[{"_id":"14628","publication_identifier":{"issn":["0730-0301","1557-7368"]},"article_number":"168","ddc":["531","006"],"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_processing_charge":"Yes (in subscription journal)","quality_controlled":"1","volume":42,"has_accepted_license":"1","type":"journal_article","author":[{"first_name":"Liane","last_name":"Makatura","full_name":"Makatura, Liane"},{"first_name":"Bohan","last_name":"Wang","full_name":"Wang, Bohan"},{"first_name":"Yi-Lu","id":"0b467602-dbcd-11ea-9d1d-ed480aa46b70","full_name":"Chen, Yi-Lu","last_name":"Chen"},{"first_name":"Bolei","last_name":"Deng","full_name":"Deng, Bolei"},{"last_name":"Wojtan","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J","first_name":"Christopher J","orcid":"0000-0001-6646-5546"},{"last_name":"Bickel","full_name":"Bickel, Bernd","id":"49876194-F248-11E8-B48F-1D18A9856A87","first_name":"Bernd","orcid":"0000-0001-6511-9385"},{"full_name":"Matusik, Wojciech","last_name":"Matusik","first_name":"Wojciech"}],"publisher":"Association for Computing Machinery","month":"10","language":[{"iso":"eng"}],"date_published":"2023-10-01T00:00:00Z","date_updated":"2023-12-04T08:09:05Z","day":"01","oa_version":"Published Version","citation":{"ama":"Makatura L, Wang B, Chen Y-L, et al. Procedural metamaterials: A unified procedural graph for metamaterial design. ACM Transactions on Graphics. 2023;42(5). doi:10.1145/3605389","short":"L. Makatura, B. Wang, Y.-L. Chen, B. Deng, C. Wojtan, B. Bickel, W. Matusik, ACM Transactions on Graphics 42 (2023).","mla":"Makatura, Liane, et al. “Procedural Metamaterials: A Unified Procedural Graph for Metamaterial Design.” ACM Transactions on Graphics, vol. 42, no. 5, 168, Association for Computing Machinery, 2023, doi:10.1145/3605389.","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.","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.” ACM Transactions on Graphics. Association for Computing Machinery, 2023. https://doi.org/10.1145/3605389.","apa":"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. Association for Computing Machinery. https://doi.org/10.1145/3605389","ieee":"L. Makatura et al., “Procedural metamaterials: A unified procedural graph for metamaterial design,” ACM Transactions on Graphics, vol. 42, no. 5. Association for Computing Machinery, 2023."},"title":"Procedural metamaterials: A unified procedural graph for metamaterial design","date_created":"2023-11-29T15:02:03Z","doi":"10.1145/3605389","file_date_updated":"2023-12-04T08:04:14Z","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","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."}],"file":[{"date_updated":"2023-11-29T15:16:01Z","success":1,"content_type":"application/zip","file_id":"14630","checksum":"0192f597d7a2ceaf89baddfd6190d4c8","date_created":"2023-11-29T15:16:01Z","file_size":95467870,"relation":"main_file","file_name":"tog-22-0089-File004.zip","access_level":"open_access","creator":"yichen"},{"date_updated":"2023-11-29T15:16:01Z","success":1,"content_type":"application/zip","checksum":"7fb024963be81933494f38de191e4710","file_id":"14631","access_level":"open_access","file_name":"tog-22-0089-File005.zip","creator":"yichen","file_size":103731880,"date_created":"2023-11-29T15:16:01Z","relation":"main_file"},{"content_type":"application/pdf","date_updated":"2023-12-04T08:04:14Z","success":1,"access_level":"open_access","file_name":"2023_ACMToG_Makatura.pdf","creator":"dernst","file_size":57067476,"date_created":"2023-12-04T08:04:14Z","relation":"main_file","checksum":"b7d6829ce396e21cac9fae0ec7130a6b","file_id":"14638"}],"project":[{"name":"Computational Discovery of Numerical Algorithms for Animation and Simulation of Natural Phenomena","grant_number":"101045083","_id":"34bc2376-11ca-11ed-8bc3-9a3b3961a088"}],"oa":1,"article_type":"original","intvolume":" 42","publication":"ACM Transactions on Graphics","issue":"5","year":"2023","keyword":["Computer Graphics and Computer-Aided Design"],"department":[{"_id":"GradSch"},{"_id":"ChWo"},{"_id":"BeBi"}],"status":"public","publication_status":"published"},{"issue":"4","publication":"ACM Transactions on Graphics","intvolume":" 42","publication_status":"published","department":[{"_id":"ChWo"}],"status":"public","year":"2023","date_created":"2023-08-27T22:01:17Z","title":"Generalizing shallow water simulations with dispersive surface waves","citation":{"ama":"Jeschke S, Wojtan C. Generalizing shallow water simulations with dispersive surface waves. ACM Transactions on Graphics. 2023;42(4). doi:10.1145/3592098","short":"S. Jeschke, C. Wojtan, ACM Transactions on Graphics 42 (2023).","mla":"Jeschke, Stefan, and Chris Wojtan. “Generalizing Shallow Water Simulations with Dispersive Surface Waves.” ACM Transactions on Graphics, vol. 42, no. 4, 83, Association for Computing Machinery, 2023, doi:10.1145/3592098.","chicago":"Jeschke, Stefan, and Chris Wojtan. “Generalizing Shallow Water Simulations with Dispersive Surface Waves.” ACM Transactions on Graphics. Association for Computing Machinery, 2023. https://doi.org/10.1145/3592098.","ista":"Jeschke S, Wojtan C. 2023. Generalizing shallow water simulations with dispersive surface waves. ACM Transactions on Graphics. 42(4), 83.","ieee":"S. Jeschke and C. Wojtan, “Generalizing shallow water simulations with dispersive surface waves,” ACM Transactions on Graphics, vol. 42, no. 4. Association for Computing Machinery, 2023.","apa":"Jeschke, S., & Wojtan, C. (2023). Generalizing shallow water simulations with dispersive surface waves. ACM Transactions on Graphics. Association for Computing Machinery. https://doi.org/10.1145/3592098"},"oa_version":"Published Version","tmp":{"name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","short":"CC BY (4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","image":"/images/cc_by.png"},"oa":1,"article_type":"original","file":[{"file_name":"PaperVideo_final.mp4","access_level":"open_access","creator":"sjeschke","date_created":"2023-12-21T12:26:40Z","file_size":511572575,"relation":"main_file","checksum":"1d178bb2f8011d9f5aedda6427e18c7a","file_id":"14704","content_type":"video/mp4","date_updated":"2023-12-21T12:26:40Z","success":1},{"file_id":"14725","checksum":"a49b2e744d5cd1276bb8b2e0ce6dc638","date_created":"2024-01-02T09:34:27Z","file_size":7469177,"relation":"main_file","access_level":"open_access","file_name":"2023_ACMToG_Jeschke.pdf","creator":"dernst","date_updated":"2024-01-02T09:34:27Z","success":1,"content_type":"application/pdf"}],"project":[{"grant_number":"101045083","name":"Computational Discovery of Numerical Algorithms for Animation and Simulation of Natural Phenomena","_id":"34bc2376-11ca-11ed-8bc3-9a3b3961a088"}],"doi":"10.1145/3592098","file_date_updated":"2024-01-02T09:34:27Z","acknowledged_ssus":[{"_id":"ScienComp"}],"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."}],"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","external_id":{"isi":["001044671300049"]},"date_published":"2023-08-01T00:00:00Z","language":[{"iso":"eng"}],"month":"08","isi":1,"day":"01","date_updated":"2024-01-02T09:35:55Z","quality_controlled":"1","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_processing_charge":"Yes (in subscription journal)","ddc":["000"],"article_number":"83","_id":"14240","publication_identifier":{"eissn":["1557-7368"],"issn":["0730-0301"]},"author":[{"first_name":"Stefan","last_name":"Jeschke","full_name":"Jeschke, Stefan","id":"44D6411A-F248-11E8-B48F-1D18A9856A87"},{"full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","last_name":"Wojtan","orcid":"0000-0001-6646-5546","first_name":"Christopher J"}],"publisher":"Association for Computing Machinery","scopus_import":"1","type":"journal_article","volume":42,"has_accepted_license":"1"},{"date_published":"2023-08-01T00:00:00Z","language":[{"iso":"eng"}],"conference":{"location":"Los Angeles, CA, United States","start_date":"2023-08-04","end_date":"2023-08-06","name":"SCA: Symposium on Computer Animation"},"month":"08","publication":"Proceedings of the ACM SIGGRAPH/Eurographics Symposium on Computer Animation","day":"01","publication_status":"published","status":"public","department":[{"_id":"ChWo"}],"date_updated":"2024-02-28T12:51:40Z","year":"2023","title":"Unified treatment of contact, friction and shock-propagation in rigid body animation","date_created":"2024-01-08T13:00:24Z","quality_controlled":"1","citation":{"ieee":"Y.-L. Chen, M. Ly, and C. Wojtan, “Unified treatment of contact, friction and shock-propagation in rigid body animation,” in Proceedings of the ACM SIGGRAPH/Eurographics Symposium on Computer Animation, Los Angeles, CA, United States, 2023.","apa":"Chen, Y.-L., Ly, M., & Wojtan, C. (2023). Unified treatment of contact, friction and shock-propagation in rigid body animation. In Proceedings of the ACM SIGGRAPH/Eurographics Symposium on Computer Animation. Los Angeles, CA, United States: Association for Computing Machinery. https://doi.org/10.1145/3606037.3606836","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.","chicago":"Chen, Yi-Lu, Mickaël Ly, and Chris Wojtan. “Unified Treatment of Contact, Friction and Shock-Propagation in Rigid Body Animation.” In Proceedings of the ACM SIGGRAPH/Eurographics Symposium on Computer Animation. Association for Computing Machinery, 2023. https://doi.org/10.1145/3606037.3606836.","short":"Y.-L. Chen, M. Ly, C. Wojtan, in:, Proceedings of the ACM SIGGRAPH/Eurographics Symposium on Computer Animation, Association for Computing Machinery, 2023.","mla":"Chen, Yi-Lu, et al. “Unified Treatment of Contact, Friction and Shock-Propagation in Rigid Body Animation.” Proceedings of the ACM SIGGRAPH/Eurographics Symposium on Computer Animation, 5, Association for Computing Machinery, 2023, doi:10.1145/3606037.3606836.","ama":"Chen Y-L, Ly M, Wojtan C. Unified treatment of contact, friction and shock-propagation in rigid body animation. In: Proceedings of the ACM SIGGRAPH/Eurographics Symposium on Computer Animation. Association for Computing Machinery; 2023. doi:10.1145/3606037.3606836"},"article_processing_charge":"No","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).","oa_version":"None","article_number":"5","_id":"14748","publication_identifier":{"isbn":["9798400702686"]},"author":[{"first_name":"Yi-Lu","last_name":"Chen","full_name":"Chen, Yi-Lu","id":"0b467602-dbcd-11ea-9d1d-ed480aa46b70"},{"first_name":"Mickaël","id":"6340d7f0-b48d-11eb-b10d-b7487e71d9f1","full_name":"Ly, Mickaël","last_name":"Ly"},{"last_name":"Wojtan","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","first_name":"Christopher J","orcid":"0000-0001-6646-5546"}],"publisher":"Association for Computing Machinery","project":[{"grant_number":"101045083","name":"Computational Discovery of Numerical Algorithms for Animation and Simulation of Natural Phenomena","_id":"34bc2376-11ca-11ed-8bc3-9a3b3961a088"}],"type":"conference_abstract","acknowledged_ssus":[{"_id":"ScienComp"}],"doi":"10.1145/3606037.3606836","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87"},{"volume":41,"scopus_import":"1","type":"journal_article","publisher":"Wiley","author":[{"last_name":"Schreck","full_name":"Schreck, Camille","id":"2B14B676-F248-11E8-B48F-1D18A9856A87","first_name":"Camille"},{"last_name":"Wojtan","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","first_name":"Christopher J","orcid":"0000-0001-6646-5546"}],"publication_identifier":{"issn":["0167-7055"],"eissn":["1467-8659"]},"_id":"11432","article_processing_charge":"No","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.","quality_controlled":"1","date_updated":"2023-08-02T06:44:05Z","day":"01","isi":1,"month":"05","language":[{"iso":"eng"}],"date_published":"2022-05-01T00:00:00Z","external_id":{"isi":["000802723900027"]},"abstract":[{"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.","lang":"eng"}],"user_id":"4359f0d1-fa6c-11eb-b949-802e58b17ae8","acknowledged_ssus":[{"_id":"ScienComp"}],"doi":"10.1111/cgf.14478","project":[{"call_identifier":"H2020","grant_number":"638176","name":"Efficient Simulation of Natural Phenomena at Extremely Large Scales","_id":"2533E772-B435-11E9-9278-68D0E5697425"}],"oa":1,"article_type":"original","page":"343-353","ec_funded":1,"main_file_link":[{"url":"https://hal.archives-ouvertes.fr/hal-03641349/","open_access":"1"}],"oa_version":"Submitted Version","citation":{"short":"C. Schreck, C. Wojtan, Computer Graphics Forum 41 (2022) 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.” Computer Graphics Forum, vol. 41, no. 2, Wiley, 2022, pp. 343–53, doi:10.1111/cgf.14478.","ama":"Schreck C, Wojtan C. Coupling 3D liquid simulation with 2D wave propagation for large scale water surface animation using the equivalent sources method. Computer Graphics Forum. 2022;41(2):343-353. doi:10.1111/cgf.14478","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,” Computer Graphics Forum, vol. 41, no. 2. Wiley, pp. 343–353, 2022.","apa":"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. Wiley. https://doi.org/10.1111/cgf.14478","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.” Computer Graphics Forum. Wiley, 2022. https://doi.org/10.1111/cgf.14478.","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."},"title":"Coupling 3D liquid simulation with 2D wave propagation for large scale water surface animation using the equivalent sources method","date_created":"2022-06-05T22:01:49Z","year":"2022","status":"public","department":[{"_id":"ChWo"}],"publication_status":"published","intvolume":" 41","publication":"Computer Graphics Forum","issue":"2"},{"intvolume":" 41","publication":"ACM Transactions on Graphics","issue":"4","year":"2022","status":"public","department":[{"_id":"ChWo"}],"publication_status":"published","main_file_link":[{"url":"https://doi.org/10.1145/3528223.3530167","open_access":"1"}],"related_material":{"record":[{"relation":"dissertation_contains","status":"public","id":"12358"}],"link":[{"url":"https://ista.ac.at/en/news/digital-yarn-real-socks/","description":"News on the ISTA website","relation":"press_release"}]},"oa_version":"Published Version","citation":{"ieee":"G. Sperl, R. M. Sánchez-Banderas, M. Li, C. Wojtan, and M. A. Otaduy, “Estimation of yarn-level simulation models for production fabrics,” ACM Transactions on Graphics, vol. 41, no. 4. Association for Computing Machinery, 2022.","apa":"Sperl, G., Sánchez-Banderas, R. M., Li, M., Wojtan, C., & Otaduy, M. A. (2022). Estimation of yarn-level simulation models for production fabrics. ACM Transactions on Graphics. Association for Computing Machinery. https://doi.org/10.1145/3528223.3530167","chicago":"Sperl, Georg, Rosa M. Sánchez-Banderas, Manwen Li, Chris Wojtan, and Miguel A. Otaduy. “Estimation of Yarn-Level Simulation Models for Production Fabrics.” ACM Transactions on Graphics. Association for Computing Machinery, 2022. https://doi.org/10.1145/3528223.3530167.","ista":"Sperl G, Sánchez-Banderas RM, Li M, Wojtan C, Otaduy MA. 2022. Estimation of yarn-level simulation models for production fabrics. ACM Transactions on Graphics. 41(4), 65.","mla":"Sperl, Georg, et al. “Estimation of Yarn-Level Simulation Models for Production Fabrics.” ACM Transactions on Graphics, vol. 41, no. 4, 65, Association for Computing Machinery, 2022, doi:10.1145/3528223.3530167.","short":"G. Sperl, R.M. Sánchez-Banderas, M. Li, C. Wojtan, M.A. Otaduy, ACM Transactions on Graphics 41 (2022).","ama":"Sperl G, Sánchez-Banderas RM, Li M, Wojtan C, Otaduy MA. Estimation of yarn-level simulation models for production fabrics. ACM Transactions on Graphics. 2022;41(4). doi:10.1145/3528223.3530167"},"date_created":"2022-08-07T22:01:58Z","title":"Estimation of yarn-level simulation models for production fabrics","doi":"10.1145/3528223.3530167","acknowledged_ssus":[{"_id":"ScienComp"}],"abstract":[{"text":"This paper introduces a methodology for inverse-modeling of yarn-level mechanics of cloth, based on the mechanical response of fabrics in the real world. We compiled a database from physical tests of several different knitted fabrics used in the textile industry. These data span different types of complex knit patterns, yarn compositions, and fabric finishes, and the results demonstrate diverse physical properties like stiffness, nonlinearity, and anisotropy.\r\n\r\nWe then develop a system for approximating these mechanical responses with yarn-level cloth simulation. To do so, we introduce an efficient pipeline for converting between fabric-level data and yarn-level simulation, including a novel swatch-level approximation for speeding up computation, and some small-but-necessary extensions to yarn-level models used in computer graphics. The dataset used for this paper can be found at http://mslab.es/projects/YarnLevelFabrics.","lang":"eng"}],"user_id":"4359f0d1-fa6c-11eb-b949-802e58b17ae8","oa":1,"article_type":"original","isi":1,"month":"07","language":[{"iso":"eng"}],"external_id":{"isi":["000830989200114"]},"date_published":"2022-07-22T00:00:00Z","date_updated":"2023-08-03T12:38:30Z","day":"22","_id":"11736","publication_identifier":{"issn":["0730-0301"],"eissn":["1557-7368"]},"article_number":"65","article_processing_charge":"No","acknowledgement":"We wish to thank the anonymous reviewers for their helpful comments. To develop this project, we were helped by many people both at Under Armour (Clay Dean, Randall Harward, Kyle Blakely, Craig Simile, Michael Seiz, Brooke Malone, Brittainy McFarland, Emilie Phan, Lindsey Kern, Courtney Oswald, Haley Barkley, Bob Chin, Adam Bayer, Connie Kwok, Marielle Newman, Nick Pence, Allison Hicks, Allison White, Candace Rubenstein, Jeremy Stangland, Fred Fagergren, Michael Mazzoleni, Nathaniel Berry, Manuel Frank) and SEDDI (Gabriel Cirio, Alejandro Rodríguez, Sofía Dominguez, Alicia Nicas, Elena Garcés, Daniel Rodríguez, David Pascual, Manuel Godoy, Sergio Suja, Sergio Ruiz, Roberto Condori, Alberto Martín, Graham Sullivan). We also thank the members of the Visual Computing Group at IST Austria and the Multimodal Simulation Lab at URJC for their feedback. This research was supported by the Scientific Service Units (SSU) of IST Austria through resources provided by Scientific Computing, and it was funded in part by the European Research Council (ERC Consolidator Grant 772738 TouchDesign).","quality_controlled":"1","volume":41,"type":"journal_article","scopus_import":"1","author":[{"first_name":"Georg","last_name":"Sperl","id":"4DD40360-F248-11E8-B48F-1D18A9856A87","full_name":"Sperl, Georg"},{"last_name":"Sánchez-Banderas","full_name":"Sánchez-Banderas, Rosa M.","first_name":"Rosa M."},{"first_name":"Manwen","full_name":"Li, Manwen","last_name":"Li"},{"first_name":"Christopher J","orcid":"0000-0001-6646-5546","last_name":"Wojtan","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87"},{"full_name":"Otaduy, Miguel A.","last_name":"Otaduy","first_name":"Miguel A."}],"publisher":"Association for Computing Machinery"},{"quality_controlled":"1","acknowledgement":"We thank the visual computing group at IST Austria for their valuable discussions and feedback. Houdini Education licenses were provided by SideFX software. This project was funded in part by the European Research Council (ERC Consolidator Grant 101045083 CoDiNA).","article_processing_charge":"No","ddc":["000"],"article_number":"241","_id":"12431","publication_identifier":{"eissn":["1557-7368"],"issn":["0730-0301"]},"author":[{"first_name":"Sadashige","last_name":"Ishida","full_name":"Ishida, Sadashige","id":"6F7C4B96-A8E9-11E9-A7CA-09ECE5697425"},{"last_name":"Wojtan","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","first_name":"Christopher J","orcid":"0000-0001-6646-5546"},{"first_name":"Albert","full_name":"Chern, Albert","last_name":"Chern"}],"publisher":"Association for Computing Machinery","type":"journal_article","scopus_import":"1","volume":41,"has_accepted_license":"1","external_id":{"isi":["000891651900061"]},"date_published":"2022-12-01T00:00:00Z","language":[{"iso":"eng"}],"month":"12","isi":1,"day":"01","date_updated":"2023-08-04T09:37:23Z","date_created":"2023-01-29T23:00:59Z","title":"Hidden degrees of freedom in implicit vortex filaments","citation":{"ama":"Ishida S, Wojtan C, Chern A. 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Instead of representing these filaments with explicit curve geometry and Lagrangian equations of motion, we represent curves implicitly with a new co-dimensional 2 level set description. Our implicit representation admits several redundant mathematical degrees of freedom in both the configuration and the dynamics of the curves, which can be tailored specifically to improve numerical robustness, in contrast to naive approaches for implicit curve dynamics that suffer from overwhelming numerical stability problems. Furthermore, we note how these hidden degrees of freedom perfectly map to a Clebsch representation in fluid dynamics. Motivated by these observations, we introduce untwisted level set functions and non-swirling dynamics which successfully regularize sources of numerical instability, particularly in the twisting modes around curve filaments. A consequence is a novel simulation method which produces stable dynamics for large numbers of interacting vortex filaments and effortlessly handles topological changes and re-connection events.","lang":"eng"}],"issue":"6","publication":"ACM Transactions on Graphics","intvolume":" 41","publication_status":"published","status":"public","department":[{"_id":"ChWo"}],"year":"2022"},{"project":[{"_id":"2533E772-B435-11E9-9278-68D0E5697425","call_identifier":"H2020","name":"Efficient Simulation of Natural Phenomena at Extremely Large Scales","grant_number":"638176"}],"user_id":"4359f0d1-fa6c-11eb-b949-802e58b17ae8","abstract":[{"text":"Triangle mesh-based simulations are able to produce satisfying animations of knitted and woven cloth; however, they lack the rich geometric detail of yarn-level simulations. Naive texturing approaches do not consider yarn-level physics, while full yarn-level simulations may become prohibitively expensive for large garments. We propose a method to animate yarn-level cloth geometry on top of an underlying deforming mesh in a mechanics-aware fashion. Using triangle strains to interpolate precomputed yarn geometry, we are able to reproduce effects such as knit loops tightening under stretching. 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We also thank Seddi Labs for providing the garment model with fold-over seams.\r\nThis research was supported by the Scientific Service Units (SSU) of IST Austria through resources provided by Scientific\r\nComputing. 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. Rahul Narain is supported by a Pankaj Gupta Young Faculty Fellowship and a gift from Adobe Inc.","date_updated":"2023-08-10T14:24:36Z","day":"01","month":"08","isi":1,"date_published":"2021-08-01T00:00:00Z","external_id":{"isi":["000674930900132"]},"language":[{"iso":"eng"}]},{"license":"https://opensource.org/licenses/MIT","department":[{"_id":"GradSch"},{"_id":"ChWo"}],"status":"public","date_updated":"2023-08-10T14:24:36Z","year":"2021","date_published":"2021-05-01T00:00:00Z","gitlab_url":"https://git.ist.ac.at/gsperl/MADYPG","month":"05","oa":1,"author":[{"first_name":"Georg","last_name":"Sperl","id":"4DD40360-F248-11E8-B48F-1D18A9856A87","full_name":"Sperl, Georg"},{"first_name":"Rahul","full_name":"Narain, Rahul","last_name":"Narain"},{"orcid":"0000-0001-6646-5546","first_name":"Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J","last_name":"Wojtan"}],"publisher":"IST Austria","gitlab_commit_id":"6a77e7e22769230ae5f5edaa090fb4b828e57573","file":[{"file_id":"9328","checksum":"0324cb519273371708743f3282e7c081","relation":"main_file","date_created":"2021-04-16T14:15:12Z","file_size":802586232,"creator":"gsperl","access_level":"open_access","file_name":"MADYPG_extra_data.zip","success":1,"date_updated":"2021-04-16T14:15:12Z","content_type":"application/zip"},{"checksum":"4c224551adf852b136ec21a4e13f0c1b","file_id":"9353","creator":"pub-gitlab-bot","file_name":"MADYPG.zip","access_level":"open_access","relation":"main_file","date_created":"2021-04-26T09:33:44Z","file_size":64962865,"date_updated":"2021-04-26T09:33:44Z","content_type":"application/gzip"}],"type":"software","file_date_updated":"2021-04-26T09:33:44Z","doi":"10.15479/AT:ISTA:9327","abstract":[{"text":"This archive contains the missing sweater mesh animations and displacement models for the code of \"Mechanics-Aware Deformation of Yarn Pattern Geometry\"\r\n\r\nCode Repository: https://git.ist.ac.at/gsperl/MADYPG","lang":"eng"}],"has_accepted_license":"1","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","title":"Mechanics-Aware Deformation of Yarn Pattern Geometry (Additional Animation/Model Data)","date_created":"2021-04-16T14:26:19Z","citation":{"mla":"Sperl, Georg, et al. 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Our method works as a post-processing step which takes a simulation as input and increases its apparent resolution by simulating many detailed Lagrangian water waves on top of it. We extend linear water wave theory to work in non-planar domains which deform over time, and we discretize the theory using Lagrangian wave packets attached to spline curves. The method is numerically stable and trivially parallelizable, and it produces high frequency ripples with dispersive wave-like behaviors customized to the underlying fluid simulation."}],"user_id":"4359f0d1-fa6c-11eb-b949-802e58b17ae8","file":[{"content_type":"application/pdf","success":1,"date_updated":"2020-09-21T07:51:44Z","creator":"dernst","access_level":"open_access","file_name":"2020_ACM_Skrivan.pdf","relation":"main_file","file_size":20223953,"date_created":"2020-09-21T07:51:44Z","checksum":"c3a680893f01cc4a9e961ff0a4cfa12f","file_id":"8541"}],"project":[{"call_identifier":"H2020","grant_number":"638176","name":"Efficient Simulation of Natural Phenomena at Extremely Large Scales","_id":"2533E772-B435-11E9-9278-68D0E5697425"},{"_id":"2564DBCA-B435-11E9-9278-68D0E5697425","call_identifier":"H2020","grant_number":"665385","name":"International IST Doctoral Program"}],"oa":1,"article_type":"original","isi":1,"month":"07","language":[{"iso":"eng"}],"external_id":{"isi":["000583700300038"]},"date_published":"2020-07-08T00:00:00Z","date_updated":"2023-08-22T09:28:27Z","day":"08","_id":"8535","publication_identifier":{"eissn":["15577368"],"issn":["07300301"]},"article_number":"65","ddc":["000"],"article_processing_charge":"No","acknowledgement":"We wish to thank the anonymous reviewers and the members of the Visual Computing Group at IST Austria 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 and Marie SkłodowskaCurie Grant Agreement No. 665385.","quality_controlled":"1","volume":39,"has_accepted_license":"1","scopus_import":"1","type":"journal_article","author":[{"full_name":"Skrivan, Tomas","id":"486A5A46-F248-11E8-B48F-1D18A9856A87","last_name":"Skrivan","first_name":"Tomas"},{"last_name":"Soderstrom","full_name":"Soderstrom, Andreas","first_name":"Andreas"},{"full_name":"Johansson, John","last_name":"Johansson","first_name":"John"},{"last_name":"Sprenger","full_name":"Sprenger, Christoph","first_name":"Christoph"},{"first_name":"Ken","last_name":"Museth","full_name":"Museth, Ken"},{"id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J","last_name":"Wojtan","orcid":"0000-0001-6646-5546","first_name":"Christopher J"}],"publisher":"Association for Computing Machinery"},{"oa":1,"article_type":"original","page":"89-99","abstract":[{"text":"This paper introduces a simple method for simulating highly anisotropic elastoplastic material behaviors like the dissolution of fibrous phenomena (splintering wood, shredding bales of hay) and materials composed of large numbers of irregularly‐shaped bodies (piles of twigs, pencils, or cards). We introduce a simple transformation of the anisotropic problem into an equivalent isotropic one, and we solve this new “fictitious” isotropic problem using an existing simulator based on the material point method. Our approach results in minimal changes to existing simulators, and it allows us to re‐use popular isotropic plasticity models like the Drucker‐Prager yield criterion instead of inventing new anisotropic plasticity models for every phenomenon we wish to simulate.","lang":"eng"}],"user_id":"c635000d-4b10-11ee-a964-aac5a93f6ac1","file_date_updated":"2020-11-23T09:05:13Z","doi":"10.1111/cgf.13914","acknowledged_ssus":[{"_id":"ScienComp"}],"project":[{"_id":"2533E772-B435-11E9-9278-68D0E5697425","call_identifier":"H2020","name":"Efficient Simulation of Natural Phenomena at Extremely Large Scales","grant_number":"638176"}],"file":[{"date_updated":"2020-11-23T09:05:13Z","success":1,"content_type":"application/pdf","file_id":"8796","checksum":"7605f605acd84d0942b48bc7a1c2d72e","date_created":"2020-11-23T09:05:13Z","file_size":38969122,"relation":"main_file","access_level":"open_access","file_name":"2020_poff_revisited.pdf","creator":"dernst"}],"citation":{"mla":"Schreck, Camille, and Chris Wojtan. “A Practical Method for Animating Anisotropic Elastoplastic Materials.” Computer Graphics Forum, vol. 39, no. 2, Wiley, 2020, pp. 89–99, doi:10.1111/cgf.13914.","short":"C. Schreck, C. Wojtan, Computer Graphics Forum 39 (2020) 89–99.","ama":"Schreck C, Wojtan C. A practical method for animating anisotropic elastoplastic materials. Computer Graphics Forum. 2020;39(2):89-99. doi:10.1111/cgf.13914","apa":"Schreck, C., & Wojtan, C. (2020). A practical method for animating anisotropic elastoplastic materials. Computer Graphics Forum. Wiley. https://doi.org/10.1111/cgf.13914","ieee":"C. Schreck and C. Wojtan, “A practical method for animating anisotropic elastoplastic materials,” Computer Graphics Forum, vol. 39, no. 2. Wiley, pp. 89–99, 2020.","ista":"Schreck C, Wojtan C. 2020. A practical method for animating anisotropic elastoplastic materials. Computer Graphics Forum. 39(2), 89–99.","chicago":"Schreck, Camille, and Chris Wojtan. “A Practical Method for Animating Anisotropic Elastoplastic Materials.” Computer Graphics Forum. Wiley, 2020. https://doi.org/10.1111/cgf.13914."},"title":"A practical method for animating anisotropic elastoplastic materials","date_created":"2020-11-17T09:35:10Z","ec_funded":1,"oa_version":"Submitted Version","department":[{"_id":"ChWo"}],"status":"public","keyword":["Computer Networks and Communications"],"publication_status":"published","year":"2020","issue":"2","intvolume":" 39","publication":"Computer Graphics Forum","publisher":"Wiley","author":[{"id":"2B14B676-F248-11E8-B48F-1D18A9856A87","full_name":"Schreck, Camille","last_name":"Schreck","first_name":"Camille"},{"full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","last_name":"Wojtan","orcid":"0000-0001-6646-5546","first_name":"Christopher J"}],"has_accepted_license":"1","volume":39,"scopus_import":"1","type":"journal_article","acknowledgement":"We wish to thank the anonymous reviewers and the members of the Visual Computing Group at IST Austria for their valuable feedback. This research was supported by the Scientific Service Units (SSU) of IST Austria through resources provided by Scientific Computing. We would also like to thank Joseph Teran and Chenfanfu Jiang for the helpful discussions.\r\nThis 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","quality_controlled":"1","publication_identifier":{"eissn":["1467-8659"],"issn":["0167-7055"]},"_id":"8765","ddc":["000"],"day":"01","date_updated":"2023-09-05T16:00:13Z","language":[{"iso":"eng"}],"date_published":"2020-05-01T00:00:00Z","external_id":{"isi":["000548709600008"]},"isi":1,"month":"05"},{"publication":"IEEE Transactions on Visualization and Computer Graphics","intvolume":" 26","issue":"6","year":"2020","publication_status":"published","status":"public","department":[{"_id":"ChWo"}],"oa_version":"Submitted Version","title":"Simulating liquids on dynamically warping grids","date_created":"2018-12-16T22:59:21Z","citation":{"ieee":"I. Hikaru, C. Wojtan, N. Thuerey, T. Igarashi, and R. Ando, “Simulating liquids on dynamically warping grids,” IEEE Transactions on Visualization and Computer Graphics, vol. 26, no. 6. IEEE, pp. 2288–2302, 2020.","apa":"Hikaru, I., Wojtan, C., Thuerey, N., Igarashi, T., & Ando, R. (2020). Simulating liquids on dynamically warping grids. IEEE Transactions on Visualization and Computer Graphics. IEEE. https://doi.org/10.1109/TVCG.2018.2883628","chicago":"Hikaru, Ibayashi, Chris Wojtan, Nils Thuerey, Takeo Igarashi, and Ryoichi Ando. “Simulating Liquids on Dynamically Warping Grids.” IEEE Transactions on Visualization and Computer Graphics. IEEE, 2020. https://doi.org/10.1109/TVCG.2018.2883628.","ista":"Hikaru I, Wojtan C, Thuerey N, Igarashi T, Ando R. 2020. Simulating liquids on dynamically warping grids. IEEE Transactions on Visualization and Computer Graphics. 26(6), 2288–2302.","short":"I. Hikaru, C. Wojtan, N. Thuerey, T. Igarashi, R. Ando, IEEE Transactions on Visualization and Computer Graphics 26 (2020) 2288–2302.","mla":"Hikaru, Ibayashi, et al. “Simulating Liquids on Dynamically Warping Grids.” IEEE Transactions on Visualization and Computer Graphics, vol. 26, no. 6, IEEE, 2020, pp. 2288–302, doi:10.1109/TVCG.2018.2883628.","ama":"Hikaru I, Wojtan C, Thuerey N, Igarashi T, Ando R. Simulating liquids on dynamically warping grids. IEEE Transactions on Visualization and Computer Graphics. 2020;26(6):2288-2302. doi:10.1109/TVCG.2018.2883628"},"file":[{"checksum":"8d4c55443a0ee335bb5bb652de503042","file_id":"8626","creator":"wojtan","access_level":"open_access","file_name":"preprint.pdf","relation":"main_file","date_created":"2020-10-08T08:34:53Z","file_size":21910098,"success":1,"date_updated":"2020-10-08T08:34:53Z","content_type":"application/pdf"}],"file_date_updated":"2020-10-08T08:34:53Z","acknowledged_ssus":[{"_id":"ScienComp"}],"doi":"10.1109/TVCG.2018.2883628","user_id":"c635000d-4b10-11ee-a964-aac5a93f6ac1","abstract":[{"lang":"eng","text":"We introduce dynamically warping grids for adaptive liquid simulation. Our primary contributions are a strategy for dynamically deforming regular grids over the course of a simulation and a method for efficiently utilizing these deforming grids for liquid simulation. Prior work has shown that unstructured grids are very effective for adaptive fluid simulations. However, unstructured grids often lead to complicated implementations and a poor cache hit rate due to inconsistent memory access. Regular grids, on the other hand, provide a fast, fixed memory access pattern and straightforward implementation. Our method combines the advantages of both: we leverage the simplicity of regular grids while still achieving practical and controllable spatial adaptivity. We demonstrate that our method enables adaptive simulations that are fast, flexible, and robust to null-space issues. At the same time, our method is simple to implement and takes advantage of existing highly-tuned algorithms."}],"page":"2288-2302","article_type":"original","oa":1,"month":"06","isi":1,"external_id":{"isi":["000532295600014"],"pmid":["30507534"]},"date_published":"2020-06-01T00:00:00Z","language":[{"iso":"eng"}],"date_updated":"2023-09-18T09:30:01Z","day":"01","ddc":["006"],"_id":"5681","publication_identifier":{"issn":["10772626"],"eissn":["19410506"]},"quality_controlled":"1","pmid":1,"acknowledgement":"This work was partially supported by JSPS Grant-in-Aid forYoung Scientists (Start-up) 16H07410, the ERC StartingGrantsrealFlow(StG-2015-637014) andBigSplash(StG-2014-638176). This research was supported by the Scientific Ser-vice Units (SSU) of IST Austria through resources providedby Scientific Computing. We would like to express my grati-tude to Nobuyuki Umetani and Tomas Skrivan for insight-ful discussion.","article_processing_charge":"No","scopus_import":"1","type":"journal_article","has_accepted_license":"1","volume":26,"author":[{"first_name":"Ibayashi","full_name":"Hikaru, Ibayashi","last_name":"Hikaru"},{"last_name":"Wojtan","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","first_name":"Christopher J","orcid":"0000-0001-6646-5546"},{"first_name":"Nils","full_name":"Thuerey, Nils","last_name":"Thuerey"},{"full_name":"Igarashi, Takeo","last_name":"Igarashi","first_name":"Takeo"},{"first_name":"Ryoichi","last_name":"Ando","full_name":"Ando, Ryoichi"}],"publisher":"IEEE"},{"ddc":["000"],"article_number":"31","_id":"8384","publication_identifier":{"eissn":["15577368"],"issn":["07300301"]},"quality_controlled":"1","acknowledgement":"We wish to thank the anonymous reviewers and the members of the Visual Computing Group at IST Austria for their valuable feedback, especially Camille Schreck for her help in rendering. This research was supported by the Scientific Service Units (SSU) of IST Austria through resources provided by Scientific Computing. We would like to thank the authors of [Belcour and Barla 2017] for providing their implementation, the authors of [Atkins and Elliott 2010] and [Seychelles et al. 2008] for allowing us to use their results, and Rok Grah for helpful discussions. Finally, we thank Ryoichi Ando for many discussions from the beginning of the project that resulted in important contents of the paper including our formulation, numerical scheme, and initial implementation. This project has received funding from the\r\nEuropean Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 638176.","article_processing_charge":"No","type":"journal_article","scopus_import":"1","has_accepted_license":"1","volume":39,"author":[{"first_name":"Sadashige","id":"6F7C4B96-A8E9-11E9-A7CA-09ECE5697425","full_name":"Ishida, Sadashige","last_name":"Ishida"},{"last_name":"Synak","id":"331776E2-F248-11E8-B48F-1D18A9856A87","full_name":"Synak, Peter","first_name":"Peter"},{"first_name":"Fumiya","full_name":"Narita, Fumiya","last_name":"Narita"},{"last_name":"Hachisuka","full_name":"Hachisuka, Toshiya","first_name":"Toshiya"},{"first_name":"Christopher J","orcid":"0000-0001-6646-5546","last_name":"Wojtan","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87"}],"publisher":"Association for Computing Machinery","month":"07","isi":1,"external_id":{"isi":["000583700300004"]},"date_published":"2020-07-08T00:00:00Z","language":[{"iso":"eng"}],"date_updated":"2024-02-28T12:57:31Z","day":"08","oa_version":"Submitted Version","main_file_link":[{"open_access":"1","url":"https://doi.org/10.1145/3386569.3392405"}],"ec_funded":1,"title":"A model for soap film dynamics with evolving thickness","date_created":"2020-09-13T22:01:18Z","citation":{"short":"S. Ishida, P. Synak, F. Narita, T. Hachisuka, C. Wojtan, ACM Transactions on Graphics 39 (2020).","mla":"Ishida, Sadashige, et al. “A Model for Soap Film Dynamics with Evolving Thickness.” ACM Transactions on Graphics, vol. 39, no. 4, 31, Association for Computing Machinery, 2020, doi:10.1145/3386569.3392405.","ama":"Ishida S, Synak P, Narita F, Hachisuka T, Wojtan C. A model for soap film dynamics with evolving thickness. ACM Transactions on Graphics. 2020;39(4). doi:10.1145/3386569.3392405","apa":"Ishida, S., Synak, P., Narita, F., Hachisuka, T., & Wojtan, C. (2020). A model for soap film dynamics with evolving thickness. ACM Transactions on Graphics. Association for Computing Machinery. https://doi.org/10.1145/3386569.3392405","ieee":"S. Ishida, P. Synak, F. Narita, T. Hachisuka, and C. Wojtan, “A model for soap film dynamics with evolving thickness,” ACM Transactions on Graphics, vol. 39, no. 4. Association for Computing Machinery, 2020.","ista":"Ishida S, Synak P, Narita F, Hachisuka T, Wojtan C. 2020. A model for soap film dynamics with evolving thickness. ACM Transactions on Graphics. 39(4), 31.","chicago":"Ishida, Sadashige, Peter Synak, Fumiya Narita, Toshiya Hachisuka, and Chris Wojtan. “A Model for Soap Film Dynamics with Evolving Thickness.” ACM Transactions on Graphics. Association for Computing Machinery, 2020. https://doi.org/10.1145/3386569.3392405."},"project":[{"grant_number":"638176","name":"Efficient Simulation of Natural Phenomena at Extremely Large Scales","call_identifier":"H2020","_id":"2533E772-B435-11E9-9278-68D0E5697425"}],"file":[{"creator":"dernst","access_level":"open_access","file_name":"2020_soapfilm_submitted.pdf","relation":"main_file","file_size":14935529,"date_created":"2020-11-23T09:03:19Z","checksum":"813831ca91319d794d9748c276b24578","file_id":"8795","content_type":"application/pdf","success":1,"date_updated":"2020-11-23T09:03:19Z"}],"doi":"10.1145/3386569.3392405","acknowledged_ssus":[{"_id":"ScienComp"}],"file_date_updated":"2020-11-23T09:03:19Z","abstract":[{"text":"Previous research on animations of soap bubbles, films, and foams largely focuses on the motion and geometric shape of the bubble surface. These works neglect the evolution of the bubble’s thickness, which is normally responsible for visual phenomena like surface vortices, Newton’s interference patterns, capillary waves, and deformation-dependent rupturing of films in a foam. In this paper, we model these natural phenomena by introducing the film thickness as a reduced degree of freedom in the Navier-Stokes equations and deriving their equations of motion. We discretize the equations on a nonmanifold triangle mesh surface and couple it to an existing bubble solver. In doing so, we also introduce an incompressible fluid solver for 2.5D films and a novel advection algorithm for convecting fields across non-manifold surface junctions. Our simulations enhance state-of-the-art bubble solvers with additional effects caused by convection, rippling, draining, and evaporation of the thin film.","lang":"eng"}],"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","article_type":"original","oa":1,"publication":"ACM Transactions on Graphics","intvolume":" 39","issue":"4","year":"2020","publication_status":"published","status":"public","department":[{"_id":"ChWo"}]},{"external_id":{"isi":["000583700300021"]},"date_published":"2020-07-08T00:00:00Z","language":[{"iso":"eng"}],"month":"07","isi":1,"day":"08","date_updated":"2024-02-28T12:57:47Z","quality_controlled":"1","acknowledgement":"We wish to thank the anonymous reviewers and the members of the Visual Computing Group at IST Austria for their valuable feedback. We also thank the creators of the Berkeley Garment Library [de Joya et al. 2012] for providing garment meshes, [Krishnamurthy and Levoy 1996] and [Turk and Levoy 1994] for the armadillo and bunny meshes, the creators of libWetCloth [Fei et al. 2018] for their implementation of discrete elastic rod forces, and Tomáš Skřivan for\r\ninspiring discussions and help with Mathematica code generation. 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. Rahul Narain is supported by a Pankaj Gupta Young Faculty Fellowship and a gift from Adobe Inc.","article_processing_charge":"No","ddc":["000"],"article_number":"48","_id":"8385","publication_identifier":{"eissn":["15577368"],"issn":["07300301"]},"author":[{"last_name":"Sperl","id":"4DD40360-F248-11E8-B48F-1D18A9856A87","full_name":"Sperl, Georg","first_name":"Georg"},{"first_name":"Rahul","full_name":"Narain, Rahul","last_name":"Narain"},{"id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J","last_name":"Wojtan","orcid":"0000-0001-6646-5546","first_name":"Christopher J"}],"publisher":"Association for Computing Machinery","type":"journal_article","scopus_import":"1","has_accepted_license":"1","volume":39,"issue":"4","publication":"ACM Transactions on Graphics","intvolume":" 39","publication_status":"published","status":"public","department":[{"_id":"ChWo"}],"year":"2020","date_created":"2020-09-13T22:01:18Z","title":"Homogenized yarn-level cloth","citation":{"apa":"Sperl, G., Narain, R., & Wojtan, C. (2020). Homogenized yarn-level cloth. ACM Transactions on Graphics. Association for Computing Machinery. https://doi.org/10.1145/3386569.3392412","ieee":"G. Sperl, R. Narain, and C. Wojtan, “Homogenized yarn-level cloth,” ACM Transactions on Graphics, vol. 39, no. 4. Association for Computing Machinery, 2020.","ista":"Sperl G, Narain R, Wojtan C. 2020. Homogenized yarn-level cloth. ACM Transactions on Graphics. 39(4), 48.","chicago":"Sperl, Georg, Rahul Narain, and Chris Wojtan. “Homogenized Yarn-Level Cloth.” ACM Transactions on Graphics. Association for Computing Machinery, 2020. https://doi.org/10.1145/3386569.3392412.","mla":"Sperl, Georg, et al. “Homogenized Yarn-Level Cloth.” ACM Transactions on Graphics, vol. 39, no. 4, 48, Association for Computing Machinery, 2020, doi:10.1145/3386569.3392412.","short":"G. Sperl, R. Narain, C. Wojtan, ACM Transactions on Graphics 39 (2020).","ama":"Sperl G, Narain R, Wojtan C. Homogenized yarn-level cloth. ACM Transactions on Graphics. 2020;39(4). doi:10.1145/3386569.3392412"},"oa_version":"Submitted Version","main_file_link":[{"open_access":"1","url":"https://doi.org/10.1145/3386569.3392412"}],"related_material":{"record":[{"relation":"dissertation_contains","status":"public","id":"12358"}]},"ec_funded":1,"article_type":"original","oa":1,"project":[{"call_identifier":"H2020","name":"Efficient Simulation of Natural Phenomena at Extremely Large Scales","grant_number":"638176","_id":"2533E772-B435-11E9-9278-68D0E5697425"}],"file":[{"success":1,"date_updated":"2020-11-23T09:01:22Z","content_type":"application/pdf","file_id":"8794","checksum":"cf4c1d361c3196c4bd424520a5588205","relation":"main_file","file_size":38922662,"date_created":"2020-11-23T09:01:22Z","creator":"dernst","access_level":"open_access","file_name":"2020_hylc_submitted.pdf"}],"file_date_updated":"2020-11-23T09:01:22Z","doi":"10.1145/3386569.3392412","acknowledged_ssus":[{"_id":"ScienComp"}],"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","abstract":[{"text":"We present a method for animating yarn-level cloth effects using a thin-shell solver. We accomplish this through numerical homogenization: we first use a large number of yarn-level simulations to build a model of the potential energy density of the cloth, and then use this energy density function to compute forces in a thin shell simulator. We model several yarn-based materials, including both woven and knitted fabrics. Our model faithfully reproduces expected effects like the stiffness of woven fabrics, and the highly deformable nature and anisotropy of knitted fabrics. Our approach does not require any real-world experiments nor measurements; because the method is based entirely on simulations, it can generate entirely new material models quickly, without the need for testing apparatuses or human intervention. We provide data-driven models of several woven and knitted fabrics, which can be used for efficient simulation with an off-the-shelf cloth solver.","lang":"eng"}]},{"article_processing_charge":"No","quality_controlled":"1","_id":"8766","author":[{"first_name":"Stefan","id":"44D6411A-F248-11E8-B48F-1D18A9856A87","full_name":"Jeschke, Stefan","last_name":"Jeschke"},{"first_name":"Christian","id":"400429CC-F248-11E8-B48F-1D18A9856A87","full_name":"Hafner, Christian","last_name":"Hafner"},{"last_name":"Chentanez","full_name":"Chentanez, Nuttapong","first_name":"Nuttapong"},{"full_name":"Macklin, Miles","last_name":"Macklin","first_name":"Miles"},{"first_name":"Matthias","full_name":"Müller-Fischer, Matthias","last_name":"Müller-Fischer"},{"full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","last_name":"Wojtan","orcid":"0000-0001-6646-5546","first_name":"Christopher J"}],"publisher":"Wiley","volume":39,"scopus_import":"1","type":"journal_article","language":[{"iso":"eng"}],"conference":{"end_date":"2020-10-09","start_date":"2020-10-06","name":"SCA: Symposium on Computer Animation","location":"Online Symposium"},"external_id":{"isi":["000591780400005"]},"date_published":"2020-12-01T00:00:00Z","isi":1,"month":"12","day":"01","date_updated":"2024-02-28T13:58:11Z","citation":{"ama":"Jeschke S, Hafner C, Chentanez N, Macklin M, Müller-Fischer M, Wojtan C. Making procedural water waves boundary-aware. Computer Graphics forum. 2020;39(8):47-54. doi:10.1111/cgf.14100","mla":"Jeschke, Stefan, et al. “Making Procedural Water Waves Boundary-Aware.” Computer Graphics Forum, vol. 39, no. 8, Wiley, 2020, pp. 47–54, doi:10.1111/cgf.14100.","short":"S. Jeschke, C. Hafner, N. Chentanez, M. Macklin, M. Müller-Fischer, C. Wojtan, Computer Graphics Forum 39 (2020) 47–54.","chicago":"Jeschke, Stefan, Christian Hafner, Nuttapong Chentanez, Miles Macklin, Matthias Müller-Fischer, and Chris Wojtan. “Making Procedural Water Waves Boundary-Aware.” Computer Graphics Forum. Wiley, 2020. https://doi.org/10.1111/cgf.14100.","ista":"Jeschke S, Hafner C, Chentanez N, Macklin M, Müller-Fischer M, Wojtan C. 2020. Making procedural water waves boundary-aware. Computer Graphics forum. 39(8), 47–54.","ieee":"S. Jeschke, C. Hafner, N. Chentanez, M. Macklin, M. Müller-Fischer, and C. Wojtan, “Making procedural water waves boundary-aware,” Computer Graphics forum, vol. 39, no. 8. Wiley, pp. 47–54, 2020.","apa":"Jeschke, S., Hafner, C., Chentanez, N., Macklin, M., Müller-Fischer, M., & Wojtan, C. (2020). Making procedural water waves boundary-aware. Computer Graphics Forum. Online Symposium: Wiley. https://doi.org/10.1111/cgf.14100"},"date_created":"2020-11-17T10:47:48Z","title":"Making procedural water waves boundary-aware","ec_funded":1,"oa_version":"None","article_type":"original","page":"47-54","doi":"10.1111/cgf.14100","abstract":[{"text":"The “procedural” approach to animating ocean waves is the dominant algorithm for animating larger bodies of water in\r\ninteractive applications as well as in off-line productions — it provides high visual quality with a low computational demand. In this paper, we widen the applicability of procedural water wave animation with an extension that guarantees the satisfaction of boundary conditions imposed by terrain while still approximating physical wave behavior. In combination with a particle system that models wave breaking, foam, and spray, this allows us to naturally model waves interacting with beaches and rocks. Our system is able to animate waves at large scales at interactive frame rates on a commodity PC.","lang":"eng"}],"user_id":"2EBD1598-F248-11E8-B48F-1D18A9856A87","project":[{"grant_number":"638176","name":"Efficient Simulation of Natural Phenomena at Extremely Large Scales","call_identifier":"H2020","_id":"2533E772-B435-11E9-9278-68D0E5697425"},{"call_identifier":"H2020","name":"MATERIALIZABLE: Intelligent fabrication-oriented Computational Design and Modeling","grant_number":"715767","_id":"24F9549A-B435-11E9-9278-68D0E5697425"}],"issue":"8","intvolume":" 39","publication":"Computer Graphics forum","department":[{"_id":"ChWo"},{"_id":"BeBi"}],"status":"public","publication_status":"published","year":"2020"},{"date_updated":"2023-08-25T10:18:46Z","day":"01","month":"07","isi":1,"date_published":"2019-07-01T00:00:00Z","external_id":{"isi":["000475740600104"]},"language":[{"iso":"eng"}],"type":"journal_article","scopus_import":"1","volume":38,"has_accepted_license":"1","publisher":"ACM","author":[{"first_name":"Camille","id":"2B14B676-F248-11E8-B48F-1D18A9856A87","full_name":"Schreck, Camille","last_name":"Schreck"},{"first_name":"Christian","last_name":"Hafner","id":"400429CC-F248-11E8-B48F-1D18A9856A87","full_name":"Hafner, Christian"},{"last_name":"Wojtan","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","first_name":"Christopher J","orcid":"0000-0001-6646-5546"}],"ddc":["000","005"],"article_number":"130","_id":"6442","quality_controlled":"1","article_processing_charge":"No","year":"2019","publication_status":"published","department":[{"_id":"ChWo"}],"status":"public","publication":"ACM Transactions on Graphics","intvolume":" 38","issue":"4","file":[{"creator":"dernst","file_name":"2019_ACM_Schreck.pdf","access_level":"open_access","relation":"main_file","date_created":"2019-05-14T07:03:55Z","file_size":44328918,"checksum":"1b737dfe3e051aba8f3f4ab1dceda673","file_id":"6443","content_type":"application/pdf","date_updated":"2020-07-14T12:47:30Z"}],"project":[{"_id":"2533E772-B435-11E9-9278-68D0E5697425","name":"Efficient Simulation of Natural Phenomena at Extremely Large Scales","grant_number":"638176","call_identifier":"H2020"},{"grant_number":"715767","name":"MATERIALIZABLE: Intelligent fabrication-oriented Computational Design and Modeling","call_identifier":"H2020","_id":"24F9549A-B435-11E9-9278-68D0E5697425"},{"_id":"2564DBCA-B435-11E9-9278-68D0E5697425","name":"International IST Doctoral Program","grant_number":"665385","call_identifier":"H2020"}],"abstract":[{"text":"This paper investigates the use of fundamental solutions for animating detailed linear water surface waves. We first propose an analytical solution for efficiently animating circular ripples in closed form. We then show how to adapt the method of fundamental solutions (MFS) to create ambient waves interacting with complex obstacles. Subsequently, we present a novel wavelet-based discretization which outperforms the state of the art MFS approach for simulating time-varying water surface waves with moving obstacles. Our results feature high-resolution spatial details, interactions with complex boundaries, and large open ocean domains. Our method compares favorably with previous work as well as known analytical solutions. We also present comparisons between our method and real world examples.","lang":"eng"}],"user_id":"4359f0d1-fa6c-11eb-b949-802e58b17ae8","doi":"10.1145/3306346.3323002","acknowledged_ssus":[{"_id":"ScienComp"}],"file_date_updated":"2020-07-14T12:47:30Z","oa":1,"oa_version":"Submitted Version","ec_funded":1,"related_material":{"link":[{"url":"https://ist.ac.at/en/news/new-method-makes-realistic-water-wave-animations-more-efficient/","description":"News on IST Homepage","relation":"press_release"}]},"date_created":"2019-05-14T07:04:06Z","title":"Fundamental solutions for water wave animation","citation":{"ieee":"C. Schreck, C. Hafner, and C. Wojtan, “Fundamental solutions for water wave animation,” ACM Transactions on Graphics, vol. 38, no. 4. ACM, 2019.","apa":"Schreck, C., Hafner, C., & Wojtan, C. (2019). Fundamental solutions for water wave animation. ACM Transactions on Graphics. ACM. https://doi.org/10.1145/3306346.3323002","chicago":"Schreck, Camille, Christian Hafner, and Chris Wojtan. “Fundamental Solutions for Water Wave Animation.” ACM Transactions on Graphics. ACM, 2019. https://doi.org/10.1145/3306346.3323002.","ista":"Schreck C, Hafner C, Wojtan C. 2019. Fundamental solutions for water wave animation. ACM Transactions on Graphics. 38(4), 130.","short":"C. Schreck, C. Hafner, C. Wojtan, ACM Transactions on Graphics 38 (2019).","mla":"Schreck, Camille, et al. “Fundamental Solutions for Water Wave Animation.” ACM Transactions on Graphics, vol. 38, no. 4, 130, ACM, 2019, doi:10.1145/3306346.3323002.","ama":"Schreck C, Hafner C, Wojtan C. Fundamental solutions for water wave animation. ACM Transactions on Graphics. 2019;38(4). doi:10.1145/3306346.3323002"}},{"volume":37,"has_accepted_license":"1","scopus_import":"1","type":"journal_article","author":[{"last_name":"Sato","full_name":"Sato, Takahiro","first_name":"Takahiro"},{"id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J","last_name":"Wojtan","orcid":"0000-0001-6646-5546","first_name":"Christopher J"},{"first_name":"Nils","last_name":"Thuerey","full_name":"Thuerey, Nils"},{"full_name":"Igarashi, Takeo","last_name":"Igarashi","first_name":"Takeo"},{"first_name":"Ryoichi","last_name":"Ando","full_name":"Ando, Ryoichi"}],"publisher":"Wiley","_id":"135","publication_identifier":{"issn":["0167-7055"]},"ddc":["006"],"article_processing_charge":"No","quality_controlled":"1","date_updated":"2023-09-11T14:00:26Z","day":"22","isi":1,"month":"05","language":[{"iso":"eng"}],"external_id":{"isi":["000434085600016"]},"date_published":"2018-05-22T00:00:00Z","doi":"10.1111/cgf.13351","file_date_updated":"2020-10-08T08:38:23Z","abstract":[{"lang":"eng","text":"The Fluid Implicit Particle method (FLIP) reduces numerical dissipation by combining particles with grids. To improve performance, the subsequent narrow band FLIP method (NB‐FLIP) uses a FLIP‐based fluid simulation only near the liquid surface and a traditional grid‐based fluid simulation away from the surface. This spatially‐limited FLIP simulation significantly reduces the number of particles and alleviates a computational bottleneck. In this paper, we extend the NB‐FLIP idea even further, by allowing a simulation to transition between a FLIP‐like fluid simulation and a grid‐based simulation in arbitrary locations, not just near the surface. This approach leads to even more savings in memory and computation, because we can concentrate the particles only in areas where they are needed. More importantly, this new method allows us to seamlessly transition to smooth implicit surface geometry wherever the particle‐based simulation is unnecessary. Consequently, our method leads to a practical algorithm for avoiding the noisy surface artifacts associated with particle‐based liquid simulations, while simultaneously maintaining the benefits of a FLIP simulation in regions of dynamic motion."}],"user_id":"c635000d-4b10-11ee-a964-aac5a93f6ac1","file":[{"file_id":"8627","checksum":"8edb90da8a72395eb5d970580e0925b6","date_created":"2020-10-08T08:38:23Z","file_size":54309947,"relation":"main_file","file_name":"exnbflip.pdf","access_level":"open_access","creator":"wojtan","date_updated":"2020-10-08T08:38:23Z","success":1,"content_type":"application/pdf"}],"project":[{"grant_number":"638176","name":"Efficient Simulation of Natural Phenomena at Extremely Large Scales","call_identifier":"H2020","_id":"2533E772-B435-11E9-9278-68D0E5697425"}],"oa":1,"article_type":"original","page":"169 - 177","ec_funded":1,"oa_version":"Submitted Version","alternative_title":["Eurographics"],"citation":{"mla":"Sato, Takahiro, et al. “Extended Narrow Band FLIP for Liquid Simulations.” Computer Graphics Forum, vol. 37, no. 2, Wiley, 2018, pp. 169–77, doi:10.1111/cgf.13351.","short":"T. Sato, C. Wojtan, N. Thuerey, T. Igarashi, R. Ando, Computer Graphics Forum 37 (2018) 169–177.","ama":"Sato T, Wojtan C, Thuerey N, Igarashi T, Ando R. Extended narrow band FLIP for liquid simulations. Computer Graphics Forum. 2018;37(2):169-177. doi:10.1111/cgf.13351","apa":"Sato, T., Wojtan, C., Thuerey, N., Igarashi, T., & Ando, R. (2018). Extended narrow band FLIP for liquid simulations. Computer Graphics Forum. Wiley. https://doi.org/10.1111/cgf.13351","ieee":"T. Sato, C. Wojtan, N. Thuerey, T. Igarashi, and R. Ando, “Extended narrow band FLIP for liquid simulations,” Computer Graphics Forum, vol. 37, no. 2. Wiley, pp. 169–177, 2018.","ista":"Sato T, Wojtan C, Thuerey N, Igarashi T, Ando R. 2018. Extended narrow band FLIP for liquid simulations. Computer Graphics Forum. 37(2), 169–177.","chicago":"Sato, Takahiro, Chris Wojtan, Nils Thuerey, Takeo Igarashi, and Ryoichi Ando. “Extended Narrow Band FLIP for Liquid Simulations.” Computer Graphics Forum. Wiley, 2018. https://doi.org/10.1111/cgf.13351."},"title":"Extended narrow band FLIP for liquid simulations","date_created":"2018-12-11T11:44:49Z","year":"2018","department":[{"_id":"ChWo"}],"status":"public","publication_status":"published","intvolume":" 37","publication":"Computer Graphics Forum","issue":"2"},{"month":"07","isi":1,"date_published":"2018-07-30T00:00:00Z","external_id":{"isi":["000448185000055"]},"language":[{"iso":"eng"}],"date_updated":"2024-02-28T13:58:51Z","day":"30","license":"https://creativecommons.org/licenses/by-nc-sa/4.0/","ddc":["000"],"article_number":"94","_id":"134","quality_controlled":"1","article_processing_charge":"No","type":"journal_article","scopus_import":"1","has_accepted_license":"1","volume":37,"publisher":"ACM","author":[{"last_name":"Jeschke","id":"44D6411A-F248-11E8-B48F-1D18A9856A87","full_name":"Jeschke, Stefan","first_name":"Stefan"},{"first_name":"Tomas","last_name":"Skrivan","id":"486A5A46-F248-11E8-B48F-1D18A9856A87","full_name":"Skrivan, Tomas"},{"full_name":"Mueller Fischer, Matthias","last_name":"Mueller Fischer","first_name":"Matthias"},{"first_name":"Nuttapong","last_name":"Chentanez","full_name":"Chentanez, Nuttapong"},{"last_name":"Macklin","full_name":"Macklin, Miles","first_name":"Miles"},{"first_name":"Christopher J","orcid":"0000-0001-6646-5546","last_name":"Wojtan","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J"}],"publication":"ACM Transactions on Graphics","intvolume":" 37","issue":"4","year":"2018","publist_id":"7789","publication_status":"published","status":"public","department":[{"_id":"ChWo"}],"tmp":{"name":"Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)","short":"CC BY-NC-SA (4.0)","legal_code_url":"https://creativecommons.org/licenses/by-nc-sa/4.0/legalcode","image":"/images/cc_by_nc_sa.png"},"oa_version":"Published Version","ec_funded":1,"related_material":{"link":[{"url":"https://ist.ac.at/en/news/new-water-simulation-captures-small-details-even-in-large-scenes/","description":"News on IST Homepage","relation":"press_release"}]},"title":"Water surface wavelets","date_created":"2018-12-11T11:44:48Z","citation":{"ama":"Jeschke S, Skrivan T, Mueller Fischer M, Chentanez N, Macklin M, Wojtan C. Water surface wavelets. ACM Transactions on Graphics. 2018;37(4). doi:10.1145/3197517.3201336","mla":"Jeschke, Stefan, et al. “Water Surface Wavelets.” ACM Transactions on Graphics, vol. 37, no. 4, 94, ACM, 2018, doi:10.1145/3197517.3201336.","short":"S. Jeschke, T. Skrivan, M. Mueller Fischer, N. Chentanez, M. Macklin, C. Wojtan, ACM Transactions on Graphics 37 (2018).","ista":"Jeschke S, Skrivan T, Mueller Fischer M, Chentanez N, Macklin M, Wojtan C. 2018. Water surface wavelets. ACM Transactions on Graphics. 37(4), 94.","chicago":"Jeschke, Stefan, Tomas Skrivan, Matthias Mueller Fischer, Nuttapong Chentanez, Miles Macklin, and Chris Wojtan. “Water Surface Wavelets.” ACM Transactions on Graphics. ACM, 2018. https://doi.org/10.1145/3197517.3201336.","apa":"Jeschke, S., Skrivan, T., Mueller Fischer, M., Chentanez, N., Macklin, M., & Wojtan, C. (2018). Water surface wavelets. ACM Transactions on Graphics. ACM. https://doi.org/10.1145/3197517.3201336","ieee":"S. Jeschke, T. Skrivan, M. Mueller Fischer, N. Chentanez, M. Macklin, and C. Wojtan, “Water surface wavelets,” ACM Transactions on Graphics, vol. 37, no. 4. ACM, 2018."},"alternative_title":["SIGGRAPH"],"project":[{"_id":"2533E772-B435-11E9-9278-68D0E5697425","name":"Efficient Simulation of Natural Phenomena at Extremely Large Scales","grant_number":"638176","call_identifier":"H2020"},{"grant_number":"665385","name":"International IST Doctoral Program","call_identifier":"H2020","_id":"2564DBCA-B435-11E9-9278-68D0E5697425"}],"file":[{"relation":"main_file","file_size":22185016,"date_created":"2018-12-18T09:59:23Z","creator":"dernst","access_level":"open_access","file_name":"2018_ACM_Jeschke.pdf","file_id":"5744","checksum":"db75ebabe2ec432bf41389e614d6ef62","content_type":"application/pdf","date_updated":"2020-07-14T12:44:45Z"}],"user_id":"2EBD1598-F248-11E8-B48F-1D18A9856A87","abstract":[{"lang":"eng","text":"The current state of the art in real-time two-dimensional water wave simulation requires developers to choose between efficient Fourier-based methods, which lack interactions with moving obstacles, and finite-difference or finite element methods, which handle environmental interactions but are significantly more expensive. This paper attempts to bridge this long-standing gap between complexity and performance, by proposing a new wave simulation method that can faithfully simulate wave interactions with moving obstacles in real time while simultaneously preserving minute details and accommodating very large simulation domains.\r\n\r\nPrevious methods for simulating 2D water waves directly compute the change in height of the water surface, a strategy which imposes limitations based on the CFL condition (fast moving waves require small time steps) and Nyquist's limit (small wave details require closely-spaced simulation variables). This paper proposes a novel wavelet transformation that discretizes the liquid motion in terms of amplitude-like functions that vary over space, frequency, and direction, effectively generalizing Fourier-based methods to handle local interactions. Because these new variables change much more slowly over space than the original water height function, our change of variables drastically reduces the limitations of the CFL condition and Nyquist limit, allowing us to simulate highly detailed water waves at very large visual resolutions. Our discretization is amenable to fast summation and easy to parallelize. We also present basic extensions like pre-computed wave paths and two-way solid fluid coupling. Finally, we argue that our discretization provides a convenient set of variables for artistic manipulation, which we illustrate with a novel wave-painting interface."}],"file_date_updated":"2020-07-14T12:44:45Z","acknowledged_ssus":[{"_id":"ScienComp"}],"doi":"10.1145/3197517.3201336","oa":1},{"month":"07","language":[{"iso":"eng"}],"date_published":"2017-07-01T00:00:00Z","date_updated":"2023-02-23T12:20:26Z","day":"01","publication_identifier":{"issn":["07300301"]},"_id":"470","ddc":["006"],"article_number":"103","article_processing_charge":"Yes (in subscription journal)","quality_controlled":"1","volume":36,"has_accepted_license":"1","scopus_import":1,"type":"journal_article","publisher":"ACM","author":[{"id":"44D6411A-F248-11E8-B48F-1D18A9856A87","full_name":"Jeschke, Stefan","last_name":"Jeschke","first_name":"Stefan"},{"orcid":"0000-0001-6646-5546","first_name":"Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J","last_name":"Wojtan"}],"intvolume":" 36","publication":"ACM Transactions on Graphics","issue":"4","year":"2017","publist_id":"7350","status":"public","department":[{"_id":"ChWo"}],"publication_status":"published","ec_funded":1,"oa_version":"Published Version","citation":{"mla":"Jeschke, Stefan, and Chris Wojtan. “Water Wave Packets.” ACM Transactions on Graphics, vol. 36, no. 4, 103, ACM, 2017, doi:10.1145/3072959.3073678.","short":"S. Jeschke, C. Wojtan, ACM Transactions on Graphics 36 (2017).","ama":"Jeschke S, Wojtan C. Water wave packets. ACM Transactions on Graphics. 2017;36(4). doi:10.1145/3072959.3073678","ieee":"S. Jeschke and C. Wojtan, “Water wave packets,” ACM Transactions on Graphics, vol. 36, no. 4. ACM, 2017.","apa":"Jeschke, S., & Wojtan, C. (2017). Water wave packets. ACM Transactions on Graphics. ACM. https://doi.org/10.1145/3072959.3073678","chicago":"Jeschke, Stefan, and Chris Wojtan. “Water Wave Packets.” ACM Transactions on Graphics. ACM, 2017. https://doi.org/10.1145/3072959.3073678.","ista":"Jeschke S, Wojtan C. 2017. Water wave packets. ACM Transactions on Graphics. 36(4), 103."},"title":"Water wave packets","date_created":"2018-12-11T11:46:39Z","abstract":[{"lang":"eng","text":"This paper presents a method for simulating water surface waves as a displacement field on a 2D domain. Our method relies on Lagrangian particles that carry packets of water wave energy; each packet carries information about an entire group of wave trains, as opposed to only a single wave crest. Our approach is unconditionally stable and can simulate high resolution geometric details. This approach also presents a straightforward interface for artistic control, because it is essentially a particle system with intuitive parameters like wavelength and amplitude. Our implementation parallelizes well and runs in real time for moderately challenging scenarios."}],"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","acknowledged_ssus":[{"_id":"ScienComp"}],"doi":"10.1145/3072959.3073678","file_date_updated":"2020-07-14T12:46:34Z","project":[{"call_identifier":"H2020","grant_number":"638176","name":"Efficient Simulation of Natural Phenomena at Extremely Large Scales","_id":"2533E772-B435-11E9-9278-68D0E5697425"}],"file":[{"date_updated":"2020-07-14T12:46:34Z","content_type":"application/pdf","file_id":"7359","checksum":"82a3b2bfeee4ddef16ecc21675d1a48a","relation":"main_file","file_size":13131683,"date_created":"2020-01-24T09:32:35Z","creator":"wojtan","access_level":"open_access","file_name":"wavepackets_final.pdf"}],"article_type":"original","oa":1},{"publication_status":"published","department":[{"_id":"ChWo"}],"status":"public","year":"2017","publist_id":"5873","issue":"6","publication":"Computer Graphics Forum","pubrep_id":"634","intvolume":" 36","page":"312 - 337","oa":1,"file":[{"date_updated":"2020-07-14T12:44:47Z","content_type":"application/pdf","checksum":"7676e9a9ead6d58c3000988c97deb2ef","file_id":"5208","access_level":"open_access","file_name":"IST-2016-634-v1+1_starAdaptivity-cgf.pdf","creator":"system","date_created":"2018-12-12T10:16:21Z","file_size":1434439,"relation":"main_file"}],"user_id":"c635000d-4b10-11ee-a964-aac5a93f6ac1","abstract":[{"text":"One of the major challenges in physically based modelling is making simulations efficient. Adaptive models provide an essential solution to these efficiency goals. These models are able to self-adapt in space and time, attempting to provide the best possible compromise between accuracy and speed. This survey reviews the adaptive solutions proposed so far in computer graphics. Models are classified according to the strategy they use for adaptation, from time-stepping and freezing techniques to geometric adaptivity in the form of structured grids, meshes and particles. Applications range from fluids, through deformable bodies, to articulated solids.","lang":"eng"}],"file_date_updated":"2020-07-14T12:44:47Z","doi":"10.1111/cgf.12941","title":"Adaptive physically based models in computer graphics","date_created":"2018-12-11T11:51:37Z","citation":{"ama":"Manteaux P, Wojtan C, Narain R, Redon S, Faure F, Cani M. Adaptive physically based models in computer graphics. Computer Graphics Forum. 2017;36(6):312-337. doi:10.1111/cgf.12941","short":"P. Manteaux, C. Wojtan, R. Narain, S. Redon, F. Faure, M. Cani, Computer Graphics Forum 36 (2017) 312–337.","mla":"Manteaux, Pierre, et al. “Adaptive Physically Based Models in Computer Graphics.” Computer Graphics Forum, vol. 36, no. 6, Wiley-Blackwell, 2017, pp. 312–37, doi:10.1111/cgf.12941.","ista":"Manteaux P, Wojtan C, Narain R, Redon S, Faure F, Cani M. 2017. Adaptive physically based models in computer graphics. Computer Graphics Forum. 36(6), 312–337.","chicago":"Manteaux, Pierre, Chris Wojtan, Rahul Narain, Stéphane Redon, François Faure, and Marie Cani. “Adaptive Physically Based Models in Computer Graphics.” Computer Graphics Forum. Wiley-Blackwell, 2017. https://doi.org/10.1111/cgf.12941.","apa":"Manteaux, P., Wojtan, C., Narain, R., Redon, S., Faure, F., & Cani, M. (2017). Adaptive physically based models in computer graphics. Computer Graphics Forum. Wiley-Blackwell. https://doi.org/10.1111/cgf.12941","ieee":"P. Manteaux, C. Wojtan, R. Narain, S. Redon, F. Faure, and M. Cani, “Adaptive physically based models in computer graphics,” Computer Graphics Forum, vol. 36, no. 6. Wiley-Blackwell, pp. 312–337, 2017."},"oa_version":"Submitted Version","day":"01","date_updated":"2023-09-20T11:05:36Z","date_published":"2017-09-01T00:00:00Z","external_id":{"isi":["000408634200019"]},"language":[{"iso":"eng"}],"month":"09","isi":1,"publisher":"Wiley-Blackwell","author":[{"full_name":"Manteaux, Pierre","last_name":"Manteaux","first_name":"Pierre"},{"id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J","last_name":"Wojtan","orcid":"0000-0001-6646-5546","first_name":"Christopher J"},{"full_name":"Narain, Rahul","last_name":"Narain","first_name":"Rahul"},{"last_name":"Redon","full_name":"Redon, Stéphane","first_name":"Stéphane"},{"last_name":"Faure","full_name":"Faure, François","first_name":"François"},{"full_name":"Cani, Marie","last_name":"Cani","first_name":"Marie"}],"type":"journal_article","scopus_import":"1","volume":36,"has_accepted_license":"1","quality_controlled":"1","article_processing_charge":"No","acknowledgement":"This work was partly supported by the starting grants ADAPT and BigSplash, as well as the advanced grant EXPRESSIVE from the European Research Council (ERC-2012-StG_20111012, ERC-2014-StG_638176 and ERC-2011-ADG_20110209).","ddc":["000"],"publication_identifier":{"issn":["01677055"]},"_id":"1367"},{"language":[{"iso":"eng"}],"conference":{"location":"San Francisco, CA, USA","name":"MIG: Motion in Games","start_date":"2016-10-10","end_date":"2016-10-12"},"date_published":"2016-10-10T00:00:00Z","month":"10","day":"10","date_updated":"2023-02-21T09:49:49Z","article_processing_charge":"No","acknowledgement":"This work was partly supported by the starting grant BigSplash, as well as the advanced grant EXPRESSIVE from the European Research Council (ERC-2014-StG 638176 , and ERC-2011-ADG 20110209).","quality_controlled":"1","_id":"1136","article_number":"2994261","ddc":["004"],"publisher":"ACM","author":[{"full_name":"Manteaux, Pierre","last_name":"Manteaux","first_name":"Pierre"},{"first_name":"Ulysse","full_name":"Vimont, Ulysse","last_name":"Vimont"},{"last_name":"Wojtan","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","first_name":"Christopher J","orcid":"0000-0001-6646-5546"},{"first_name":"Damien","full_name":"Rohmer, Damien","last_name":"Rohmer"},{"first_name":"Marie","full_name":"Cani, Marie","last_name":"Cani"}],"has_accepted_license":"1","scopus_import":"1","type":"conference","publication":"Proceedings of the 9th International Conference on Motion in Games ","department":[{"_id":"ChWo"}],"status":"public","publication_status":"published","year":"2016","publist_id":"6222","citation":{"mla":"Manteaux, Pierre, et al. “Space-Time Sculpting of Liquid Animation.” Proceedings of the 9th International Conference on Motion in Games , 2994261, ACM, 2016, doi:10.1145/2994258.2994261.","short":"P. Manteaux, U. Vimont, C. Wojtan, D. Rohmer, M. Cani, in:, Proceedings of the 9th International Conference on Motion in Games , ACM, 2016.","ama":"Manteaux P, Vimont U, Wojtan C, Rohmer D, Cani M. Space-time sculpting of liquid animation. In: Proceedings of the 9th International Conference on Motion in Games . ACM; 2016. doi:10.1145/2994258.2994261","ieee":"P. Manteaux, U. Vimont, C. Wojtan, D. Rohmer, and M. Cani, “Space-time sculpting of liquid animation,” in Proceedings of the 9th International Conference on Motion in Games , San Francisco, CA, USA, 2016.","apa":"Manteaux, P., Vimont, U., Wojtan, C., Rohmer, D., & Cani, M. (2016). Space-time sculpting of liquid animation. In Proceedings of the 9th International Conference on Motion in Games . San Francisco, CA, USA: ACM. https://doi.org/10.1145/2994258.2994261","ista":"Manteaux P, Vimont U, Wojtan C, Rohmer D, Cani M. 2016. Space-time sculpting of liquid animation. Proceedings of the 9th International Conference on Motion in Games . MIG: Motion in Games, 2994261.","chicago":"Manteaux, Pierre, Ulysse Vimont, Chris Wojtan, Damien Rohmer, and Marie Cani. “Space-Time Sculpting of Liquid Animation.” In Proceedings of the 9th International Conference on Motion in Games . ACM, 2016. https://doi.org/10.1145/2994258.2994261."},"title":"Space-time sculpting of liquid animation","date_created":"2018-12-11T11:50:20Z","ec_funded":1,"main_file_link":[{"url":"https://hal.inria.fr/hal-01367181","open_access":"1"}],"oa_version":"Submitted Version","oa":1,"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","abstract":[{"text":"We propose an interactive sculpting system for seamlessly editing pre-computed animations of liquid, without the need for any resimulation. The input is a sequence of meshes without correspondences representing the liquid surface over time. Our method enables the efficient selection of consistent space-time parts of this animation, such as moving waves or droplets, which we call space-time features. Once selected, a feature can be copied, edited, or duplicated and then pasted back anywhere in space and time in the same or in another liquid animation sequence. Our method circumvents tedious user interactions by automatically computing the spatial and temporal ranges of the selected feature. We also provide space-time shape editing tools for non-uniform scaling, rotation, trajectory changes, and temporal editing to locally speed up or slow down motion. Using our tools, the user can edit and progressively refine any input simulation result, possibly using a library of precomputed space-time features extracted from other animations. In contrast to the trial-and-error loop usually required to edit animation results through the tuning of indirect simulation parameters, our method gives the user full control over the edited space-time behaviors. © 2016 Copyright held by the owner/author(s).","lang":"eng"}],"doi":"10.1145/2994258.2994261","project":[{"_id":"2533E772-B435-11E9-9278-68D0E5697425","call_identifier":"H2020","grant_number":"638176","name":"Efficient Simulation of Natural Phenomena at Extremely Large Scales"}]},{"year":"2016","publist_id":"5879","publication_status":"published","department":[{"_id":"ChWo"}],"status":"public","pubrep_id":"631","intvolume":" 35","issue":"4","project":[{"call_identifier":"H2020","name":"Efficient Simulation of Natural Phenomena at Extremely Large Scales","grant_number":"638176","_id":"2533E772-B435-11E9-9278-68D0E5697425"}],"file":[{"checksum":"140b5532f0a2a006a0149cab7c73c17c","file_id":"4981","access_level":"open_access","file_name":"IST-2016-631-v1+2_a96-bojsen-hansen.pdf","creator":"system","file_size":12422760,"date_created":"2018-12-12T10:13:00Z","relation":"main_file","date_updated":"2020-07-14T12:44:47Z","content_type":"application/pdf"}],"user_id":"4435EBFC-F248-11E8-B48F-1D18A9856A87","abstract":[{"lang":"eng","text":"When aiming to seamlessly integrate a fluid simulation into a larger scenario (like an open ocean), careful attention must be paid to boundary conditions. In particular, one must implement special "non-reflecting" boundary conditions, which dissipate out-going waves as they exit the simulation. Unfortunately, the state of the art in non-reflecting boundary conditions (perfectly-matched layers, or PMLs) only permits trivially simple inflow/outflow conditions, so there is no reliable way to integrate a fluid simulation into a more complicated environment like a stormy ocean or a turbulent river. This paper introduces the first method for combining nonreflecting boundary conditions based on PMLs with inflow/outflow boundary conditions that vary arbitrarily throughout space and time. Our algorithm is a generalization of stateof- the-art mean-flow boundary conditions in the computational fluid dynamics literature, and it allows for seamless integration of a fluid simulation into much more complicated environments. Our method also opens the door for previously-unseen postprocess effects like retroactively changing the location of solid obstacles, and locally increasing the visual detail of a pre-existing simulation."}],"file_date_updated":"2020-07-14T12:44:47Z","acknowledged_ssus":[{"_id":"ScienComp"}],"doi":"10.1145/2897824.2925963","oa":1,"tmp":{"name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","short":"CC BY (4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","image":"/images/cc_by.png"},"oa_version":"Published Version","ec_funded":1,"title":"Generalized non-reflecting boundaries for fluid re-simulation","date_created":"2018-12-11T11:51:35Z","alternative_title":["ACM Transactions on Graphics"],"citation":{"apa":"Bojsen-Hansen, M., & Wojtan, C. (2016). Generalized non-reflecting boundaries for fluid re-simulation (Vol. 35). Presented at the ACM SIGGRAPH, Anaheim, CA, USA: ACM. https://doi.org/10.1145/2897824.2925963","ieee":"M. Bojsen-Hansen and C. Wojtan, “Generalized non-reflecting boundaries for fluid re-simulation,” presented at the ACM SIGGRAPH, Anaheim, CA, USA, 2016, vol. 35, no. 4.","chicago":"Bojsen-Hansen, Morten, and Chris Wojtan. “Generalized Non-Reflecting Boundaries for Fluid Re-Simulation,” Vol. 35. ACM, 2016. https://doi.org/10.1145/2897824.2925963.","ista":"Bojsen-Hansen M, Wojtan C. 2016. Generalized non-reflecting boundaries for fluid re-simulation. ACM SIGGRAPH, ACM Transactions on Graphics, vol. 35, 96.","mla":"Bojsen-Hansen, Morten, and Chris Wojtan. Generalized Non-Reflecting Boundaries for Fluid Re-Simulation. Vol. 35, no. 4, 96, ACM, 2016, doi:10.1145/2897824.2925963.","short":"M. Bojsen-Hansen, C. Wojtan, in:, ACM, 2016.","ama":"Bojsen-Hansen M, Wojtan C. Generalized non-reflecting boundaries for fluid re-simulation. In: Vol 35. ACM; 2016. doi:10.1145/2897824.2925963"},"date_updated":"2023-02-21T10:36:12Z","day":"11","month":"07","date_published":"2016-07-11T00:00:00Z","language":[{"iso":"eng"}],"conference":{"name":"ACM SIGGRAPH","end_date":"2016-07-28","start_date":"2016-07-24","location":"Anaheim, CA, USA"},"type":"conference","volume":35,"has_accepted_license":"1","publisher":"ACM","author":[{"first_name":"Morten","orcid":"0000-0002-4417-3224","last_name":"Bojsen-Hansen","full_name":"Bojsen-Hansen, Morten","id":"439F0C8C-F248-11E8-B48F-1D18A9856A87"},{"orcid":"0000-0001-6646-5546","first_name":"Christopher J","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","last_name":"Wojtan"}],"ddc":["000"],"article_number":"96","_id":"1363","quality_controlled":"1","acknowledgement":"We thank the IST Austria Visual Computing group for helpful feedback throughout the project. "},{"oa_version":"Published Version","ec_funded":1,"title":"Surface only liquids","date_created":"2018-12-11T11:51:35Z","citation":{"chicago":"Da, Fang, David Hahn, Christopher Batty, Chris Wojtan, and Eitan Grinspun. “Surface Only Liquids,” Vol. 35. ACM, 2016. https://doi.org/10.1145/2897824.2925899.","ista":"Da F, Hahn D, Batty C, Wojtan C, Grinspun E. 2016. Surface only liquids. ACM SIGGRAPH, ACM Transactions on Graphics, vol. 35, a78.","ieee":"F. Da, D. Hahn, C. Batty, C. Wojtan, and E. Grinspun, “Surface only liquids,” presented at the ACM SIGGRAPH, Anaheim, CA, USA, 2016, vol. 35, no. 4.","apa":"Da, F., Hahn, D., Batty, C., Wojtan, C., & Grinspun, E. (2016). Surface only liquids (Vol. 35). Presented at the ACM SIGGRAPH, Anaheim, CA, USA: ACM. https://doi.org/10.1145/2897824.2925899","ama":"Da F, Hahn D, Batty C, Wojtan C, Grinspun E. Surface only liquids. In: Vol 35. ACM; 2016. doi:10.1145/2897824.2925899","mla":"Da, Fang, et al. Surface Only Liquids. Vol. 35, no. 4, a78, ACM, 2016, doi:10.1145/2897824.2925899.","short":"F. Da, D. Hahn, C. Batty, C. Wojtan, E. Grinspun, in:, ACM, 2016."},"alternative_title":["ACM Transactions on Graphics"],"file":[{"file_id":"4660","checksum":"6d662893bd447d4f575b4961a2247811","relation":"main_file","date_created":"2018-12-12T10:08:01Z","file_size":10561865,"creator":"system","access_level":"open_access","file_name":"IST-2016-637-v1+1_2016_Da_SOL.pdf","date_updated":"2020-07-14T12:44:46Z","content_type":"application/pdf"}],"project":[{"_id":"2533E772-B435-11E9-9278-68D0E5697425","call_identifier":"H2020","name":"Efficient Simulation of Natural Phenomena at Extremely Large Scales","grant_number":"638176"}],"doi":"10.1145/2897824.2925899","file_date_updated":"2020-07-14T12:44:46Z","abstract":[{"lang":"eng","text":"We propose a novel surface-only technique for simulating incompressible, inviscid and uniform-density liquids with surface tension in three dimensions. The liquid surface is captured by a triangle mesh on which a Lagrangian velocity field is stored. Because advection of the velocity field may violate the incompressibility condition, we devise an orthogonal projection technique to remove the divergence while requiring the evaluation of only two boundary integrals. The forces of surface tension, gravity, and solid contact are all treated by a boundary element solve, allowing us to perform detailed simulations of a wide range of liquid phenomena, including waterbells, droplet and jet collisions, fluid chains, and crown splashes."}],"user_id":"3E5EF7F0-F248-11E8-B48F-1D18A9856A87","oa":1,"pubrep_id":"637","intvolume":" 35","issue":"4","publist_id":"5881","year":"2016","publication_status":"published","status":"public","department":[{"_id":"ChWo"}],"ddc":["000"],"article_number":"a78","_id":"1361","quality_controlled":"1","type":"conference","scopus_import":1,"volume":35,"has_accepted_license":"1","author":[{"first_name":"Fang","last_name":"Da","full_name":"Da, Fang"},{"first_name":"David","last_name":"Hahn","full_name":"Hahn, David","id":"357A6A66-F248-11E8-B48F-1D18A9856A87"},{"first_name":"Christopher","last_name":"Batty","full_name":"Batty, Christopher"},{"last_name":"Wojtan","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J","first_name":"Christopher J","orcid":"0000-0001-6646-5546"},{"last_name":"Grinspun","full_name":"Grinspun, Eitan","first_name":"Eitan"}],"publisher":"ACM","month":"07","date_published":"2016-07-11T00:00:00Z","conference":{"location":"Anaheim, CA, USA","start_date":"2016-07-24","end_date":"2016-07-28","name":"ACM SIGGRAPH"},"language":[{"iso":"eng"}],"date_updated":"2023-02-21T10:36:07Z","day":"11"},{"day":"27","date_updated":"2023-02-21T10:38:30Z","date_published":"2016-05-27T00:00:00Z","language":[{"iso":"eng"}],"month":"05","author":[{"last_name":"Goldade","full_name":"Goldade, Ryan","first_name":"Ryan"},{"first_name":"Christopher","full_name":"Batty, Christopher","last_name":"Batty"},{"last_name":"Wojtan","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","first_name":"Christopher J","orcid":"0000-0001-6646-5546"}],"publisher":"Wiley-Blackwell","scopus_import":1,"type":"journal_article","has_accepted_license":"1","volume":35,"quality_controlled":"1","acknowledgement":"This research was supported by NSERC (RGPIN-04360-2014) and IST Austria. ","ddc":["000"],"_id":"1412","publication_status":"published","department":[{"_id":"ChWo"}],"status":"public","publist_id":"5795","year":"2016","issue":"2","pubrep_id":"612","publication":"Computer Graphics Forum","intvolume":" 35","page":"233 - 242","oa":1,"file":[{"date_created":"2018-12-12T10:13:18Z","file_size":15873858,"relation":"main_file","access_level":"open_access","file_name":"IST-2016-612-v1+2_Wojtan_APracticalMethod_PostPrint_2016.pdf","creator":"system","file_id":"5000","checksum":"8e61387ee2e3bd0e776fbe301629bfd9","content_type":"application/pdf","date_updated":"2020-07-14T12:44:53Z"}],"project":[{"_id":"2533E772-B435-11E9-9278-68D0E5697425","name":"Efficient Simulation of Natural Phenomena at Extremely Large Scales","grant_number":"638176","call_identifier":"H2020"}],"file_date_updated":"2020-07-14T12:44:53Z","doi":"10.1111/cgf.12826","abstract":[{"lang":"eng","text":"Combining high-resolution level set surface tracking with lower resolution physics is an inexpensive method for achieving highly detailed liquid animations. Unfortunately, the inherent resolution mismatch introduces several types of disturbing visual artifacts. We identify the primary sources of these artifacts and present simple, efficient, and practical solutions to address them. First, we propose an unconditionally stable filtering method that selectively removes sub-grid surface artifacts not seen by the fluid physics, while preserving fine detail in dynamic splashing regions. It provides comparable results to recent error-correction techniques at lower cost, without substepping, and with better scaling behavior. Second, we show how a modified narrow-band scheme can ensure accurate free surface boundary conditions in the presence of large resolution mismatches. Our scheme preserves the efficiency of the narrow-band methodology, while eliminating objectionable stairstep artifacts observed in prior work. Third, we demonstrate that the use of linear interpolation of velocity during advection of the high-resolution level set surface is responsible for visible grid-aligned kinks; we therefore advocate higher-order velocity interpolation, and show that it dramatically reduces this artifact. While these three contributions are orthogonal, our results demonstrate that taken together they efficiently address the dominant sources of visual artifacts arising with high-resolution embedded liquid surfaces; the proposed approach offers improved visual quality, a straightforward implementation, and substantially greater scalability than competing methods."}],"user_id":"3E5EF7F0-F248-11E8-B48F-1D18A9856A87","date_created":"2018-12-11T11:51:52Z","title":"A practical method for high-resolution embedded liquid surfaces","citation":{"ista":"Goldade R, Batty C, Wojtan C. 2016. A practical method for high-resolution embedded liquid surfaces. Computer Graphics Forum. 35(2), 233–242.","chicago":"Goldade, Ryan, Christopher Batty, and Chris Wojtan. “A Practical Method for High-Resolution Embedded Liquid Surfaces.” Computer Graphics Forum. Wiley-Blackwell, 2016. https://doi.org/10.1111/cgf.12826.","ieee":"R. Goldade, C. Batty, and C. Wojtan, “A practical method for high-resolution embedded liquid surfaces,” Computer Graphics Forum, vol. 35, no. 2. Wiley-Blackwell, pp. 233–242, 2016.","apa":"Goldade, R., Batty, C., & Wojtan, C. (2016). A practical method for high-resolution embedded liquid surfaces. Computer Graphics Forum. Wiley-Blackwell. https://doi.org/10.1111/cgf.12826","ama":"Goldade R, Batty C, Wojtan C. A practical method for high-resolution embedded liquid surfaces. Computer Graphics Forum. 2016;35(2):233-242. doi:10.1111/cgf.12826","short":"R. Goldade, C. Batty, C. Wojtan, Computer Graphics Forum 35 (2016) 233–242.","mla":"Goldade, Ryan, et al. “A Practical Method for High-Resolution Embedded Liquid Surfaces.” Computer Graphics Forum, vol. 35, no. 2, Wiley-Blackwell, 2016, pp. 233–42, doi:10.1111/cgf.12826."},"oa_version":"Submitted Version","ec_funded":1},{"quality_controlled":"1","ddc":["000"],"_id":"1415","publisher":"Wiley-Blackwell","author":[{"first_name":"Florian","last_name":"Ferstl","full_name":"Ferstl, Florian"},{"full_name":"Ando, Ryoichi","last_name":"Ando","first_name":"Ryoichi"},{"last_name":"Wojtan","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","first_name":"Christopher J","orcid":"0000-0001-6646-5546"},{"full_name":"Westermann, Rüdiger","last_name":"Westermann","first_name":"Rüdiger"},{"first_name":"Nils","full_name":"Thuerey, Nils","last_name":"Thuerey"}],"type":"journal_article","scopus_import":1,"volume":35,"has_accepted_license":"1","date_published":"2016-05-01T00:00:00Z","language":[{"iso":"eng"}],"month":"05","day":"01","date_updated":"2023-02-21T10:38:38Z","title":"Narrow band FLIP for liquid simulations","date_created":"2018-12-11T11:51:53Z","citation":{"ama":"Ferstl F, Ando R, Wojtan C, Westermann R, Thuerey N. Narrow band FLIP for liquid simulations. Computer Graphics Forum. 2016;35(2):225-232. doi:10.1111/cgf.12825","short":"F. Ferstl, R. Ando, C. Wojtan, R. Westermann, N. Thuerey, Computer Graphics Forum 35 (2016) 225–232.","mla":"Ferstl, Florian, et al. “Narrow Band FLIP for Liquid Simulations.” Computer Graphics Forum, vol. 35, no. 2, Wiley-Blackwell, 2016, pp. 225–32, doi:10.1111/cgf.12825.","ista":"Ferstl F, Ando R, Wojtan C, Westermann R, Thuerey N. 2016. Narrow band FLIP for liquid simulations. Computer Graphics Forum. 35(2), 225–232.","chicago":"Ferstl, Florian, Ryoichi Ando, Chris Wojtan, Rüdiger Westermann, and Nils Thuerey. “Narrow Band FLIP for Liquid Simulations.” Computer Graphics Forum. Wiley-Blackwell, 2016. https://doi.org/10.1111/cgf.12825.","ieee":"F. Ferstl, R. Ando, C. Wojtan, R. Westermann, and N. Thuerey, “Narrow band FLIP for liquid simulations,” Computer Graphics Forum, vol. 35, no. 2. Wiley-Blackwell, pp. 225–232, 2016.","apa":"Ferstl, F., Ando, R., Wojtan, C., Westermann, R., & Thuerey, N. (2016). Narrow band FLIP for liquid simulations. Computer Graphics Forum. Wiley-Blackwell. https://doi.org/10.1111/cgf.12825"},"oa_version":"Submitted Version","page":"225 - 232","oa":1,"file":[{"content_type":"application/pdf","date_updated":"2020-07-14T12:44:53Z","relation":"main_file","date_created":"2018-12-12T10:12:22Z","file_size":5938324,"creator":"system","access_level":"open_access","file_name":"IST-2016-611-v1+3_CW_nbflip_postprint_2016.pdf","file_id":"4940","checksum":"984afbe510ed48019025dff1dcc7baad"}],"user_id":"3E5EF7F0-F248-11E8-B48F-1D18A9856A87","abstract":[{"text":"The Fluid Implicit Particle method (FLIP) for liquid simulations uses particles to reduce numerical dissipation and provide important visual cues for events like complex splashes and small-scale features near the liquid surface. Unfortunately, FLIP simulations can be computationally expensive, because they require a dense sampling of particles to fill the entire liquid volume. Furthermore, the vast majority of these FLIP particles contribute nothing to the fluid's visual appearance, especially for larger volumes of liquid. We present a method that only uses FLIP particles within a narrow band of the liquid surface, while efficiently representing the remaining inner volume on a regular grid. We show that a naïve realization of this idea introduces unstable and uncontrollable energy fluctuations, and we propose a novel coupling scheme between FLIP particles and regular grid which overcomes this problem. Our method drastically reduces the particle count and simulation times while yielding results that are nearly indistinguishable from regular FLIP simulations. Our approach is easy to integrate into any existing FLIP implementation.","lang":"eng"}],"doi":"10.1111/cgf.12825","file_date_updated":"2020-07-14T12:44:53Z","issue":"2","publication":"Computer Graphics Forum","pubrep_id":"611","intvolume":" 35","publication_status":"published","department":[{"_id":"ChWo"}],"status":"public","year":"2016","publist_id":"5793"},{"publication_status":"published","department":[{"_id":"ChWo"}],"status":"public","year":"2016","publist_id":"5880","issue":"4","pubrep_id":"632","intvolume":" 35","oa":1,"file":[{"file_size":12453704,"date_created":"2018-12-12T10:15:04Z","relation":"main_file","access_level":"open_access","file_name":"IST-2016-632-v1+2_a104-hahn.pdf","creator":"system","file_id":"5121","checksum":"943712d9c9dc8bb5048d4adc561d7d38","content_type":"application/pdf","date_updated":"2020-07-14T12:44:46Z"}],"project":[{"name":"Efficient Simulation of Natural Phenomena at Extremely Large Scales","grant_number":"638176","call_identifier":"H2020","_id":"2533E772-B435-11E9-9278-68D0E5697425"}],"user_id":"3E5EF7F0-F248-11E8-B48F-1D18A9856A87","abstract":[{"text":"We present a boundary element based method for fast simulation of brittle fracture. By introducing simplifying assumptions that allow us to quickly estimate stress intensities and opening displacements during crack propagation, we build a fracture algorithm where the cost of each time step scales linearly with the length of the crackfront. The transition from a full boundary element method to our faster variant is possible at the beginning of any time step. This allows us to build a hybrid method, which uses the expensive but more accurate BEM while the number of degrees of freedom is low, and uses the fast method once that number exceeds a given threshold as the crack geometry becomes more complicated. Furthermore, we integrate this fracture simulation with a standard rigid-body solver. Our rigid-body coupling solves a Neumann boundary value problem by carefully separating translational, rotational and deformational components of the collision forces and then applying a Tikhonov regularizer to the resulting linear system. We show that our method produces physically reasonable results in standard test cases and is capable of dealing with complex scenes faster than previous finite- or boundary element approaches.","lang":"eng"}],"file_date_updated":"2020-07-14T12:44:46Z","doi":"10.1145/2897824.2925902","title":"Fast approximations for boundary element based brittle fracture simulation","date_created":"2018-12-11T11:51:35Z","alternative_title":["ACM Transactions on Graphics"],"citation":{"chicago":"Hahn, David, and Chris Wojtan. “Fast Approximations for Boundary Element Based Brittle Fracture Simulation,” Vol. 35. ACM, 2016. https://doi.org/10.1145/2897824.2925902.","ista":"Hahn D, Wojtan C. 2016. Fast approximations for boundary element based brittle fracture simulation. ACM SIGGRAPH, ACM Transactions on Graphics, vol. 35, 104.","ieee":"D. Hahn and C. Wojtan, “Fast approximations for boundary element based brittle fracture simulation,” presented at the ACM SIGGRAPH, Anaheim, CA, USA, 2016, vol. 35, no. 4.","apa":"Hahn, D., & Wojtan, C. (2016). Fast approximations for boundary element based brittle fracture simulation (Vol. 35). Presented at the ACM SIGGRAPH, Anaheim, CA, USA: ACM. https://doi.org/10.1145/2897824.2925902","ama":"Hahn D, Wojtan C. Fast approximations for boundary element based brittle fracture simulation. In: Vol 35. ACM; 2016. doi:10.1145/2897824.2925902","mla":"Hahn, David, and Chris Wojtan. Fast Approximations for Boundary Element Based Brittle Fracture Simulation. Vol. 35, no. 4, 104, ACM, 2016, doi:10.1145/2897824.2925902.","short":"D. Hahn, C. Wojtan, in:, ACM, 2016."},"tmp":{"name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","short":"CC BY (4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","image":"/images/cc_by.png"},"oa_version":"Published Version","ec_funded":1,"related_material":{"record":[{"id":"839","status":"public","relation":"dissertation_contains"}]},"day":"01","date_updated":"2023-09-07T12:02:56Z","date_published":"2016-07-01T00:00:00Z","conference":{"location":"Anaheim, CA, USA","name":"ACM SIGGRAPH","start_date":"2016-07-24","end_date":"2016-07-28"},"language":[{"iso":"eng"}],"month":"07","publisher":"ACM","author":[{"first_name":"David","last_name":"Hahn","id":"357A6A66-F248-11E8-B48F-1D18A9856A87","full_name":"Hahn, David"},{"id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J","last_name":"Wojtan","orcid":"0000-0001-6646-5546","first_name":"Christopher J"}],"type":"conference","has_accepted_license":"1","volume":35,"quality_controlled":"1","ddc":["000"],"article_number":"104","_id":"1362"},{"_id":"1634","article_number":"149","ddc":["000"],"quality_controlled":"1","volume":34,"has_accepted_license":"1","scopus_import":1,"type":"conference","author":[{"full_name":"Da, Fang","last_name":"Da","first_name":"Fang"},{"last_name":"Batty","full_name":"Batty, Christopher","first_name":"Christopher"},{"last_name":"Wojtan","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J","first_name":"Christopher J","orcid":"0000-0001-6646-5546"},{"first_name":"Eitan","full_name":"Grinspun, Eitan","last_name":"Grinspun"}],"publisher":"ACM","month":"07","conference":{"location":"Los Angeles, CA, United States","end_date":"2015-08-13","start_date":"2015-08-09","name":"SIGGRAPH: Special Interest Group on Computer Graphics and Interactive Techniques"},"language":[{"iso":"eng"}],"date_published":"2015-07-27T00:00:00Z","date_updated":"2023-02-23T10:07:42Z","day":"27","ec_funded":1,"oa_version":"Submitted Version","citation":{"chicago":"Da, Fang, Christopher Batty, Chris Wojtan, and Eitan Grinspun. “Double Bubbles sans Toil and Trouble: Discrete Circulation-Preserving Vortex Sheets for Soap Films and Foams,” Vol. 34. ACM, 2015. https://doi.org/10.1145/2767003.","ista":"Da F, Batty C, Wojtan C, Grinspun E. 2015. Double bubbles sans toil and trouble: discrete circulation-preserving vortex sheets for soap films and foams. SIGGRAPH: Special Interest Group on Computer Graphics and Interactive Techniques vol. 34, 149.","ieee":"F. Da, C. Batty, C. Wojtan, and E. Grinspun, “Double bubbles sans toil and trouble: discrete circulation-preserving vortex sheets for soap films and foams,” presented at the SIGGRAPH: Special Interest Group on Computer Graphics and Interactive Techniques, Los Angeles, CA, United States, 2015, vol. 34, no. 4.","apa":"Da, F., Batty, C., Wojtan, C., & Grinspun, E. (2015). Double bubbles sans toil and trouble: discrete circulation-preserving vortex sheets for soap films and foams (Vol. 34). Presented at the SIGGRAPH: Special Interest Group on Computer Graphics and Interactive Techniques, Los Angeles, CA, United States: ACM. https://doi.org/10.1145/2767003","ama":"Da F, Batty C, Wojtan C, Grinspun E. Double bubbles sans toil and trouble: discrete circulation-preserving vortex sheets for soap films and foams. In: Vol 34. ACM; 2015. doi:10.1145/2767003","mla":"Da, Fang, et al. Double Bubbles sans Toil and Trouble: Discrete Circulation-Preserving Vortex Sheets for Soap Films and Foams. Vol. 34, no. 4, 149, ACM, 2015, doi:10.1145/2767003.","short":"F. Da, C. Batty, C. Wojtan, E. Grinspun, in:, ACM, 2015."},"date_created":"2018-12-11T11:53:09Z","title":"Double bubbles sans toil and trouble: discrete circulation-preserving vortex sheets for soap films and foams","file_date_updated":"2020-07-14T12:45:07Z","doi":"10.1145/2767003","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","abstract":[{"text":"Simulating the delightful dynamics of soap films, bubbles, and foams has traditionally required the use of a fully three-dimensional many-phase Navier-Stokes solver, even though their visual appearance is completely dominated by the thin liquid surface. We depart from earlier work on soap bubbles and foams by noting that their dynamics are naturally described by a Lagrangian vortex sheet model in which circulation is the primary variable. This leads us to derive a novel circulation-preserving surface-only discretization of foam dynamics driven by surface tension on a non-manifold triangle mesh. We represent the surface using a mesh-based multimaterial surface tracker which supports complex bubble topology changes, and evolve the surface according to the ambient air flow induced by a scalar circulation field stored on the mesh. Surface tension forces give rise to a simple update rule for circulation, even at non-manifold Plateau borders, based on a discrete measure of signed scalar mean curvature. We further incorporate vertex constraints to enable the interaction of soap films with wires. The result is a method that is at once simple, robust, and efficient, yet able to capture an array of soap films behaviors including foam rearrangement, catenoid collapse, blowing bubbles, and double bubbles being pulled apart.","lang":"eng"}],"project":[{"_id":"2533E772-B435-11E9-9278-68D0E5697425","call_identifier":"H2020","name":"Efficient Simulation of Natural Phenomena at Extremely Large Scales","grant_number":"638176"}],"file":[{"content_type":"application/pdf","date_updated":"2020-07-14T12:45:07Z","access_level":"open_access","file_name":"IST-2016-608-v1+1_doublebubbles.pdf","creator":"system","date_created":"2018-12-12T10:11:14Z","file_size":8973215,"relation":"main_file","checksum":"57b07d78d2d612a8052744b37d4a71fa","file_id":"4867"}],"oa":1,"intvolume":" 34","pubrep_id":"608","issue":"4","publist_id":"5521","year":"2015","status":"public","department":[{"_id":"ChWo"}],"publication_status":"published"},{"quality_controlled":"1","acknowledgement":"The first author was supported by a JSPS Postdoctoral Fellowship for Research Abroad. This work was also supported by the ERC projects ERC-2014-StG-637014 realFlow and ERC-2014- StG-638176 BigSplash.","ddc":["000"],"article_number":"53","_id":"1632","author":[{"full_name":"Ando, Ryoichi","last_name":"Ando","first_name":"Ryoichi"},{"first_name":"Nils","last_name":"Thuerey","full_name":"Thuerey, Nils"},{"first_name":"Christopher J","orcid":"0000-0001-6646-5546","last_name":"Wojtan","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J"}],"publisher":"ACM","scopus_import":1,"type":"conference","has_accepted_license":"1","volume":34,"date_published":"2015-07-27T00:00:00Z","language":[{"iso":"eng"}],"conference":{"location":"Los Angeles, CA, USA","name":"SIGGRAPH: Special Interest Group on Computer Graphics and Interactive Techniques","end_date":"2015-08-13","start_date":"2015-08-09"},"month":"07","day":"27","date_updated":"2023-02-23T10:07:37Z","title":"A stream function solver for liquid simulations","date_created":"2018-12-11T11:53:09Z","citation":{"mla":"Ando, Ryoichi, et al. A Stream Function Solver for Liquid Simulations. Vol. 34, no. 4, 53, ACM, 2015, doi:10.1145/2766935.","short":"R. Ando, N. Thuerey, C. Wojtan, in:, ACM, 2015.","ama":"Ando R, Thuerey N, Wojtan C. A stream function solver for liquid simulations. In: Vol 34. ACM; 2015. doi:10.1145/2766935","apa":"Ando, R., Thuerey, N., & Wojtan, C. (2015). A stream function solver for liquid simulations (Vol. 34). Presented at the SIGGRAPH: Special Interest Group on Computer Graphics and Interactive Techniques, Los Angeles, CA, USA: ACM. https://doi.org/10.1145/2766935","ieee":"R. Ando, N. Thuerey, and C. Wojtan, “A stream function solver for liquid simulations,” presented at the SIGGRAPH: Special Interest Group on Computer Graphics and Interactive Techniques, Los Angeles, CA, USA, 2015, vol. 34, no. 4.","ista":"Ando R, Thuerey N, Wojtan C. 2015. A stream function solver for liquid simulations. SIGGRAPH: Special Interest Group on Computer Graphics and Interactive Techniques, ACM Transactions on Graphics, vol. 34, 53.","chicago":"Ando, Ryoichi, Nils Thuerey, and Chris Wojtan. “A Stream Function Solver for Liquid Simulations,” Vol. 34. ACM, 2015. https://doi.org/10.1145/2766935."},"alternative_title":["ACM Transactions on Graphics"],"oa_version":"Submitted Version","oa":1,"file":[{"checksum":"7a9afdfaba9209157ce19376e15bc90b","file_id":"4909","access_level":"open_access","file_name":"IST-2016-610-v1+1_vecpotential.pdf","creator":"system","file_size":21831121,"date_created":"2018-12-12T10:11:52Z","relation":"main_file","date_updated":"2020-07-14T12:45:07Z","content_type":"application/pdf"}],"doi":"10.1145/2766935","file_date_updated":"2020-07-14T12:45:07Z","abstract":[{"lang":"eng","text":"This paper presents a liquid simulation technique that enforces the incompressibility condition using a stream function solve instead of a pressure projection. Previous methods have used stream function techniques for the simulation of detailed single-phase flows, but a formulation for liquid simulation has proved elusive in part due to the free surface boundary conditions. In this paper, we introduce a stream function approach to liquid simulations with novel boundary conditions for free surfaces, solid obstacles, and solid-fluid coupling.\r\n\r\nAlthough our approach increases the dimension of the linear system necessary to enforce incompressibility, it provides interesting and surprising benefits. First, the resulting flow is guaranteed to be divergence-free regardless of the accuracy of the solve. Second, our free-surface boundary conditions guarantee divergence-free motion even in the un-simulated air phase, which enables two-phase flow simulation by only computing a single phase. We implemented this method using a variant of FLIP simulation which only samples particles within a narrow band of the liquid surface, and we illustrate the effectiveness of our method for detailed two-phase flow simulations with complex boundaries, detailed bubble interactions, and two-way solid-fluid coupling."}],"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","issue":"4","pubrep_id":"610","intvolume":" 34","publication_status":"published","status":"public","department":[{"_id":"ChWo"}],"publist_id":"5523","year":"2015"},{"quality_controlled":"1","acknowledgement":"The first author was supported by a JSPS Postdoctoral Fellowship for Research Abroad","ddc":["000"],"_id":"1735","author":[{"last_name":"Ando","full_name":"Ando, Ryoichi","first_name":"Ryoichi"},{"first_name":"Nils","last_name":"Thürey","full_name":"Thürey, Nils"},{"id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J","last_name":"Wojtan","orcid":"0000-0001-6646-5546","first_name":"Christopher J"}],"publisher":"Wiley","type":"journal_article","scopus_import":1,"has_accepted_license":"1","volume":34,"date_published":"2015-05-01T00:00:00Z","language":[{"iso":"eng"}],"month":"05","day":"01","date_updated":"2023-02-23T10:12:11Z","date_created":"2018-12-11T11:53:44Z","title":"A dimension-reduced pressure solver for liquid simulations","citation":{"ista":"Ando R, Thürey N, Wojtan C. 2015. A dimension-reduced pressure solver for liquid simulations. Computer Graphics Forum. 34(2), 473–480.","chicago":"Ando, Ryoichi, Nils Thürey, and Chris Wojtan. “A Dimension-Reduced Pressure Solver for Liquid Simulations.” Computer Graphics Forum. Wiley, 2015. https://doi.org/10.1111/cgf.12576.","apa":"Ando, R., Thürey, N., & Wojtan, C. (2015). A dimension-reduced pressure solver for liquid simulations. Computer Graphics Forum. Wiley. https://doi.org/10.1111/cgf.12576","ieee":"R. Ando, N. Thürey, and C. Wojtan, “A dimension-reduced pressure solver for liquid simulations,” Computer Graphics Forum, vol. 34, no. 2. Wiley, pp. 473–480, 2015.","ama":"Ando R, Thürey N, Wojtan C. A dimension-reduced pressure solver for liquid simulations. Computer Graphics Forum. 2015;34(2):473-480. doi:10.1111/cgf.12576","mla":"Ando, Ryoichi, et al. “A Dimension-Reduced Pressure Solver for Liquid Simulations.” Computer Graphics Forum, vol. 34, no. 2, Wiley, 2015, pp. 473–80, doi:10.1111/cgf.12576.","short":"R. Ando, N. Thürey, C. Wojtan, Computer Graphics Forum 34 (2015) 473–480."},"oa_version":"Submitted Version","page":"473 - 480","oa":1,"file":[{"access_level":"open_access","file_name":"IST-2016-607-v1+1_coarsegrid.pdf","creator":"system","file_size":6312352,"date_created":"2018-12-12T10:16:30Z","relation":"main_file","checksum":"590752bf977855b337a80f78a9bc2404","file_id":"5218","content_type":"application/pdf","date_updated":"2020-07-14T12:45:15Z"}],"file_date_updated":"2020-07-14T12:45:15Z","doi":"10.1111/cgf.12576","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","abstract":[{"lang":"eng","text":"This work presents a method for efficiently simplifying the pressure projection step in a liquid simulation. We first devise a straightforward dimension reduction technique that dramatically reduces the cost of solving the pressure projection. Next, we introduce a novel change of basis that satisfies free-surface boundary conditions exactly, regardless of the accuracy of the pressure solve. When combined, these ideas greatly reduce the computational complexity of the pressure solve without compromising free surface boundary conditions at the highest level of detail. Our techniques are easy to parallelize, and they effectively eliminate the computational bottleneck for large liquid simulations."}],"issue":"2","pubrep_id":"607","publication":"Computer Graphics Forum","intvolume":" 34","publication_status":"published","department":[{"_id":"ChWo"}],"status":"public","publist_id":"5389","year":"2015"},{"department":[{"_id":"ChWo"}],"status":"public","publication_status":"published","publist_id":"5292","year":"2015","issue":"3","intvolume":" 34","pubrep_id":"575","publication":"ACM Transactions on Graphics","oa":1,"file_date_updated":"2020-07-14T12:45:17Z","doi":"10.1145/2714572","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","abstract":[{"lang":"eng","text":"We present an efficient wavefront tracking algorithm for animating bodies of water that interact with their environment. Our contributions include: a novel wavefront tracking technique that enables dispersion, refraction, reflection, and diffraction in the same simulation; a unique multivalued function interpolation method that enables our simulations to elegantly sidestep the Nyquist limit; a dispersion approximation for efficiently amplifying the number of simulated waves by several orders of magnitude; and additional extensions that allow for time-dependent effects and interactive artistic editing of the resulting animation. Our contributions combine to give us multitudes more wave details than similar algorithms, while maintaining high frame rates and allowing close camera zooms."}],"file":[{"date_updated":"2020-07-14T12:45:17Z","content_type":"application/pdf","file_id":"4933","checksum":"67c9f4fa370def68cdf31299e48bc91f","relation":"main_file","file_size":23712153,"date_created":"2018-12-12T10:12:15Z","creator":"system","file_name":"IST-2016-575-v1+1_wavefront_preprint.pdf","access_level":"open_access"}],"project":[{"_id":"25357BD2-B435-11E9-9278-68D0E5697425","grant_number":"P 24352-N23","name":"Deep Pictures: Creating Visual and Haptic Vector Images","call_identifier":"FWF"},{"_id":"2533E772-B435-11E9-9278-68D0E5697425","name":"Efficient Simulation of Natural Phenomena at Extremely Large Scales","grant_number":"638176","call_identifier":"H2020"}],"citation":{"mla":"Jeschke, Stefan, and Chris Wojtan. “Water Wave Animation via Wavefront Parameter Interpolation.” ACM Transactions on Graphics, vol. 34, no. 3, 27, ACM, 2015, doi:10.1145/2714572.","short":"S. Jeschke, C. Wojtan, ACM Transactions on Graphics 34 (2015).","ama":"Jeschke S, Wojtan C. Water wave animation via wavefront parameter interpolation. ACM Transactions on Graphics. 2015;34(3). doi:10.1145/2714572","ieee":"S. Jeschke and C. Wojtan, “Water wave animation via wavefront parameter interpolation,” ACM Transactions on Graphics, vol. 34, no. 3. ACM, 2015.","apa":"Jeschke, S., & Wojtan, C. (2015). Water wave animation via wavefront parameter interpolation. ACM Transactions on Graphics. ACM. https://doi.org/10.1145/2714572","chicago":"Jeschke, Stefan, and Chris Wojtan. “Water Wave Animation via Wavefront Parameter Interpolation.” ACM Transactions on Graphics. ACM, 2015. https://doi.org/10.1145/2714572.","ista":"Jeschke S, Wojtan C. 2015. Water wave animation via wavefront parameter interpolation. ACM Transactions on Graphics. 34(3), 27."},"date_created":"2018-12-11T11:54:09Z","title":"Water wave animation via wavefront parameter interpolation","ec_funded":1,"oa_version":"Submitted Version","day":"01","date_updated":"2023-02-23T10:15:40Z","language":[{"iso":"eng"}],"date_published":"2015-04-01T00:00:00Z","month":"04","author":[{"id":"44D6411A-F248-11E8-B48F-1D18A9856A87","full_name":"Jeschke, Stefan","last_name":"Jeschke","first_name":"Stefan"},{"first_name":"Christopher J","orcid":"0000-0001-6646-5546","last_name":"Wojtan","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J"}],"publisher":"ACM","volume":34,"has_accepted_license":"1","scopus_import":1,"type":"journal_article","quality_controlled":"1","_id":"1814","article_number":"27","ddc":["000"]},{"date_updated":"2023-09-07T12:02:56Z","day":"27","month":"07","language":[{"iso":"eng"}],"conference":{"location":"Los Angeles, CA, United States","end_date":"2015-08-13","start_date":"2015-08-09","name":"SIGGRAPH: Special Interest Group on Computer Graphics and Interactive Techniques"},"date_published":"2015-07-27T00:00:00Z","volume":34,"has_accepted_license":"1","type":"conference","scopus_import":1,"publisher":"ACM","author":[{"last_name":"Hahn","full_name":"Hahn, David","id":"357A6A66-F248-11E8-B48F-1D18A9856A87","first_name":"David"},{"id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J","last_name":"Wojtan","orcid":"0000-0001-6646-5546","first_name":"Christopher J"}],"_id":"1633","article_number":"151","ddc":["000"],"quality_controlled":"1","year":"2015","publist_id":"5522","status":"public","department":[{"_id":"ChWo"}],"publication_status":"published","intvolume":" 34","pubrep_id":"609","issue":"4","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","abstract":[{"lang":"eng","text":"We present a method for simulating brittle fracture under the assumptions of quasi-static linear elastic fracture mechanics (LEFM). Using the boundary element method (BEM) and Lagrangian crack-fronts, we produce highly detailed fracture surfaces. The computational cost of the BEM is alleviated by using a low-resolution mesh and interpolating the resulting stress intensity factors when propagating the high-resolution crack-front.\r\n\r\nOur system produces physics-based fracture surfaces with high spatial and temporal resolution, taking spatial variation of material toughness and/or strength into account. It also allows for crack initiation to be handled separately from crack propagation, which is not only more reasonable from a physics perspective, but can also be used to control the simulation.\r\n\r\nSeparating the resolution of the crack-front from the resolution of the computational mesh increases the efficiency and therefore the amount of visual detail on the resulting fracture surfaces. The BEM also allows us to re-use previously computed blocks of the system matrix."}],"doi":"10.1145/2766896","file_date_updated":"2020-07-14T12:45:07Z","file":[{"date_updated":"2020-07-14T12:45:07Z","content_type":"application/pdf","checksum":"955aee971983f6b6152bcc1c9b4a7c20","file_id":"5131","file_name":"IST-2016-609-v1+1_FractureBEM.pdf","access_level":"open_access","creator":"system","file_size":20154270,"date_created":"2018-12-12T10:15:13Z","relation":"main_file"}],"project":[{"_id":"2533E772-B435-11E9-9278-68D0E5697425","grant_number":"638176","name":"Efficient Simulation of Natural Phenomena at Extremely Large Scales","call_identifier":"H2020"}],"oa":1,"ec_funded":1,"related_material":{"record":[{"relation":"dissertation_contains","status":"public","id":"839"}]},"oa_version":"Submitted Version","citation":{"mla":"Hahn, David, and Chris Wojtan. High-Resolution Brittle Fracture Simulation with Boundary Elements. Vol. 34, no. 4, 151, ACM, 2015, doi:10.1145/2766896.","short":"D. Hahn, C. Wojtan, in:, ACM, 2015.","ama":"Hahn D, Wojtan C. High-resolution brittle fracture simulation with boundary elements. In: Vol 34. ACM; 2015. doi:10.1145/2766896","apa":"Hahn, D., & Wojtan, C. (2015). High-resolution brittle fracture simulation with boundary elements (Vol. 34). Presented at the SIGGRAPH: Special Interest Group on Computer Graphics and Interactive Techniques, Los Angeles, CA, United States: ACM. https://doi.org/10.1145/2766896","ieee":"D. Hahn and C. Wojtan, “High-resolution brittle fracture simulation with boundary elements,” presented at the SIGGRAPH: Special Interest Group on Computer Graphics and Interactive Techniques, Los Angeles, CA, United States, 2015, vol. 34, no. 4.","ista":"Hahn D, Wojtan C. 2015. High-resolution brittle fracture simulation with boundary elements. SIGGRAPH: Special Interest Group on Computer Graphics and Interactive Techniques vol. 34, 151.","chicago":"Hahn, David, and Chris Wojtan. “High-Resolution Brittle Fracture Simulation with Boundary Elements,” Vol. 34. ACM, 2015. https://doi.org/10.1145/2766896."},"date_created":"2018-12-11T11:53:09Z","title":"High-resolution brittle fracture simulation with boundary elements"},{"date_published":"2014-07-01T00:00:00Z","conference":{"start_date":"2014-08-10","end_date":"2014-08-14","name":"SIGGRAPH: International Conference and Exhibition on Computer Graphics and Interactive Techniques","location":"Vancouver, Canada"},"language":[{"iso":"eng"}],"month":"07","day":"01","date_updated":"2022-08-25T14:02:46Z","quality_controlled":"1","article_processing_charge":"No","article_number":"137","ddc":["000"],"_id":"2058","publisher":"ACM","author":[{"last_name":"Raveendran","full_name":"Raveendran, Karthik","first_name":"Karthik"},{"last_name":"Wojtan","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","first_name":"Christopher J","orcid":"0000-0001-6646-5546"},{"full_name":"Thuerey, Nils","last_name":"Thuerey","first_name":"Nils"},{"first_name":"Greg","last_name":"Türk","full_name":"Türk, Greg"}],"type":"conference","scopus_import":"1","volume":33,"has_accepted_license":"1","issue":"4","publication":"ACM Transactions on Graphics","pubrep_id":"606","intvolume":" 33","publication_status":"published","department":[{"_id":"ChWo"}],"status":"public","year":"2014","publist_id":"4988","title":"Blending liquids","date_created":"2018-12-11T11:55:28Z","citation":{"ama":"Raveendran K, Wojtan C, Thuerey N, Türk G. Blending liquids. In: ACM Transactions on Graphics. Vol 33. ACM; 2014. doi:10.1145/2601097.2601126","mla":"Raveendran, Karthik, et al. “Blending Liquids.” ACM Transactions on Graphics, vol. 33, no. 4, 137, ACM, 2014, doi:10.1145/2601097.2601126.","short":"K. Raveendran, C. Wojtan, N. Thuerey, G. Türk, in:, ACM Transactions on Graphics, ACM, 2014.","chicago":"Raveendran, Karthik, Chris Wojtan, Nils Thuerey, and Greg Türk. “Blending Liquids.” In ACM Transactions on Graphics, Vol. 33. ACM, 2014. https://doi.org/10.1145/2601097.2601126.","ista":"Raveendran K, Wojtan C, Thuerey N, Türk G. 2014. Blending liquids. ACM Transactions on Graphics. SIGGRAPH: International Conference and Exhibition on Computer Graphics and Interactive Techniques vol. 33, 137.","apa":"Raveendran, K., Wojtan, C., Thuerey, N., & Türk, G. (2014). Blending liquids. In ACM Transactions on Graphics (Vol. 33). Vancouver, Canada: ACM. https://doi.org/10.1145/2601097.2601126","ieee":"K. Raveendran, C. Wojtan, N. Thuerey, and G. Türk, “Blending liquids,” in ACM Transactions on Graphics, Vancouver, Canada, 2014, vol. 33, no. 4."},"oa_version":"Submitted Version","oa":1,"project":[{"grant_number":"11-NSF-1070","name":"ROOTS Genome-wide Analysis of Root Traits","_id":"25636330-B435-11E9-9278-68D0E5697425"}],"file":[{"date_updated":"2020-07-14T12:45:27Z","content_type":"application/pdf","file_id":"4688","checksum":"1752760a2e71e254537f31c0d10d9c6c","file_size":8387384,"date_created":"2018-12-12T10:08:27Z","relation":"main_file","access_level":"open_access","file_name":"IST-2016-606-v1+1_BlendingLiquids-Preprint.pdf","creator":"system"}],"user_id":"3E5EF7F0-F248-11E8-B48F-1D18A9856A87","abstract":[{"text":"We present a method for smoothly blending between existing liquid animations. We introduce a semi-automatic method for matching two existing liquid animations, which we use to create new fluid motion that plausibly interpolates the input. Our contributions include a new space-time non-rigid iterative closest point algorithm that incorporates user guidance, a subsampling technique for efficient registration of meshes with millions of vertices, and a fast surface extraction algorithm that produces 3D triangle meshes from a 4D space-time surface. Our technique can be used to instantly create hundreds of new simulations, or to interactively explore complex parameter spaces. Our method is guaranteed to produce output that does not deviate from the input animations, and it generalizes to multiple dimensions. Because our method runs at interactive rates after the initial precomputation step, it has potential applications in games and training simulations.","lang":"eng"}],"doi":"10.1145/2601097.2601126","file_date_updated":"2020-07-14T12:45:27Z"},{"date_published":"2013-07-01T00:00:00Z","language":[{"iso":"eng"}],"month":"07","day":"01","date_updated":"2023-02-23T10:44:14Z","quality_controlled":"1","article_number":"103","ddc":["000"],"_id":"2466","publisher":"ACM","author":[{"first_name":"Ryoichi","full_name":"Ando, Ryoichi","last_name":"Ando"},{"full_name":"Thuerey, Nils","last_name":"Thuerey","first_name":"Nils"},{"full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","last_name":"Wojtan","orcid":"0000-0001-6646-5546","first_name":"Christopher J"}],"type":"journal_article","scopus_import":1,"volume":32,"has_accepted_license":"1","issue":"4","publication":"ACM Transactions on Graphics","pubrep_id":"605","intvolume":" 32","publication_status":"published","status":"public","department":[{"_id":"ChWo"}],"year":"2013","publist_id":"4436","date_created":"2018-12-11T11:57:50Z","title":"Highly adaptive liquid simulations on tetrahedral meshes","citation":{"short":"R. Ando, N. Thuerey, C. Wojtan, ACM Transactions on Graphics 32 (2013).","mla":"Ando, Ryoichi, et al. “Highly Adaptive Liquid Simulations on Tetrahedral Meshes.” ACM Transactions on Graphics, vol. 32, no. 4, 103, ACM, 2013, doi:10.1145/2461912.2461982.","ama":"Ando R, Thuerey N, Wojtan C. Highly adaptive liquid simulations on tetrahedral meshes. ACM Transactions on Graphics. 2013;32(4). doi:10.1145/2461912.2461982","apa":"Ando, R., Thuerey, N., & Wojtan, C. (2013). Highly adaptive liquid simulations on tetrahedral meshes. ACM Transactions on Graphics. ACM. https://doi.org/10.1145/2461912.2461982","ieee":"R. Ando, N. Thuerey, and C. Wojtan, “Highly adaptive liquid simulations on tetrahedral meshes,” ACM Transactions on Graphics, vol. 32, no. 4. ACM, 2013.","ista":"Ando R, Thuerey N, Wojtan C. 2013. Highly adaptive liquid simulations on tetrahedral meshes. ACM Transactions on Graphics. 32(4), 103.","chicago":"Ando, Ryoichi, Nils Thuerey, and Chris Wojtan. “Highly Adaptive Liquid Simulations on Tetrahedral Meshes.” ACM Transactions on Graphics. ACM, 2013. https://doi.org/10.1145/2461912.2461982."},"oa_version":"Submitted Version","oa":1,"file":[{"date_updated":"2020-07-14T12:45:41Z","content_type":"application/pdf","file_id":"5279","checksum":"aeea6b0ff2b27c695aeb8408c7d2fc50","relation":"main_file","file_size":8601561,"date_created":"2018-12-12T10:17:25Z","creator":"system","file_name":"IST-2016-605-v1+1_tetflip_fixed.pdf","access_level":"open_access"}],"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","abstract":[{"text":"We introduce a new method for efficiently simulating liquid with extreme amounts of spatial adaptivity. Our method combines several key components to drastically speed up the simulation of large-scale fluid phenomena: We leverage an alternative Eulerian tetrahedral mesh discretization to significantly reduce the complexity of the pressure solve while increasing the robustness with respect to element quality and removing the possibility of locking. Next, we enable subtle free-surface phenomena by deriving novel second-order boundary conditions consistent with our discretization. We couple this discretization with a spatially adaptive Fluid-Implicit Particle (FLIP) method, enabling efficient, robust, minimally-dissipative simulations that can undergo sharp changes in spatial resolution while minimizing artifacts. Along the way, we provide a new method for generating a smooth and detailed surface from a set of particles with variable sizes. Finally, we explore several new sizing functions for determining spatially adaptive simulation resolutions, and we show how to couple them to our simulator. We combine each of these elements to produce a simulation algorithm that is capable of creating animations at high maximum resolutions while avoiding common pitfalls like inaccurate boundary conditions and inefficient computation.","lang":"eng"}],"doi":"10.1145/2461912.2461982","file_date_updated":"2020-07-14T12:45:41Z"},{"issue":"4","pubrep_id":"604","publication":"ACM Transactions on Graphics","intvolume":" 32","publication_status":"published","department":[{"_id":"ChWo"}],"status":"public","publist_id":"4435","year":"2013","date_created":"2018-12-11T11:57:50Z","title":"Putting holes in holey geometry: Topology change for arbitrary surfaces","citation":{"ama":"Bernstein G, Wojtan C. Putting holes in holey geometry: Topology change for arbitrary surfaces. ACM Transactions on Graphics. 2013;32(4). doi:10.1145/2461912.2462027","short":"G. Bernstein, C. Wojtan, ACM Transactions on Graphics 32 (2013).","mla":"Bernstein, Gilbert, and Chris Wojtan. “Putting Holes in Holey Geometry: Topology Change for Arbitrary Surfaces.” ACM Transactions on Graphics, vol. 32, no. 4, 34, ACM, 2013, doi:10.1145/2461912.2462027.","ista":"Bernstein G, Wojtan C. 2013. Putting holes in holey geometry: Topology change for arbitrary surfaces. ACM Transactions on Graphics. 32(4), 34.","chicago":"Bernstein, Gilbert, and Chris Wojtan. “Putting Holes in Holey Geometry: Topology Change for Arbitrary Surfaces.” ACM Transactions on Graphics. ACM, 2013. https://doi.org/10.1145/2461912.2462027.","apa":"Bernstein, G., & Wojtan, C. (2013). Putting holes in holey geometry: Topology change for arbitrary surfaces. ACM Transactions on Graphics. ACM. https://doi.org/10.1145/2461912.2462027","ieee":"G. Bernstein and C. Wojtan, “Putting holes in holey geometry: Topology change for arbitrary surfaces,” ACM Transactions on Graphics, vol. 32, no. 4. ACM, 2013."},"oa_version":"Submitted Version","oa":1,"file":[{"checksum":"9c8425d62246996ca632c5a01870515b","file_id":"4768","creator":"system","access_level":"open_access","file_name":"IST-2016-604-v1+1_toptop2013.pdf","relation":"main_file","file_size":3514674,"date_created":"2018-12-12T10:09:43Z","date_updated":"2020-07-14T12:45:41Z","content_type":"application/pdf"}],"file_date_updated":"2020-07-14T12:45:41Z","doi":"10.1145/2461912.2462027","abstract":[{"text":"This paper presents a method for computing topology changes for triangle meshes in an interactive geometric modeling environment. Most triangle meshes in practice do not exhibit desirable geometric properties, so we develop a solution that is independent of standard assumptions and robust to geometric errors. Specifically, we provide the first method for topology change applicable to arbitrary non-solid, non-manifold, non-closed, self-intersecting surfaces. We prove that this new method for topology change produces the expected conventional results when applied to solid (closed, manifold, non-self-intersecting) surfaces---that is, we prove a backwards-compatibility property relative to prior work. Beyond solid surfaces, we present empirical evidence that our method remains tolerant to a variety of surface aberrations through the incorporation of a novel error correction scheme. Finally, we demonstrate how topology change applied to non-solid objects enables wholly new and useful behaviors.","lang":"eng"}],"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","date_published":"2013-07-01T00:00:00Z","language":[{"iso":"eng"}],"month":"07","day":"01","date_updated":"2023-02-23T10:44:16Z","quality_controlled":"1","ddc":["000"],"article_number":"34","_id":"2467","author":[{"last_name":"Bernstein","full_name":"Bernstein, Gilbert","first_name":"Gilbert"},{"first_name":"Christopher J","orcid":"0000-0001-6646-5546","last_name":"Wojtan","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87"}],"publisher":"ACM","scopus_import":1,"type":"journal_article","volume":32,"has_accepted_license":"1"},{"oa_version":"Submitted Version","date_created":"2018-12-11T11:57:50Z","title":"Liquid surface tracking with error compensation","citation":{"mla":"Bojsen-Hansen, Morten, and Chris Wojtan. “Liquid Surface Tracking with Error Compensation.” ACM Transactions on Graphics, vol. 32, no. 4, 68, ACM, 2013, doi:10.1145/2461912.2461991.","short":"M. Bojsen-Hansen, C. Wojtan, ACM Transactions on Graphics 32 (2013).","ama":"Bojsen-Hansen M, Wojtan C. Liquid surface tracking with error compensation. ACM Transactions on Graphics. 2013;32(4). doi:10.1145/2461912.2461991","ieee":"M. Bojsen-Hansen and C. Wojtan, “Liquid surface tracking with error compensation,” ACM Transactions on Graphics, vol. 32, no. 4. ACM, 2013.","apa":"Bojsen-Hansen, M., & Wojtan, C. (2013). Liquid surface tracking with error compensation. ACM Transactions on Graphics. ACM. https://doi.org/10.1145/2461912.2461991","ista":"Bojsen-Hansen M, Wojtan C. 2013. Liquid surface tracking with error compensation. ACM Transactions on Graphics. 32(4), 68.","chicago":"Bojsen-Hansen, Morten, and Chris Wojtan. “Liquid Surface Tracking with Error Compensation.” ACM Transactions on Graphics. ACM, 2013. https://doi.org/10.1145/2461912.2461991."},"file":[{"content_type":"application/pdf","date_updated":"2020-07-14T12:45:41Z","date_created":"2018-12-12T10:09:37Z","file_size":5813685,"relation":"main_file","access_level":"open_access","file_name":"IST-2016-603-v1+1_liquidError_web.pdf","creator":"system","file_id":"4761","checksum":"53d905e0180e23ef3e813b969ffed4e1"}],"file_date_updated":"2020-07-14T12:45:41Z","doi":"10.1145/2461912.2461991","abstract":[{"text":"Our work concerns the combination of an Eulerian liquid simulation with a high-resolution surface tracker (e.g. the level set method or a Lagrangian triangle mesh). The naive application of a high-resolution surface tracker to a low-resolution velocity field can produce many visually disturbing physical and topological artifacts that limit their use in practice. We address these problems by defining an error function which compares the current state of the surface tracker to the set of physically valid surface states. By reducing this error with a gradient descent technique, we introduce a novel physics-based surface fairing method. Similarly, by treating this error function as a potential energy, we derive a new surface correction force that mimics the vortex sheet equations. We demonstrate our results with both level set and mesh-based surface trackers.","lang":"eng"}],"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","oa":1,"pubrep_id":"603","publication":"ACM Transactions on Graphics","intvolume":" 32","issue":"4","publist_id":"4434","year":"2013","publication_status":"published","department":[{"_id":"ChWo"}],"status":"public","article_number":"68","ddc":["000"],"_id":"2468","quality_controlled":"1","type":"journal_article","scopus_import":1,"volume":32,"has_accepted_license":"1","author":[{"last_name":"Bojsen-Hansen","id":"439F0C8C-F248-11E8-B48F-1D18A9856A87","full_name":"Bojsen-Hansen, Morten","first_name":"Morten","orcid":"0000-0002-4417-3224"},{"id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J","last_name":"Wojtan","orcid":"0000-0001-6646-5546","first_name":"Christopher J"}],"publisher":"ACM","month":"07","date_published":"2013-07-01T00:00:00Z","language":[{"iso":"eng"}],"date_updated":"2023-02-23T10:44:18Z","day":"01"},{"page":"255 - 264","oa":1,"file":[{"date_updated":"2020-07-14T12:46:00Z","content_type":"application/pdf","checksum":"babda64c24cf90a4d05ae86d712bed08","file_id":"4877","creator":"system","access_level":"open_access","file_name":"IST-2016-600-v1+1_ControllingLiquids_Preprint.pdf","relation":"main_file","file_size":4939370,"date_created":"2018-12-12T10:11:23Z"}],"user_id":"3E5EF7F0-F248-11E8-B48F-1D18A9856A87","abstract":[{"lang":"eng","text":"We present an approach for artist-directed animation of liquids using multiple levels of control over the simulation, ranging from the overall tracking of desired shapes to highly detailed secondary effects such as dripping streams, separating sheets of fluid, surface waves and ripples. The first portion of our technique is a volume preserving morph that allows the animator to produce a plausible fluid-like motion from a sparse set of control meshes. By rasterizing the resulting control meshes onto the simulation grid, the mesh velocities act as boundary conditions during the projection step of the fluid simulation. We can then blend this motion together with uncontrolled fluid velocities to achieve a more relaxed control over the fluid that captures natural inertial effects. Our method can produce highly detailed liquid surfaces with control over sub-grid details by using a mesh-based surface tracker on top of a coarse grid-based fluid simulation. We can create ripples and waves on the fluid surface attracting the surface mesh to the control mesh with spring-like forces and also by running a wave simulation over the surface mesh. Our video results demonstrate how our control scheme can be used to create animated characters and shapes that are made of water.\r\n"}],"file_date_updated":"2020-07-14T12:46:00Z","title":"Controlling liquids using meshes","date_created":"2018-12-11T12:01:30Z","citation":{"apa":"Raveendran, K., Thuerey, N., Wojtan, C., & Turk, G. (2012). Controlling liquids using meshes. In Proceedings of the ACM SIGGRAPH/Eurographics Symposium on Computer Animation (pp. 255–264). Aire-la-Ville, Switzerland: ACM.","ieee":"K. Raveendran, N. Thuerey, C. Wojtan, and G. Turk, “Controlling liquids using meshes,” in Proceedings of the ACM SIGGRAPH/Eurographics Symposium on Computer Animation, Aire-la-Ville, Switzerland, 2012, pp. 255–264.","ista":"Raveendran K, Thuerey N, Wojtan C, Turk G. 2012. Controlling liquids using meshes. Proceedings of the ACM SIGGRAPH/Eurographics Symposium on Computer Animation. SCA: ACM SIGGRAPH/Eurographics Symposium on Computer animation, 255–264.","chicago":"Raveendran, Karthik, Nils Thuerey, Chris Wojtan, and Greg Turk. “Controlling Liquids Using Meshes.” In Proceedings of the ACM SIGGRAPH/Eurographics Symposium on Computer Animation, 255–64. ACM, 2012.","short":"K. Raveendran, N. Thuerey, C. Wojtan, G. Turk, in:, Proceedings of the ACM SIGGRAPH/Eurographics Symposium on Computer Animation, ACM, 2012, pp. 255–264.","mla":"Raveendran, Karthik, et al. “Controlling Liquids Using Meshes.” Proceedings of the ACM SIGGRAPH/Eurographics Symposium on Computer Animation, ACM, 2012, pp. 255–64.","ama":"Raveendran K, Thuerey N, Wojtan C, Turk G. Controlling liquids using meshes. In: Proceedings of the ACM SIGGRAPH/Eurographics Symposium on Computer Animation. ACM; 2012:255-264."},"oa_version":"Submitted Version","related_material":{"link":[{"relation":"table_of_contents","url":"http://dl.acm.org/citation.cfm?id=2422393"}]},"publication_status":"published","status":"public","department":[{"_id":"ChWo"}],"year":"2012","publist_id":"3580","publication":"Proceedings of the ACM SIGGRAPH/Eurographics Symposium on Computer Animation","pubrep_id":"600","publisher":"ACM","author":[{"full_name":"Raveendran, Karthik","last_name":"Raveendran","first_name":"Karthik"},{"last_name":"Thuerey","full_name":"Thuerey, Nils","first_name":"Nils"},{"first_name":"Christopher J","orcid":"0000-0001-6646-5546","last_name":"Wojtan","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J"},{"first_name":"Greg","last_name":"Turk","full_name":"Turk, Greg"}],"type":"conference","scopus_import":1,"has_accepted_license":"1","quality_controlled":"1","acknowledgement":"This work was partially funded by NSF grants CCF-0811485 and IIS-1130934. We would like to thank Scanline VFX for additional funding. We would like to thank Jie Tan as well as our anonymous reviewers for their useful suggestions and feedback.","ddc":["000"],"_id":"3119","day":"29","date_updated":"2023-02-23T11:13:07Z","date_published":"2012-07-29T00:00:00Z","language":[{"iso":"eng"}],"conference":{"name":"SCA: ACM SIGGRAPH/Eurographics Symposium on Computer animation","end_date":"2012-07-31","start_date":"2012-07-29","location":"Aire-la-Ville, Switzerland"},"month":"07"},{"month":"07","language":[{"iso":"eng"}],"date_published":"2012-07-01T00:00:00Z","date_updated":"2022-05-24T08:21:11Z","day":"01","_id":"3118","ddc":["000"],"article_number":"53","article_processing_charge":"No","acknowledgement":"This work is supported by the SNF fellowship PBEZP2-134464.\r\nWe would like to thank Xiaochen Hu for implementing mesh con- version tools, Duygu Ceylan for helping with the rendering, and Art Tevs for the human performance data comparison. We also thank Nils Thuerey and Christopher Batty for helpful discussions. ","quality_controlled":"1","has_accepted_license":"1","volume":31,"type":"journal_article","scopus_import":"1","author":[{"orcid":"0000-0002-4417-3224","first_name":"Morten","full_name":"Bojsen-Hansen, Morten","id":"439F0C8C-F248-11E8-B48F-1D18A9856A87","last_name":"Bojsen-Hansen"},{"full_name":"Li, Hao","last_name":"Li","first_name":"Hao"},{"last_name":"Wojtan","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","first_name":"Christopher J","orcid":"0000-0001-6646-5546"}],"publisher":"ACM","intvolume":" 31","pubrep_id":"602","publication":"ACM Transactions on Graphics","issue":"4","publist_id":"3581","year":"2012","status":"public","department":[{"_id":"ChWo"}],"publication_status":"published","oa_version":"Submitted Version","alternative_title":["SIGGRAPH"],"citation":{"apa":"Bojsen-Hansen, M., Li, H., & Wojtan, C. (2012). Tracking surfaces with evolving topology. ACM Transactions on Graphics. ACM. https://doi.org/10.1145/2185520.2185549","ieee":"M. Bojsen-Hansen, H. Li, and C. Wojtan, “Tracking surfaces with evolving topology,” ACM Transactions on Graphics, vol. 31, no. 4. ACM, 2012.","chicago":"Bojsen-Hansen, Morten, Hao Li, and Chris Wojtan. “Tracking Surfaces with Evolving Topology.” ACM Transactions on Graphics. ACM, 2012. https://doi.org/10.1145/2185520.2185549.","ista":"Bojsen-Hansen M, Li H, Wojtan C. 2012. Tracking surfaces with evolving topology. ACM Transactions on Graphics. 31(4), 53.","short":"M. Bojsen-Hansen, H. Li, C. Wojtan, ACM Transactions on Graphics 31 (2012).","mla":"Bojsen-Hansen, Morten, et al. “Tracking Surfaces with Evolving Topology.” ACM Transactions on Graphics, vol. 31, no. 4, 53, ACM, 2012, doi:10.1145/2185520.2185549.","ama":"Bojsen-Hansen M, Li H, Wojtan C. Tracking surfaces with evolving topology. ACM Transactions on Graphics. 2012;31(4). doi:10.1145/2185520.2185549"},"title":"Tracking surfaces with evolving topology","date_created":"2018-12-11T12:01:29Z","doi":"10.1145/2185520.2185549","file_date_updated":"2020-07-14T12:46:00Z","abstract":[{"text":"We present a method for recovering a temporally coherent, deforming triangle mesh with arbitrarily changing topology from an incoherent sequence of static closed surfaces. We solve this problem using the surface geometry alone, without any prior information like surface templates or velocity fields. Our system combines a proven strategy for triangle mesh improvement, a robust multi-resolution non-rigid registration routine, and a reliable technique for changing surface mesh topology. We also introduce a novel topological constraint enforcement algorithm to ensure that the output and input always have similar topology. We apply our technique to a series of diverse input data from video reconstructions, physics simulations, and artistic morphs. The structured output of our algorithm allows us to efficiently track information like colors and displacement maps, recover velocity information, and solve PDEs on the mesh as a post process.","lang":"eng"}],"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","file":[{"content_type":"application/pdf","date_updated":"2020-07-14T12:46:00Z","relation":"main_file","date_created":"2018-12-12T10:18:37Z","file_size":44538518,"creator":"system","file_name":"IST-2016-602-v1+1_topoReg.pdf","access_level":"open_access","file_id":"5359","checksum":"1e219c5bf4e5552c1290c62eefa5cd60"}],"oa":1,"article_type":"original"},{"day":"01","date_updated":"2023-10-16T09:54:40Z","conference":{"location":"Cagliari, Sardinia, Italy","name":"EUROGRAPHICS: Conference on European Association for Computer Graphics","start_date":"2012-05-13","end_date":"2012-05-18"},"language":[{"iso":"eng"}],"date_published":"2012-05-01T00:00:00Z","month":"05","author":[{"full_name":"Yu, Jihun","last_name":"Yu","first_name":"Jihun"},{"orcid":"0000-0001-6646-5546","first_name":"Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J","last_name":"Wojtan"},{"first_name":"Greg","last_name":"Turk","full_name":"Turk, Greg"},{"last_name":"Yap","full_name":"Yap, Chee","first_name":"Chee"}],"publisher":"Wiley","has_accepted_license":"1","volume":31,"type":"conference","scopus_import":"1","article_processing_charge":"No","acknowledgement":"This work was funded by NSF grant IIS-1017014 and CCF- 0917093.","quality_controlled":"1","_id":"3123","publication_identifier":{"eissn":["1467-8659"],"issn":["0167-7055"]},"ddc":["000"],"department":[{"_id":"ChWo"}],"status":"public","publication_status":"published","publist_id":"3576","year":"2012","issue":"2","intvolume":" 31","pubrep_id":"601","publication":"Computer Graphics Forum","oa":1,"page":"815 - 824","file_date_updated":"2020-07-14T12:46:00Z","doi":"10.1111/j.1467-8659.2012.03062.x","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","abstract":[{"text":"We introduce the idea of using an explicit triangle mesh to track the air/fluid interface in a smoothed particle hydrodynamics (SPH) simulator. Once an initial surface mesh is created, this mesh is carried forward in time using nearby particle velocities to advect the mesh vertices. The mesh connectivity remains mostly unchanged across time-steps; it is only modified locally for topology change events or for the improvement of triangle quality. In order to ensure that the surface mesh does not diverge from the underlying particle simulation, we periodically project the mesh surface onto an implicit surface defined by the physics simulation. The mesh surface gives us several advantages over previous SPH surface tracking techniques. We demonstrate a new method for surface tension calculations that clearly outperforms the state of the art in SPH surface tension for computer graphics. We also demonstrate a method for tracking detailed surface information (like colors) that is less susceptible to numerical diffusion than competing techniques. Finally, our temporally-coherent surface mesh allows us to simulate high-resolution surface wave dynamics without being limited by the particle resolution of the SPH simulation.","lang":"eng"}],"file":[{"file_size":5740527,"date_created":"2018-12-12T10:14:39Z","relation":"main_file","access_level":"open_access","file_name":"IST-2016-601-v1+1_meshSPH.pdf","creator":"system","file_id":"5092","checksum":"acb325dd1e31859bedd30e013f61d0b9","content_type":"application/pdf","date_updated":"2020-07-14T12:46:00Z"}],"citation":{"mla":"Yu, Jihun, et al. “Explicit Mesh Surfaces for Particle Based Fluids.” Computer Graphics Forum, vol. 31, no. 2, Wiley, 2012, pp. 815–24, doi:10.1111/j.1467-8659.2012.03062.x.","short":"J. Yu, C. Wojtan, G. Turk, C. Yap, in:, Computer Graphics Forum, Wiley, 2012, pp. 815–824.","ama":"Yu J, Wojtan C, Turk G, Yap C. Explicit mesh surfaces for particle based fluids. In: Computer Graphics Forum. Vol 31. 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EUROGRAPHICS: Conference on European Association for Computer Graphics, Eurographics, vol. 31, 815–824."},"alternative_title":["Eurographics"],"date_created":"2018-12-11T12:01:31Z","title":"Explicit mesh surfaces for particle based fluids","oa_version":"Submitted Version"},{"file_date_updated":"2020-07-14T12:46:06Z","doi":"10.1145/2019406.2019411","abstract":[{"text":"We present a new algorithm for enforcing incompressibility for Smoothed Particle Hydrodynamics (SPH) by preserving uniform density across the domain. We propose a hybrid method that uses a Poisson solve on a coarse grid to enforce a divergence free velocity field, followed by a local density correction of the particles. This avoids typical grid artifacts and maintains the Lagrangian nature of SPH by directly transferring pressures onto particles. Our method can be easily integrated with existing SPH techniques such as the incompressible PCISPH method as well as weakly compressible SPH by adding an additional force term. We show that this hybrid method accelerates convergence towards uniform density and permits a significantly larger time step compared to earlier approaches while producing similar results. We demonstrate our approach in a variety of scenarios with significant pressure gradients such as splashing liquids.","lang":"eng"}],"user_id":"4435EBFC-F248-11E8-B48F-1D18A9856A87","file":[{"creator":"system","access_level":"open_access","file_name":"IST-2016-598-v1+1_HybridSPH_Preprint.pdf","relation":"main_file","date_created":"2018-12-12T10:09:44Z","file_size":2536216,"checksum":"6579d27709946e0eefbfa60a456b4913","file_id":"4769","content_type":"application/pdf","date_updated":"2020-07-14T12:46:06Z"}],"oa":1,"page":"33 - 42","oa_version":"Submitted Version","citation":{"ama":"Raveendran K, Wojtan C, Turk G. Hybrid smoothed particle hydrodynamics. In: Spencer S, ed. ACM; 2011:33-42. doi:10.1145/2019406.2019411","short":"K. Raveendran, C. Wojtan, G. Turk, in:, S. Spencer (Ed.), ACM, 2011, pp. 33–42.","mla":"Raveendran, Karthik, et al. Hybrid Smoothed Particle Hydrodynamics. Edited by Stephen Spencer, ACM, 2011, pp. 33–42, doi:10.1145/2019406.2019411.","ista":"Raveendran K, Wojtan C, Turk G. 2011. Hybrid smoothed particle hydrodynamics. SCA: ACM SIGGRAPH/Eurographics Symposium on Computer animation, 33–42.","chicago":"Raveendran, Karthik, Chris Wojtan, and Greg Turk. “Hybrid Smoothed Particle Hydrodynamics.” edited by Stephen Spencer, 33–42. ACM, 2011. https://doi.org/10.1145/2019406.2019411.","apa":"Raveendran, K., Wojtan, C., & Turk, G. (2011). Hybrid smoothed particle hydrodynamics. In S. Spencer (Ed.) (pp. 33–42). Presented at the SCA: ACM SIGGRAPH/Eurographics Symposium on Computer animation, Vancouver, Canada: ACM. https://doi.org/10.1145/2019406.2019411","ieee":"K. Raveendran, C. Wojtan, and G. Turk, “Hybrid smoothed particle hydrodynamics,” presented at the SCA: ACM SIGGRAPH/Eurographics Symposium on Computer animation, Vancouver, Canada, 2011, pp. 33–42."},"date_created":"2018-12-11T12:02:32Z","title":"Hybrid smoothed particle hydrodynamics","publist_id":"3343","year":"2011","department":[{"_id":"ChWo"}],"status":"public","publication_status":"published","pubrep_id":"598","has_accepted_license":"1","type":"conference","scopus_import":1,"author":[{"full_name":"Raveendran, Karthik","last_name":"Raveendran","first_name":"Karthik"},{"full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","last_name":"Wojtan","orcid":"0000-0001-6646-5546","first_name":"Christopher J"},{"last_name":"Turk","full_name":"Turk, Greg","first_name":"Greg"}],"publisher":"ACM","_id":"3298","ddc":["000"],"quality_controlled":"1","date_updated":"2023-02-23T11:21:05Z","day":"05","editor":[{"full_name":"Spencer, Stephen","last_name":"Spencer","first_name":"Stephen"}],"month":"08","language":[{"iso":"eng"}],"conference":{"name":"SCA: ACM SIGGRAPH/Eurographics Symposium on Computer animation","start_date":"2011-08-05","end_date":"2011-08-07","location":"Vancouver, Canada"},"date_published":"2011-08-05T00:00:00Z"},{"month":"08","conference":{"name":"SIGGRAPH: Special Interest Group on Computer Graphics and Interactive Techniques","start_date":"2011-08-07","end_date":"2011-08-11","location":"Vancouver, BC, Canada"},"language":[{"iso":"eng"}],"date_published":"2011-08-07T00:00:00Z","date_updated":"2023-02-23T11:21:02Z","day":"07","_id":"3297","ddc":["000"],"article_number":"8","quality_controlled":"1","has_accepted_license":"1","type":"conference","scopus_import":1,"author":[{"full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","last_name":"Wojtan","orcid":"0000-0001-6646-5546","first_name":"Christopher J"},{"first_name":"Matthias","full_name":"Müller Fischer, Matthias","last_name":"Müller Fischer"},{"first_name":"Tyson","last_name":"Brochu","full_name":"Brochu, Tyson"}],"publisher":"ACM","pubrep_id":"599","publist_id":"3344","year":"2011","department":[{"_id":"ChWo"}],"status":"public","publication_status":"published","oa_version":"Published Version","citation":{"ieee":"C. Wojtan, M. Müller Fischer, and T. Brochu, “Liquid simulation with mesh-based surface tracking,” presented at the SIGGRAPH: Special Interest Group on Computer Graphics and Interactive Techniques, Vancouver, BC, Canada, 2011.","apa":"Wojtan, C., Müller Fischer, M., & Brochu, T. (2011). Liquid simulation with mesh-based surface tracking. Presented at the SIGGRAPH: Special Interest Group on Computer Graphics and Interactive Techniques, Vancouver, BC, Canada: ACM. https://doi.org/10.1145/2037636.2037644","chicago":"Wojtan, Chris, Matthias Müller Fischer, and Tyson Brochu. “Liquid Simulation with Mesh-Based Surface Tracking.” ACM, 2011. https://doi.org/10.1145/2037636.2037644.","ista":"Wojtan C, Müller Fischer M, Brochu T. 2011. Liquid simulation with mesh-based surface tracking. SIGGRAPH: Special Interest Group on Computer Graphics and Interactive Techniques, 8.","mla":"Wojtan, Chris, et al. Liquid Simulation with Mesh-Based Surface Tracking. 8, ACM, 2011, doi:10.1145/2037636.2037644.","short":"C. Wojtan, M. Müller Fischer, T. Brochu, in:, ACM, 2011.","ama":"Wojtan C, Müller Fischer M, Brochu T. Liquid simulation with mesh-based surface tracking. In: ACM; 2011. doi:10.1145/2037636.2037644"},"title":"Liquid simulation with mesh-based surface tracking","date_created":"2018-12-11T12:02:31Z","file_date_updated":"2020-07-14T12:46:06Z","doi":"10.1145/2037636.2037644","abstract":[{"text":"Animating detailed liquid surfaces has always been a challenge for computer graphics researchers and visual effects artists. Over the past few years, researchers in this field have focused on mesh-based surface tracking to synthesize extremely detailed liquid surfaces as efficiently as possible. This course provides a solid understanding of the steps required to create a fluid simulator with a mesh-based liquid surface.\r\n\r\nThe course begins with an overview of several existing liquid-surface-tracking techniques and the pros and cons of each method. Then it explains how to embed a triangle mesh into a finite-difference-based fluid simulator and describes several methods for allowing the liquid surface to merge together or break apart. The final section showcases the benefits and further applications of a mesh-based liquid surface, highlighting state-of-the-art methods for tracking colors and textures, maintaining liquid volume, preserving small surface features, and simulating realistic surface-tension waves.","lang":"eng"}],"user_id":"3E5EF7F0-F248-11E8-B48F-1D18A9856A87","file":[{"file_id":"5018","checksum":"8d508ad7c82f50978acbaa4170ee0a75","date_created":"2018-12-12T10:13:34Z","file_size":34672096,"relation":"main_file","access_level":"open_access","file_name":"IST-2016-599-v1+1_meshyFluidsCourseSIGGRAPH2011.pdf","creator":"system","date_updated":"2020-07-14T12:46:06Z","content_type":"application/pdf"}],"oa":1},{"intvolume":" 29","month":"07","publication":"ACM Transactions on Graphics","language":[{"iso":"eng"}],"issue":"4","date_published":"2010-07-01T00:00:00Z","extern":"1","publist_id":"2463","date_updated":"2023-02-23T11:41:44Z","year":"2010","status":"public","publication_status":"published","day":"01","_id":"3766","oa_version":"None","citation":{"short":"N. Thürey, C. Wojtan, M. Gross, G. Turk, ACM Transactions on Graphics 29 (2010).","mla":"Thürey, Nils, et al. “A Multiscale Approach to Mesh-Based Surface Tension Flows.” ACM Transactions on Graphics, vol. 29, no. 4, ACM, 2010, doi:10.1145/1778765.1778785.","ama":"Thürey N, Wojtan C, Gross M, Turk G. A multiscale approach to mesh-based surface tension flows. ACM Transactions on Graphics. 2010;29(4). doi:10.1145/1778765.1778785","ieee":"N. Thürey, C. Wojtan, M. Gross, and G. Turk, “A multiscale approach to mesh-based surface tension flows,” ACM Transactions on Graphics, vol. 29, no. 4. ACM, 2010.","apa":"Thürey, N., Wojtan, C., Gross, M., & Turk, G. (2010). A multiscale approach to mesh-based surface tension flows. ACM Transactions on Graphics. ACM. https://doi.org/10.1145/1778765.1778785","chicago":"Thürey, Nils, Chris Wojtan, Markus Gross, and Greg Turk. “A Multiscale Approach to Mesh-Based Surface Tension Flows.” ACM Transactions on Graphics. ACM, 2010. https://doi.org/10.1145/1778765.1778785.","ista":"Thürey N, Wojtan C, Gross M, Turk G. 2010. A multiscale approach to mesh-based surface tension flows. ACM Transactions on Graphics. 29(4)."},"article_processing_charge":"No","title":"A multiscale approach to mesh-based surface tension flows","date_created":"2018-12-11T12:05:03Z","doi":"10.1145/1778765.1778785","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","volume":29,"abstract":[{"text":"We present an approach to simulate flows driven by surface tension based on triangle meshes. Our method consists of two simulation layers: the first layer is an Eulerian method for simulating surface tension forces that is free from typical strict time step constraints. The second simulation layer is a Lagrangian finite element method that simulates sub-grid scale wave details on the fluid surface. The surface wave simulation employs an unconditionally stable, symplectic time integration method that allows for a high propagation speed due to strong surface tension. Our approach can naturally separate the grid-and sub-grid scales based on a volumepreserving mean curvature flow. As our model for the sub-grid dynamics enforces a local conservation of mass, it leads to realistic pinch off and merging effects. In addition to this method for simulating dynamic surface tension effects, we also present an efficient non-oscillatory approximation for capturing damped surface tension behavior. These approaches allow us to efficiently simulate complex phenomena associated with strong surface tension, such as Rayleigh-Plateau instabilities and crown splashes, in a short amount of time.","lang":"eng"}],"type":"journal_article","author":[{"full_name":"Thürey, Nils","last_name":"Thürey","first_name":"Nils"},{"orcid":"0000-0001-6646-5546","first_name":"Christopher J","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","last_name":"Wojtan"},{"first_name":"Markus","full_name":"Gross, Markus","last_name":"Gross"},{"first_name":"Greg","last_name":"Turk","full_name":"Turk, Greg"}],"publisher":"ACM"},{"date_created":"2018-12-11T12:02:31Z","supervisor":[{"first_name":"Irfan","last_name":"Essa","full_name":"Essa, Irfan"},{"full_name":"Liu, Karen","last_name":"Liu","first_name":"Karen"},{"first_name":"Peter","full_name":"Mucha, Peter","last_name":"Mucha"},{"first_name":"Jarek","full_name":"Rossignac, Jarek","last_name":"Rossignac"}],"title":"Animating physical phenomena with embedded surface meshes","article_processing_charge":"No","citation":{"ama":"Wojtan C. Animating physical phenomena with embedded surface meshes. 2010:1-175.","short":"C. Wojtan, Animating Physical Phenomena with Embedded Surface Meshes, Georgia Institute of Technology, 2010.","mla":"Wojtan, Chris. Animating Physical Phenomena with Embedded Surface Meshes. Georgia Institute of Technology, 2010, pp. 1–175.","ista":"Wojtan C. 2010. Animating physical phenomena with embedded surface meshes. Georgia Institute of Technology.","chicago":"Wojtan, Chris. “Animating Physical Phenomena with Embedded Surface Meshes.” Georgia Institute of Technology, 2010.","ieee":"C. Wojtan, “Animating physical phenomena with embedded surface meshes,” Georgia Institute of Technology, 2010.","apa":"Wojtan, C. (2010). Animating physical phenomena with embedded surface meshes. Georgia Institute of Technology."},"oa_version":"None","_id":"3296","main_file_link":[{"url":"http://hdl.handle.net/1853/37256"}],"page":"1 - 175","publisher":"Georgia Institute of Technology","author":[{"last_name":"Wojtan","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","first_name":"Christopher J","orcid":"0000-0001-6646-5546"}],"type":"dissertation","abstract":[{"lang":"eng","text":"Accurate computational representations of highly deformable surfaces are indispensable in the fields of computer animation, medical simulation, computer vision, digital modeling, and computational physics. The focus of this dissertation is on the animation of physics-based phenomena with highly detailed deformable surfaces represented by triangle meshes.\r\n \r\nWe first present results from an algorithm that generates continuum mechanics animations with intricate surface features. This method combines a finite element method with a tetrahedral mesh generator and a high resolution surface mesh, and it is orders of magnitude more efficient than previous approaches. Next, we present an efficient solution for the challenging problem of computing topological changes in detailed dynamic surface meshes. We then introduce a new physics-inspired surface tracking algorithm that is capable of preserving arbitrarily thin features and reproducing realistic fine-scale topological changes like Rayleigh-Plateau instabilities. This physics-inspired surface tracking technique also opens the door for a unique coupling between surficial finite element methods and volumetric finite difference methods, in order to simulate liquid surface tension phenomena more efficiently than any previous method. Due to its dramatic increase in computational resolution and efficiency, this method yielded the first computer simulations of a fully developed crown splash with droplet pinch off."}],"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","date_published":"2010-11-17T00:00:00Z","language":[{"iso":"eng"}],"month":"11","publication_status":"published","day":"17","status":"public","year":"2010","date_updated":"2023-02-23T11:21:00Z","publist_id":"3345","extern":"1"},{"intvolume":" 16","month":"01","publication":"IEEE Transactions on Visualization and Computer Graphics","language":[{"iso":"eng"}],"issue":"1","date_published":"2010-01-01T00:00:00Z","extern":"1","publist_id":"2468","date_updated":"2023-02-23T11:41:31Z","year":"2010","status":"public","publication_status":"published","day":"01","_id":"3761","oa_version":"None","citation":{"mla":"Kwatra, Nipun, et al. “Fluid Simulation with Articulated Bodies.” IEEE Transactions on Visualization and Computer Graphics, vol. 16, no. 1, IEEE, 2010, pp. 70–80, doi:10.1109/TVCG.2009.66.","short":"N. Kwatra, C. Wojtan, M. Carlson, I. Essa, P. Mucha, G. Turk, IEEE Transactions on Visualization and Computer Graphics 16 (2010) 70–80.","ama":"Kwatra N, Wojtan C, Carlson M, Essa I, Mucha P, Turk G. Fluid simulation with articulated bodies. IEEE Transactions on Visualization and Computer Graphics. 2010;16(1):70-80. doi:10.1109/TVCG.2009.66","apa":"Kwatra, N., Wojtan, C., Carlson, M., Essa, I., Mucha, P., & Turk, G. (2010). Fluid simulation with articulated bodies. IEEE Transactions on Visualization and Computer Graphics. IEEE. https://doi.org/10.1109/TVCG.2009.66","ieee":"N. Kwatra, C. Wojtan, M. Carlson, I. Essa, P. Mucha, and G. Turk, “Fluid simulation with articulated bodies,” IEEE Transactions on Visualization and Computer Graphics, vol. 16, no. 1. IEEE, pp. 70–80, 2010.","chicago":"Kwatra, Nipun, Chris Wojtan, Mark Carlson, Irfan Essa, Peter Mucha, and Greg Turk. “Fluid Simulation with Articulated Bodies.” IEEE Transactions on Visualization and Computer Graphics. IEEE, 2010. https://doi.org/10.1109/TVCG.2009.66.","ista":"Kwatra N, Wojtan C, Carlson M, Essa I, Mucha P, Turk G. 2010. Fluid simulation with articulated bodies. IEEE Transactions on Visualization and Computer Graphics. 16(1), 70–80."},"article_processing_charge":"No","title":"Fluid simulation with articulated bodies","date_created":"2018-12-11T12:05:01Z","doi":"10.1109/TVCG.2009.66","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","abstract":[{"text":"We present an algorithm for creating realistic animations of characters that are swimming through fluids. Our approach combines dynamic simulation with data-driven kinematic motions (motion capture data) to produce realistic animation in a fluid. The interaction of the articulated body with the fluid is performed by incorporating joint constraints with rigid animation and by extending a solid/fluid coupling method to handle articulated chains. Our solver takes as input the current state of the simulation and calculates the angular and linear accelerations of the connected bodies needed to match a particular motion sequence for the articulated body. These accelerations are used to estimate the forces and torques that are then applied to each joint. Based on this approach, we demonstrate simulated swimming results for a variety of different strokes, including crawl, backstroke, breaststroke, and butterfly. The ability to have articulated bodies interact with fluids also allows us to generate simulations of simple water creatures that are driven by simple controllers.","lang":"eng"}],"volume":16,"type":"journal_article","author":[{"full_name":"Kwatra, Nipun","last_name":"Kwatra","first_name":"Nipun"},{"first_name":"Christopher J","orcid":"0000-0001-6646-5546","last_name":"Wojtan","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87"},{"first_name":"Mark","last_name":"Carlson","full_name":"Carlson, Mark"},{"first_name":"Irfan","last_name":"Essa","full_name":"Essa, Irfan"},{"first_name":"Peter","full_name":"Mucha, Peter","last_name":"Mucha"},{"first_name":"Greg","full_name":"Turk, Greg","last_name":"Turk"}],"publisher":"IEEE","page":"70 - 80"},{"citation":{"ista":"Wojtan C, Thürey N, Gross M, Turk G. 2010. Physics-inspired topology changes for thin fluid features. ACM Transactions on Graphics. 29(4).","chicago":"Wojtan, Chris, Nils Thürey, Markus Gross, and Greg Turk. “Physics-Inspired Topology Changes for Thin Fluid Features.” ACM Transactions on Graphics. ACM, 2010. https://doi.org/10.1145/1778765.1778787.","ieee":"C. Wojtan, N. Thürey, M. Gross, and G. Turk, “Physics-inspired topology changes for thin fluid features,” ACM Transactions on Graphics, vol. 29, no. 4. ACM, 2010.","apa":"Wojtan, C., Thürey, N., Gross, M., & Turk, G. (2010). Physics-inspired topology changes for thin fluid features. ACM Transactions on Graphics. ACM. https://doi.org/10.1145/1778765.1778787","ama":"Wojtan C, Thürey N, Gross M, Turk G. Physics-inspired topology changes for thin fluid features. ACM Transactions on Graphics. 2010;29(4). doi:10.1145/1778765.1778787","short":"C. Wojtan, N. Thürey, M. Gross, G. Turk, ACM Transactions on Graphics 29 (2010).","mla":"Wojtan, Chris, et al. “Physics-Inspired Topology Changes for Thin Fluid Features.” ACM Transactions on Graphics, vol. 29, no. 4, ACM, 2010, doi:10.1145/1778765.1778787."},"article_processing_charge":"No","date_created":"2018-12-11T12:05:00Z","title":"Physics-inspired topology changes for thin fluid features","_id":"3759","main_file_link":[{"url":"http://kucg.korea.ac.kr/seminar/2010/src/paper-2010-09-02.pdf"}],"oa_version":"None","author":[{"first_name":"Christopher J","orcid":"0000-0001-6646-5546","last_name":"Wojtan","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J"},{"first_name":"Nils","full_name":"Thürey, Nils","last_name":"Thürey"},{"first_name":"Markus","last_name":"Gross","full_name":"Gross, Markus"},{"first_name":"Greg","last_name":"Turk","full_name":"Turk, Greg"}],"publisher":"ACM","doi":"10.1145/1778765.1778787","abstract":[{"text":"We propose a mesh-based surface tracking method for fluid animation that both preserves fine surface details and robustly adjusts the topology of the surface in the presence of arbitrarily thin features like sheets and strands. We replace traditional re-sampling methods with a convex hull method for connecting surface features during topological changes. This technique permits arbitrarily thin fluid features with minimal re-sampling errors by reusing points from the original surface. We further reduce re-sampling artifacts with a subdivision-based mesh-stitching algorithm, and we use a higher order interpolating subdivision scheme to determine the location of any newly-created vertices. The resulting algorithm efficiently produces detailed fluid surfaces with arbitrarily thin features while maintaining a consistent topology with the underlying fluid simulation.","lang":"eng"}],"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","volume":29,"type":"journal_article","language":[{"iso":"eng"}],"issue":"4","date_published":"2010-01-01T00:00:00Z","intvolume":" 29","month":"01","publication":"ACM Transactions on Graphics","status":"public","day":"01","publication_status":"published","extern":"1","date_updated":"2023-02-23T11:41:24Z","publist_id":"2470","year":"2010"},{"issue":"3","date_published":"2009-08-01T00:00:00Z","language":[{"iso":"eng"}],"month":"08","publication":"ACM Transactions on Graphics","intvolume":" 28","day":"01","publication_status":"published","status":"public","date_updated":"2023-02-23T11:41:39Z","publist_id":"2466","year":"2009","extern":"1","title":"Deforming meshes that split and merge","date_created":"2018-12-11T12:05:02Z","citation":{"short":"C. Wojtan, N. Thürey, M. Gross, G. Turk, ACM Transactions on Graphics 28 (2009).","mla":"Wojtan, Chris, et al. “Deforming Meshes That Split and Merge.” ACM Transactions on Graphics, vol. 28, no. 3, ACM, 2009, doi:10.1145/1531326.1531382.","ama":"Wojtan C, Thürey N, Gross M, Turk G. Deforming meshes that split and merge. ACM Transactions on Graphics. 2009;28(3). doi:10.1145/1531326.1531382","ieee":"C. Wojtan, N. Thürey, M. Gross, and G. Turk, “Deforming meshes that split and merge,” ACM Transactions on Graphics, vol. 28, no. 3. ACM, 2009.","apa":"Wojtan, C., Thürey, N., Gross, M., & Turk, G. (2009). Deforming meshes that split and merge. ACM Transactions on Graphics. ACM. https://doi.org/10.1145/1531326.1531382","chicago":"Wojtan, Chris, Nils Thürey, Markus Gross, and Greg Turk. “Deforming Meshes That Split and Merge.” ACM Transactions on Graphics. ACM, 2009. https://doi.org/10.1145/1531326.1531382.","ista":"Wojtan C, Thürey N, Gross M, Turk G. 2009. Deforming meshes that split and merge. ACM Transactions on Graphics. 28(3)."},"article_processing_charge":"No","oa_version":"None","_id":"3764","author":[{"orcid":"0000-0001-6646-5546","first_name":"Christopher J","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","last_name":"Wojtan"},{"full_name":"Thürey, Nils","last_name":"Thürey","first_name":"Nils"},{"last_name":"Gross","full_name":"Gross, Markus","first_name":"Markus"},{"first_name":"Greg","full_name":"Turk, Greg","last_name":"Turk"}],"publisher":"ACM","type":"journal_article","doi":"10.1145/1531326.1531382","abstract":[{"text":"We present a method for accurately tracking the moving surface of deformable materials in a manner that gracefully handles topological changes. We employ a Lagrangian surface tracking method, and we use a triangle mesh for our surface representation so that fine features can be retained. We make topological changes to the mesh by first identifying merging or splitting events at a particular grid resolution, and then locally creating new pieces of the mesh in the affected cells using a standard isosurface creation method. We stitch the new, topologically simplified portion of the mesh to the rest of the mesh at the cell boundaries. Our method detects and treats topological events with an emphasis on the preservation of detailed features, while simultaneously simplifying those portions of the material that are not visible. Our surface tracker is not tied to a particular method for simulating deformable materials. In particular, we show results from two significantly different simulators: a Lagrangian FEM simulator with tetrahedral elements, and an Eulerian grid-based fluid simulator. Although our surface tracking method is generic, it is particularly well-suited for simulations that exhibit fine surface details and numerous topological events. Highlights of our results include merging of viscoplastic materials with complex geometry, a taffy-pulling animation with many fold and merge events, and stretching and slicing of stiff plastic material.","lang":"eng"}],"volume":28,"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87"},{"date_updated":"2023-02-23T11:41:29Z","publist_id":"2467","year":"2008","extern":"1","day":"01","publication_status":"published","status":"public","month":"08","publication":"ACM Transactions on Graphics","intvolume":" 27","issue":"3","date_published":"2008-08-01T00:00:00Z","language":[{"iso":"eng"}],"type":"journal_article","doi":"10.1145/1360612.1360646","volume":27,"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","abstract":[{"lang":"eng","text":"We introduce a method for efficiently animating a wide range of deformable materials. We combine a high resolution surface mesh with a tetrahedral finite element simulator that makes use of frequent re-meshing. This combination allows for fast and detailed simulations of complex elastic and plastic behavior. We significantly expand the range of physical parameters that can be simulated with a single technique, and the results are free from common artifacts such as volume-loss, smoothing, popping, and the absence of thin features like strands and sheets. Our decision to couple a high resolution surface with low-resolution physics leads to efficient simulation and detailed surface features, and our approach to creating the tetrahedral mesh leads to an order-of-magnitude speedup over previous techniques in the time spent re-meshing. We compute masses, collisions, and surface tension forces on the scale of the fine mesh, which helps avoid visual artifacts due to the differing mesh resolutions. The result is a method that can simulate a large array of different material behaviors with high resolution features in a short amount of time."}],"author":[{"last_name":"Wojtan","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","first_name":"Christopher J","orcid":"0000-0001-6646-5546"},{"last_name":"Turk","full_name":"Turk, Greg","first_name":"Greg"}],"publisher":"ACM","oa_version":"None","main_file_link":[{"url":"http://www.cc.gatech.edu/~turk/my_papers/fast_goop_2008.pdf"}],"_id":"3760","title":"Fast viscoelastic behavior with thin features","date_created":"2018-12-11T12:05:01Z","citation":{"ieee":"C. Wojtan and G. Turk, “Fast viscoelastic behavior with thin features,” ACM Transactions on Graphics, vol. 27, no. 3. ACM, 2008.","apa":"Wojtan, C., & Turk, G. (2008). Fast viscoelastic behavior with thin features. ACM Transactions on Graphics. ACM. https://doi.org/10.1145/1360612.1360646","ista":"Wojtan C, Turk G. 2008. Fast viscoelastic behavior with thin features. ACM Transactions on Graphics. 27(3).","chicago":"Wojtan, Chris, and Greg Turk. “Fast Viscoelastic Behavior with Thin Features.” ACM Transactions on Graphics. ACM, 2008. https://doi.org/10.1145/1360612.1360646.","short":"C. Wojtan, G. Turk, ACM Transactions on Graphics 27 (2008).","mla":"Wojtan, Chris, and Greg Turk. “Fast Viscoelastic Behavior with Thin Features.” ACM Transactions on Graphics, vol. 27, no. 3, ACM, 2008, doi:10.1145/1360612.1360646.","ama":"Wojtan C, Turk G. Fast viscoelastic behavior with thin features. ACM Transactions on Graphics. 2008;27(3). doi:10.1145/1360612.1360646"},"article_processing_charge":"No"},{"extern":"1","year":"2007","publist_id":"2462","date_updated":"2023-02-23T11:41:41Z","status":"public","publication_status":"published","day":"29","intvolume":" 26","publication":"ACM Transactions on Graphics","month":"07","language":[{"iso":"eng"}],"date_published":"2007-07-29T00:00:00Z","issue":"3","volume":26,"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","abstract":[{"text":"We present an extension to Lagrangian finite element methods to allow for large plastic deformations of solid materials. These behaviors are seen in such everyday materials as shampoo, dough, and clay as well as in fantastic gooey and blobby creatures in special effects scenes. To account for plastic deformation, we explicitly update the linear basis functions defined over the finite elements during each simulation step. When these updates cause the basis functions to become ill-conditioned, we remesh the simulation domain to produce a new high-quality finite-element mesh, taking care to preserve the original boundary. We also introduce an enhanced plasticity model that preserves volume and includes creep and work hardening/softening. We demonstrate our approach with simulations of synthetic objects that squish, dent, and flow. To validate our methods, we compare simulation results to videos of real materials.","lang":"eng"}],"doi":"10.1145/1276377.1276397","type":"journal_article","publisher":"ACM","author":[{"first_name":"Adam","last_name":"Bargteil","full_name":"Bargteil, Adam"},{"last_name":"Wojtan","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","first_name":"Christopher J","orcid":"0000-0001-6646-5546"},{"first_name":"Jessica","full_name":"Hodgins, Jessica","last_name":"Hodgins"},{"full_name":"Turk, Greg","last_name":"Turk","first_name":"Greg"}],"_id":"3765","oa_version":"None","citation":{"apa":"Bargteil, A., Wojtan, C., Hodgins, J., & Turk, G. (2007). A finite element method for animating large viscoplastic flow. ACM Transactions on Graphics. ACM. https://doi.org/10.1145/1276377.1276397","ieee":"A. Bargteil, C. Wojtan, J. Hodgins, and G. Turk, “A finite element method for animating large viscoplastic flow,” ACM Transactions on Graphics, vol. 26, no. 3. ACM, 2007.","chicago":"Bargteil, Adam, Chris Wojtan, Jessica Hodgins, and Greg Turk. “A Finite Element Method for Animating Large Viscoplastic Flow.” ACM Transactions on Graphics. ACM, 2007. https://doi.org/10.1145/1276377.1276397.","ista":"Bargteil A, Wojtan C, Hodgins J, Turk G. 2007. A finite element method for animating large viscoplastic flow. ACM Transactions on Graphics. 26(3).","short":"A. Bargteil, C. Wojtan, J. Hodgins, G. Turk, ACM Transactions on Graphics 26 (2007).","mla":"Bargteil, Adam, et al. “A Finite Element Method for Animating Large Viscoplastic Flow.” ACM Transactions on Graphics, vol. 26, no. 3, ACM, 2007, doi:10.1145/1276377.1276397.","ama":"Bargteil A, Wojtan C, Hodgins J, Turk G. A finite element method for animating large viscoplastic flow. ACM Transactions on Graphics. 2007;26(3). doi:10.1145/1276377.1276397"},"article_processing_charge":"No","date_created":"2018-12-11T12:05:03Z","title":"A finite element method for animating large viscoplastic flow"},{"publisher":"Eurographics Association","author":[{"last_name":"Wojtan","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J","first_name":"Christopher J","orcid":"0000-0001-6646-5546"},{"last_name":"Carlson","full_name":"Carlson, Mark","first_name":"Mark"},{"first_name":"Peter","last_name":"Mucha","full_name":"Mucha, Peter"},{"first_name":"Greg","full_name":"Turk, Greg","last_name":"Turk"}],"page":"15 - 22","abstract":[{"text":"In this paper, we present a simple method for animating natural phenomena such as erosion, sedimentation, and acidic corrosion. We discretize the appropriate physical or chemical equations using finite differences, and we use the results to modify the shape of a solid body. We remove mass from an object by treating its surface as a level set and advecting it inward, and we deposit the chemical and physical byproducts into simulated fluid. Similarly, our technique deposits sediment onto a surface by advecting the level set outward. Our idea can be used for off-line high quality animations as well as interactive applications such as games, and we demonstrate both in this paper.","lang":"eng"}],"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","doi":"10.2312/NPH/NPH07/015-022","type":"conference","article_processing_charge":"No","citation":{"ama":"Wojtan C, Carlson M, Mucha P, Turk G. Animating corrosion and erosion. In: Eurographics Association; 2007:15-22. doi:10.2312/NPH/NPH07/015-022","mla":"Wojtan, Chris, et al. Animating Corrosion and Erosion. Eurographics Association, 2007, pp. 15–22, doi:10.2312/NPH/NPH07/015-022.","short":"C. Wojtan, M. Carlson, P. Mucha, G. Turk, in:, Eurographics Association, 2007, pp. 15–22.","chicago":"Wojtan, Chris, Mark Carlson, Peter Mucha, and Greg Turk. “Animating Corrosion and Erosion,” 15–22. Eurographics Association, 2007. https://doi.org/10.2312/NPH/NPH07/015-022.","ista":"Wojtan C, Carlson M, Mucha P, Turk G. 2007. Animating corrosion and erosion. EGWNP: Eurographics Workshop on Natural Phenomena, 15–22.","apa":"Wojtan, C., Carlson, M., Mucha, P., & Turk, G. (2007). Animating corrosion and erosion (pp. 15–22). Presented at the EGWNP: Eurographics Workshop on Natural Phenomena, Eurographics Association. https://doi.org/10.2312/NPH/NPH07/015-022","ieee":"C. Wojtan, M. Carlson, P. Mucha, and G. Turk, “Animating corrosion and erosion,” presented at the EGWNP: Eurographics Workshop on Natural Phenomena, 2007, pp. 15–22."},"date_created":"2018-12-11T12:05:02Z","title":"Animating corrosion and erosion","_id":"3762","main_file_link":[{"url":"http://www.amath.unc.edu/Faculty/mucha/Reprints/EGNPerosion.pdf"}],"oa_version":"None","status":"public","day":"01","publication_status":"published","extern":"1","year":"2007","publist_id":"2464","date_updated":"2023-02-23T11:41:34Z","conference":{"name":"EGWNP: Eurographics Workshop on Natural Phenomena"},"language":[{"iso":"eng"}],"date_published":"2007-09-01T00:00:00Z","month":"09"},{"_id":"3758","main_file_link":[{"url":"http://www.amath.unc.edu/Faculty/mucha/Reprints/SCAclothcontrolpreprint.pdf"}],"oa_version":"None","article_processing_charge":"No","citation":{"chicago":"Wojtan, Chris, Peter Mucha, and Greg Turk. “Keyframe Control of Complex Particle Systems Using the Adjoint Method,” 15–23. ACM, 2006.","ista":"Wojtan C, Mucha P, Turk G. 2006. Keyframe control of complex particle systems using the adjoint method. SCA: ACM SIGGRAPH/Eurographics Symposium on Computer animation, 15–23.","apa":"Wojtan, C., Mucha, P., & Turk, G. (2006). Keyframe control of complex particle systems using the adjoint method (pp. 15–23). Presented at the SCA: ACM SIGGRAPH/Eurographics Symposium on Computer animation, ACM.","ieee":"C. Wojtan, P. Mucha, and G. Turk, “Keyframe control of complex particle systems using the adjoint method,” presented at the SCA: ACM SIGGRAPH/Eurographics Symposium on Computer animation, 2006, pp. 15–23.","ama":"Wojtan C, Mucha P, Turk G. Keyframe control of complex particle systems using the adjoint method. In: ACM; 2006:15-23.","short":"C. Wojtan, P. Mucha, G. Turk, in:, ACM, 2006, pp. 15–23.","mla":"Wojtan, Chris, et al. Keyframe Control of Complex Particle Systems Using the Adjoint Method. ACM, 2006, pp. 15–23."},"title":"Keyframe control of complex particle systems using the adjoint method","date_created":"2018-12-11T12:05:00Z","abstract":[{"lang":"eng","text":"Control of physical simulation has become a popular topic in the field of computer graphics. Keyframe control has been applied to simulations of rigid bodies, smoke, liquid, flocks, and finite element-based elastic bodies. In this paper, we create a framework for controlling systems of interacting particles -- paying special attention to simulations of cloth and flocking behavior. We introduce a novel integrator-swapping approximation in order to apply the adjoint method to linearized implicit schemes appropriate for cloth simulation. This allows the control of cloth while avoiding computationally infeasible derivative calculations. Meanwhile, flocking control using the adjoint method is significantly more efficient than currently-used methods for constraining group behaviors, allowing the controlled simulation of greater numbers of agents in fewer optimization iterations."}],"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","type":"conference","author":[{"id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","full_name":"Wojtan, Christopher J","last_name":"Wojtan","orcid":"0000-0001-6646-5546","first_name":"Christopher J"},{"last_name":"Mucha","full_name":"Mucha, Peter","first_name":"Peter"},{"first_name":"Greg","full_name":"Turk, Greg","last_name":"Turk"}],"publisher":"ACM","page":"15 - 23","month":"09","language":[{"iso":"eng"}],"conference":{"name":"SCA: ACM SIGGRAPH/Eurographics Symposium on Computer animation"},"date_published":"2006-09-01T00:00:00Z","extern":"1","publist_id":"2469","date_updated":"2023-02-23T11:41:22Z","year":"2006","status":"public","publication_status":"published","day":"01"},{"day":"01","publication_status":"published","status":"public","date_updated":"2023-02-23T11:41:36Z","publist_id":"2465","year":"2005","extern":"1","issue":"7","date_published":"2005-08-01T00:00:00Z","language":[{"iso":"eng"}],"month":"08","publication":"The Visual Computer","intvolume":" 21","page":"474 - 487","author":[{"full_name":"Shi, Lin","last_name":"Shi","first_name":"Lin"},{"full_name":"Yu, Yizhou","last_name":"Yu","first_name":"Yizhou"},{"last_name":"Wojtan","full_name":"Wojtan, Christopher J","id":"3C61F1D2-F248-11E8-B48F-1D18A9856A87","first_name":"Christopher J","orcid":"0000-0001-6646-5546"},{"first_name":"Stephen","full_name":"Chenney, Stephen","last_name":"Chenney"}],"publisher":"Springer","type":"journal_article","doi":"10.1007/s00371-005-0296-0","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","abstract":[{"lang":"eng","text":"The generation of realistic motion satisfying user-defined requirements is one of the most important goals of computer animation. Our aim in this paper is the synthesis of realistic, controllable motion for lightweight natural objects in a gaseous medium. We formulate this problem as a large-scale spacetime optimization with user controls and fluid motion equations as constraints. We have devised novel and effective methods to make this large optimization tractable. Initial trajectories are generated with data-driven synthesis based on stylistic motion planning. Smoothed particle hydrodynamics (SPH) is used during optimization to produce fluid simulations at a reasonable computational cost, while interesting vortex-based fluid motion is generated by recording the presence of vortices in the initial trajectories and maintaining them through optimization. Object rotations are refined as a postprocess to enhance the visual quality of the results. We demonstrate our techniques on a number of animations involving single or multiple objects."}],"volume":21,"date_created":"2018-12-11T12:05:02Z","title":"Controllable motion synthesis in a gaseous medium","citation":{"short":"L. Shi, Y. Yu, C. Wojtan, S. Chenney, The Visual Computer 21 (2005) 474–487.","mla":"Shi, Lin, et al. “Controllable Motion Synthesis in a Gaseous Medium.” The Visual Computer, vol. 21, no. 7, Springer, 2005, pp. 474–87, doi:10.1007/s00371-005-0296-0.","ama":"Shi L, Yu Y, Wojtan C, Chenney S. Controllable motion synthesis in a gaseous medium. The Visual Computer. 2005;21(7):474-487. doi:10.1007/s00371-005-0296-0","ieee":"L. Shi, Y. Yu, C. Wojtan, and S. Chenney, “Controllable motion synthesis in a gaseous medium,” The Visual Computer, vol. 21, no. 7. Springer, pp. 474–487, 2005.","apa":"Shi, L., Yu, Y., Wojtan, C., & Chenney, S. (2005). Controllable motion synthesis in a gaseous medium. The Visual Computer. Springer. https://doi.org/10.1007/s00371-005-0296-0","chicago":"Shi, Lin, Yizhou Yu, Chris Wojtan, and Stephen Chenney. “Controllable Motion Synthesis in a Gaseous Medium.” The Visual Computer. Springer, 2005. https://doi.org/10.1007/s00371-005-0296-0.","ista":"Shi L, Yu Y, Wojtan C, Chenney S. 2005. Controllable motion synthesis in a gaseous medium. The Visual Computer. 21(7), 474–487."},"article_processing_charge":"No","oa_version":"None","_id":"3763"}]