treatment of contact, friction and shock-propagation in rigid body
  animation
type: conference_abstract
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2023'
...
---
_id: '15292'
abstract:
- lang: eng
  text: We present a rigid body animation technique which prevents solids from interpenetrating,
    dissipates energy through friction, and propagates shocks through contacts. We
    employ the Alternating Direction Method of Multipliers (ADMM) to couple non-smooth
    Coulomb friction with impact propagation, allowing efficient and accurate non-smooth
    dynamics along with a correct transmission of impacts through assemblies of rigid
    bodies. We further extend our method to model adhesion, dynamic friction and lubricated
    contact.
acknowledgement: We thank the anonymous reviewers and the members of the Visual Computing
  Group at ISTA for their helpful comments. This research was supported by the Scientific
  Service Units (SSU) of ISTA through resources provided by Scientific Computing,
  and was funded in part by the European Union (ERC-2021-COG 101045083 CoDiNA)
article_processing_charge: No
author:
- first_name: Yi-Lu
  full_name: Chen, Yi-Lu
  id: 0b467602-dbcd-11ea-9d1d-ed480aa46b70
  last_name: Chen
- first_name: Mickaël
  full_name: Ly, Mickaël
  id: 6340d7f0-b48d-11eb-b10d-b7487e71d9f1
  last_name: Ly
- first_name: Christopher J
  full_name: Wojtan, Christopher J
  id: 3C61F1D2-F248-11E8-B48F-1D18A9856A87
  last_name: Wojtan
  orcid: 0000-0001-6646-5546
citation:
  ama: Chen Y-L, Ly M, Wojtan C. <i>Unified Treatment of Contact, Friction and Shock-Propagation
    in Rigid Body Animation</i>. ACM; 2023. doi:<a href="https://doi.org/10.1145/3606037.3606836">10.1145/3606037.3606836</a>
  apa: 'Chen, Y.-L., Ly, M., &#38; Wojtan, C. (2023). <i>Unified treatment of contact,
    friction and shock-propagation in rigid body animation</i>. <i>Proceedings of
    the ACM SIGGRAPH/Eurographics Symposium on Computer Animation</i>. Los Angeles,
    CA, United States: ACM. <a href="https://doi.org/10.1145/3606037.3606836">https://doi.org/10.1145/3606037.3606836</a>'
  chicago: Chen, Yi-Lu, Mickaël Ly, and Chris Wojtan. <i>Unified Treatment of Contact,
    Friction and Shock-Propagation in Rigid Body Animation</i>. <i>Proceedings of
    the ACM SIGGRAPH/Eurographics Symposium on Computer Animation</i>. ACM, 2023.
    <a href="https://doi.org/10.1145/3606037.3606836">https://doi.org/10.1145/3606037.3606836</a>.
  ieee: Y.-L. Chen, M. Ly, and C. Wojtan, <i>Unified treatment of contact, friction
    and shock-propagation in rigid body animation</i>. ACM, 2023.
  ista: Chen Y-L, Ly M, Wojtan C. 2023. Unified treatment of contact, friction and
    shock-propagation in rigid body animation, ACM,p.
  mla: Chen, Yi-Lu, et al. “Unified Treatment of Contact, Friction and Shock-Propagation
    in Rigid Body Animation.” <i>Proceedings of the ACM SIGGRAPH/Eurographics Symposium
    on Computer Animation</i>, ACM, 2023, doi:<a href="https://doi.org/10.1145/3606037.3606836">10.1145/3606037.3606836</a>.
  short: Y.-L. Chen, M. Ly, C. Wojtan, Unified Treatment of Contact, Friction and
    Shock-Propagation in Rigid Body Animation, ACM, 2023.
conference:
  end_date: 2023-08-06
  location: Los Angeles, CA, United States
  name: 'SCA: Symposium on Computer Animation'
  start_date: 2023-08-04
corr_author: '1'
date_created: 2024-04-03T14:57:23Z
date_published: 2023-08-01T00:00:00Z
date_updated: 2025-04-14T12:58:27Z
day: '01'
ddc:
- '005'
- '531'
department:
- _id: GradSch
- _id: ChWo
doi: 10.1145/3606037.3606836
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language:
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project:
- _id: 34bc2376-11ca-11ed-8bc3-9a3b3961a088
  grant_number: '101045083'
  name: Computational Discovery of Numerical Algorithms for Animation and Simulation
    of Natural Phenomena
publication: Proceedings of the ACM SIGGRAPH/Eurographics Symposium on Computer Animation
publication_status: published
publisher: ACM
related_material:
  record:
  - id: '14748'
    relation: other
    status: public
status: public
title: Unified treatment of contact, friction and shock-propagation in rigid body
  animation
type: conference_poster
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2023'
...
---
_id: '14240'
abstract:
- lang: eng
  text: This paper introduces a novel method for simulating large bodies of water
    as a height field. At the start of each time step, we partition the waves into
    a bulk flow (which approximately satisfies the assumptions of the shallow water
    equations) and surface waves (which approximately satisfy the assumptions of Airy
    wave theory). We then solve the two wave regimes separately using appropriate
    state-of-the-art techniques, and re-combine the resulting wave velocities at the
    end of each step. This strategy leads to the first heightfield wave model capable
    of simulating complex interactions between both deep and shallow water effects,
    like the waves from a boat wake sloshing up onto a beach, or a dam break producing
    wave interference patterns and eddies. We also analyze the numerical dispersion
    created by our method and derive an exact correction factor for waves at a constant
    water depth, giving us a numerically perfect re-creation of theoretical water
    wave dispersion patterns.
acknowledged_ssus:
- _id: ScienComp
acknowledgement: "We thank Georg Sperl for helping with early research for this paper,
  Mickael Ly and Yi-Lu Chen for proofreading, and members of the ISTA Visual Computing
  Group for general feedback. This project was funded in part by the European Research
  Council (ERC Consolidator Grant 101045083 CoDiNA).\r\nThe motorboat and sailboat
  were modeled by Sergei and the palmtrees by YadroGames. The environment map was
  created by Emil Persson."
article_number: '83'
article_processing_charge: Yes (in subscription journal)
article_type: original
author:
- first_name: Stefan
  full_name: Jeschke, Stefan
  id: 44D6411A-F248-11E8-B48F-1D18A9856A87
  last_name: Jeschke
- first_name: Christopher J
  full_name: Wojtan, Christopher J
  id: 3C61F1D2-F248-11E8-B48F-1D18A9856A87
  last_name: Wojtan
  orcid: 0000-0001-6646-5546
citation:
  ama: Jeschke S, Wojtan C. Generalizing shallow water simulations with dispersive
    surface waves. <i>ACM Transactions on Graphics</i>. 2023;42(4). doi:<a href="https://doi.org/10.1145/3592098">10.1145/3592098</a>
  apa: Jeschke, S., &#38; Wojtan, C. (2023). Generalizing shallow water simulations
    with dispersive surface waves. <i>ACM Transactions on Graphics</i>. Association
    for Computing Machinery. <a href="https://doi.org/10.1145/3592098">https://doi.org/10.1145/3592098</a>
  chicago: Jeschke, Stefan, and Chris Wojtan. “Generalizing Shallow Water Simulations
    with Dispersive Surface Waves.” <i>ACM Transactions on Graphics</i>. Association
    for Computing Machinery, 2023. <a href="https://doi.org/10.1145/3592098">https://doi.org/10.1145/3592098</a>.
  ieee: S. Jeschke and C. Wojtan, “Generalizing shallow water simulations with dispersive
    surface waves,” <i>ACM Transactions on Graphics</i>, vol. 42, no. 4. Association
    for Computing Machinery, 2023.
  ista: Jeschke S, Wojtan C. 2023. Generalizing shallow water simulations with dispersive
    surface waves. ACM Transactions on Graphics. 42(4), 83.
  mla: Jeschke, Stefan, and Chris Wojtan. “Generalizing Shallow Water Simulations
    with Dispersive Surface Waves.” <i>ACM Transactions on Graphics</i>, vol. 42,
    no. 4, 83, Association for Computing Machinery, 2023, doi:<a href="https://doi.org/10.1145/3592098">10.1145/3592098</a>.
  short: S. Jeschke, C. Wojtan, ACM Transactions on Graphics 42 (2023).
corr_author: '1'
date_created: 2023-08-27T22:01:17Z
date_published: 2023-08-01T00:00:00Z
date_updated: 2025-04-14T08:01:13Z
day: '01'
ddc:
- '000'
department:
- _id: ChWo
doi: 10.1145/3592098
external_id:
  isi:
  - '001044671300049'
file:
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  checksum: 1d178bb2f8011d9f5aedda6427e18c7a
  content_type: video/mp4
  creator: sjeschke
  date_created: 2023-12-21T12:26:40Z
  date_updated: 2023-12-21T12:26:40Z
  file_id: '14704'
  file_name: PaperVideo_final.mp4
  file_size: 511572575
  relation: main_file
  success: 1
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  checksum: a49b2e744d5cd1276bb8b2e0ce6dc638
  content_type: application/pdf
  creator: dernst
  date_created: 2024-01-02T09:34:27Z
  date_updated: 2024-01-02T09:34:27Z
  file_id: '14725'
  file_name: 2023_ACMToG_Jeschke.pdf
  file_size: 7469177
  relation: main_file
  success: 1
file_date_updated: 2024-01-02T09:34:27Z
has_accepted_license: '1'
intvolume: '        42'
isi: 1
issue: '4'
language:
- iso: eng
month: '08'
oa: 1
oa_version: Published Version
project:
- _id: 34bc2376-11ca-11ed-8bc3-9a3b3961a088
  grant_number: '101045083'
  name: Computational Discovery of Numerical Algorithms for Animation and Simulation
    of Natural Phenomena
publication: ACM Transactions on Graphics
publication_identifier:
  eissn:
  - 1557-7368
  issn:
  - 0730-0301
publication_status: published
publisher: Association for Computing Machinery
quality_controlled: '1'
scopus_import: '1'
status: public
title: Generalizing shallow water simulations with dispersive surface waves
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 42
year: '2023'
...
---
_id: '11432'
abstract:
- lang: eng
  text: "This paper proposes a method for simulating liquids in large bodies of water
    by coupling together a water surface wave simulator with a 3D Navier-Stokes simulator.
    The surface wave simulation uses the equivalent sources method (ESM) to efficiently
    animate large bodies of water with precisely controllable wave propagation behavior.
    The 3D liquid simulator animates complex non-linear fluid behaviors like splashes
    and breaking waves using off-the-shelf simulators using FLIP or the level set
    method with semi-Lagrangian advection.\r\nWe combine the two approaches by using
    the 3D solver to animate localized non-linear behaviors, and the 2D wave solver
    to animate larger regions with linear surface physics. We use the surface motion
    from the 3D solver as boundary conditions for 2D surface wave simulator, and we
    use the velocity and surface heights from the 2D surface wave simulator as boundary
    conditions for the 3D fluid simulation. We also introduce a novel technique for
    removing visual artifacts caused by numerical errors in 3D fluid solvers: we use
    experimental data to estimate the artificial dispersion caused by the 3D solver
    and we then carefully tune the wave speeds of the 2D solver to match it, effectively
    eliminating any differences in wave behavior across the boundary. To the best
    of our knowledge, this is the first time such a empirically driven error compensation
    approach has been used to remove coupling errors from a physics simulator.\r\nOur
    coupled simulation approach leverages the strengths of each simulation technique,
    animating large environments with seamless transitions between 2D and 3D physics."
acknowledged_ssus:
- _id: ScienComp
acknowledgement: We wish to thank the anonymous reviewers and the members of the Visual
  Computing Group at IST Austria and MFX Team at INRIA for their valuable feedback.
  This research was supported by the Scientific Service Units (SSU) of IST Austria
  through resources provided by Scientific Computing. This project has received funding
  from the European Research Council (ERC) under the European Union’s Horizon 2020
  research and innovation programme under grant agreement No. 638176.
article_processing_charge: No
article_type: original
author:
- first_name: Camille
  full_name: Schreck, Camille
  id: 2B14B676-F248-11E8-B48F-1D18A9856A87
  last_name: Schreck
- first_name: Christopher J
  full_name: Wojtan, Christopher J
  id: 3C61F1D2-F248-11E8-B48F-1D18A9856A87
  last_name: Wojtan
  orcid: 0000-0001-6646-5546
citation:
  ama: Schreck C, Wojtan C. Coupling 3D liquid simulation with 2D wave propagation
    for large scale water surface animation using the equivalent sources method. <i>Computer
    Graphics Forum</i>. 2022;41(2):343-353. doi:<a href="https://doi.org/10.1111/cgf.14478">10.1111/cgf.14478</a>
  apa: Schreck, C., &#38; Wojtan, C. (2022). Coupling 3D liquid simulation with 2D
    wave propagation for large scale water surface animation using the equivalent
    sources method. <i>Computer Graphics Forum</i>. Wiley. <a href="https://doi.org/10.1111/cgf.14478">https://doi.org/10.1111/cgf.14478</a>
  chicago: Schreck, Camille, and Chris Wojtan. “Coupling 3D Liquid Simulation with
    2D Wave Propagation for Large Scale Water Surface Animation Using the Equivalent
    Sources Method.” <i>Computer Graphics Forum</i>. Wiley, 2022. <a href="https://doi.org/10.1111/cgf.14478">https://doi.org/10.1111/cgf.14478</a>.
  ieee: C. Schreck and C. Wojtan, “Coupling 3D liquid simulation with 2D wave propagation
    for large scale water surface animation using the equivalent sources method,”
    <i>Computer Graphics Forum</i>, vol. 41, no. 2. Wiley, pp. 343–353, 2022.
  ista: Schreck C, Wojtan C. 2022. Coupling 3D liquid simulation with 2D wave propagation
    for large scale water surface animation using the equivalent sources method. Computer
    Graphics Forum. 41(2), 343–353.
  mla: Schreck, Camille, and Chris Wojtan. “Coupling 3D Liquid Simulation with 2D
    Wave Propagation for Large Scale Water Surface Animation Using the Equivalent
    Sources Method.” <i>Computer Graphics Forum</i>, vol. 41, no. 2, Wiley, 2022,
    pp. 343–53, doi:<a href="https://doi.org/10.1111/cgf.14478">10.1111/cgf.14478</a>.
  short: C. Schreck, C. Wojtan, Computer Graphics Forum 41 (2022) 343–353.
corr_author: '1'
date_created: 2022-06-05T22:01:49Z
date_published: 2022-05-01T00:00:00Z
date_updated: 2024-10-22T09:58:19Z
day: '01'
department:
- _id: ChWo
doi: 10.1111/cgf.14478
ec_funded: 1
external_id:
  isi:
  - '000802723900027'
intvolume: '        41'
isi: 1
issue: '2'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://hal.archives-ouvertes.fr/hal-03641349/
month: '05'
oa: 1
oa_version: Submitted Version
page: 343-353
project:
- _id: 2533E772-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '638176'
  name: 'Big Splash: Efficient Simulation of Natural Phenomena at Extremely Large
    Scales'
publication: Computer Graphics Forum
publication_identifier:
  eissn:
  - 1467-8659
  issn:
  - 0167-7055
publication_status: published
publisher: Wiley
quality_controlled: '1'
scopus_import: '1'
status: public
title: Coupling 3D liquid simulation with 2D wave propagation for large scale water
  surface animation using the equivalent sources method
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 41
year: '2022'
...
