# Assistant conversation 229MJ4 - Canonical URL: - Resource IRI: - Type: assistant conversation - Mode: quick ## Transcript ### 1. User hey can you gimme an overview of the papers we have here? ### 2. Assistant tool calls #### Tool call: `list_documents` ```json {} ``` ### 3. Tool result: get_document DOCUMENT #9YMD2E Title: SNAP and SPAN: Towards Dynamic Spatial Ontology Outline: - 1 #RBL6PZ SNAP and SPAN: Towards Dynamic Spatial Ontology - 1.1 #K6SSVN 1 Philosophical Background - 1.1.1 #GFRTYB Basic Formal Ontology - 1.1.2 #DK4RJ9 Temporal Modes of Being - 1.1.3 #PYHEWY Spatiotemporal Ontologies in BFO - 1.1.4 #26SD7J Granularity and Ontological Zooming - 1.1.5 #9SZRQM Taxonomies of SNAP and SPAN - 1.2 #395KH6 2 Formal Framework for BFO - 1.2.1 #KQ4RXW 2.1 Entities and Ontologies - 1.2.1.1 #2UAYWR Ontologies and Ontology Forms - 1.2.1.2 #5QDPLY Material Universals - 1.2.1.3 #XZBGMM Taxonomies of Universals in BFO - 1.2.2 #Y9WM7Q 2.2 Mereology - 1.2.2.1 #QNNQ5Y Mereology and Universals - 1.2.3 #BK3QCV 2.3 Formal Relations - 1.2.3.1 #9AERBS Ontological Indices of Relations. - 1.3 #QZ35CZ 3 SNAP - 1.3.1 #UQH4XU 3.1 Spatial Regions - 1.3.2 #LGE6EY 3.2 Substantial Entities - 1.3.3 #CAHEN5 3.3 SNAP Dependent Entities - 1.3.4 #P4DE3U 3.4 Universals - 1.4 #35MC29 4 SPAN - 1.4.1 #FV9PQR 4.1 Processual Entities - 1.4.2 #QLNXDB 4.3 Temporal Regions - 1.4.3 #WWCQX4 4.4 Spatiotemporal Regions - 1.5 #4NQATC 5 Trans-Ontology in BFO - 1.5.1 #5YQFU8 SNAP-SNAP Trans-Ontology - 1.5.1.1 #LFHHPS Qualitative Change - 1.5.1.2 #VZ3SDB Spatial and Locational Change - 1.5.1.3 #FHYAX6 Substantial Change - 1.5.2 #4WUBEQ Genidentity - 1.5.3 #3YPE9U Reasoning with SPAN Ontologies - 1.5.4 #854NA2 SNAP-SPAN Trans-ontology - 1.6 #XVCM25 6 Case Study: The Ontology of Geodynamic - 1.6.1 #UYMYEH Geographical Ontology - 1.6.2 #BS2RJT 6.1 Georegions and Geo-Ontologies - 1.6.2.1 #PKYEV9 Geospatial Regions. - 1.6.2.2 #4D6KJ8 Geotemporal and Geospatiotemporal Regions - 1.6.2.3 #684DED Geo-Ontologies - 1.6.3 #7MRJ7Z 6.3 The SNAP Geographical Object Ontology - 1.6.4 #YVHQGW 6.4 The SPAN Geographical Process Ontology - 1.6.4.1 #BGCHQQ Patterns and Features of Processes - 1.6.5 #DUUBT3 6.5 The SNAP Geographical Fields Ontology - 1.6.5.1 #UMMP8H Relations in SNAP Field Ontologies. - 1.7 #QU7ELJ Conclusion - 1.8 #TCMAHV Acknowledgements - 1.9 #UDNAWL References ### 4. Assistant tool calls #### Tool call: `read` ```json { "blocks": [ "K6SSVN", "QU7ELJ" ], "expand": true } ``` ### 5. Tool result: list_documents Journal articles (25) - #RBS5K6 A Layered Particle-Based Fluid Model for Real-Time Rendering of Water - 2010 | Daniel Scherzer, Florian Bagar, Michael Wimmer | Computer Graphics Forum | 7 pp. | doi:10.1111/j.1467-8659.2010.01734.x - #G3TBNG A Sequential Two-Step Algorithm for Fast Generation of Vehicle Racing Trajectories - 2016 | J. Christian Gerdes, John Subosits, Nitin R. Kapania | Journal of Dynamic Systems, Measurement, and Control | 12 pp. | doi:10.1115/1.4033311 - #C4AY2M A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics - 2011 | B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato | Computer Graphics Forum | 17 pp. | doi:10.1111/j.1467-8659.2010.01828.x - #B6P8L4 Active walker model for the formation of human and animal trail systems - 1997 | Dirk Helbing, Frank Schweitzer, Joachim Keltsch, Péter Molnár | Physical Review E | 34 pp. | doi:10.1103/physreve.56.2527 - #WZMZGY Advected river textures - 2009 | Dirk Arnold, Stephen Brooks, Tim Burrell | Computer Animation and Virtual Worlds | 11 pp. | doi:10.1002/cav.288 - #MH5J8D Beautimeter: Harnessing GPT for Assessing Architectural and Urban Beauty Based on the 15 Properties of Living Structure - 2025 | Bin Jiang | AI | 12 pp. | doi:10.3390/ai6040074 - #NV2YRW FastFlow: GPU Acceleration of Flow and Depression Routing for Landscape Simulation - 2024 | Aryamaan Jain, Bernhard Kerbl, Brandon Finley, Guillaume Cordonnier, James Gain | Computer Graphics Forum | 13 pp. | doi:10.1111/cgf.15243 - #SKRF4C Geography as a Science of the Earth’s Surface Founded on the Third View of Space - 2022 | Bin Jiang | Annals of GIS | 14 pp. | doi:10.1080/19475683.2021.1966502 - #V4TQYB Interactive procedural street modeling - 2008 | Eugene Zhang, Gregory Esch, Guoning Chen, Pascal Müller, Peter Wonka | ACM Transactions on Graphics | 10 pp. | doi:10.1145/1360612.1360702 - #92XRH7 Lagrangian Texture Advection: Preserving both Spectrum and Velocity Field - 2011 | Qizhi Yu, E. Bruneton, F. Neyret, N. Holzschuch | IEEE Transactions on Visualization and Computer Graphics | 13 pp. | doi:10.1109/tvcg.2010.263 - #96ZMGK Large Scale Terrain Generation from Tectonic Uplift and Fluvial Erosion - 2016 | Adrien Peytavie, Bedrich Benes, Guillaume Cordonnier, Jean Braun, Marie-Paule Cani, Éric Galin, Éric Guérin | Computer Graphics Forum | 11 pp. | doi:10.1111/cgf.12820 - #MJKTBB Living Images: A Recursive Approach to Computing the Structural Beauty of Images or the Livingness of Space - 2023 | Bin Jiang, Chris de Rijke | Annals of the American Association of Geographers | 19 pp. | doi:10.1080/24694452.2023.2178376 - #UYLTYJ Modelling the Evolution of Human Trail Systems - 1997 | Dirk Helbing, Joachim Keltsch, Péter Molnár | Nature | 11 pp. | doi:10.1038/40353 - #GY93FG Mountain Trail Formation and the Active Walker Model - 2009 | J. P. Hague, S. J. Gilks | International Journal of Modern Physics C | 22 pp. | doi:10.1142/S0129183109014059 - #DWXKYQ Physically-based analytical erosion for fast terrain generation - 2024 | Boris Gailleton, Guillaume Cordonnier, Petros Tzathas, Philippe Steer | Computer Graphics Forum | 14 pp. | doi:10.1111/cgf.15033 - #MTDKDE Priority-Flood: An Optimal Depression-Filling and Watershed-Labeling Algorithm for Digital Elevation Models - 2014 | Clarence Lehman, David Mulla, Richard Barnes | Computers & Geosciences | 17 pp. | doi:10.1016/j.cageo.2013.04.024 - #CQBDX4 Procedural Content Generation via Machine Learning (PCGML) - 2018 | Aaron Isaksen, Adam Summerville, Amy K. Hoover, Andy Nealen, Christoffer Holmgård, Julian Togelius, Matthew Guzdial, Sam Snodgrass | IEEE Transactions on Games | 15 pp. | doi:10.1109/TG.2018.2846639 - #XDEFZS Procedural Generation of Roads - 2010 | A. Peytavie, E. Galin, E. Guérin, N. Maréchal | Computer Graphics Forum | 10 pp. | doi:10.1111/j.1467-8659.2009.01612.x - #AK7NGE Procedural Riverscapes - 2019 | A. Peytavie, B. Benes, E. Galin, E. Guérin, J. Gain, T. Dupont, Y. Cortial | Computer Graphics Forum | 12 pp. | doi:10.1111/cgf.13814 - #5MGCZ5 Real-time River Representation by Dynamic Control of Data on Waves - 2008 | Makoto Kosugi, Nobuhiko Mukai, Yasuhiro Kato | 4 pp. | doi:10.3169/itej.62.2063 - #XDESU9 Scalable real‐time animation of rivers - 2009 | Eric Bruneton, Fabrice Neyret, Nicolas Holzschuch, Qizhi Yu | Computer Graphics Forum | 11 pp. | doi:10.1111/j.1467-8659.2009.01363.x - #3XSLTA Structural Beauty: A Structure-Based Computational Approach to Quantifying the Beauty of an Image - 2021 | Bin Jiang, Chris de Rijke | Journal of Imaging | 15 pp. | doi:10.3390/jimaging7050078 - #DMTA8Y Terrain Generation Using Procedural Models Based on Hydrology - 2013 | Adrien Peytavie, Bedřich Beneš, Jean-David Génevaux, Éric Galin, Éric Guérin | ACM Transactions on Graphics | 10 pp. | doi:10.1145/2461912.2461996 - #PBM2TC Water surface wavelets - 2018 | Chris Wojtan, Matthias Müller-Fischer, Miles Macklin, Nuttapong Chentanez, Stefan Jeschke, Tomáš Skřivan | ACM Transactions on Graphics | 13 pp. | doi:10.1145/3197517.3201336 - #BYG3BQ Wholeness as a Hierarchical Graph to Capture the Nature of Space - 2015 | Bin Jiang | International Journal of Geographical Information Science | 14 pp. | doi:10.1080/13658816.2015.1038542 Book chapters (2) - #LXV9AT Principles of Trail Layout and Design - 2019 | California State Parks | California State Parks Trails Handbook | 64 pp. - #ZU8GZV Structure-Preserving Transformations - 2002 | Christopher Alexander | The Nature of Order, Book Two: The Process of Creating Life | 4 pp. | doi:10.2307/j.ctv27ftw6c.5 Reports (2) - #XW22YY Generative Codes: The Path to Building Welcoming, Beautiful, Sustainable Neighborhoods - 2005 | Brian Hanson, Christopher Alexander, Maggie Moore Alexander, Michael Mehaffy, Randall Schmidt | Center for Environmental Structure | 21 pp. - #A2QB8L Water Flow in Portal 2 - 2010 | Alex Vlachos | ACM SIGGRAPH 2010 Course: Advances in Real-Time Rendering in 3D Graphics and Games | 54 pp. Research papers (10) - #4TH488 Explainable AI for Designers: A Human-Centered Perspective on Mixed-Initiative Co-Creation - 2018 | Antonios Liapis, G. Michael Youngblood, Jichen Zhu, Rafael Bidarra, Sebastian Risi | 2018 IEEE Conference on Computational Intelligence and Games (CIG) | 8 pp. | doi:10.1109/CIG.2018.8490433 - #9NQ94D Extracting Physics from Blended Platformer Game Levels - 2020 | Adam Summerville, Anurag Sarkar, Joseph C. Osborn, Sam Snodgrass | Joint Proceedings of the AIIDE 2020 Workshops (CEUR Workshop Proceedings, Vol. 2862) | 7 pp. - #PXG56P Harmony-Seeking Computations: A Science of Non-Classical Dynamics Based on the Progressive Evolution of the Larger Whole - 2009 | Christopher Alexander | Unpublished manuscript | 66 pp. - #7GR3AQ Procedural Content Generation through Quality Diversity - 2019 | Ahmed Khalifa, Antonios Liapis, Daniele Gravina, Georgios N. Yannakakis, Julian Togelius | 2019 IEEE Conference on Games (CoG) | 8 pp. | doi:10.1109/CIG.2019.8848053 - #8SERGP Real-time Breaking Waves for Shallow Water Simulations - 2007 | Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm | 15th Pacific Conference on Computer Graphics and Applications (Pacific Graphics 2007) | 8 pp. | doi:10.1109/PG.2007.33 - #CWC7H9 Real-time Rendering of Enhanced Shallow Water Fluid Simulations - 2013 | Antonio Susín, Jesús Ojeda | Computers & Graphics | 9 pp. - #MVUJ8Z Real-time Rendering of River Networks - 2010 | Quintijn Hendrickx, Rafael Bidarra, Ruben M. Smelik | Proceedings of the ACM SIGGRAPH Symposium on Interactive 3D Graphics and Games | 1 pp. - #WZ8DHP Runtime Evaluation of Procedural Content Generation in an Endless Runner Game Using Autonomous Agents - 2026 | Rishabh Kar | arXiv | 25 pp. | doi:10.48550/arXiv.2605.01783 - #NRBMD5 Towards Friendly Mixed Initiative Procedural Content Generation: Three Pillars of Industry - 2020 | Frederic Fol Leymarie, Gorm Lai, William Latham | Proceedings of the International Conference on the Foundations of Digital Games (FDG '20) | 4 pp. | doi:10.1145/3402942.3402946 - #869NHK Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning - 2011 | Ian Parberry, Jennifer R. Alford, Mary Yingst | Proceedings of the 6th International North American Conference on Intelligent Games and Simulation (GAMEON-NA) | 7 pp. ### 6. Assistant tool calls #### Tool call: `get_document` ```json { "id": "DMTA8Y" } ``` #### Tool call: `get_document` ```json { "id": "AK7NGE" } ``` #### Tool call: `get_document` ```json { "id": "NV2YRW" } ``` #### Tool call: `get_document` ```json { "id": "B6P8L4" } ``` #### Tool call: `get_document` ```json { "id": "GY93FG" } ``` #### Tool call: `get_document` ```json { "id": "XDEFZS" } ``` #### Tool call: `get_document` ```json { "id": "BYG3BQ" } ``` #### Tool call: `get_document` ```json { "id": "MJKTBB" } ``` #### Tool call: `get_document` ```json { "id": "7GR3AQ" } ``` #### Tool call: `get_document` ```json { "id": "4TH488" } ``` #### Tool call: `get_document` ```json { "id": "XDESU9" } ``` #### Tool call: `get_document` ```json { "id": "PBM2TC" } ``` ### 7. Assistant tool calls #### Tool call: `document_import` ```json { "action": "extract", "run_id": "KYMWYA" } ``` ### 8. Tool result: get_document DOCUMENT #DMTA8Y Title: Terrain Generation Using Procedural Models Based on Hydrology Outline: - 1 #RULAFW Terrain Generation Using Procedural Models Based on Hydrology - 1.1 #F9QBNZ Abstract - 1.2 #SFQZPA 1 Introduction - 1.3 #CZMG8P 2 Related Work - 1.4 #3G9YBV 3 Algorithm Overview - 1.5 #WWSSDJ 4 River Network Generation - 1.5.1 #YQ7VH4 4.1 Initial Candidate Nodes - 1.5.2 #DBN56J 4.2 River Network Generation - 1.5.2.1 #WXUE6Z 4.2.1 Node Selection - 1.5.2.2 #VTGN6K 4.2.2 Node Expansion - 1.6 #T6FSBF 5 River Classification - 1.6.1 #TRR58W 5.1 Segmentation and Elevation of Crests - 1.6.2 #VE6H2H 5.2 Water-courses Labeling - 1.7 #UAYDMD 6 Terrain Model Generation - 1.7.1 #ASA4YQ 6.1 River Primitives Generation - 1.7.2 #FWT7FF 6.2 Terrain Primitives Generation - 1.8 #NDTMMW 7 Terrain Tree Definition - 1.9 #SZAWPC 8 Results - 1.10 #2TLVR2 9 Conclusion - 1.11 #FV8VJA References ### 9. Assistant tool calls #### Tool call: `update_document_metadata` ```json { "document_id": "9YMD2E", "micro_abstract": "BFO's bicategorial framework: SNAP snapshot ontologies of continuants and a SPAN ontology of processes in spacetime, linked by trans-ontological relations to capture change — demonstrated on the ontology of geodynamics." } ``` #### Tool call: `generate_image` ```json { "prompt": "A striking conceptual illustration for a philosophy-of-ontology paper about time and space. Split composition: the left half shows a crisp frozen snapshot of a landscape — a mountain, a river, a small city — rendered as clean three-dimensional geometric forms suspended at a single instant, like a museum diorama sliced by a luminous vertical plane of glass labeled by nothing, just light. The right half shows the very same landscape smeared into elegant four-dimensional \"worms\": the river becomes a braided translucent ribbon flowing through a stack of ghosted time-slices, the city grows and shifts through layered translucent strata, storm systems trace glowing helical trails through a deep indigo spacetime volume. Thin golden threads arc across the central glass plane, stitching objects on the frozen side to their corresponding process-ribbons on the flowing side. Style: refined scientific-romantic digital painting, deep indigo and slate palette with warm amber and gold accents, subtle grid of spacetime coordinates fading into darkness, no text, cinematic lighting, high detail." } ``` ### 10. Tool result: get_document DOCUMENT #BYG3BQ Title: Wholeness as a Hierarchical Graph to Capture the Nature of Space Outline: - 1 #V2MHRV Wholeness as a Hierarchical Graph to Capture the Nature of Space - 1.1 #QT5RF7 Abstract - 1.2 #3KT2GU 1. Introduction - 1.3 #LWK7XQ 2. The 15 properties - 1.3.1 #7DFB5R Levels of scale - 1.3.2 #VKHKZE Strong centers - 1.3.3 #ZEFTKL Thick boundaries - 1.3.4 #3ZAA2T Alternating repetition - 1.3.5 #8F5QLZ Positive space - 1.3.6 #5XAZE9 Good shape - 1.3.7 #TPHRL2 Local symmetries - 1.3.8 #HRMBT3 Deep interlock and ambiguity - 1.3.9 #KJVTM2 Contrast - 1.3.10 #ZBHUGU Gradients - 1.3.11 #CJKJCA Roughness - 1.3.12 #QBQVH3 Echoes - 1.3.13 #GWEVEN Void - 1.3.14 #CUK2M3 Simplicity and inner calm - 1.3.15 #FGVYNH Not-separateness - 1.4 #9FK8U9 3. Wholeness as a hierarchical graph - 1.4.1 #JH73PK 3.1 Measuring the degrees of life using the PageRank scores for the centers - 1.4.2 #ATC4YW 3.2 Measuring the degree of life using ht-index for the wholeness - 1.5 #TXBKLJ 4. Case studies: Computing the degrees of life - 1.5.1 #B54GRW 4.1 The plan of Alhambra - 1.5.2 #3NPEFU 4.2 The streets of Manhattan and Sweden - 1.6 #7HNVWB 5. Further discussions on the mathematical model of wholeness - 1.7 #GM64DB 6. Conclusion - 1.8 #J9877W Acknowledgment - 1.9 #WVAHUB References: ### 11. Assistant tool calls #### Tool call: `get_document` ```json { "id": "9YMD2E" } ``` ### 12. Tool result: get_document DOCUMENT #MJKTBB Title: Living Images: A Recursive Approach to Computing the Structural Beauty of Images or the Livingness of Space Outline: - 1 #YXCQD2 Living Images: A Recursive Approach to Computing the Structural Beauty of Images or the Livingness of Space - 1.1 #K2N49X Abstract - 1.2 #7WXQSD 1. Introduction - 1.3 #QF78BG 2. Living structure, the degree of structural beauty or livingness, and two laws - 1.4 #KXUAWS 3. A recursive approach to computing the structural beauty of images - 1.4.1 #LB8R59 3.1 Head/tail breaks and two laws of living structure - 1.4.2 #KK923R 3.2 The recursive approach - 1.5 #563UCF 4. Case studies - 1.5.1 #TM4DU2 4.1 Verification of the recursive approach - 1.5.2 #7V2LAA 4.2 Centroids of the substructures capture the skeleton of the images - 1.5.3 #AKW33C 4.3 Decomposable substructures and their centroids - 1.6 #266PRV 5. The livingness of space: Related work, application, and implication - 1.7 #AMFSDX 6. Conclusion - 1.8 #KNGJAN Data and code availability statement - 1.9 #BMA3YP References: - 1.10 #2KSWYX Appendix A: Verification of the recursive approach against georeferenced images ### 13. Assistant tool calls #### Tool call: `update_document_metadata` ```json { "cover_image_id": "3M6RAX", "document_id": "9YMD2E" } ``` ### 14. Tool result: get_document DOCUMENT #4TH488 Title: Explainable AI for Designers: A Human-Centered Perspective on Mixed-Initiative Co-Creation Outline: - 1 #TS8HQQ Explainable AI for Designers: A Human-Centered Perspective on Mixed-Initiative Co-Creation - 1.1 #YCT748 I. INTRODUCTION - 1.2 #2WYVSE II. RELATED WORK - 1.2.1 #TLPY7Z A. Black-Box XAI approaches - 1.2.2 #MGG2UN B. White-Box XAI approaches - 1.2.3 #P92MF3 C. Mixed-Initiative Co-Creative Systems - 1.2.4 #G9HJMX D. Measuring Explanations - 1.3 #2RSV2N III. EXPLAINING EXPLAINABILITY - 1.4 #KYV5WL IV. EXPLAINABLE AI FOR DESIGNERS (XAID) - 1.5 #N4TMHB V. MAPPING THE SPACE OF XAID - 1.5.1 #Y48SHT A. Spectrum of Explainability - 1.5.2 #ZXY6H4 B. Spectrum of Initiative - 1.5.3 #A3Q6W7 C. Spectrum of Domain Overlap - 1.6 #L7TGN5 VI. THREE USE CASES - 1.6.1 #PG7W2U A. Use Case 1: White-Box PCG System - 1.6.2 #KG32FP B. Use Case 2: Black-box PCG System - 1.6.3 #AK3WD7 C. Use Case 3: Black-box NPC Behavior System - 1.7 #8R8CBL VII. OPEN CHALLENGES - 1.7.1 #GVAXNH A. White-Box Systems - 1.7.2 #HV85DW B. Black-Box Systems - 1.7.3 #XNNY82 C. Combined approaches - 1.8 #MGUBR3 VIII. CONCLUSIONS - 1.9 #XNEDKE ACKNOWLEDGEMENTS - 1.10 #CXQ7B9 REFERENCES ### 15. Tool result: get_document DOCUMENT #XDESU9 Title: Scalable real‐time animation of rivers Outline: - 1 #Y6CNDB Scalable Real-Time Animation of Rivers - 1.1 #DHLFEL ► To cite this version: - 2 #B9LYTR Scalable real-time animation of rivers - 2.1 #RQUAEM Abstract - 2.2 #UJRUGW 1. Introduction - 2.3 #JW4T3Z 2. Previous work - 2.3.1 #CVHDLT 2.1. Fluid velocity - 2.3.2 #HEUBG3 2.2. Fluid surface - 2.4 #XF2N2Y 3. Overview - 2.4.1 #LFKVYW Algorithm 1 Scalable real-time animation of rivers - 2.5 #S3P9T2 4. Computing flow velocities - 2.5.1 #89NKTG 4.1. Finding the volumetric flow rate from the hydro geometry - 2.5.2 #R6ERAY 4.2. Interpolation of stream function - 2.5.3 #XB2KH8 4.3. Handling obstacles - 2.5.4 #TPMQZV 4.4. Fast distance calculation - 2.6 #NRD5JU 5. Adaptive texture advection - 2.6.1 #7RRTRY 5.1. Dynamic particle distribution - 2.6.1.1 #C52JGF Algorithm 2 Dynamic particle distribution - 2.6.2 #KWALBE 5.2. Sprite-based texturing - 2.6.2.1 #AL6Q7V Algorithm 3 Fragment shader for fluid meshes - 2.7 #LQXUW2 6. Implementation and results - 2.8 #TJAYJS 7. Discussion and limitations - 2.9 #RD97PY 8. Conclusion and future work - 2.10 #R6KZ4N References ### 16. Tool result: get_document DOCUMENT #PBM2TC Title: Water surface wavelets Outline: - 1 #RNVWWR Water Surface Wavelets - 1.1 #JPDLVU ACM Reference Format: - 1.2 #ZTWDW3 1 INTRODUCTION - 1.3 #MGX8HM 2 RELATED WORK - 1.3.1 #2W6Q6T 2.1 Spectrum-based approaches - 1.3.2 #SJKC5Z 2.2 Numerical solutions to Partial Differential Equations - 1.3.3 #C6S3T5 2.3 Hybrid approaches - 1.3.4 #B4G3KW 2.4 Art-directing waves - 1.4 #5EX6YK 3 THEORY - 1.4.1 #9RASZL 3.1 Motivation - 1.4.2 #ARD5T6 3.2 Derivation - 1.4.3 #UL9HZ6 3.3 Discussion - 1.5 #2KAQMF 4 DISCRETIZATION - 1.5.1 #6AJDFD 4.1 Discretizing \mathcal{A} - 1.5.2 #JGKFAU 4.2 Discretizing Advection - 1.5.3 #KQNQXW 4.3 Height field evaluation - 1.6 #MU7P6S 5 ALGORITHM SUMMARY - 1.6.1 #AJK8ET Algorithm 1 Pseudocode for the algorithms used in our paper - 1.7 #MEQNZV 6 EXTENSIONS - 1.7.1 #B6SYLX 6.1 Dissipation - 1.7.2 #5W242X 6.2 Pre-computing wave motions - 1.7.3 #UTTFQ9 6.3 Solid-Fluid Coupling - 1.8 #8LZWQ3 7 ARTISTIC CONTROL - 1.8.1 #CXPF2K 7.1 Selecting the basis function \psi(k) - 1.8.2 #AV6VHK 7.2 Manually overriding \mathcal{A} - 1.9 #AL43YK 8 RESULTS - 1.10 #W3R46F 9 DISCUSSION - 1.11 #ERWM2J ACKNOWLEDGMENTS - 1.12 #95PXLR REFERENCES - 1.13 #QXS3UP A AMPLITUDE DYNAMICS - 1.14 #FFTTEG B \mathcal{A} IS LOWER FREQUENCY THAN \eta - 1.15 #ZHSTA4 C CONTINUUM LIMIT OF WATER WAVE PACKETS ### 17. Assistant tool calls #### Tool call: `read` ```json { "blocks": [ "F9QBNZ", "VZP285", "5RMF3P", "4PR2LM", "HX4K49", "VJ7KYS", "QT5RF7", "K2N49X", "TZM794", "YCT748", "RQUAEM", "ZTWDW3" ], "expand": false } ``` ### 18. Tool result: read SECTION #F9QBNZ Document: #DMTA8Y Terrain Generation Using Procedural Models Based on Hydrology Context: #DMTA8Y Terrain Generation Using Procedural Models Based on Hydrology #RULAFW Terrain Generation Using Procedural Models Based on Hydrology #F9QBNZ Abstract Children: - #7CSK9U excerpt - We present a framework that allows quick and intuitive modeling of terrains using concepts inspired by hydrology. The terrain is generated from a simple initial sketch, and its ge… - #GE8WDB excerpt - CR Categories: I.3.5 [Computer Graphics]: Computational Geometry and Object Modeling; I.3.6 [Computer Graphics]: Methodology and Techniques—Interaction Techniques I.6.8 [Simulatio… - #4KYSN6 excerpt - Keywords: procedural modeling, terrain generation, hydrology - #5FY3UR excerpt - Links: DL PDF WEB VIDEO - #STCJQ5 excerpt - *e-mail:eric.galin@liris.cnrs.fr - #DHJ3KE excerpt - ACM Reference Format Gnevaux, J., Galin, E., Gurin, E., Peytavie, A., Bene, B. 2013. Terrain Generation Using Procedural Models based on Hydrology. ACM Trans. Graph. 32, 4,… - #G6YCHT excerpt - Copyright Notice Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or di… SECTION #VZP285 Document: #AK7NGE Procedural Riverscapes Context: #AK7NGE Procedural Riverscapes #JJE8HN Procedural Riverscapes #VZP285 Abstract Children: - #DBZ8GU excerpt - This paper addresses the problem of creating animated riverscapes through a novel procedural framework that generates the inscribing geometry of a river network and then synthesiz… SECTION #5RMF3P Document: #NV2YRW FastFlow: GPU Acceleration of Flow and Depression Routing for Landscape Simulation Context: #NV2YRW FastFlow: GPU Acceleration of Flow and Depression Routing for Landscape Simulation #6UY46T FastFlow: GPU Acceleration of Flow and Depression Routing for Landscape Simulation #5RMF3P Abstract Children: - #BKN6BV excerpt - Terrain analysis plays an important role in computer graphics, hydrology and geomorphology. In particular, analyzing the path of material flow over a terrain with consideration of… - #LS5PD7 excerpt - In this paper, we propose a novel GPU flow routing algorithm that computes the water discharge in \mathcal{O}(\log n) iterations for a terrain with n vertices (assuming n processo… SECTION #4PR2LM Document: #B6P8L4 Active walker model for the formation of human and animal trail systems Context: #B6P8L4 Active walker model for the formation of human and animal trail systems #E9C9Y2 Active Walker Model for the Formation of Human and Animal Trail Systems #4PR2LM Abstract Children: - #H2R66Q excerpt - Active walker models have recently proved their great value for describing the formation of clusters, periodic patterns, and spiral waves as well as the development of rivers, die… - #FZGBXK excerpt - Our trail formation model includes an equation of motion, an equation for environmental changes, and an orientation relation. It contains some model functions, which are specified… - #J3PYTL excerpt - #8DNZZS excerpt - #4MJ457 excerpt - #LFS7S4 excerpt - Whereas pedestrians leave footprints on the ground, ants produce chemical markings for their orientation. Nevertheless, it is more important that pedestrians steer towards a certa… - #PCL35Q excerpt - The trail formation model can be used as a tool for the optimization of pedestrian facilities: It allows urban planners to design convenient way systems which actually meet the ro… - #8CUJT6 excerpt - #LKQP8X excerpt - #5X4JB4 excerpt SECTION #HX4K49 Document: #GY93FG Mountain Trail Formation and the Active Walker Model Context: #GY93FG Mountain Trail Formation and the Active Walker Model #G4BEE9 Mountain trail formation and the active walker model #HX4K49 6. Summary Children: - #S2VCY4 excerpt - We have developed an extension to the active walker model to handle the formation of trails on inclines. Our simulations are in qualitative agreement with empirical observations o… - #WE9YUA excerpt - #2XEL3Y excerpt - #BQSVBB excerpt - The preference of walkers to take consecutive steps in the same direction could also be relevant for the understanding of trail formation in flat areas, and it is our opinion that… SECTION #VJ7KYS Document: #XDEFZS Procedural Generation of Roads Context: #XDEFZS Procedural Generation of Roads #UR2SY7 Procedural Generation of Roads #VJ7KYS Abstract Children: - #R83ZL9 excerpt - In this paper, we propose an automatic method for generating roads based on a weighted anisotropic shortest path algorithm. Given an input scene, we automatically create a path co… - #WD3XJZ excerpt - Categories and Subject Descriptors (according to ACM CCS): [Computer Graphics]: Three-Dimensional Graphics and Realism - #EFY56P excerpt - Keywords: Procedural modeling, road generation, discrete anisotropic shortest path. SECTION #QT5RF7 Document: #BYG3BQ Wholeness as a Hierarchical Graph to Capture the Nature of Space Context: #BYG3BQ Wholeness as a Hierarchical Graph to Capture the Nature of Space #V2MHRV Wholeness as a Hierarchical Graph to Capture the Nature of Space #QT5RF7 Abstract Children: - #HDXQZV excerpt - According to Christopher Alexander's theory of centers, a whole comprises numerous, recursively defined centers for things or spaces surrounding us. Wholeness is a type of global … - #EZR65U excerpt - Keywords: Centers, ht-index, head/tail breaks, big data, complexity, scaling SECTION #K2N49X Document: #MJKTBB Living Images: A Recursive Approach to Computing the Structural Beauty of Images or the Livingness of Space Context: #MJKTBB Living Images: A Recursive Approach to Computing the Structural Beauty of Images or the Livingness of Space #YXCQD2 Living Images: A Recursive Approach to Computing the Structural Beauty of Images or the Livingness of Space #K2N49X Abstract Children: - #47VNT4 excerpt - According to Gestalt theory, any image is perceived subconsciously as a coherent structure (or whole) with two contrast substructures: figure and ground. The figure consists of nu… - #NQGKKH excerpt - Keywords: Substructures, living structure, wholeness, structural beauty, head/tail breaks, livingness of space SECTION #TZM794 Document: #7GR3AQ Procedural Content Generation through Quality Diversity Context: #7GR3AQ Procedural Content Generation through Quality Diversity #DZ9GFC Procedural Content Generation through Quality Diversity #TZM794 I. INTRODUCTION Children: - #AQNL9X excerpt - Since ROGUE (Toy and Wichman, 1980) and Elite (Acornsoft, 1984) in the 1980s, certain genres of digital games have relied on algorithmic processes to generate content such as leve… - #TMBRXU excerpt - In sum, it has been established that many PCG problems require both quality and diversity of the generated content [3]. This poses a challenge for many existing PCG methods, which… - #QBCZCH excerpt - Quality-Diversity (QD) algorithms are a novel family of evolution-like algorithms that simultaneously maintain the quality and diversity of their solutions by rewarding divergence… SECTION #YCT748 Document: #4TH488 Explainable AI for Designers: A Human-Centered Perspective on Mixed-Initiative Co-Creation Context: #4TH488 Explainable AI for Designers: A Human-Centered Perspective on Mixed-Initiative Co-Creation #TS8HQQ Explainable AI for Designers: A Human-Centered Perspective on Mixed-Initiative Co-Creation #YCT748 I. INTRODUCTION Children: - #T7RH8U excerpt - With the swift development of artificial intelligence (AI) and machine learning (ML) in recent years, their applications (digital games included) have become more sophisticated. W… - #NJWGK9 excerpt - In this vision paper, we focus on one group of human users. We propose a new research area of eXplainable AI for Designers (XAID) and specifically for game designers. The increase… - #8XQUW4 excerpt - By focusing on a specific user group, their needs and tasks, we provide the basis of a human-centered XAID approach which facilitates game designers to co-create with AI/ML techni… - #LPGKEQ excerpt - and planning. We believe that, although fundamental understandings of the properties of different AI/ML techniques are essential, the goal of XAID includes investigating the actua… - #FY6X96 excerpt - Below, Section II presents related work on XAI and mixed-initiative human-AI co-creativity. We present our framework on explainability and the three axes of XAID in Sections III a… SECTION #RQUAEM Document: #XDESU9 Scalable real‐time animation of rivers Context: #XDESU9 Scalable real‐time animation of rivers #B9LYTR Scalable real-time animation of rivers #RQUAEM Abstract Children: - #3UZ7TP excerpt - Many recent games and applications target the interactive exploration of realistic large scale worlds. These worlds consist mostly of static terrain models, as the simulation of a… SECTION #ZTWDW3 Document: #PBM2TC Water surface wavelets Context: #PBM2TC Water surface wavelets #RNVWWR Water Surface Wavelets #ZTWDW3 1 INTRODUCTION Children: - #KZQGW5 excerpt - This paper concerns the efficient and physically plausible animation and art-direction of water surface waves at large scales. Current solutions to this problem invoke numerical s… - #RFLQDX excerpt - Our work proposes a novel transformation to speed up the computation of water surface waves. Instead of discretizing the wave height and momentum at each point on a grid (like pre… - #784244 excerpt - We derive new equations for propagating these local frequency dependent amplitudes through space; these equations result in simple 2D advection and diffusion operations that can b… - #XMSZWB excerpt - The contributions of our paper are: - #GJXVEJ excerpt - • Eulerian Wavelet Transformation: A new theoretical model for water wave transport based on the theory of slowly modulated waves. • Low-frequency simulation variables: Our discre… - #EMZ6QE excerpt - water height itself, so we can represent them on lower resolution grids. This change of variables allows more efficient computation and larger computational domains (Figure 1). - #BSWBFW excerpt - • Novel artistic control: In addition to determining the amplitude function using the physical equations of motion, we also experiment with overwriting these wave amplitudes for a… ### 19. Assistant You’ve got **39 sources** here: 25 journal articles, 10 conference/research papers, 2 book chapters, and 2 reports. They cluster into six main themes. ### 1. Procedural terrain, rivers, and erosion This is the technical core of the collection. - **Hydrology-based terrain generation** constructs terrain and drainage networks together, often from minimal user input (#DMTA8Y). The framework begins with a sketch and derives terrain using hydrological concepts (#7CSK9U). - **Procedural Riverscapes** goes further by generating river geometry, carving the riverbed, and synthesizing animated flow within one workflow (#AK7NGE; #DBZ8GU). - **FastFlow**, **Priority-Flood**, and the recent erosion papers focus on efficient flow routing, depression handling, watershed analysis, and landscape evolution—especially relevant for interactive generation (#NV2YRW; #BKN6BV; #MTDKDE; #DWXKYQ). - **Large Scale Terrain Generation** connects tectonic uplift with fluvial erosion (#96ZMGK). **Main question:** How can geomorphological processes become fast, controllable procedural models? ### 2. Trails, roads, and emergent paths These papers offer two contrasting ways to produce paths. - The **active walker** papers model trails as self-organizing feedback: walkers alter the environment, and those alterations influence later walkers (#B6P8L4; #H2R66Q). The mountain extension adds incline and walking biomechanics (#GY93FG; #S2VCY4). - The **road-generation** papers instead formulate path placement as optimization. Peytavie et al. use weighted anisotropic shortest paths with terrain-sensitive costs (#XDEFZS; #R83ZL9). - The trail-design handbook supplies practical constraints and terminology (#LXV9AT), while procedural street modeling covers interactive urban networks (#V4TQYB). **Main question:** Should a path be optimized directly, or emerge through repeated agent–environment interaction? ### 3. Real-time water simulation and rendering This cluster is mainly about making water visually convincing without full expensive fluid simulation. - **Scalable Real-Time Animation of Rivers**, river textures, and Lagrangian texture advection address velocity fields and moving surface detail (#XDESU9; #RQUAEM; #WZMZGY; #92XRH7). - **Water Surface Wavelets** represents waves through lower-frequency local amplitudes, improving scalability while retaining artistic control (#PBM2TC; #RFLQDX). - Other papers cover particles, shallow water, breaking waves, foam, ocean techniques, and the production-oriented *Portal 2* solution (#RBS5K6; #8SERGP; #CWC7H9; #869NHK; #C4AY2M; #A2QB8L). **Main question:** What combination of physical plausibility, scalability, and art direction is appropriate for interactive landscapes? ### 4. PCG, search, and human–AI co-creation These sources provide the broader procedural-design framework. - **PCGML** surveys content generation using learned models (#CQBDX4). - **Quality Diversity** argues that generators should return a varied collection of good solutions rather than one optimum (#7GR3AQ; #QBCZCH). - **Explainable AI for Designers** treats explanation as part of the designer’s interaction with a co-creative system, organized around explainability, initiative, and domain overlap (#4TH488; #NJWGK9). - The mixed-initiative industry paper emphasizes whether such tools are usable and acceptable in real production (#NRBMD5). - The autonomous-agent paper and platformer-physics paper concern evaluating or inferring properties of generated content (#WZ8DHP; #9NQ94D). **Main question:** How can a procedural system expose meaningful choices rather than behaving like an opaque generator? ### 5. Living structure, wholeness, and beauty This appears to be the theoretical and evaluative strand. - Alexander’s texts describe design as a sequence of **structure-preserving transformations** that progressively strengthens the larger whole (#ZU8GZV; #PXG56P). - Jiang formalizes Alexander’s “centers” as a hierarchical graph and uses measures such as PageRank and the ht-index (#BYG3BQ; #HDXQZV). - The later papers extend this into computational measures of structural beauty and image “livingness” (#3XSLTA; #MJKTBB; #47VNT4). - **Beautimeter** is the newest application, using GPT to assess architecture and urban form through Alexander’s 15 properties (#MH5J8D). - **Generative Codes** applies the same family of ideas to neighborhood-scale development (#XW22YY). **Main question:** Can the coherence or “life” of generated environments be represented computationally without reducing it to a simplistic aesthetic score? ### 6. Peripheral but potentially useful methods - Racing trajectories provide a fast two-stage trajectory-optimization analogy (#G3TBNG). - Geography’s “third view of space” supplies a broader spatial ontology (#SKRF4C). - Ocean rendering papers are useful references, although less directly tied to river and trail generation. ## Overall shape of the library The collection supports a thesis about **procedurally generating coherent landscapes through interacting processes**: 1. **Terrain and water establish environmental structure.** 2. **Walkers, trails, roads, and rivers create networks through feedback or optimization.** 3. **Real-time methods make the result interactive.** 4. **Mixed-initiative PCG gives the designer control.** 5. **Living-structure theory supplies a possible criterion for evaluating the resulting whole.** The strongest starting set is **Terrain Generation Using Procedural Models Based on Hydrology** (#DMTA8Y), **Procedural Riverscapes** (#AK7NGE), **Active Walker Model** (#B6P8L4), **Mountain Trail Formation** (#GY93FG), **Quality Diversity** (#7GR3AQ), **Explainable AI for Designers** (#4TH488), and **Wholeness as a Hierarchical Graph** (#BYG3BQ). ### 20. Tool result: get_document DOCUMENT #XDESU9 Title: Scalable real‐time animation of rivers Outline: - 1 #Y6CNDB Scalable Real-Time Animation of Rivers - 1.1 #DHLFEL ► To cite this version: - 2 #B9LYTR Scalable real-time animation of rivers - 2.1 #RQUAEM Abstract - 2.2 #UJRUGW 1. Introduction - 2.3 #JW4T3Z 2. Previous work - 2.3.1 #CVHDLT 2.1. Fluid velocity - 2.3.2 #HEUBG3 2.2. Fluid surface - 2.4 #XF2N2Y 3. Overview - 2.4.1 #LFKVYW Algorithm 1 Scalable real-time animation of rivers - 2.5 #S3P9T2 4. Computing flow velocities - 2.5.1 #89NKTG 4.1. Finding the volumetric flow rate from the hydro geometry - 2.5.2 #R6ERAY 4.2. Interpolation of stream function - 2.5.3 #XB2KH8 4.3. Handling obstacles - 2.5.4 #TPMQZV 4.4. Fast distance calculation - 2.6 #NRD5JU 5. Adaptive texture advection - 2.6.1 #7RRTRY 5.1. Dynamic particle distribution - 2.6.1.1 #C52JGF Algorithm 2 Dynamic particle distribution - 2.6.2 #KWALBE 5.2. Sprite-based texturing - 2.6.2.1 #AL6Q7V Algorithm 3 Fragment shader for fluid meshes - 2.7 #LQXUW2 6. Implementation and results - 2.8 #TJAYJS 7. Discussion and limitations - 2.9 #RD97PY 8. Conclusion and future work - 2.10 #R6KZ4N References ### 21. Tool result: get_document DOCUMENT #PBM2TC Title: Water surface wavelets Outline: - 1 #RNVWWR Water Surface Wavelets - 1.1 #JPDLVU ACM Reference Format: - 1.2 #ZTWDW3 1 INTRODUCTION - 1.3 #MGX8HM 2 RELATED WORK - 1.3.1 #2W6Q6T 2.1 Spectrum-based approaches - 1.3.2 #SJKC5Z 2.2 Numerical solutions to Partial Differential Equations - 1.3.3 #C6S3T5 2.3 Hybrid approaches - 1.3.4 #B4G3KW 2.4 Art-directing waves - 1.4 #5EX6YK 3 THEORY - 1.4.1 #9RASZL 3.1 Motivation - 1.4.2 #ARD5T6 3.2 Derivation - 1.4.3 #UL9HZ6 3.3 Discussion - 1.5 #2KAQMF 4 DISCRETIZATION - 1.5.1 #6AJDFD 4.1 Discretizing \mathcal{A} - 1.5.2 #JGKFAU 4.2 Discretizing Advection - 1.5.3 #KQNQXW 4.3 Height field evaluation - 1.6 #MU7P6S 5 ALGORITHM SUMMARY - 1.6.1 #AJK8ET Algorithm 1 Pseudocode for the algorithms used in our paper - 1.7 #MEQNZV 6 EXTENSIONS - 1.7.1 #B6SYLX 6.1 Dissipation - 1.7.2 #5W242X 6.2 Pre-computing wave motions - 1.7.3 #UTTFQ9 6.3 Solid-Fluid Coupling - 1.8 #8LZWQ3 7 ARTISTIC CONTROL - 1.8.1 #CXPF2K 7.1 Selecting the basis function \psi(k) - 1.8.2 #AV6VHK 7.2 Manually overriding \mathcal{A} - 1.9 #AL43YK 8 RESULTS - 1.10 #W3R46F 9 DISCUSSION - 1.11 #ERWM2J ACKNOWLEDGMENTS - 1.12 #95PXLR REFERENCES - 1.13 #QXS3UP A AMPLITUDE DYNAMICS - 1.14 #FFTTEG B \mathcal{A} IS LOWER FREQUENCY THAN \eta - 1.15 #ZHSTA4 C CONTINUUM LIMIT OF WATER WAVE PACKETS ### 22. Assistant tool calls #### Tool call: `read` ```json { "blocks": [ "F9QBNZ", "VZP285", "5RMF3P", "4PR2LM", "HX4K49", "VJ7KYS", "QT5RF7", "K2N49X", "TZM794", "YCT748", "RQUAEM", "ZTWDW3" ], "expand": false } ``` ### 23. Tool result: read SECTION #F9QBNZ Document: #DMTA8Y Terrain Generation Using Procedural Models Based on Hydrology Context: #DMTA8Y Terrain Generation Using Procedural Models Based on Hydrology #RULAFW Terrain Generation Using Procedural Models Based on Hydrology #F9QBNZ Abstract Children: - #7CSK9U excerpt - We present a framework that allows quick and intuitive modeling of terrains using concepts inspired by hydrology. The terrain is generated from a simple initial sketch, and its ge… - #GE8WDB excerpt - CR Categories: I.3.5 [Computer Graphics]: Computational Geometry and Object Modeling; I.3.6 [Computer Graphics]: Methodology and Techniques—Interaction Techniques I.6.8 [Simulatio… - #4KYSN6 excerpt - Keywords: procedural modeling, terrain generation, hydrology - #5FY3UR excerpt - Links: DL PDF WEB VIDEO - #STCJQ5 excerpt - *e-mail:eric.galin@liris.cnrs.fr - #DHJ3KE excerpt - ACM Reference Format Gnevaux, J., Galin, E., Gurin, E., Peytavie, A., Bene, B. 2013. Terrain Generation Using Procedural Models based on Hydrology. ACM Trans. Graph. 32, 4,… - #G6YCHT excerpt - Copyright Notice Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or di… SECTION #VZP285 Document: #AK7NGE Procedural Riverscapes Context: #AK7NGE Procedural Riverscapes #JJE8HN Procedural Riverscapes #VZP285 Abstract Children: - #DBZ8GU excerpt - This paper addresses the problem of creating animated riverscapes through a novel procedural framework that generates the inscribing geometry of a river network and then synthesiz… SECTION #5RMF3P Document: #NV2YRW FastFlow: GPU Acceleration of Flow and Depression Routing for Landscape Simulation Context: #NV2YRW FastFlow: GPU Acceleration of Flow and Depression Routing for Landscape Simulation #6UY46T FastFlow: GPU Acceleration of Flow and Depression Routing for Landscape Simulation #5RMF3P Abstract Children: - #BKN6BV excerpt - Terrain analysis plays an important role in computer graphics, hydrology and geomorphology. In particular, analyzing the path of material flow over a terrain with consideration of… - #LS5PD7 excerpt - In this paper, we propose a novel GPU flow routing algorithm that computes the water discharge in \mathcal{O}(\log n) iterations for a terrain with n vertices (assuming n processo… SECTION #4PR2LM Document: #B6P8L4 Active walker model for the formation of human and animal trail systems Context: #B6P8L4 Active walker model for the formation of human and animal trail systems #E9C9Y2 Active Walker Model for the Formation of Human and Animal Trail Systems #4PR2LM Abstract Children: - #H2R66Q excerpt - Active walker models have recently proved their great value for describing the formation of clusters, periodic patterns, and spiral waves as well as the development of rivers, die… - #FZGBXK excerpt - Our trail formation model includes an equation of motion, an equation for environmental changes, and an orientation relation. It contains some model functions, which are specified… - #J3PYTL excerpt - #8DNZZS excerpt - #4MJ457 excerpt - #LFS7S4 excerpt - Whereas pedestrians leave footprints on the ground, ants produce chemical markings for their orientation. Nevertheless, it is more important that pedestrians steer towards a certa… - #PCL35Q excerpt - The trail formation model can be used as a tool for the optimization of pedestrian facilities: It allows urban planners to design convenient way systems which actually meet the ro… - #8CUJT6 excerpt - #LKQP8X excerpt - #5X4JB4 excerpt SECTION #HX4K49 Document: #GY93FG Mountain Trail Formation and the Active Walker Model Context: #GY93FG Mountain Trail Formation and the Active Walker Model #G4BEE9 Mountain trail formation and the active walker model #HX4K49 6. Summary Children: - #S2VCY4 excerpt - We have developed an extension to the active walker model to handle the formation of trails on inclines. Our simulations are in qualitative agreement with empirical observations o… - #WE9YUA excerpt - #2XEL3Y excerpt - #BQSVBB excerpt - The preference of walkers to take consecutive steps in the same direction could also be relevant for the understanding of trail formation in flat areas, and it is our opinion that… SECTION #VJ7KYS Document: #XDEFZS Procedural Generation of Roads Context: #XDEFZS Procedural Generation of Roads #UR2SY7 Procedural Generation of Roads #VJ7KYS Abstract Children: - #R83ZL9 excerpt - In this paper, we propose an automatic method for generating roads based on a weighted anisotropic shortest path algorithm. Given an input scene, we automatically create a path co… - #WD3XJZ excerpt - Categories and Subject Descriptors (according to ACM CCS): [Computer Graphics]: Three-Dimensional Graphics and Realism - #EFY56P excerpt - Keywords: Procedural modeling, road generation, discrete anisotropic shortest path. SECTION #QT5RF7 Document: #BYG3BQ Wholeness as a Hierarchical Graph to Capture the Nature of Space Context: #BYG3BQ Wholeness as a Hierarchical Graph to Capture the Nature of Space #V2MHRV Wholeness as a Hierarchical Graph to Capture the Nature of Space #QT5RF7 Abstract Children: - #HDXQZV excerpt - According to Christopher Alexander's theory of centers, a whole comprises numerous, recursively defined centers for things or spaces surrounding us. Wholeness is a type of global … - #EZR65U excerpt - Keywords: Centers, ht-index, head/tail breaks, big data, complexity, scaling SECTION #K2N49X Document: #MJKTBB Living Images: A Recursive Approach to Computing the Structural Beauty of Images or the Livingness of Space Context: #MJKTBB Living Images: A Recursive Approach to Computing the Structural Beauty of Images or the Livingness of Space #YXCQD2 Living Images: A Recursive Approach to Computing the Structural Beauty of Images or the Livingness of Space #K2N49X Abstract Children: - #47VNT4 excerpt - According to Gestalt theory, any image is perceived subconsciously as a coherent structure (or whole) with two contrast substructures: figure and ground. The figure consists of nu… - #NQGKKH excerpt - Keywords: Substructures, living structure, wholeness, structural beauty, head/tail breaks, livingness of space SECTION #TZM794 Document: #7GR3AQ Procedural Content Generation through Quality Diversity Context: #7GR3AQ Procedural Content Generation through Quality Diversity #DZ9GFC Procedural Content Generation through Quality Diversity #TZM794 I. INTRODUCTION Children: - #AQNL9X excerpt - Since ROGUE (Toy and Wichman, 1980) and Elite (Acornsoft, 1984) in the 1980s, certain genres of digital games have relied on algorithmic processes to generate content such as leve… - #TMBRXU excerpt - In sum, it has been established that many PCG problems require both quality and diversity of the generated content [3]. This poses a challenge for many existing PCG methods, which… - #QBCZCH excerpt - Quality-Diversity (QD) algorithms are a novel family of evolution-like algorithms that simultaneously maintain the quality and diversity of their solutions by rewarding divergence… SECTION #YCT748 Document: #4TH488 Explainable AI for Designers: A Human-Centered Perspective on Mixed-Initiative Co-Creation Context: #4TH488 Explainable AI for Designers: A Human-Centered Perspective on Mixed-Initiative Co-Creation #TS8HQQ Explainable AI for Designers: A Human-Centered Perspective on Mixed-Initiative Co-Creation #YCT748 I. INTRODUCTION Children: - #T7RH8U excerpt - With the swift development of artificial intelligence (AI) and machine learning (ML) in recent years, their applications (digital games included) have become more sophisticated. W… - #NJWGK9 excerpt - In this vision paper, we focus on one group of human users. We propose a new research area of eXplainable AI for Designers (XAID) and specifically for game designers. The increase… - #8XQUW4 excerpt - By focusing on a specific user group, their needs and tasks, we provide the basis of a human-centered XAID approach which facilitates game designers to co-create with AI/ML techni… - #LPGKEQ excerpt - and planning. We believe that, although fundamental understandings of the properties of different AI/ML techniques are essential, the goal of XAID includes investigating the actua… - #FY6X96 excerpt - Below, Section II presents related work on XAI and mixed-initiative human-AI co-creativity. We present our framework on explainability and the three axes of XAID in Sections III a… SECTION #RQUAEM Document: #XDESU9 Scalable real‐time animation of rivers Context: #XDESU9 Scalable real‐time animation of rivers #B9LYTR Scalable real-time animation of rivers #RQUAEM Abstract Children: - #3UZ7TP excerpt - Many recent games and applications target the interactive exploration of realistic large scale worlds. These worlds consist mostly of static terrain models, as the simulation of a… SECTION #ZTWDW3 Document: #PBM2TC Water surface wavelets Context: #PBM2TC Water surface wavelets #RNVWWR Water Surface Wavelets #ZTWDW3 1 INTRODUCTION Children: - #KZQGW5 excerpt - This paper concerns the efficient and physically plausible animation and art-direction of water surface waves at large scales. Current solutions to this problem invoke numerical s… - #RFLQDX excerpt - Our work proposes a novel transformation to speed up the computation of water surface waves. Instead of discretizing the wave height and momentum at each point on a grid (like pre… - #784244 excerpt - We derive new equations for propagating these local frequency dependent amplitudes through space; these equations result in simple 2D advection and diffusion operations that can b… - #XMSZWB excerpt - The contributions of our paper are: - #GJXVEJ excerpt - • Eulerian Wavelet Transformation: A new theoretical model for water wave transport based on the theory of slowly modulated waves. • Low-frequency simulation variables: Our discre… - #EMZ6QE excerpt - water height itself, so we can represent them on lower resolution grids. This change of variables allows more efficient computation and larger computational domains (Figure 1). - #BSWBFW excerpt - • Novel artistic control: In addition to determining the amplitude function using the physical equations of motion, we also experiment with overwriting these wave amplitudes for a… ### 24. Assistant You’ve got **39 sources** here: 25 journal articles, 10 conference/research papers, 2 book chapters, and 2 reports. They cluster into six main themes. ### 1. Procedural terrain, rivers, and erosion This is the technical core of the collection. - **Hydrology-based terrain generation** constructs terrain and drainage networks together, often from minimal user input (#DMTA8Y). The framework begins with a sketch and derives terrain using hydrological concepts (#7CSK9U). - **Procedural Riverscapes** goes further by generating river geometry, carving the riverbed, and synthesizing animated flow within one workflow (#AK7NGE; #DBZ8GU). - **FastFlow**, **Priority-Flood**, and the recent erosion papers focus on efficient flow routing, depression handling, watershed analysis, and landscape evolution—especially relevant for interactive generation (#NV2YRW; #BKN6BV; #MTDKDE; #DWXKYQ). - **Large Scale Terrain Generation** connects tectonic uplift with fluvial erosion (#96ZMGK). **Main question:** How can geomorphological processes become fast, controllable procedural models? ### 2. Trails, roads, and emergent paths These papers offer two contrasting ways to produce paths. - The **active walker** papers model trails as self-organizing feedback: walkers alter the environment, and those alterations influence later walkers (#B6P8L4; #H2R66Q). The mountain extension adds incline and walking biomechanics (#GY93FG; #S2VCY4). - The **road-generation** papers instead formulate path placement as optimization. Peytavie et al. use weighted anisotropic shortest paths with terrain-sensitive costs (#XDEFZS; #R83ZL9). - The trail-design handbook supplies practical constraints and terminology (#LXV9AT), while procedural street modeling covers interactive urban networks (#V4TQYB). **Main question:** Should a path be optimized directly, or emerge through repeated agent–environment interaction? ### 3. Real-time water simulation and rendering This cluster is mainly about making water visually convincing without full expensive fluid simulation. - **Scalable Real-Time Animation of Rivers**, river textures, and Lagrangian texture advection address velocity fields and moving surface detail (#XDESU9; #RQUAEM; #WZMZGY; #92XRH7). - **Water Surface Wavelets** represents waves through lower-frequency local amplitudes, improving scalability while retaining artistic control (#PBM2TC; #RFLQDX). - Other papers cover particles, shallow water, breaking waves, foam, ocean techniques, and the production-oriented *Portal 2* solution (#RBS5K6; #8SERGP; #CWC7H9; #869NHK; #C4AY2M; #A2QB8L). **Main question:** What combination of physical plausibility, scalability, and art direction is appropriate for interactive landscapes? ### 4. PCG, search, and human–AI co-creation These sources provide the broader procedural-design framework. - **PCGML** surveys content generation using learned models (#CQBDX4). - **Quality Diversity** argues that generators should return a varied collection of good solutions rather than one optimum (#7GR3AQ; #QBCZCH). - **Explainable AI for Designers** treats explanation as part of the designer’s interaction with a co-creative system, organized around explainability, initiative, and domain overlap (#4TH488; #NJWGK9). - The mixed-initiative industry paper emphasizes whether such tools are usable and acceptable in real production (#NRBMD5). - The autonomous-agent paper and platformer-physics paper concern evaluating or inferring properties of generated content (#WZ8DHP; #9NQ94D). **Main question:** How can a procedural system expose meaningful choices rather than behaving like an opaque generator? ### 5. Living structure, wholeness, and beauty This appears to be the theoretical and evaluative strand. - Alexander’s texts describe design as a sequence of **structure-preserving transformations** that progressively strengthens the larger whole (#ZU8GZV; #PXG56P). - Jiang formalizes Alexander’s “centers” as a hierarchical graph and uses measures such as PageRank and the ht-index (#BYG3BQ; #HDXQZV). - The later papers extend this into computational measures of structural beauty and image “livingness” (#3XSLTA; #MJKTBB; #47VNT4). - **Beautimeter** is the newest application, using GPT to assess architecture and urban form through Alexander’s 15 properties (#MH5J8D). - **Generative Codes** applies the same family of ideas to neighborhood-scale development (#XW22YY). **Main question:** Can the coherence or “life” of generated environments be represented computationally without reducing it to a simplistic aesthetic score? ### 6. Peripheral but potentially useful methods - Racing trajectories provide a fast two-stage trajectory-optimization analogy (#G3TBNG). - Geography’s “third view of space” supplies a broader spatial ontology (#SKRF4C). - Ocean rendering papers are useful references, although less directly tied to river and trail generation. ## Overall shape of the library The collection supports a thesis about **procedurally generating coherent landscapes through interacting processes**: 1. **Terrain and water establish environmental structure.** 2. **Walkers, trails, roads, and rivers create networks through feedback or optimization.** 3. **Real-time methods make the result interactive.** 4. **Mixed-initiative PCG gives the designer control.** 5. **Living-structure theory supplies a possible criterion for evaluating the resulting whole.** The strongest starting set is **Terrain Generation Using Procedural Models Based on Hydrology** (#DMTA8Y), **Procedural Riverscapes** (#AK7NGE), **Active Walker Model** (#B6P8L4), **Mountain Trail Formation** (#GY93FG), **Quality Diversity** (#7GR3AQ), **Explainable AI for Designers** (#4TH488), and **Wholeness as a Hierarchical Graph** (#BYG3BQ). ### 25. User I'm pretty sure that, in human experience and animal experience, the world that I experience, the environment that I experience, is actually procedurally generated, in a sense. Isn't that more or less true? I don't see the details of reality even when I look closely at a close-up. I'm sitting at a desk now that I built out of birch plywood. On that desk is a mouse pad that I made out of granulated cork board and some acrylic lacquer, and I chamfered the edges with sandpaper a bit, etc. The plywood, I didn't really put any kind of finish on, so it has quite a lot of dirt and random discolorations. I'm pretty sure that my experience even of this cork pattern, as I'm looking at it directly right now from 10 cm, is kind of invented by my brain. I think that's one thing that psychedelic, like LSD, makes relatively blatant: the mind and our perceptual system are incredibly, incredibly extraordinarily good at fabricating detailed textures and patterns that are never quite the same. You never look at the same river twice. You never even look at the same piece of wood twice. ### 26. Assistant tool calls #### Tool call: `search_text` ```json { "limit": 10, "query": "breaking waves shoreline shore splash spray foam" } ``` #### Tool call: `search_text` ```json { "limit": 10, "query": "volumetric water particles splashes" } ``` #### Tool call: `search_text` ```json { "limit": 10, "query": "shallow water simulation real-time breaking waves" } ``` #### Tool call: `search_text` ```json { "limit": 10, "query": "foam rendering real time" } ``` #### Tool call: `search_text` ```json { "limit": 10, "query": "shoreline wave animation coastal" } ``` ### 27. Tool result: search_text Exact matches 1. Source: Water-rendering literature overview (#4CB2WQ) Matching note #4CB2WQ: The water-rendering corpus organizes around a recurring hybrid strategy: simulate only the low-frequency/structural behavior needed for motion, then add high-frequency visual detail and optical cues cheaply. The survey separates deep-water parametric/spectral methods from shallow-water fluid methods and identifies foam, spray, and light interaction as separate realism layers (#4S5XNT, #CZNWCP). River methods use coarse or procedural velocity fields plus advected wave textures: Arnold et al. combine 2D Navier–Stokes, hydrostatic pressure columns, and texture advection (#8KBMFE, #T9Y2PR); Yu et al. compute local steady flow and use screen-space sampled wave sprites for huge terrains (#3UZ7TP, #AL6YQ9); their later Lagrangian texture-advection method uses deformable particle grids to preserve both flow and texture spectrum (#DZCPD6, #KSH8JS). Vlachos's Portal 2 production method is the cheapest end of this continuum: artist-authored flow maps distort two normal-map layers, with offsets and noise hiding repetition/pulsing (#6ELMAT, #XVFV3N). Shallow-water work adds effects a height field cannot express: Thürey et al. detect steep fronts and spawn connected-particle sheets for overturning waves, drops, and foam (#KHRCTA, #XFKY8Q); Ojeda and Susín layer FFT/noise normals, advected foam, photon caustics, and screen-space reflection/refraction over a shallow-water simulation (#BVUXWL, #PBZNNB). Scherzer et al. target fully dynamic particle fluids, using screen-space depth/thickness layers, adaptive curvature-flow smoothing, and Weber-number-based volumetric foam (#G3TYUA, #YJNSYU). Surface Wavelets is the strongest large-scale wave paper: it simulates slowly varying amplitudes over space/frequency/direction on a coarse grid, reconstructs detailed waves separately, supports obstacles and artistic control, and runs a 4 km × 4 km scene at 60 fps (#RFLQDX, #764D8D, #WKY9MT); it cannot handle breaking waves or splashes because it is linear (#YWWZAM). Specialized cheap methods include halftone-mask foam dissipation with under 3% overhead (#KFWVK3, #V5XDSY), Bézier-curve river networks with streaming normal maps (#QGESFA, #MSQQ8G), and distance-dependent switching among Stokes, cosine, and bump-mapped wave models (#H2E2UR, #EYM9N6). 2. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 0 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #J39ZBT 1 Introduction Matching excerpt #Q726HQ: ing of waves at the shore line can, however, not be captured with such a reduced model. We propose a new technique to enhance efficient height field liquid simulation with particle based sheets, in order to create the effect of breaking waves. As a breaking wave is a highly turbulent process that is still not fully understood, we do not aim to fully simulate this phenomenon in real-time, but to capture its most important visual features. 3. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 1 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #LSRGTK 2 Related Work Matching excerpt #XYKATD: Full 3D simulations became popular with the methods developed in [19] and [4], and have by now been extended in numerous ways. Studies of breaking waves have likewise first been performed in 2D [1]. [16] on the other hand presented a full 3D treatment of breaking waves with a Volume-of-Fluid simulation. In [20] the visual impact of breaking waves has been improved by adding particles for sprays and foam. Similar to [16], an approach to use slices of 2D simulations for wave simulations in real-time is demonstrated in [23]. Recently, Full three-dimensional simulations have been combined with two-dimensional techniques to speed up simulations of large volumes. In [9], a 2D simulation is performed beneath a layer of full 3D simulation for the fluid surface, while [22] couple the 3D simulation region to a 2D shallow water simulation. While these approaches significantly lower the simulation time, they are still not suitable for real-time applications. 4. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 0 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #47WJV5 Abstract Matching excerpt #4S5XNT: This paper presents a survey of ocean simulation and rendering methods in computer graphics. To model and animate the ocean's surface, these methods mainly rely on two main approaches: on the one hand, those which approximate ocean dynamics with parametric, spectral or hybrid models and use empirical laws from oceanographic research. We will see that this type of methods essentially allows the simulation of ocean scenes in the deep water domain, without breaking waves. On the other hand, physically-based methods use Navier-Stokes Equations (NSE) to represent breaking waves and more generally ocean surface near the shore. We also describe ocean rendering methods in computer graphics, with a special interest in the simulation of phenomena such as foam and spray, and light's interaction with the ocean surface. 5. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 9 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #8TWR84 4. Realistic ocean surface rendering and lighting #UKRC7P 4.1. Foam and spray #7DVESV 4.1.2. Particle systems Matching excerpt #732756: Peachey [Pea86] first proposed to use particle systems in order to represent spray generated by breaking waves. Wang et al [WZC*06] extend this approach by describing breaking waves using a Lagrangian approach, and generating spray subsystems according to the velocity of water particles (see Figure 9). Holmberg and Wunsche [HW04] generate foam particles by considering the amplitude of the waves, and render them as cloud points. The same idea is used by other authors [JG01, JBS03, CC06] to generate spray particles according to the temporal variation of height at a given point. 6. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 12 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #4KX5BA 5. Conclusion Matching excerpt #CZNWCP: The first two sections of our survey focused on computer graphics models able to simulate the dynamical behavior of the ocean. We have seen that those methods are divided into two categories: on the one hand, methods usually dedicated to deep-water simulation, on the other hand fluid-based approaches trying to represent breaking waves near the shore. In the last section, we have seen different methods able to represent several phenomena involved in ocean rendering, namely foam, sprays and light-water interactions, that make for visual realism. 7. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 2 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #JPY4VD 2. Ocean dynamics simulation in deep water #B9SCHY 2.1. Spatial domain approaches #3VTQEF 2.1.1. Early works Matching excerpt #5ZZ3T3: The same idea was developed with a simple bump mapping approach, where normal vectors on a planar mesh are transformed using a sum of 20 cycloids [Sch80]. However, assuming that the bottom of the sea is at infinite depth limits the use of these methods since they don't include more complex phenomena such as breaking waves or waves refraction near the shore. Peachey [Pea86] introduces a depth parameter to compute the wave vector k_i of each wave, using Airy wave theory: 8. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 5 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #JPY4VD 2. Ocean dynamics simulation in deep water #VEG3CE 2.4. Discussion Matching excerpt #5BKCH7: However, all these methods only consider deep water phenomena, in which the ocean surface is being subjected to small perturbations. Indeed, in shallow water parametric or spectral approaches cannot faithfully reproduce ocean dynamics near coasts, e.g. breaking waves. To address this complexity, we have to focus on approaches that consider interactions and collisions between the ocean and the shore, which are presented in the next section. 9. Source: Real-time Rendering of Enhanced Shallow Water Fluid Simulations (#CWC7H9), Antonio Susín, Jesús Ojeda, p. 2 Context: #3XLN3C Real-time Rendering of Enhanced Shallow Water Fluid Simulations #D9SXF3 1. Introduction #RNG4NC 1.1. Related Work #XEPFKX 179 3.2. Surface Foam Matching excerpt #E47KSP: 180 In the real life situation where splashes are generated, like 181 in breaking waves, it is most probable that foam is generated 182 when these splashes hit the fluid bulk again. 10. Source: Recommended water renderer for procedural hydrological terrain (#JVRSKS) Matching note #JVRSKS: For a game with precomputed geological erosion and hydrology, the best fit is a stylized data-driven hybrid rather than runtime CFD. Reuse channel topology, banks, flow direction, discharge/drainage area, slope, depth/width, curvature, drops, junctions, obstacles, and distance-to-shore as shader/control fields. This closely matches the input assumed by scalable river animation (#QXYWAJ) and Procedural Riverscapes, which derives per-cell slope, volume, and velocity (#X3RVN8) and selects calm, turbulent, wave, cascade, vortex, and ripple primitives from terrain and flow conditions (#GU2NEL, #5NJY7V). Recommended architecture: one shared water material; rivers use generated flow maps to advect two offset normal/detail layers as in Portal 2 (#6ELMAT, #XVFV3N); lakes use low-speed wind ripples and shoreline masks; ocean uses a few art-directed Gerstner/spectral bands plus shore foam. Generate masks for turbulence/foam from normalized stream power, slope, curvature, constriction, drops, and obstacles; use depth for color/opacity and shallow-ground blending; use local feature primitives only at visually important events such as waterfalls, rapids, confluences, and rocks. Apply screen- or distance-dependent LOD, retaining flow direction and wind at distance while removing displacement and local effects (#H2E2UR, #EYM9N6). Approximate matches 1. Source: Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning (#869NHK), Ian Parberry, Jennifer R. Alford, Mary Yingst, p. 1 Context: #5R6DEX Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning #L9YLTY Introduction Score: 0.023 Related excerpt #EP8V8T: Real ocean foam consists of bubbles clumped together by surface tension on the surface of the water. Foam does not simply fade or become transparent as the bubbles dissipate. Traditional methods of foam generation ignore the active nature of foam density where bubbles pop over time. Since surface bubbles are either present or not in an area of water, this binary nature lends itself to the use of halftoning, a process used to reproduce images using patterns of black dots. Our use of halftoning with a saturation function that changes over time causes 2. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 4 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #8ES8PA 6 Rendering the Waves Score: 0.025 Related excerpt #N8F4SP: Finally, to give the impression of a larger scale, we use standard particles. These are generated when the particles of the wave patch hit the shallow water surface. Moreover, particles are spawned along the tip of the wave patch. Here, in reality, the drag of the air causes disturbances of the fluid sheet, resulting in the formation of drops. For the pictures shown in this paper, we furthermore use a small scale bump map to distort the reflective shallow water surface, which gives the impression of smaller surface waves. 3. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 0 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #J39ZBT 1 Introduction Score: 0.024 Related excerpt #Q726HQ: ing of waves at the shore line can, however, not be captured with such a reduced model. We propose a new technique to enhance efficient height field liquid simulation with particle based sheets, in order to create the effect of breaking waves. As a breaking wave is a highly turbulent process that is still not fully understood, we do not aim to fully simulate this phenomenon in real-time, but to capture its most important visual features. 4. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 2 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #PHN7AY 4 Wave Simulation Score: 0.024 Related excerpt #744R83: Detection: Typically, a wave breaks when an initially smooth wave approaches a region of shallow water, e.g., a beach. The decreased height of the water causes the braking influence of the ground to become stronger. The wave steepens, and, at some point, overturns. Especially at beaches this effect is reinforced by the backward current of previous waves, causing a stronger difference between the forward movement of higher fluid layers, and the slower (or backward) movement of fluid layers near the ground. 5. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 9 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #8TWR84 4. Realistic ocean surface rendering and lighting #UKRC7P 4.1. Foam and spray #7DVESV 4.1.2. Particle systems Score: 0.028 Related excerpt #732756: Peachey [Pea86] first proposed to use particle systems in order to represent spray generated by breaking waves. Wang et al [WZC*06] extend this approach by describing breaking waves using a Lagrangian approach, and generating spray subsystems according to the velocity of water particles (see Figure 9). Holmberg and Wunsche [HW04] generate foam particles by considering the amplitude of the waves, and render them as cloud points. The same idea is used by other authors [JG01, JBS03, CC06] to generate spray particles according to the temporal variation of height at a given point. 6. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 12 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #8TWR84 4. Realistic ocean surface rendering and lighting #D7BME4 4.3. Discussion Score: 0.026 Related excerpt #9UVK2R: Numerous methods are available in the literature to take different optical phenomena into account and increase the realism of oceanic scenes. In the case of foam and sprays, empirical methods can effectively simulate these phenomena according to the state of disturbance of the surface. Combined with particle systems, these approaches allow to obtain realistic details, however they require a large number of particles which induces an important memory cost and computation time at rendering stage. Moreover, empirical methods are usually efficient for deep water scenes only; to our knowledge there is no work dealing with realistic foam created by breaking waves. 7. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 9 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #8TWR84 4. Realistic ocean surface rendering and lighting #UKRC7P 4.1. Foam and spray #KCB376 4.1.1. Empirical models Score: 0.024 Related excerpt #NG5NPU: Jensen and Goliás [JG01] compute the amount of foam at a given point according to its height: if the height difference with its neighbors is greater than a predefined threshold, foam is generated and rendered using a semi-transparent texture (see Figure 8). This method was extended by Jeschke et al [JBS03] to take into account the amplitude of ocean waves. The main drawback with this approach is encountered when trying to animate foam, since its motion does not follow the waves. Another problem arises from the empirical models that do not consider atmospheric conditions which are, in reality, the main cause of the apparition of foam. Oceanographic observations have shown for example that foam only appears when wind velocity exceeds 13km/h [Mun47]. 8. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 9 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #8TWR84 4. Realistic ocean surface rendering and lighting Score: 0.023 Related excerpt #QRPHDF: In the previous sections we presented different approaches to obtain a plausible shape of the ocean surface, in deep water or near the shoreline. This surface can then be rendered using water shaders implementing light reflection and refraction described by Fresnel equations. Nevertheless, the ocean's visual aspect is characterized by numerous interactions. Their impact is visible through several phenomena such as foam, sprays and light interactions, addressed by several methods in computer graphics. Some of them were already mentioned earlier, when the fluid simulation algorithm includes these phenomena directly ( e.g. bubbles). However in most cases rendering is performed in a post-processing step. We focus on the following on different methods designed to enhance the realism of ocean scenes. 9. Source: Real-time Rendering of Enhanced Shallow Water Fluid Simulations (#CWC7H9), Antonio Susín, Jesús Ojeda, p. 2 Context: #3XLN3C Real-time Rendering of Enhanced Shallow Water Fluid Simulations #D9SXF3 1. Introduction #RNG4NC 1.1. Related Work #XEPFKX 179 3.2. Surface Foam Score: 0.03 Related excerpt #E47KSP: 180 In the real life situation where splashes are generated, like 181 in breaking waves, it is most probable that foam is generated 182 when these splashes hit the fluid bulk again. 10. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 4 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #Z68DF9 5. Real-Time Foam #P6BSN6 5.2. Layer Creation Score: 0.025 Related excerpt #LSFXLY: By using two water layers, one in front and one behind the foam layer, we can simulate foam inside water, as happens at the end of a waterfall (see for instance Figure 8, middle or Figure 5). We first determine the front water surface and the front foam surface by splatting water and foam particles into separate depth buffers (the splatting step was described in Section 4). Curvature flow is only applied to the front water surface. ### 28. Tool result: get_document DOCUMENT #LXV9AT Title: Untitled thesis Outline: - 1 #XRDH78 Figures - 2 #P3P37A Photos - 3 #HE95FY Chapter 5. Principles of Trail Layout and Design - 3.1 #92S5AZ 5.1. Life of a Trail - 3.2 #QB5YWT 5.2. Elements of a Good Trail - 3.3 #4DMRYZ 5.3. Identification of Need - 3.4 #JZHJ8Q 5.4. Identification of Trail Use Types, Classifications, and Design Standards - 3.5 #BUKYGV 5.5. Mechanical Wear - 3.5.1 #V5SGUS 5.5.1. Identification of Mechanical Wear by Use Type - 3.5.1.1 #U4N4Q8 5.5.1.1. Hardness and Shape of User Surface. - 3.5.1.2 #MBW44W 5.5.1.2. User Weight and Surface Contact Area - 3.5.1.3 #LR2Y76 5.5.1.3. Velocity, Angle of Impingement, and Coefficient of Kinetic Friction - 3.5.1.4 #PEUZYA 5.5.1.4. Acceleration, Braking, and Turning/Curving - 3.5.1.4.1 #YE7XWW 5.5.1.4.1. Pedestrians - 3.5.1.4.2 #W4PRY2 5.5.1.4.2. Equestrians - 3.5.1.4.3 #73D857 5.5.1.4.3. Mountain Bikers - 3.5.1.4.4 #XLMSSL 5.5.1.4.4. Off Highway Vehicles - 3.5.2 #FG5UFB 5.5.2. Linear Mechanical Wear - 3.5.3 #UGJ3ZE 5.5.3. Vertical Point Depression Features - 3.5.4 #8BXTCV 5.5.4. Sudden Grade Changes - 3.5.5 #SUVWGE 5.5.5. Parent Soil Strength and Durability - 3.5.6 #RQKELJ 5.5.1. Natural Erosion - 3.5.6.1 #MCFMJS 5.5.1.1. Water - 3.5.6.2 #AVSTPC 5.5.1.2. Wind - 3.5.6.3 #GKGP2X 5.5.1.3. Mechanical Wear and Natural Erosion - 3.5.7 #KN98KH 5.5.2. Categories of Mechanical Wear - 3.5.7.1 #W33EV6 5.5.2.1. Low Mechanical Wear - 3.5.7.1.1 #WA59GU Trail design, construction, and management techniques for low mechanical wear include: - 3.5.7.2 #R28ZKS 5.5.2.2. Moderate Mechanical Wear - 3.5.7.2.1 #EGEBBG Trail design, construction, and management techniques for moderate mechanical wear include: - 3.5.7.3 #BXPQJ9 5.5.2.3. Heavy Mechanical Wear - 3.5.7.3.1 #RZ9JXT Trail design, construction, and management techniques for heavy mechanical wear include: - 3.5.8 #YNAMST 5.5.3. Comparative Mechanical Wear Rankings - 3.6 #M2FCT4 5.6. Maintaining Natural Drainage - 3.7 #EEPQMJ 5.7. Trail Layout - 3.7.1 #7XTB8T 5.7.1. Review of Existing Information - 3.7.2 #D9NVQC 5.7.2. Major Control Points and Average Linear Grades - 3.7.3 #XSQ2CN 5.7.3. Maximum Sustainable Linear Grades - 3.7.3.1 #2YGFFK 5.7.3.1. Soil Strength and Durability - 3.7.3.2 #ZFYZXZ 5.7.3.2. Annual Rainfall - 3.7.3.3 #74WYLZ 5.7.3.3. Rainfall Intensity - 3.7.3.4 #Y3XWQH 5.7.3.4. Canopy Cover - 3.7.3.5 #7FRMWX 5.7.3.5. Percent of Hillslope - 3.7.3.6 #SB9AAG 5.7.3.6. Location on the Hillslope - 3.7.3.7 #VGA57R 5.7.3.7. Season of Use - 3.7.3.8 #DQ4WG4 5.7.3.8. Evaluation of Existing Trails - 3.7.3.9 #BRLU95 5.7.3.9. Evaluating and Interpreting the Criteria - 3.7.4 #ZGJXBS 5.7.4. Designed Linear Grades - 3.7.5 #9WNHGK 5.7.5. Field Reconnaissance - 3.7.5.1 #7JBFFE 5.7.5.1. Minor Control Point Identification - 3.7.5.1.1 #4U7TV6 TRAIL LAYOUT AND DESIGN - 3.7.5.2 #XG25M6 5.7.5.2. Designed Control Points - 3.7.5.2.1 #XDF6ZN 5.7.5.2.1. Watercourse Crossings - 3.7.5.2.2 #9EED3X 5.7.5.2.2. Turns - 3.7.5.2.3 #W2A9QZ 5.7.5.2.3. Topographic Control Points - 3.7.5.2.4 #UM24VH 5.7.5.2.4. Problematic Topography - 3.7.5.2.5 #AG3WMA 5.7.5.2.5. Orientation/Aspect - 3.7.6 #NQEU6U 5.7.6. Final Grade Reconciliation - 3.7.7 #8BZAPC 5.7.7. Flagging the Trail Alignment - 3.7.7.1 #AGRR47 5.7.7.1. Initial Flagging Process - 3.7.7.1.1 #K2KA8X LEVELING EXERCISE - 3.7.7.1.2 #CRJ2SY SHOOTING GRADE - 3.7.7.1.3 #ADY5XK CLINOMETER - 3.7.7.1.4 #SKHQPC SIGHTING FOR GRADE WITH CLINOMETER - 3.7.7.1.5 #A8QPLC TRAVELWAY EXCAVATIONS - 3.7.7.2 #P4ZHEP 5.7.7.2. Second Flagging of the Alignment - 3.8 #W8FRQE 5.8. Developing Trail Work Logs and Cost Estimates ### 29. Tool result: get_document DOCUMENT #UYLTYJ Title: Untitled thesis Outline: - 1 #BSSYS2 Modelling the Evolution of Human Trail Systems - 2 #NTZWM2 REFERENCES - 2.1 #25JSQ6 ACKNOWLEDGMENTS - 2.2 #5LE8NQ FIGURES ### 30. Tool result: search_text Exact matches 1. Source: Water-rendering literature overview (#4CB2WQ) Matching note #4CB2WQ: The water-rendering corpus organizes around a recurring hybrid strategy: simulate only the low-frequency/structural behavior needed for motion, then add high-frequency visual detail and optical cues cheaply. The survey separates deep-water parametric/spectral methods from shallow-water fluid methods and identifies foam, spray, and light interaction as separate realism layers (#4S5XNT, #CZNWCP). River methods use coarse or procedural velocity fields plus advected wave textures: Arnold et al. combine 2D Navier–Stokes, hydrostatic pressure columns, and texture advection (#8KBMFE, #T9Y2PR); Yu et al. compute local steady flow and use screen-space sampled wave sprites for huge terrains (#3UZ7TP, #AL6YQ9); their later Lagrangian texture-advection method uses deformable particle grids to preserve both flow and texture spectrum (#DZCPD6, #KSH8JS). Vlachos's Portal 2 production method is the cheapest end of this continuum: artist-authored flow maps distort two normal-map layers, with offsets and noise hiding repetition/pulsing (#6ELMAT, #XVFV3N). Shallow-water work adds effects a height field cannot express: Thürey et al. detect steep fronts and spawn connected-particle sheets for overturning waves, drops, and foam (#KHRCTA, #XFKY8Q); Ojeda and Susín layer FFT/noise normals, advected foam, photon caustics, and screen-space reflection/refraction over a shallow-water simulation (#BVUXWL, #PBZNNB). Scherzer et al. target fully dynamic particle fluids, using screen-space depth/thickness layers, adaptive curvature-flow smoothing, and Weber-number-based volumetric foam (#G3TYUA, #YJNSYU). Surface Wavelets is the strongest large-scale wave paper: it simulates slowly varying amplitudes over space/frequency/direction on a coarse grid, reconstructs detailed waves separately, supports obstacles and artistic control, and runs a 4 km × 4 km scene at 60 fps (#RFLQDX, #764D8D, #WKY9MT); it cannot handle breaking waves or splashes because it is linear (#YWWZAM). Specialized cheap methods include halftone-mask foam dissipation with under 3% overhead (#KFWVK3, #V5XDSY), Bézier-curve river networks with streaming normal maps (#QGESFA, #MSQQ8G), and distance-dependent switching among Stokes, cosine, and bump-mapped wave models (#H2E2UR, #EYM9N6). 2. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 1 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #LSRGTK 2 Related Work Matching excerpt #CX9SXN: Two-dimensional water simulations based on height fields offer more flexibility while keeping computational cost low. The capabilities of a simplified shallow water discretization for computer graphics were first presented in [11]. Furthermore, [17] extended a shallow water simulation with particle based splashes. [5] and [2] cover the basics of floating objects on the water surface. More recent work on shallow water simulations for real-time applications can be found in [12], where the authors apply noise textures for increased surface details, or [7] and [15], where wave simulations using the GPU are demonstrated. 3. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 4 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #8ES8PA 6 Rendering the Waves Matching excerpt #N8F4SP: Finally, to give the impression of a larger scale, we use standard particles. These are generated when the particles of the wave patch hit the shallow water surface. Moreover, particles are spawned along the tip of the wave patch. Here, in reality, the drag of the air causes disturbances of the fluid sheet, resulting in the formation of drops. For the pictures shown in this paper, we furthermore use a small scale bump map to distort the reflective shallow water surface, which gives the impression of smaller surface waves. 4. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 8 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #XKG89F 3. Ocean dynamics simulation in shallow water #ZEVP5C 3.3. Hybrid approaches Matching excerpt #7Y38J3: Kim et al [KCC + 06] extend an adaptive level-set approach [LGF04] to generate particles according to the temporal variation of the volume of fluid in each cell. The main idea consists in using particles advected below the surface, transformed into water or air at the rendering stage. Since the number of transformed particles depends on the volume of water lost in a cell, this characterizes the turbulence in that cell and hence generates particles in highly perturbed regions. 5. Source: Real-time Rendering of Enhanced Shallow Water Fluid Simulations (#CWC7H9), Antonio Susín, Jesús Ojeda, p. 6 Context: #3XLN3C Real-time Rendering of Enhanced Shallow Water Fluid Simulations #GKHL8Q 6. Results and Discussion Matching excerpt #D98XHG: Finally, the particles have just been rendered as billboards using depth and normal replacement with a sphere model. As they represent splashes, we want to maintain their crisp representation so, to improve their appeal, some additional tweaking could be done as applying some noise to their normals or deforming them in the direction they are moving to simulate some motion blur. 6. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 3 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #Z68DF9 5. Real-Time Foam Matching excerpt #BB9PDK: In order to capture these two main effects in a real-time setting, we separate foam particles from water particles and arrange the resulting foam and water particles in separate layers and render them using volumetric back-to-front compositing. Although our layered representation does not account for discontinuity in the fluid volume which occurs if there are several layers of water and foam, the two most common cases mentioned above are covered by this model. 7. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 0 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #KGMBXL Abstract Matching excerpt #G3TYUA: We present a physically based real-time water simulation and rendering method that brings volumetric foam to the real-time domain, significantly increasing the realism of dynamic fluids. We do this by combining a particle-based fluid model that is capable of accounting for the formation of foam with a layered rendering approach that is able to account for the volumetric properties of water and foam. Foam formation is simulated through Weber number thresholding. For rendering, we approximate the resulting water and foam volumes by storing their respective boundary surfaces in depth maps. This allows us to calculate the attenuation of light rays that pass through these volumes very efficiently. We also introduce an adaptive curvature flow filter that produces consistent fluid surfaces from particles independent of the viewing distance. 8. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 4 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #Z68DF9 5. Real-Time Foam #P6BSN6 5.2. Layer Creation Matching excerpt #72YLNM: Since water and foam are volumetric phenomena, the amount of water respectively foam between two layer surfaces needs to be determined in order to allow correct compositing and attenuation. Similar to [vdLS09], the thickness of a layer is determined by additively splatting every particle belonging to the volume into a buffer. In contrast to the depth surface calculation, the splat kernel gives the thickness of the particle at each particle sampling point. Accumulating particle thicknesses is a reasonable approximation because particles from the physics simulation can be assumed to be largely non-overlapping. 9. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 1 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #JZMDNB 2. Previous Work Matching excerpt #U52B8U: Offline methods include effects like foam, bubbles and spray, and we adapt some of their elements for our real-time method. Losasso et al. [LTKF08] mix the Eulerian and Lagrangian approaches to generate realistic fluids including spray and foam. Mihalef et al. [MMS09] adapt this method and replace the Lagrangian SPH approach by a simple particle system to include droplets and bubbles. The so-called Weber number, as defined in [Sir99], is used to control the generation of droplets and bubbles, which we adapt for creating foam in real time. Takahashi et al. [TFK*03] use a particle-based approach to model splashes and foam. The generation and transition of foam is controlled using state change rules, which work in a similar way as our separation of the particles into water- and foam-particles. Cleary et 10. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 3 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #Z68DF9 5. Real-Time Foam #T4PBCD 5.1. Foam Formation Matching excerpt #YHGLZR: where \rho is the density, v is the relative velocity between the liquid and the surrounding gas, l is the characteristic length, and \sigma is the surface tension. For larger We , the kinetic energy of the water is greater than the surface energy, causing water to intermix with the surrounding air, which results in foam formation. Thus, we separate particles into water and foam particles by thresholding the Weber number. In practice, we use a linear transition area where the particle is counted both as water and foam particle to ensure a smooth emergence and disappearance of foam. The new foam particle starts out as a point and expands, while the corresponding water particle shrinks. Approximate matches 1. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 4 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #8ES8PA 6 Rendering the Waves Score: 0.028 Related excerpt #N8F4SP: Finally, to give the impression of a larger scale, we use standard particles. These are generated when the particles of the wave patch hit the shallow water surface. Moreover, particles are spawned along the tip of the wave patch. Here, in reality, the drag of the air causes disturbances of the fluid sheet, resulting in the formation of drops. For the pictures shown in this paper, we furthermore use a small scale bump map to distort the reflective shallow water surface, which gives the impression of smaller surface waves. 2. Source: Real-time Rendering of Enhanced Shallow Water Fluid Simulations (#CWC7H9), Antonio Susín, Jesús Ojeda, p. 6 Context: #3XLN3C Real-time Rendering of Enhanced Shallow Water Fluid Simulations #GKHL8Q 6. Results and Discussion Score: 0.022 Related excerpt #D98XHG: Finally, the particles have just been rendered as billboards using depth and normal replacement with a sphere model. As they represent splashes, we want to maintain their crisp representation so, to improve their appeal, some additional tweaking could be done as applying some noise to their normals or deforming them in the direction they are moving to simulate some motion blur. 3. Source: Real-time Rendering of Enhanced Shallow Water Fluid Simulations (#CWC7H9), Antonio Susín, Jesús Ojeda, p. 4 Context: #3XLN3C Real-time Rendering of Enhanced Shallow Water Fluid Simulations #5GWRQA 4. Photon-based Caustics Score: 0.021 Related excerpt #JAEGZA: 256 Gaussian splat, and their intensity is regulated depending on 257 how they are facing the light and the distance they have trav- 258 elled through the fluid until finally hit the receiving surface. At 259 last, they are blended to the contents of the framebuffer. 4. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 4 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #Z68DF9 5. Real-Time Foam #P6BSN6 5.2. Layer Creation Score: 0.029 Related excerpt #72YLNM: Since water and foam are volumetric phenomena, the amount of water respectively foam between two layer surfaces needs to be determined in order to allow correct compositing and attenuation. Similar to [vdLS09], the thickness of a layer is determined by additively splatting every particle belonging to the volume into a buffer. In contrast to the depth surface calculation, the splat kernel gives the thickness of the particle at each particle sampling point. Accumulating particle thicknesses is a reasonable approximation because particles from the physics simulation can be assumed to be largely non-overlapping. 5. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 2 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #34V9L7 4. Adaptive Curvature Flow Score: 0.029 Related excerpt #8PQTK5: The first step in rendering a fluid using particles is to create the fluid surface. This is done by splatting the particles 6. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 4 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #Z68DF9 5. Real-Time Foam #P6BSN6 5.2. Layer Creation Score: 0.027 Related excerpt #LSFXLY: By using two water layers, one in front and one behind the foam layer, we can simulate foam inside water, as happens at the end of a waterfall (see for instance Figure 8, middle or Figure 5). We first determine the front water surface and the front foam surface by splatting water and foam particles into separate depth buffers (the splatting step was described in Section 4). Curvature flow is only applied to the front water surface. 7. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 2 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #VR4JRQ 3. Overview Score: 0.026 Related excerpt #VLHP44: The original algorithm calculates the water depth by splatting the particles, then smooths the depth buffer using curvature flow filtering, then calculates water thickness by accumulating particle depths in a separate thickness buffer, and finally composites the results. Our algorithm extends this by adapting the curvature flow filter for the viewer distance, and by adding a foam layer that can lie between two water layers. Our algorithm then performs the following steps once per frame after the scene has been rendered into a texture (see Figure 3): 8. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 1 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #JZMDNB 2. Previous Work Score: 0.023 Related excerpt #9F2MSC: van der Laan et al. [vdLGS09] present an approach for rendering particle-based fluids directly using splatting instead of performing a polygonization. They use screen space curvature flow filtering to conceal the sphere geometry of the particles and to prevent the fluid from looking jelly-like. However, the curvature flow filtering is dependent on the view distance, and the proposed simple noise-based surface foam effect does not have a volumetric appearance (see Figure 1). 9. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 1 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #JZMDNB 2. Previous Work Score: 0.023 Related excerpt #U52B8U: Offline methods include effects like foam, bubbles and spray, and we adapt some of their elements for our real-time method. Losasso et al. [LTKF08] mix the Eulerian and Lagrangian approaches to generate realistic fluids including spray and foam. Mihalef et al. [MMS09] adapt this method and replace the Lagrangian SPH approach by a simple particle system to include droplets and bubbles. The so-called Weber number, as defined in [Sir99], is used to control the generation of droplets and bubbles, which we adapt for creating foam in real time. Takahashi et al. [TFK*03] use a particle-based approach to model splashes and foam. The generation and transition of foam is controlled using state change rules, which work in a similar way as our separation of the particles into water- and foam-particles. Cleary et 10. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 0 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #9QMYPL 1. Introduction Score: 0.021 Related excerpt #K9T2QM: Dynamic fluids are a desirable element of many real-time applications like games. So far, the mathematical complexity of realistically simulating and rendering the behavior and interaction of fluids with the environment has hindered their widespread use. One promising approach would be to render the results of smoothed particle hydrodynamics (SPH) simulations using splatting, but the locally high curvature of spherical splatting primitives results in an unrealistic jelly-like appearance. ### 31. Assistant tool calls #### Tool call: `search_text` ```json { "document_id": "GY93FG", "limit": 10, "query": "Mountain trail formation active walker model authors arXiv" } ``` #### Tool call: `search_text` ```json { "document_id": "LXV9AT", "limit": 10, "query": "California State Parks Trails Handbook Chapter 5 Principles Trail Layout Design date" } ``` #### Tool call: `search_text` ```json { "document_id": "UYLTYJ", "limit": 10, "query": "Modelling Evolution Human Trail Systems Dirk Helbing Joachim Keltsch Peter Molnar" } ``` #### Tool call: `search_text` ```json { "document_id": "B6P8L4", "limit": 10, "query": "Active walker model formation human animal trail systems authors DOI" } ``` ### 32. Tool result: search_text Exact matches 1. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 1 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #LSRGTK 2 Related Work Matching excerpt #XYKATD: Full 3D simulations became popular with the methods developed in [19] and [4], and have by now been extended in numerous ways. Studies of breaking waves have likewise first been performed in 2D [1]. [16] on the other hand presented a full 3D treatment of breaking waves with a Volume-of-Fluid simulation. In [20] the visual impact of breaking waves has been improved by adding particles for sprays and foam. Similar to [16], an approach to use slices of 2D simulations for wave simulations in real-time is demonstrated in [23]. Recently, Full three-dimensional simulations have been combined with two-dimensional techniques to speed up simulations of large volumes. In [9], a 2D simulation is performed beneath a layer of full 3D simulation for the fluid surface, while [22] couple the 3D simulation region to a 2D shallow water simulation. While these approaches significantly lower the simulation time, they are still not suitable for real-time applications. 2. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 6 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #QQ7TWA 9 Conclusions Matching excerpt #XFKY8Q: We have presented a new method to perform real-time simulations of open water scenes with breaking waves. It is based on detecting and tracking the wave front with line segments. The breaking wave itself is represented by a patch of connected particles. Our model for coupling a rigid body simulation with the shallow water simulation moreover makes it possible to create interesting interactive applications, and can handle cases such as submerged bodies. Overall, the algorithm performs with high frame rates, and without causing noticeable slowdowns during the course of the simulation. It furthermore allows the efficient and seamless creation of a textured surface mesh. These properties of the algorithm make it especially interesting and suitable to be used in computer games. Although it is aimed for real-time applications, the algorithm is also interesting for high quality off-line animations. It could, e.g., allow the efficient simulation of large open water shore scenes, while giving animators real-time feedback during their work. 3. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 0 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #XUY95Y Abstract Matching excerpt #KHRCTA: We present a new method for enhancing shallow water simulations by the effect of overturning waves. While full 3D fluid simulations can capture the process of wave breaking, this is beyond the capabilities of a pure height field model. 3D simulations, however, are still too expensive for real-time applications, especially when large bodies of water need to be simulated. The extension we propose overcomes this problem and makes it possible to simulate scenes such as waves near a beach, and surf riding characters in real-time. In a first step, steep wave fronts in the height field are detected and marked by line segments. These segments then spawn sheets of fluid represented by connected particles. When the sheets impinge on the water surface, they are absorbed and result in the creation of particles representing drops and foam. To enable interesting applications, we furthermore present a two-way coupling of rigid bodies with the fluid simulation. The capabilities and efficiency of the method will be demonstrated with several scenes, which run in real-time on today's commodity hardware. 4. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 6 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #CC4RWZ 8 Results Matching excerpt #Q3HMFJ: A simulation of a breaking wave at a submerged shelf is shown in Figure 7. Test cases with a submerged shelf are common in coastal engineering, and represent the typical topology of a shore area. A simulation of a breaking wave at a submerged shelf in 3D was demonstrated in, e.g., [3]. With our algorithm we can recreate this phenomenon in real-time. Here, an initially smooth wave, that would not break on even ground, is approaching the submerged shelf. The decreasing fluid height causes the wave to steepen within the shallow water framework. Eventually, the wave is steep enough to fulfill Equation (4), and triggers the creation of a breaking wave. Note that the shelf is not fully aligned with the simulation grid, which causes the wave to start breaking further towards the viewer. 5. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 1 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #LSRGTK 2 Related Work Matching excerpt #28D29F: Breaking waves have been simulated in the context of various computational fluid models. In the following we present a method for extending height field based simulations, such that the motion of breaking of waves can be computed. In particular, we will focus on shallow water simulations, as they yield a full velocity field for the fluid surface. In contrast to the spectral methods, they can, on the other hand, not handle the wave dispersion of deep water waves. It is, however, possible to apply our method to other simulation models that yield a height field and velocity vectors at the surface. Our simulation algorithm consists of the following steps: first, a normal shallow water sim- 6. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 6 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #CC4RWZ 8 Results Matching excerpt #TAFHNN: A limitation of our approach is that it doesn't properly handle cases with chaotic waves in the shallow water simulation. This causes the detected breaking waves to be removed before they can fully develop. Thus, the algorithm is not suitable for handling situations that would require many small splashes or drops, but targeted towards larger entities like a whole wave. Likewise, small scale waves caused by 7. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 1 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #LSRGTK 2 Related Work Matching excerpt #CX9SXN: Two-dimensional water simulations based on height fields offer more flexibility while keeping computational cost low. The capabilities of a simplified shallow water discretization for computer graphics were first presented in [11]. Furthermore, [17] extended a shallow water simulation with particle based splashes. [5] and [2] cover the basics of floating objects on the water surface. More recent work on shallow water simulations for real-time applications can be found in [12], where the authors apply noise textures for increased surface details, or [7] and [15], where wave simulations using the GPU are demonstrated. 8. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 0 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #J39ZBT 1 Introduction Matching excerpt #2S99TP: Our approach consists of the following steps: the detection of potentially overturning wave regions, the generation of a fluid sheet to represent the wave, its advection and, finally, the coalescence with the 2D water surface. We represent the breaking wave with connected particles, which allows for the efficient and seamless creation of a surface mesh for rendering. In order to allow further interaction of the fluid with the environment, we apply two-way coupling of the shallow water simulation with rigid bodies. The capabilities of our method will be demonstrated with several test cases, from simple setups of single waves to more realistic environments such as breaking waves at a submerged shelf, or waves generated by rigid body interaction. 9. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 0 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #J39ZBT 1 Introduction Matching excerpt #Q726HQ: ing of waves at the shore line can, however, not be captured with such a reduced model. We propose a new technique to enhance efficient height field liquid simulation with particle based sheets, in order to create the effect of breaking waves. As a breaking wave is a highly turbulent process that is still not fully understood, we do not aim to fully simulate this phenomenon in real-time, but to capture its most important visual features. 10. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 3 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #PHN7AY 4 Wave Simulation Matching excerpt #TZXE4F: However, for the interactive applications that we are targeting, the shallow water simulation can be distorted by a variety of factors, e.g., rigid bodies (as explained below) or other breaking waves. To accurately track the front of a shallow water wave with wave line \mathcal{L} , we combine an advection with the wave velocity, and a projection along the gradient direction onto the line of the steepest gradient on the wave front. The projection is performed with the bisection method, and an initial step size of length c . Usually, 2-4 steps suffice to find the desired target point. Approximate matches 1. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 6 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #QQ7TWA 9 Conclusions Score: 0.028 Related excerpt #XFKY8Q: We have presented a new method to perform real-time simulations of open water scenes with breaking waves. It is based on detecting and tracking the wave front with line segments. The breaking wave itself is represented by a patch of connected particles. Our model for coupling a rigid body simulation with the shallow water simulation moreover makes it possible to create interesting interactive applications, and can handle cases such as submerged bodies. Overall, the algorithm performs with high frame rates, and without causing noticeable slowdowns during the course of the simulation. It furthermore allows the efficient and seamless creation of a textured surface mesh. These properties of the algorithm make it especially interesting and suitable to be used in computer games. Although it is aimed for real-time applications, the algorithm is also interesting for high quality off-line animations. It could, e.g., allow the efficient simulation of large open water shore scenes, while giving animators real-time feedback during their work. 2. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 6 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #CC4RWZ 8 Results Score: 0.026 Related excerpt #Q3HMFJ: A simulation of a breaking wave at a submerged shelf is shown in Figure 7. Test cases with a submerged shelf are common in coastal engineering, and represent the typical topology of a shore area. A simulation of a breaking wave at a submerged shelf in 3D was demonstrated in, e.g., [3]. With our algorithm we can recreate this phenomenon in real-time. Here, an initially smooth wave, that would not break on even ground, is approaching the submerged shelf. The decreasing fluid height causes the wave to steepen within the shallow water framework. Eventually, the wave is steep enough to fulfill Equation (4), and triggers the creation of a breaking wave. Note that the shelf is not fully aligned with the simulation grid, which causes the wave to start breaking further towards the viewer. 3. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 1 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #LSRGTK 2 Related Work Score: 0.025 Related excerpt #28D29F: Breaking waves have been simulated in the context of various computational fluid models. In the following we present a method for extending height field based simulations, such that the motion of breaking of waves can be computed. In particular, we will focus on shallow water simulations, as they yield a full velocity field for the fluid surface. In contrast to the spectral methods, they can, on the other hand, not handle the wave dispersion of deep water waves. It is, however, possible to apply our method to other simulation models that yield a height field and velocity vectors at the surface. Our simulation algorithm consists of the following steps: first, a normal shallow water sim- 4. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 0 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #J39ZBT 1 Introduction Score: 0.023 Related excerpt #2S99TP: Our approach consists of the following steps: the detection of potentially overturning wave regions, the generation of a fluid sheet to represent the wave, its advection and, finally, the coalescence with the 2D water surface. We represent the breaking wave with connected particles, which allows for the efficient and seamless creation of a surface mesh for rendering. In order to allow further interaction of the fluid with the environment, we apply two-way coupling of the shallow water simulation with rigid bodies. The capabilities of our method will be demonstrated with several test cases, from simple setups of single waves to more realistic environments such as breaking waves at a submerged shelf, or waves generated by rigid body interaction. 5. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 1 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #LSRGTK 2 Related Work Score: 0.023 Related excerpt #XYKATD: Full 3D simulations became popular with the methods developed in [19] and [4], and have by now been extended in numerous ways. Studies of breaking waves have likewise first been performed in 2D [1]. [16] on the other hand presented a full 3D treatment of breaking waves with a Volume-of-Fluid simulation. In [20] the visual impact of breaking waves has been improved by adding particles for sprays and foam. Similar to [16], an approach to use slices of 2D simulations for wave simulations in real-time is demonstrated in [23]. Recently, Full three-dimensional simulations have been combined with two-dimensional techniques to speed up simulations of large volumes. In [9], a 2D simulation is performed beneath a layer of full 3D simulation for the fluid surface, while [22] couple the 3D simulation region to a 2D shallow water simulation. While these approaches significantly lower the simulation time, they are still not suitable for real-time applications. 6. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 0 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #J39ZBT 1 Introduction Score: 0.022 Related excerpt #Q726HQ: ing of waves at the shore line can, however, not be captured with such a reduced model. We propose a new technique to enhance efficient height field liquid simulation with particle based sheets, in order to create the effect of breaking waves. As a breaking wave is a highly turbulent process that is still not fully understood, we do not aim to fully simulate this phenomenon in real-time, but to capture its most important visual features. 7. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 6 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #CC4RWZ 8 Results Score: 0.022 Related excerpt #TZ9UQA: moving objects, can only be simulated with breaking if they are properly represented within the shallow water simulation. 8. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 0 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #XUY95Y Abstract Score: 0.022 Related excerpt #KHRCTA: We present a new method for enhancing shallow water simulations by the effect of overturning waves. While full 3D fluid simulations can capture the process of wave breaking, this is beyond the capabilities of a pure height field model. 3D simulations, however, are still too expensive for real-time applications, especially when large bodies of water need to be simulated. The extension we propose overcomes this problem and makes it possible to simulate scenes such as waves near a beach, and surf riding characters in real-time. In a first step, steep wave fronts in the height field are detected and marked by line segments. These segments then spawn sheets of fluid represented by connected particles. When the sheets impinge on the water surface, they are absorbed and result in the creation of particles representing drops and foam. To enable interesting applications, we furthermore present a two-way coupling of rigid bodies with the fluid simulation. The capabilities and efficiency of the method will be demonstrated with several scenes, which run in real-time on today's commodity hardware. 9. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 1 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #LSRGTK 2 Related Work Score: 0.022 Related excerpt #CX9SXN: Two-dimensional water simulations based on height fields offer more flexibility while keeping computational cost low. The capabilities of a simplified shallow water discretization for computer graphics were first presented in [11]. Furthermore, [17] extended a shallow water simulation with particle based splashes. [5] and [2] cover the basics of floating objects on the water surface. More recent work on shallow water simulations for real-time applications can be found in [12], where the authors apply noise textures for increased surface details, or [7] and [15], where wave simulations using the GPU are demonstrated. 10. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 2 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #PHN7AY 4 Wave Simulation Score: 0.02 Related excerpt #4DZ999: The following section will describe our approach to simulate breaking waves within the shallow water framework. We detect lines of steep wave fronts, and track these with a robust advection scheme. These wave lines generate patches of connected particles representing the fluid of an actual breaking wave. The wave lines adaptively track the original wave, and can merge with others in their neighborhood. An overview of our approach is shown in Figure 2. ### 33. Tool result: search_text Exact matches 1. Source: Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning (#869NHK), Ian Parberry, Jennifer R. Alford, Mary Yingst, p. 1 Context: #5R6DEX Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning #L9YLTY Introduction Matching excerpt #XM3XNV: Real-time animation and rendering of ocean waves is often seen in video games, and adding foam to the waves lends an added level of realism. We describe a fast and effective method for rendering ocean wave foam by augmenting traditional texture based foam saturation methods with techniques from halftoning. 2. Source: Real-time Rendering of Enhanced Shallow Water Fluid Simulations (#CWC7H9), Antonio Susín, Jesús Ojeda, p. 0 Context: #3XLN3C Real-time Rendering of Enhanced Shallow Water Fluid Simulations #SDDXFP Abstract Matching excerpt #BVUXWL: The visualization of simulated fluids is critical to understand their motion, with certain light effects restricted or with added computational complexity in the implementation if real-time simulation is required. We propose some techniques that improve the rendering quality of an enhanced shallow waters simulation. To improve the overall appeal of the fluid representation, lower scale details are added to the fluid, coupling external non-physical simulations, and advecting generated surface foam. We simulate caustics by raytracing photons in light and screen-space, and apply refraction and reflections also in screen-space, through a number of render passes. Finally, it is shown how a reasonably sized fluid simulation is executed and rendered at interactive framerates with consumer-level hardware. 3. Source: Real-time Rendering of Enhanced Shallow Water Fluid Simulations (#CWC7H9), Antonio Susín, Jesús Ojeda, p. 0 Context: #3XLN3C Real-time Rendering of Enhanced Shallow Water Fluid Simulations #SDDXFP Abstract Matching excerpt #7CK2EH: Keywords: real-time reflections and refractions, real-time caustics, fluid rendering 4. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 0 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #KGMBXL Abstract Matching excerpt #G3TYUA: We present a physically based real-time water simulation and rendering method that brings volumetric foam to the real-time domain, significantly increasing the realism of dynamic fluids. We do this by combining a particle-based fluid model that is capable of accounting for the formation of foam with a layered rendering approach that is able to account for the volumetric properties of water and foam. Foam formation is simulated through Weber number thresholding. For rendering, we approximate the resulting water and foam volumes by storing their respective boundary surfaces in depth maps. This allows us to calculate the attenuation of light rays that pass through these volumes very efficiently. We also introduce an adaptive curvature flow filter that produces consistent fluid surfaces from particles independent of the viewing distance. 5. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 3 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #Z68DF9 5. Real-Time Foam Matching excerpt #HJEP9N: In this section we describe how to incorporate foam into real-time fluid rendering. We define water foam as a substance that is formed by trapping air bubbles in the liquid. Foam is usually observed as spray or bubbles above the surface of a turbulent water stream. However, we also observed that a significant visual effect is caused by foam that occurs behind a water surface, usually due to a turbulent water stream that immerses into resting water with high impact (see Figure 5). 6. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 5 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #JEPXQL 7. Conclusions and Future Work Matching excerpt #YJNSYU: We presented a new method for rendering particle-based fluids with foam in real time. The first contribution is an adaptive curvature flow smoothing method that avoids over- or under-smoothing as present in previous methods. Our second contribution is a fast physically guided foam rendering algorithm based on Weber number thresholding and a layered compositing algorithm. Our approach provides more realistic fluid rendering at comparable cost to previous methods, and is simple to implement and integrate into existing engines. In future work, we plan to use the volumetric information available in the layers to generate soft shadows. We will also investigate whether situations that require more than 3 layers are likely to appear. 7. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 1 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #JZMDNB 2. Previous Work Matching excerpt #R4ZPDC: Current real-time approaches are usually limited in the number of particles they can handle, and do not include realistic foam [MCG03]. One way to render the water surface from the results of the particle simulation are Müller et al.'s [MSD07] screen space meshes , created using a marching squares technique on the particle depth map. Although the algorithm provides view-dependent level of detail and filtering in screen space, rendering foam with this approach is prohibitive, because of the large amount of geometry that needs to be generated. Thürey et al. [TSS*07] present a shallow water-based particle model that is coupled with a SPH simulation to simulate bubbles and foam effects, but the method simulates individual foam particles, which is expensive. 8. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 1 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #JZMDNB 2. Previous Work Matching excerpt #U52B8U: Offline methods include effects like foam, bubbles and spray, and we adapt some of their elements for our real-time method. Losasso et al. [LTKF08] mix the Eulerian and Lagrangian approaches to generate realistic fluids including spray and foam. Mihalef et al. [MMS09] adapt this method and replace the Lagrangian SPH approach by a simple particle system to include droplets and bubbles. The so-called Weber number, as defined in [Sir99], is used to control the generation of droplets and bubbles, which we adapt for creating foam in real time. Takahashi et al. [TFK*03] use a particle-based approach to model splashes and foam. The generation and transition of foam is controlled using state change rules, which work in a similar way as our separation of the particles into water- and foam-particles. Cleary et 9. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 5 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #T8YYAV 6. Results Matching excerpt #XNX9B9: shows the benefit of our physically guided foam generation over simple noise-based foam [vdLGS09]. Figure 7 demonstrates that foam is an important visual element when rendering fluids. Figure 9 compares a photograph of a real waterfall with our method. As one can observe, the foam is visible below the surface when a turbulent water stream immerges into resting water. Dynamic visual results can be observed in the accompanying video. 10. Source: Advected river textures (#WZMZGY), Dirk Arnold, Stephen Brooks, Tim Burrell, p. 0 Context: #JCB5RE Advected river textures Matching excerpt #VPL9P5: We present a new method for the realistic real-time simulation of rivers. Our solution includes a 2D fluid solver that simulates the flow of a river's surface, an efficient method for adaptively computing 3D flow information and an animated 3D procedural wave texture that is advected through the fluid via advection particles in order to mimic the highly detailed fluid surfaces that are characteristic of rivers. Our technique that couples animated texture advection with a pseudo-3D fluid simulation produces stable results that are representative of large-scale real-world rivers and suitable for use in real-time applications. Our system surpasses prior work on real-time river rendering both with regards to efficiency and visual quality, which we establish through the rendering of rivers tens of kilometers long. Copyright © 2009 John Wiley & Sons, Ltd. Approximate matches 1. Source: Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning (#869NHK), Ian Parberry, Jennifer R. Alford, Mary Yingst, p. 1 Context: #5R6DEX Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning #L9YLTY Introduction Score: 0.025 Related excerpt #XM3XNV: Real-time animation and rendering of ocean waves is often seen in video games, and adding foam to the waves lends an added level of realism. We describe a fast and effective method for rendering ocean wave foam by augmenting traditional texture based foam saturation methods with techniques from halftoning. 2. Source: Real-time Rendering of Enhanced Shallow Water Fluid Simulations (#CWC7H9), Antonio Susín, Jesús Ojeda, p. 6 Context: #3XLN3C Real-time Rendering of Enhanced Shallow Water Fluid Simulations #XHMJUD 7. Conclusions Score: 0.026 Related excerpt #R75U5V: Additionally we have applied foam and lower-scale detail by applying textures to the fluid mesh; techniques which are very low demanding in comparison to the previous ones and really help to enhance the final result. 3. Source: Real-time Rendering of Enhanced Shallow Water Fluid Simulations (#CWC7H9), Antonio Susín, Jesús Ojeda, p. 0 Context: #3XLN3C Real-time Rendering of Enhanced Shallow Water Fluid Simulations #SDDXFP Abstract Score: 0.026 Related excerpt #BVUXWL: The visualization of simulated fluids is critical to understand their motion, with certain light effects restricted or with added computational complexity in the implementation if real-time simulation is required. We propose some techniques that improve the rendering quality of an enhanced shallow waters simulation. To improve the overall appeal of the fluid representation, lower scale details are added to the fluid, coupling external non-physical simulations, and advecting generated surface foam. We simulate caustics by raytracing photons in light and screen-space, and apply refraction and reflections also in screen-space, through a number of render passes. Finally, it is shown how a reasonably sized fluid simulation is executed and rendered at interactive framerates with consumer-level hardware. 4. Source: Real-time Rendering of Enhanced Shallow Water Fluid Simulations (#CWC7H9), Antonio Susín, Jesús Ojeda, p. 6 Context: #3XLN3C Real-time Rendering of Enhanced Shallow Water Fluid Simulations #GKHL8Q 6. Results and Discussion Score: 0.023 Related excerpt #GE3XGA: The foam simulation from [2] could solve the fixed-size texture restrictions of our current solution, as they simulate foam directly with advected diffuse disks on the fluid surface, although this comes at the additional cost of generating and maintaining these disks on the fly. An alternative we believe would help our foam simulation is the use of a pyramidal texture approach; when particles fall to the fluid they initialize the correct level of the pyramid, being the other levels initialized extrapolating from that one. 5. Source: Real-time Rendering of Enhanced Shallow Water Fluid Simulations (#CWC7H9), Antonio Susín, Jesús Ojeda, p. 6 Context: #3XLN3C Real-time Rendering of Enhanced Shallow Water Fluid Simulations #GKHL8Q 6. Results and Discussion Score: 0.023 Related excerpt #P6Z6YL: Nevertheless, the timing results for both these techniques combined, the lower scale detail and the foam advection, never exceed the 2ms mark. 6. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 0 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #KGMBXL Abstract Score: 0.028 Related excerpt #G3TYUA: We present a physically based real-time water simulation and rendering method that brings volumetric foam to the real-time domain, significantly increasing the realism of dynamic fluids. We do this by combining a particle-based fluid model that is capable of accounting for the formation of foam with a layered rendering approach that is able to account for the volumetric properties of water and foam. Foam formation is simulated through Weber number thresholding. For rendering, we approximate the resulting water and foam volumes by storing their respective boundary surfaces in depth maps. This allows us to calculate the attenuation of light rays that pass through these volumes very efficiently. We also introduce an adaptive curvature flow filter that produces consistent fluid surfaces from particles independent of the viewing distance. 7. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 3 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #Z68DF9 5. Real-Time Foam Score: 0.028 Related excerpt #HJEP9N: In this section we describe how to incorporate foam into real-time fluid rendering. We define water foam as a substance that is formed by trapping air bubbles in the liquid. Foam is usually observed as spray or bubbles above the surface of a turbulent water stream. However, we also observed that a significant visual effect is caused by foam that occurs behind a water surface, usually due to a turbulent water stream that immerses into resting water with high impact (see Figure 5). 8. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 1 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #JZMDNB 2. Previous Work Score: 0.028 Related excerpt #R4ZPDC: Current real-time approaches are usually limited in the number of particles they can handle, and do not include realistic foam [MCG03]. One way to render the water surface from the results of the particle simulation are Müller et al.'s [MSD07] screen space meshes , created using a marching squares technique on the particle depth map. Although the algorithm provides view-dependent level of detail and filtering in screen space, rendering foam with this approach is prohibitive, because of the large amount of geometry that needs to be generated. Thürey et al. [TSS*07] present a shallow water-based particle model that is coupled with a SPH simulation to simulate bubbles and foam effects, but the method simulates individual foam particles, which is expensive. 9. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 5 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #JEPXQL 7. Conclusions and Future Work Score: 0.027 Related excerpt #YJNSYU: We presented a new method for rendering particle-based fluids with foam in real time. The first contribution is an adaptive curvature flow smoothing method that avoids over- or under-smoothing as present in previous methods. Our second contribution is a fast physically guided foam rendering algorithm based on Weber number thresholding and a layered compositing algorithm. Our approach provides more realistic fluid rendering at comparable cost to previous methods, and is simple to implement and integrate into existing engines. In future work, we plan to use the volumetric information available in the layers to generate soft shadows. We will also investigate whether situations that require more than 3 layers are likely to appear. 10. Source: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water (#RBS5K6), Daniel Scherzer, Florian Bagar, Michael Wimmer, p. 0 Context: #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water #9QMYPL 1. Introduction Score: 0.024 Related excerpt #HU5QE8: the undesirable spherical particle structure. Second, there exists as yet no realistic real-time method to create foam, which is an important visual element in most situations where real-time fluids are used (see Figure 1). ### 34. Tool result: search_text Exact matches 1. Source: Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning (#869NHK), Ian Parberry, Jennifer R. Alford, Mary Yingst, p. 1 Context: #5R6DEX Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning #L9YLTY Introduction Matching excerpt #XM3XNV: Real-time animation and rendering of ocean waves is often seen in video games, and adding foam to the waves lends an added level of realism. We describe a fast and effective method for rendering ocean wave foam by augmenting traditional texture based foam saturation methods with techniques from halftoning. 2. Source: Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning (#869NHK), Ian Parberry, Jennifer R. Alford, Mary Yingst, p. 5 Context: #5R6DEX Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning #LP9TTY Results Matching excerpt #RMEZSJ: Still pictures such as shown in Figure 7 and Figure 8 do not adequately capture the full effect of our algorithm. Figure 9 shows how foam bubbles fade and pop over time in the wake of each wave. This can be seen to best advantage in an animation such as the one we have placed online at [10]. 3. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 6 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #CC4RWZ 8 Results Matching excerpt #Q3HMFJ: A simulation of a breaking wave at a submerged shelf is shown in Figure 7. Test cases with a submerged shelf are common in coastal engineering, and represent the typical topology of a shore area. A simulation of a breaking wave at a submerged shelf in 3D was demonstrated in, e.g., [3]. With our algorithm we can recreate this phenomenon in real-time. Here, an initially smooth wave, that would not break on even ground, is approaching the submerged shelf. The decreasing fluid height causes the wave to steepen within the shallow water framework. Eventually, the wave is steep enough to fulfill Equation (4), and triggers the creation of a breaking wave. Note that the shelf is not fully aligned with the simulation grid, which causes the wave to start breaking further towards the viewer. 4. Source: Procedural Riverscapes (#AK7NGE), A. Peytavie, B. Benes, E. Galin, E. Guérin, J. Gain, T. Dupont, Y. Cortial, p. 6 Context: #JJE8HN Procedural Riverscapes #9ZYJP2 6. Animated Procedural River Model #U6BTCY 6.1. Riverflow Primitives Matching excerpt #GU2NEL: We have implemented a range of procedural primitives with characteristic dynamics (Figure 16), namely: calm, turbulent, wave, cascade, vortex, and ripple primitives (see the accompanying video for their animation). Calm water primitives are generated in regions with low turbulence and produce only swells and damped ripples. In contrast, turbulent water primitives are created where the water is agitated and the velocity high. Wave primitives approximate local crests and troughs, often dictated by the riverbed topography. Cascade primitives represent a more extreme version of this effect and include a corresponding plunge pool. Vortex primitives produce swirling that typically occurs downstream of under-water obstacles, such as rocks. Finally, ripples capture high frequency disturbance of the water surface from crosswinds and other sources. We also designed particular primitives for specific effects, such as echoing water ripples that approximate the complex movement of water interacting with river banks. By design it is easy to code new waterflow primitives for inclusion in the blend-flow tree. 5. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 2 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #JPY4VD 2. Ocean dynamics simulation in deep water #B9SCHY 2.1. Spatial domain approaches #3VTQEF 2.1.1. Early works Matching excerpt #FQB3R8: Gonzato and Le Saec [GS99] modify this model when the starting point of a plunging breaking wave is detected near the shoreline ( i.e. if the wave's crest starts to curl over). This phenomenological modification results in the addition of two local functions applied to the wave's shape: a stretch function imitates Biesel law by progressively stretching the wave along its crest, and a plunging function simulates gravity. 6. Source: Recommended water renderer for procedural hydrological terrain (#JVRSKS) Matching note #JVRSKS: For a game with precomputed geological erosion and hydrology, the best fit is a stylized data-driven hybrid rather than runtime CFD. Reuse channel topology, banks, flow direction, discharge/drainage area, slope, depth/width, curvature, drops, junctions, obstacles, and distance-to-shore as shader/control fields. This closely matches the input assumed by scalable river animation (#QXYWAJ) and Procedural Riverscapes, which derives per-cell slope, volume, and velocity (#X3RVN8) and selects calm, turbulent, wave, cascade, vortex, and ripple primitives from terrain and flow conditions (#GU2NEL, #5NJY7V). Recommended architecture: one shared water material; rivers use generated flow maps to advect two offset normal/detail layers as in Portal 2 (#6ELMAT, #XVFV3N); lakes use low-speed wind ripples and shoreline masks; ocean uses a few art-directed Gerstner/spectral bands plus shore foam. Generate masks for turbulence/foam from normalized stream power, slope, curvature, constriction, drops, and obstacles; use depth for color/opacity and shallow-ground blending; use local feature primitives only at visually important events such as waterfalls, rapids, confluences, and rocks. Apply screen- or distance-dependent LOD, retaining flow direction and wind at distance while removing displacement and local effects (#H2E2UR, #EYM9N6). 7. Source: Water surface wavelets (#PBM2TC), Chris Wojtan, Matthias Müller-Fischer, Miles Macklin, Nuttapong Chentanez, Stefan Jeschke, Tomáš Skřivan, p. 1 Context: #RNVWWR Water Surface Wavelets #ZTWDW3 1 INTRODUCTION Matching excerpt #KZQGW5: This paper concerns the efficient and physically plausible animation and art-direction of water surface waves at large scales. Current solutions to this problem invoke numerical solutions to partial differential equations (like the shallow water equations or dispersive wave equations), or analytical solutions based on Fourier transforms. Numerical solutions excel at handling water interactions with moving obstacles, but they become expensive to compute when scaling to very large simulation domains with small (high frequency) wave details. Conversely, Fourier summation techniques excel at simulating very large domains with high-frequency details, but they cannot easily incorporate complex environmental interactions like moving boundaries and spatially-varying wind. 8. Source: Water surface wavelets (#PBM2TC), Chris Wojtan, Matthias Müller-Fischer, Miles Macklin, Nuttapong Chentanez, Stefan Jeschke, Tomáš Skřivan, p. 1 Context: #RNVWWR Water Surface Wavelets #MGX8HM 2 RELATED WORK Matching excerpt #AP28CA: Since the early days of computer animation [Schachter 1980], the main strategy for recovering the shape and motion of surface water geometry has been to approximately solve the Navier-Stokes equations. There are numerous ways to approximate these equations, and this discussion divides the techniques into analytical “spectrum-based” approaches, direct numerical simulation of partial differential equations, and hybrid approaches. We close this section by discussing methods for art-directing wave simulations. 9. Source: Water surface wavelets (#PBM2TC), Chris Wojtan, Matthias Müller-Fischer, Miles Macklin, Nuttapong Chentanez, Stefan Jeschke, Tomáš Skřivan, p. 10 Context: #RNVWWR Water Surface Wavelets #W3R46F 9 DISCUSSION Matching excerpt #MBM5XH: Overall, we believe that our approach of simulating spatially-dependent amplitudes presents an interesting twist on water wave simulation. This new direction introduces unique challenges, like increased dimensionality and an interesting link between phase and resolution. At the same time, it makes significant progress on outstanding problems in the field of physics-based animation: it introduces novel methods for artistic control, it permits extremely large simulation domains, and it enables interactive animations with fine spatial resolutions. 10. Source: Scalable real‐time animation of rivers (#XDESU9), Eric Bruneton, Fabrice Neyret, Nicolas Holzschuch, Qizhi Yu, p. 8 Context: #B9LYTR Scalable real-time animation of rivers #LQXUW2 6. Implementation and results Matching excerpt #34BVNC: channels without interrupting the animation, which is due to our procedural velocity generation. In addition, the river appearance can be easily modified using the reference wave textures. Approximate matches 1. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 6 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #CC4RWZ 8 Results Score: 0.026 Related excerpt #Q3HMFJ: A simulation of a breaking wave at a submerged shelf is shown in Figure 7. Test cases with a submerged shelf are common in coastal engineering, and represent the typical topology of a shore area. A simulation of a breaking wave at a submerged shelf in 3D was demonstrated in, e.g., [3]. With our algorithm we can recreate this phenomenon in real-time. Here, an initially smooth wave, that would not break on even ground, is approaching the submerged shelf. The decreasing fluid height causes the wave to steepen within the shallow water framework. Eventually, the wave is steep enough to fulfill Equation (4), and triggers the creation of a breaking wave. Note that the shelf is not fully aligned with the simulation grid, which causes the wave to start breaking further towards the viewer. 2. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 0 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #J39ZBT 1 Introduction Score: 0.024 Related excerpt #Q726HQ: ing of waves at the shore line can, however, not be captured with such a reduced model. We propose a new technique to enhance efficient height field liquid simulation with particle based sheets, in order to create the effect of breaking waves. As a breaking wave is a highly turbulent process that is still not fully understood, we do not aim to fully simulate this phenomenon in real-time, but to capture its most important visual features. 3. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 1 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #JPY4VD 2. Ocean dynamics simulation in deep water #B9SCHY 2.1. Spatial domain approaches #3VTQEF 2.1.1. Early works Score: 0.029 Related excerpt #ALV78Q: where N_w is the total number of waves, A_i is the amplitude of the i -th wave, \vec{k}_i = (k_{ix}, k_{iz}) its wave vector, \omega_i its pulsation and y_0 is the height of the free surface. The x-axis is oriented horizontally and points towards the coastline, the y-axis is vertical, and the z-axis is horizontal and aligned with the coastline. For each wave, the shape of the curve defined by the motion of a single point depends directly on the product between the amplitude A_i and the wave number k_i = \|\vec{k}_i\| . If k_i A_i < 0.5 , this path is similar to a trochoid. If k_i A_i = 0.5 , the shape is a cycloid. In all other cases ( k_i A_i > 0.5 ), this path cannot represent a realistic motion (see Figure 2). 4. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 6 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #XKG89F 3. Ocean dynamics simulation in shallow water #7C4MCW 3.1. Eulerian approaches Score: 0.029 Related excerpt #9TLBXN: where, as in [TDG00], A is the amplitude of a wave, \vec{k} = (k_x, k_z) its characteristic vector and w its pulsation. The user can obtain any type of shore-break by choosing from a library of precomputed profiles. The full 3D simulation is then computed by extruding the desired profile along the parallel direction to the shore (see Figure 6). 5. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 2 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #JPY4VD 2. Ocean dynamics simulation in deep water #B9SCHY 2.1. Spatial domain approaches #3VTQEF 2.1.1. Early works Score: 0.025 Related excerpt #M2AKVW: with x (respectively y ) the horizontal (resp. vertical) coordinate of a water particle at time t , x_0 and y_0 its coordinates at rest, A the wave amplitude, k the wave number and \omega the wave pulsation. Fournier and Reeves enhance this model by taking into account the transformation of the path of water particles following the topological changes of the sea bed, and by transforming their circular path into a more realistic elliptic motion. This method permits to control the waves' shape, more or less crested, through the use of different parameters, and therefore yields a more realistic result (see Figure 1). 6. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 2 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #JPY4VD 2. Ocean dynamics simulation in deep water #B9SCHY 2.1. Spatial domain approaches #3VTQEF 2.1.1. Early works Score: 0.025 Related excerpt #5ZZ3T3: The same idea was developed with a simple bump mapping approach, where normal vectors on a planar mesh are transformed using a sum of 20 cycloids [Sch80]. However, assuming that the bottom of the sea is at infinite depth limits the use of these methods since they don't include more complex phenomena such as breaking waves or waves refraction near the shore. Peachey [Pea86] introduces a depth parameter to compute the wave vector k_i of each wave, using Airy wave theory: 7. Source: Water surface wavelets (#PBM2TC), Chris Wojtan, Matthias Müller-Fischer, Miles Macklin, Nuttapong Chentanez, Stefan Jeschke, Tomáš Skřivan, p. 7 Context: #RNVWWR Water Surface Wavelets #MEQNZV 6 EXTENSIONS #5W242X 6.2 Pre-computing wave motions Score: 0.022 Related excerpt #XKHC4U: Figure 4 shows an example scene that was pre-computed using this technique. To make this result, we modeled wind effects by adding a source term S(\mathbf{x}, k, t) to Equation 18. Local wind effects like this are difficult for wavefront tracking methods which require the explicit creation of coherent wavefronts as initial conditions, but they are easy for our Eulerian method. However, unlike [Jeschke and Wojtan 2015] our simulator does not yet handle shallow water effects due to a spatially varying dispersion relation \omega , and our jittered sampling strategy makes it difficult to precisely control the wavefront phases. 8. Source: Water surface wavelets (#PBM2TC), Chris Wojtan, Matthias Müller-Fischer, Miles Macklin, Nuttapong Chentanez, Stefan Jeschke, Tomáš Skřivan, p. 1 Context: #RNVWWR Water Surface Wavelets #ZTWDW3 1 INTRODUCTION Score: 0.022 Related excerpt #784244: We derive new equations for propagating these local frequency dependent amplitudes through space; these equations result in simple 2D advection and diffusion operations that can be parallelized easily on graphics hardware, giving us interactive frame rates. We also present basic extensions to our simulator, like pre-computed wave paths and two-way solid fluid coupling. Finally, we found that this new representation provides a convenient artistic interface for hand-tuning the motion of complicated ocean simulations, and we show a prototype wave-painting interface for initializing simulations or overriding the physics with scripted motions. 9. Source: Water surface wavelets (#PBM2TC), Chris Wojtan, Matthias Müller-Fischer, Miles Macklin, Nuttapong Chentanez, Stefan Jeschke, Tomáš Skřivan, p. 1 Context: #RNVWWR Water Surface Wavelets #ZTWDW3 1 INTRODUCTION Score: 0.021 Related excerpt #KZQGW5: This paper concerns the efficient and physically plausible animation and art-direction of water surface waves at large scales. Current solutions to this problem invoke numerical solutions to partial differential equations (like the shallow water equations or dispersive wave equations), or analytical solutions based on Fourier transforms. Numerical solutions excel at handling water interactions with moving obstacles, but they become expensive to compute when scaling to very large simulation domains with small (high frequency) wave details. Conversely, Fourier summation techniques excel at simulating very large domains with high-frequency details, but they cannot easily incorporate complex environmental interactions like moving boundaries and spatially-varying wind. 10. Source: Scalable real‐time animation of rivers (#XDESU9), Eric Bruneton, Fabrice Neyret, Nicolas Holzschuch, Qizhi Yu, p. 6 Context: #B9LYTR Scalable real-time animation of rivers #NRD5JU 5. Adaptive texture advection #KWALBE 5.2. Sprite-based texturing Score: 0.021 Related excerpt #DLLLS4: such as simple flow fluctuations or wind ripples. We ignore individual waves such as stationary shockwaves or hydraulic jumps, which are not advected. In general, waves are not the same everywhere in the fluid. For instance wind ripples do not appear in wind shadowed regions. In order to reproduce this, our particles carry several kinds of waves simultaneously. During rendering we mix these waves with shaping and masking rules analog to the ones used in [BHN07]. We either use a user-defined map or a procedural rule (based on position, slope, etc) to locally modulate the amplitude of each kind of wave, or we use global parameters to control the wave appearance at the scene level (wavelength, wind direction, etc.). ### 35. Assistant tool calls #### Tool call: `get_document` ```json { "id": "8SERGP" } ``` #### Tool call: `get_document` ```json { "id": "RBS5K6" } ``` #### Tool call: `get_document` ```json { "id": "CWC7H9" } ``` #### Tool call: `get_document` ```json { "id": "869NHK" } ``` #### Tool call: `get_document` ```json { "id": "C4AY2M" } ``` ### 36. Tool result: get_document DOCUMENT #8SERGP Title: Real-time Breaking Waves for Shallow Water Simulations Outline: - 1 #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations - 1.1 #XUY95Y Abstract - 1.2 #J39ZBT 1 Introduction - 1.3 #LSRGTK 2 Related Work - 1.4 #AWDWVP 3 Shallow Water Simulations - 1.5 #PHN7AY 4 Wave Simulation - 1.6 #JL4FVP 5 Wave Patch Generation: - 1.7 #8ES8PA 6 Rendering the Waves - 1.8 #B8YMKE 7 Two-Way Rigid Body Coupling - 1.9 #CC4RWZ 8 Results - 1.10 #QQ7TWA 9 Conclusions - 1.11 #SPNKU9 10 Acknowledgements - 1.12 #CKPSGF References ### 37. Tool result: get_document DOCUMENT #RBS5K6 Title: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water Outline: - 1 #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water - 1.1 #KGMBXL Abstract - 1.2 #9QMYPL 1. Introduction - 1.3 #JZMDNB 2. Previous Work - 1.4 #VR4JRQ 3. Overview - 1.5 #34V9L7 4. Adaptive Curvature Flow - 1.6 #Z68DF9 5. Real-Time Foam - 1.6.1 #T4PBCD 5.1. Foam Formation - 1.6.2 #P6BSN6 5.2. Layer Creation - 1.6.3 #FL4KNF 5.3. Layer Compositing - 1.7 #T8YYAV 6. Results - 1.8 #JEPXQL 7. Conclusions and Future Work - 1.9 #YZ6NYP References ### 38. Tool result: get_document DOCUMENT #CWC7H9 Title: Real-time Rendering of Enhanced Shallow Water Fluid Simulations Outline: - 1 #3XLN3C Real-time Rendering of Enhanced Shallow Water Fluid Simulations - 1.1 #SDDXFP Abstract - 1.2 #D9SXF3 1. Introduction - 1.2.1 #RNG4NC 1.1. Related Work - 1.2.1.1 #ESVL3G 119 2. Fluid simulation - 1.2.1.2 #HDCYLG 149 3. Additional surface detail - 1.2.1.3 #CQWBFA 157 3.1. Lower scale detail - 1.2.1.4 #XEPFKX 179 3.2. Surface Foam - 1.3 #5GWRQA 4. Photon-based Caustics - 1.3.1 #F8ATT5 272 5. Screen-space Refraction and reflection - 1.4 #GKHL8Q 6. Results and Discussion - 1.5 #XHMJUD 7. Conclusions - 1.6 #WA3PCR Acknowledgements ### 39. Tool result: get_document DOCUMENT #869NHK Title: Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning Outline: - 1 #WADEM9 Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning - 2 #5R6DEX Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning - 2.1 #2BJMND ABSTRACT - 2.2 #L9YLTY Introduction - 2.3 #UQWEYD Overview of Our Approach - 2.3.1 #Z6PB8R The Saturation Function - 2.3.2 #4HFS63 The Halftone Mask - 2.3.3 #J3EGSN Applying the Mask - 2.4 #LP9TTY Results - 2.5 #7FYCN5 Conclusion and Further Work - 2.6 #SRXZMM References - 2.7 #DJAVLH BIBLIOGRAPHY ### 40. Tool result: get_document DOCUMENT #C4AY2M Title: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics Outline: - 1 #QZPELE A survey of ocean simulation and rendering techniques in computer graphics - 1.1 #47WJV5 Abstract - 1.2 #67ZZEA 1. Introduction - 1.3 #JPY4VD 2. Ocean dynamics simulation in deep water - 1.3.1 #B9SCHY 2.1. Spatial domain approaches - 1.3.1.1 #3VTQEF 2.1.1. Early works - 1.3.1.2 #W9ZUCV 2.1.2. GPU implementations - 1.3.1.3 #32XXKC 2.1.3. Adaptive schemes - 1.3.2 #96ENPE 2.2. Fourier domain approaches - 1.3.2.1 #Z39SP2 2.2.1. General methods - 1.3.2.2 #2XBNYQ 2.2.2. Level-Of-Detail and GPU implementations - 1.3.3 #5KSC3E 2.3. Hybrid approaches - 1.3.4 #VEG3CE 2.4. Discussion - 1.4 #XKG89F 3. Ocean dynamics simulation in shallow water - 1.4.1 #7C4MCW 3.1. Eulerian approaches - 1.4.2 #WB9J3L 3.2. Lagrangian approaches - 1.4.3 #ZEVP5C 3.3. Hybrid approaches - 1.4.4 #7ZY9G2 3.4. Discussion - 1.5 #8TWR84 4. Realistic ocean surface rendering and lighting - 1.5.1 #UKRC7P 4.1. Foam and spray - 1.5.1.1 #KCB376 4.1.1. Empirical models - 1.5.1.2 #7DVESV 4.1.2. Particle systems - 1.5.2 #TDPWBG 4.2. Light-water interactions - 1.5.2.1 #9KEXGS 4.2.1. First order approximation - 1.5.2.2 #5V9HHE 4.2.2. Multiple order approximation - 1.5.3 #D7BME4 4.3. Discussion - 1.6 #4KX5BA 5. Conclusion - 1.7 #23RGF3 Acknowledgements - 1.8 #RX2UU9 References ### 41. Assistant Yeah—this corpus actually has a pretty direct **“fake the expensive 3D bits only where they matter”** route. ### Best match: breaking waves as local particle sheets **Real-time Breaking Waves for Shallow Water Simulations** is almost exactly your idea (#8SERGP). It keeps the main sea as an inexpensive **2D height-field/shallow-water simulation**, detects steep wave fronts near shallow terrain, and only then spawns a connected sheet of particles to form the overturning crest. When that sheet hits the surface, it turns into droplets and foam (#KHRCTA). So the expensive-looking 3D effect exists only temporarily around a breaking wave—not throughout the ocean volume. It also adds ordinary particles along the crest for spray and uses bump mapping for small wave detail (#N8F4SP). The submerged-shelf example explicitly demonstrates bathymetry causing a wave to steepen and break near shore (#Q3HMFJ). The limitation is that it targets coherent, larger breakers rather than chaotic water containing thousands of tiny splashes (#TAFHNN). ### For volumetric-looking water and foam **A Layered Particle-Based Fluid Model** is the closest source for actual volumetric appearance (#RBS5K6). Its useful trick is primarily in the **rendering**: - splat particles into front/back depth surfaces; - accumulate a separate thickness buffer; - smooth the reconstructed surface in screen space; - composite separate water and foam layers. That approximates light attenuation through a volume without voxelizing or ray-marching a full fluid (#G3TYUA; #72YLNM). It can even place foam behind the front water surface, giving submerged bubbles and plunge-pool foam actual depth (#LSFXLY). The paper’s simulation is particle-based, so adopting the whole system could still be relatively heavy. But its **depth/thickness-layer renderer could be applied only to locally spawned breaker and splash particles**. ### Cheap foam, splash, and optical detail **Real-time Rendering of Enhanced Shallow Water Fluid Simulations** layers visual effects over a modest shallow-water model (#CWC7H9): - advected surface foam; - external/nonphysical high-frequency detail; - billboard splash particles; - screen-space reflection and refraction; - caustics. The foam and small-scale detail are specifically presented as cheap additions that noticeably improve the result (#BVUXWL); together they reportedly stayed below 2 ms in the tested setup (#P6Z6YL). Splash particles are rendered as depth-aware spherical billboards rather than reconstructed fluid geometry (#D98XHG). For an even cheaper foam layer, **Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning** uses a changing halftone mask so individual foam patches appear to pop and dissipate rather than just fading translucently (#869NHK; #EP8V8T). This is mainly a rendering hack, but potentially a very effective shoreline layer. ### Large-scale offshore waves **Water Surface Wavelets** is the strongest source for a large ocean that remains interactive (#PBM2TC). Instead of resolving every wave height at full resolution, it transports slowly varying, frequency-dependent amplitudes using GPU-friendly 2D advection and diffusion, then reconstructs the detailed surface (#784244). It also supports explicit artistic overriding or “painting” of wave behavior. The catch: it does not itself solve the shoreline-breaker problem. Its formulation is for efficient, physically plausible large-scale surface waves; shallow-water effects require a separate treatment (#XKHC4U). So it makes sense as the **offshore layer**, not the whole solution. ### A sensible hybrid from these papers I’d structure it like this: 1. **Open ocean:** Gerstner/spectral waves or surface wavelets for large-scale displacement. 2. **Near-shore band:** a low-resolution shallow-water height field driven by seabed depth. 3. **Breaker detection:** use depth, wave steepness, and forward velocity to identify crests. 4. **Local 3D event:** spawn a ribbon/connected particle sheet only along detected breaker fronts, following Thürey et al. (#2S99TP). 5. **Secondary particles:** emit sparse spray droplets from the crest and impact points. 6. **Foam field:** write impacts and breaking intensity into an advected 2D foam texture; use halftone/noise-based dissipation. 7. **Volumetric accents:** for close breakers, render the sheet, spray, and foam through front/back depth plus thickness buffers rather than a true volumetric solver. 8. **Shader detail:** add normal-map ripples, Fresnel reflection/refraction, shallow-water color, and optional caustics. That gives you a mostly **2D/surface-based ocean with sparse event-driven 3D geometry**. The three priority reads are **Breaking Waves** (#8SERGP), **Layered Particle-Based Fluid** (#RBS5K6), and **Enhanced Shallow Water Rendering** (#CWC7H9); the ocean survey is useful afterward for mapping the alternatives (#C4AY2M). ### 42. Tool result: search_text Exact matches 1. Source: Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning (#869NHK), Ian Parberry, Jennifer R. Alford, Mary Yingst, p. 1 Context: #5R6DEX Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning #L9YLTY Introduction Matching excerpt #XM3XNV: Real-time animation and rendering of ocean waves is often seen in video games, and adding foam to the waves lends an added level of realism. We describe a fast and effective method for rendering ocean wave foam by augmenting traditional texture based foam saturation methods with techniques from halftoning. 2. Source: Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning (#869NHK), Ian Parberry, Jennifer R. Alford, Mary Yingst, p. 5 Context: #5R6DEX Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning #LP9TTY Results Matching excerpt #RMEZSJ: Still pictures such as shown in Figure 7 and Figure 8 do not adequately capture the full effect of our algorithm. Figure 9 shows how foam bubbles fade and pop over time in the wake of each wave. This can be seen to best advantage in an animation such as the one we have placed online at [10]. 3. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 6 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #CC4RWZ 8 Results Matching excerpt #Q3HMFJ: A simulation of a breaking wave at a submerged shelf is shown in Figure 7. Test cases with a submerged shelf are common in coastal engineering, and represent the typical topology of a shore area. A simulation of a breaking wave at a submerged shelf in 3D was demonstrated in, e.g., [3]. With our algorithm we can recreate this phenomenon in real-time. Here, an initially smooth wave, that would not break on even ground, is approaching the submerged shelf. The decreasing fluid height causes the wave to steepen within the shallow water framework. Eventually, the wave is steep enough to fulfill Equation (4), and triggers the creation of a breaking wave. Note that the shelf is not fully aligned with the simulation grid, which causes the wave to start breaking further towards the viewer. 4. Source: Procedural Riverscapes (#AK7NGE), A. Peytavie, B. Benes, E. Galin, E. Guérin, J. Gain, T. Dupont, Y. Cortial, p. 6 Context: #JJE8HN Procedural Riverscapes #9ZYJP2 6. Animated Procedural River Model #U6BTCY 6.1. Riverflow Primitives Matching excerpt #GU2NEL: We have implemented a range of procedural primitives with characteristic dynamics (Figure 16), namely: calm, turbulent, wave, cascade, vortex, and ripple primitives (see the accompanying video for their animation). Calm water primitives are generated in regions with low turbulence and produce only swells and damped ripples. In contrast, turbulent water primitives are created where the water is agitated and the velocity high. Wave primitives approximate local crests and troughs, often dictated by the riverbed topography. Cascade primitives represent a more extreme version of this effect and include a corresponding plunge pool. Vortex primitives produce swirling that typically occurs downstream of under-water obstacles, such as rocks. Finally, ripples capture high frequency disturbance of the water surface from crosswinds and other sources. We also designed particular primitives for specific effects, such as echoing water ripples that approximate the complex movement of water interacting with river banks. By design it is easy to code new waterflow primitives for inclusion in the blend-flow tree. 5. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 2 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #JPY4VD 2. Ocean dynamics simulation in deep water #B9SCHY 2.1. Spatial domain approaches #3VTQEF 2.1.1. Early works Matching excerpt #FQB3R8: Gonzato and Le Saec [GS99] modify this model when the starting point of a plunging breaking wave is detected near the shoreline ( i.e. if the wave's crest starts to curl over). This phenomenological modification results in the addition of two local functions applied to the wave's shape: a stretch function imitates Biesel law by progressively stretching the wave along its crest, and a plunging function simulates gravity. 6. Source: Recommended water renderer for procedural hydrological terrain (#JVRSKS) Matching note #JVRSKS: For a game with precomputed geological erosion and hydrology, the best fit is a stylized data-driven hybrid rather than runtime CFD. Reuse channel topology, banks, flow direction, discharge/drainage area, slope, depth/width, curvature, drops, junctions, obstacles, and distance-to-shore as shader/control fields. This closely matches the input assumed by scalable river animation (#QXYWAJ) and Procedural Riverscapes, which derives per-cell slope, volume, and velocity (#X3RVN8) and selects calm, turbulent, wave, cascade, vortex, and ripple primitives from terrain and flow conditions (#GU2NEL, #5NJY7V). Recommended architecture: one shared water material; rivers use generated flow maps to advect two offset normal/detail layers as in Portal 2 (#6ELMAT, #XVFV3N); lakes use low-speed wind ripples and shoreline masks; ocean uses a few art-directed Gerstner/spectral bands plus shore foam. Generate masks for turbulence/foam from normalized stream power, slope, curvature, constriction, drops, and obstacles; use depth for color/opacity and shallow-ground blending; use local feature primitives only at visually important events such as waterfalls, rapids, confluences, and rocks. Apply screen- or distance-dependent LOD, retaining flow direction and wind at distance while removing displacement and local effects (#H2E2UR, #EYM9N6). 7. Source: Water surface wavelets (#PBM2TC), Chris Wojtan, Matthias Müller-Fischer, Miles Macklin, Nuttapong Chentanez, Stefan Jeschke, Tomáš Skřivan, p. 1 Context: #RNVWWR Water Surface Wavelets #ZTWDW3 1 INTRODUCTION Matching excerpt #KZQGW5: This paper concerns the efficient and physically plausible animation and art-direction of water surface waves at large scales. Current solutions to this problem invoke numerical solutions to partial differential equations (like the shallow water equations or dispersive wave equations), or analytical solutions based on Fourier transforms. Numerical solutions excel at handling water interactions with moving obstacles, but they become expensive to compute when scaling to very large simulation domains with small (high frequency) wave details. Conversely, Fourier summation techniques excel at simulating very large domains with high-frequency details, but they cannot easily incorporate complex environmental interactions like moving boundaries and spatially-varying wind. 8. Source: Water surface wavelets (#PBM2TC), Chris Wojtan, Matthias Müller-Fischer, Miles Macklin, Nuttapong Chentanez, Stefan Jeschke, Tomáš Skřivan, p. 1 Context: #RNVWWR Water Surface Wavelets #MGX8HM 2 RELATED WORK Matching excerpt #AP28CA: Since the early days of computer animation [Schachter 1980], the main strategy for recovering the shape and motion of surface water geometry has been to approximately solve the Navier-Stokes equations. There are numerous ways to approximate these equations, and this discussion divides the techniques into analytical “spectrum-based” approaches, direct numerical simulation of partial differential equations, and hybrid approaches. We close this section by discussing methods for art-directing wave simulations. 9. Source: Water surface wavelets (#PBM2TC), Chris Wojtan, Matthias Müller-Fischer, Miles Macklin, Nuttapong Chentanez, Stefan Jeschke, Tomáš Skřivan, p. 10 Context: #RNVWWR Water Surface Wavelets #W3R46F 9 DISCUSSION Matching excerpt #MBM5XH: Overall, we believe that our approach of simulating spatially-dependent amplitudes presents an interesting twist on water wave simulation. This new direction introduces unique challenges, like increased dimensionality and an interesting link between phase and resolution. At the same time, it makes significant progress on outstanding problems in the field of physics-based animation: it introduces novel methods for artistic control, it permits extremely large simulation domains, and it enables interactive animations with fine spatial resolutions. 10. Source: Scalable real‐time animation of rivers (#XDESU9), Eric Bruneton, Fabrice Neyret, Nicolas Holzschuch, Qizhi Yu, p. 8 Context: #B9LYTR Scalable real-time animation of rivers #LQXUW2 6. Implementation and results Matching excerpt #34BVNC: channels without interrupting the animation, which is due to our procedural velocity generation. In addition, the river appearance can be easily modified using the reference wave textures. Approximate matches 1. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 6 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #CC4RWZ 8 Results Score: 0.026 Related excerpt #Q3HMFJ: A simulation of a breaking wave at a submerged shelf is shown in Figure 7. Test cases with a submerged shelf are common in coastal engineering, and represent the typical topology of a shore area. A simulation of a breaking wave at a submerged shelf in 3D was demonstrated in, e.g., [3]. With our algorithm we can recreate this phenomenon in real-time. Here, an initially smooth wave, that would not break on even ground, is approaching the submerged shelf. The decreasing fluid height causes the wave to steepen within the shallow water framework. Eventually, the wave is steep enough to fulfill Equation (4), and triggers the creation of a breaking wave. Note that the shelf is not fully aligned with the simulation grid, which causes the wave to start breaking further towards the viewer. 2. Source: Real-time Breaking Waves for Shallow Water Simulations (#8SERGP), Markus Gross, Matthias Müller-Fischer, Nils Thürey, Simon Schirm, p. 0 Context: #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations #J39ZBT 1 Introduction Score: 0.024 Related excerpt #Q726HQ: ing of waves at the shore line can, however, not be captured with such a reduced model. We propose a new technique to enhance efficient height field liquid simulation with particle based sheets, in order to create the effect of breaking waves. As a breaking wave is a highly turbulent process that is still not fully understood, we do not aim to fully simulate this phenomenon in real-time, but to capture its most important visual features. 3. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 1 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #JPY4VD 2. Ocean dynamics simulation in deep water #B9SCHY 2.1. Spatial domain approaches #3VTQEF 2.1.1. Early works Score: 0.029 Related excerpt #ALV78Q: where N_w is the total number of waves, A_i is the amplitude of the i -th wave, \vec{k}_i = (k_{ix}, k_{iz}) its wave vector, \omega_i its pulsation and y_0 is the height of the free surface. The x-axis is oriented horizontally and points towards the coastline, the y-axis is vertical, and the z-axis is horizontal and aligned with the coastline. For each wave, the shape of the curve defined by the motion of a single point depends directly on the product between the amplitude A_i and the wave number k_i = \|\vec{k}_i\| . If k_i A_i < 0.5 , this path is similar to a trochoid. If k_i A_i = 0.5 , the shape is a cycloid. In all other cases ( k_i A_i > 0.5 ), this path cannot represent a realistic motion (see Figure 2). 4. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 6 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #XKG89F 3. Ocean dynamics simulation in shallow water #7C4MCW 3.1. Eulerian approaches Score: 0.029 Related excerpt #9TLBXN: where, as in [TDG00], A is the amplitude of a wave, \vec{k} = (k_x, k_z) its characteristic vector and w its pulsation. The user can obtain any type of shore-break by choosing from a library of precomputed profiles. The full 3D simulation is then computed by extruding the desired profile along the parallel direction to the shore (see Figure 6). 5. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 2 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #JPY4VD 2. Ocean dynamics simulation in deep water #B9SCHY 2.1. Spatial domain approaches #3VTQEF 2.1.1. Early works Score: 0.025 Related excerpt #M2AKVW: with x (respectively y ) the horizontal (resp. vertical) coordinate of a water particle at time t , x_0 and y_0 its coordinates at rest, A the wave amplitude, k the wave number and \omega the wave pulsation. Fournier and Reeves enhance this model by taking into account the transformation of the path of water particles following the topological changes of the sea bed, and by transforming their circular path into a more realistic elliptic motion. This method permits to control the waves' shape, more or less crested, through the use of different parameters, and therefore yields a more realistic result (see Figure 1). 6. Source: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics (#C4AY2M), B. Crespin, D. Ghazanfarpour, E. Darles, J.-C. Gonzato, p. 2 Context: #QZPELE A survey of ocean simulation and rendering techniques in computer graphics #JPY4VD 2. Ocean dynamics simulation in deep water #B9SCHY 2.1. Spatial domain approaches #3VTQEF 2.1.1. Early works Score: 0.025 Related excerpt #5ZZ3T3: The same idea was developed with a simple bump mapping approach, where normal vectors on a planar mesh are transformed using a sum of 20 cycloids [Sch80]. However, assuming that the bottom of the sea is at infinite depth limits the use of these methods since they don't include more complex phenomena such as breaking waves or waves refraction near the shore. Peachey [Pea86] introduces a depth parameter to compute the wave vector k_i of each wave, using Airy wave theory: 7. Source: Water surface wavelets (#PBM2TC), Chris Wojtan, Matthias Müller-Fischer, Miles Macklin, Nuttapong Chentanez, Stefan Jeschke, Tomáš Skřivan, p. 7 Context: #RNVWWR Water Surface Wavelets #MEQNZV 6 EXTENSIONS #5W242X 6.2 Pre-computing wave motions Score: 0.022 Related excerpt #XKHC4U: Figure 4 shows an example scene that was pre-computed using this technique. To make this result, we modeled wind effects by adding a source term S(\mathbf{x}, k, t) to Equation 18. Local wind effects like this are difficult for wavefront tracking methods which require the explicit creation of coherent wavefronts as initial conditions, but they are easy for our Eulerian method. However, unlike [Jeschke and Wojtan 2015] our simulator does not yet handle shallow water effects due to a spatially varying dispersion relation \omega , and our jittered sampling strategy makes it difficult to precisely control the wavefront phases. 8. Source: Water surface wavelets (#PBM2TC), Chris Wojtan, Matthias Müller-Fischer, Miles Macklin, Nuttapong Chentanez, Stefan Jeschke, Tomáš Skřivan, p. 1 Context: #RNVWWR Water Surface Wavelets #ZTWDW3 1 INTRODUCTION Score: 0.022 Related excerpt #784244: We derive new equations for propagating these local frequency dependent amplitudes through space; these equations result in simple 2D advection and diffusion operations that can be parallelized easily on graphics hardware, giving us interactive frame rates. We also present basic extensions to our simulator, like pre-computed wave paths and two-way solid fluid coupling. Finally, we found that this new representation provides a convenient artistic interface for hand-tuning the motion of complicated ocean simulations, and we show a prototype wave-painting interface for initializing simulations or overriding the physics with scripted motions. 9. Source: Water surface wavelets (#PBM2TC), Chris Wojtan, Matthias Müller-Fischer, Miles Macklin, Nuttapong Chentanez, Stefan Jeschke, Tomáš Skřivan, p. 1 Context: #RNVWWR Water Surface Wavelets #ZTWDW3 1 INTRODUCTION Score: 0.021 Related excerpt #KZQGW5: This paper concerns the efficient and physically plausible animation and art-direction of water surface waves at large scales. Current solutions to this problem invoke numerical solutions to partial differential equations (like the shallow water equations or dispersive wave equations), or analytical solutions based on Fourier transforms. Numerical solutions excel at handling water interactions with moving obstacles, but they become expensive to compute when scaling to very large simulation domains with small (high frequency) wave details. Conversely, Fourier summation techniques excel at simulating very large domains with high-frequency details, but they cannot easily incorporate complex environmental interactions like moving boundaries and spatially-varying wind. 10. Source: Scalable real‐time animation of rivers (#XDESU9), Eric Bruneton, Fabrice Neyret, Nicolas Holzschuch, Qizhi Yu, p. 6 Context: #B9LYTR Scalable real-time animation of rivers #NRD5JU 5. Adaptive texture advection #KWALBE 5.2. Sprite-based texturing Score: 0.021 Related excerpt #DLLLS4: such as simple flow fluctuations or wind ripples. We ignore individual waves such as stationary shockwaves or hydraulic jumps, which are not advected. In general, waves are not the same everywhere in the fluid. For instance wind ripples do not appear in wind shadowed regions. In order to reproduce this, our particles carry several kinds of waves simultaneously. During rendering we mix these waves with shaping and masking rules analog to the ones used in [BHN07]. We either use a user-defined map or a procedural rule (based on position, slope, etc) to locally modulate the amplitude of each kind of wave, or we use global parameters to control the wave appearance at the scene level (wavelength, wind direction, etc.). ### 43. Assistant tool calls #### Tool call: `get_document` ```json { "id": "8SERGP" } ``` #### Tool call: `get_document` ```json { "id": "RBS5K6" } ``` #### Tool call: `get_document` ```json { "id": "CWC7H9" } ``` #### Tool call: `get_document` ```json { "id": "869NHK" } ``` #### Tool call: `get_document` ```json { "id": "C4AY2M" } ``` ### 44. Tool result: get_document DOCUMENT #8SERGP Title: Real-time Breaking Waves for Shallow Water Simulations Outline: - 1 #FA7BE4 Real-time Breaking Waves for Shallow Water Simulations - 1.1 #XUY95Y Abstract - 1.2 #J39ZBT 1 Introduction - 1.3 #LSRGTK 2 Related Work - 1.4 #AWDWVP 3 Shallow Water Simulations - 1.5 #PHN7AY 4 Wave Simulation - 1.6 #JL4FVP 5 Wave Patch Generation: - 1.7 #8ES8PA 6 Rendering the Waves - 1.8 #B8YMKE 7 Two-Way Rigid Body Coupling - 1.9 #CC4RWZ 8 Results - 1.10 #QQ7TWA 9 Conclusions - 1.11 #SPNKU9 10 Acknowledgements - 1.12 #CKPSGF References ### 45. Tool result: get_document DOCUMENT #RBS5K6 Title: A Layered Particle-Based Fluid Model for Real-Time Rendering of Water Outline: - 1 #5NFAXU A Layered Particle-Based Fluid Model for Real-Time Rendering of Water - 1.1 #KGMBXL Abstract - 1.2 #9QMYPL 1. Introduction - 1.3 #JZMDNB 2. Previous Work - 1.4 #VR4JRQ 3. Overview - 1.5 #34V9L7 4. Adaptive Curvature Flow - 1.6 #Z68DF9 5. Real-Time Foam - 1.6.1 #T4PBCD 5.1. Foam Formation - 1.6.2 #P6BSN6 5.2. Layer Creation - 1.6.3 #FL4KNF 5.3. Layer Compositing - 1.7 #T8YYAV 6. Results - 1.8 #JEPXQL 7. Conclusions and Future Work - 1.9 #YZ6NYP References ### 46. Tool result: get_document DOCUMENT #CWC7H9 Title: Real-time Rendering of Enhanced Shallow Water Fluid Simulations Outline: - 1 #3XLN3C Real-time Rendering of Enhanced Shallow Water Fluid Simulations - 1.1 #SDDXFP Abstract - 1.2 #D9SXF3 1. Introduction - 1.2.1 #RNG4NC 1.1. Related Work - 1.2.1.1 #ESVL3G 119 2. Fluid simulation - 1.2.1.2 #HDCYLG 149 3. Additional surface detail - 1.2.1.3 #CQWBFA 157 3.1. Lower scale detail - 1.2.1.4 #XEPFKX 179 3.2. Surface Foam - 1.3 #5GWRQA 4. Photon-based Caustics - 1.3.1 #F8ATT5 272 5. Screen-space Refraction and reflection - 1.4 #GKHL8Q 6. Results and Discussion - 1.5 #XHMJUD 7. Conclusions - 1.6 #WA3PCR Acknowledgements ### 47. Tool result: get_document DOCUMENT #869NHK Title: Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning Outline: - 1 #WADEM9 Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning - 2 #5R6DEX Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning - 2.1 #2BJMND ABSTRACT - 2.2 #L9YLTY Introduction - 2.3 #UQWEYD Overview of Our Approach - 2.3.1 #Z6PB8R The Saturation Function - 2.3.2 #4HFS63 The Halftone Mask - 2.3.3 #J3EGSN Applying the Mask - 2.4 #LP9TTY Results - 2.5 #7FYCN5 Conclusion and Further Work - 2.6 #SRXZMM References - 2.7 #DJAVLH BIBLIOGRAPHY ### 48. Tool result: get_document DOCUMENT #C4AY2M Title: A Survey of Ocean Simulation and Rendering Techniques in Computer Graphics Outline: - 1 #QZPELE A survey of ocean simulation and rendering techniques in computer graphics - 1.1 #47WJV5 Abstract - 1.2 #67ZZEA 1. Introduction - 1.3 #JPY4VD 2. Ocean dynamics simulation in deep water - 1.3.1 #B9SCHY 2.1. Spatial domain approaches - 1.3.1.1 #3VTQEF 2.1.1. Early works - 1.3.1.2 #W9ZUCV 2.1.2. GPU implementations - 1.3.1.3 #32XXKC 2.1.3. Adaptive schemes - 1.3.2 #96ENPE 2.2. Fourier domain approaches - 1.3.2.1 #Z39SP2 2.2.1. General methods - 1.3.2.2 #2XBNYQ 2.2.2. Level-Of-Detail and GPU implementations - 1.3.3 #5KSC3E 2.3. Hybrid approaches - 1.3.4 #VEG3CE 2.4. Discussion - 1.4 #XKG89F 3. Ocean dynamics simulation in shallow water - 1.4.1 #7C4MCW 3.1. Eulerian approaches - 1.4.2 #WB9J3L 3.2. Lagrangian approaches - 1.4.3 #ZEVP5C 3.3. Hybrid approaches - 1.4.4 #7ZY9G2 3.4. Discussion - 1.5 #8TWR84 4. Realistic ocean surface rendering and lighting - 1.5.1 #UKRC7P 4.1. Foam and spray - 1.5.1.1 #KCB376 4.1.1. Empirical models - 1.5.1.2 #7DVESV 4.1.2. Particle systems - 1.5.2 #TDPWBG 4.2. Light-water interactions - 1.5.2.1 #9KEXGS 4.2.1. First order approximation - 1.5.2.2 #5V9HHE 4.2.2. Multiple order approximation - 1.5.3 #D7BME4 4.3. Discussion - 1.6 #4KX5BA 5. Conclusion - 1.7 #23RGF3 Acknowledgements - 1.8 #RX2UU9 References ### 49. Assistant Yeah—this corpus actually has a pretty direct **“fake the expensive 3D bits only where they matter”** route. ### Best match: breaking waves as local particle sheets **Real-time Breaking Waves for Shallow Water Simulations** is almost exactly your idea (#8SERGP). It keeps the main sea as an inexpensive **2D height-field/shallow-water simulation**, detects steep wave fronts near shallow terrain, and only then spawns a connected sheet of particles to form the overturning crest. When that sheet hits the surface, it turns into droplets and foam (#KHRCTA). So the expensive-looking 3D effect exists only temporarily around a breaking wave—not throughout the ocean volume. It also adds ordinary particles along the crest for spray and uses bump mapping for small wave detail (#N8F4SP). The submerged-shelf example explicitly demonstrates bathymetry causing a wave to steepen and break near shore (#Q3HMFJ). The limitation is that it targets coherent, larger breakers rather than chaotic water containing thousands of tiny splashes (#TAFHNN). ### For volumetric-looking water and foam **A Layered Particle-Based Fluid Model** is the closest source for actual volumetric appearance (#RBS5K6). Its useful trick is primarily in the **rendering**: - splat particles into front/back depth surfaces; - accumulate a separate thickness buffer; - smooth the reconstructed surface in screen space; - composite separate water and foam layers. That approximates light attenuation through a volume without voxelizing or ray-marching a full fluid (#G3TYUA; #72YLNM). It can even place foam behind the front water surface, giving submerged bubbles and plunge-pool foam actual depth (#LSFXLY). The paper’s simulation is particle-based, so adopting the whole system could still be relatively heavy. But its **depth/thickness-layer renderer could be applied only to locally spawned breaker and splash particles**. ### Cheap foam, splash, and optical detail **Real-time Rendering of Enhanced Shallow Water Fluid Simulations** layers visual effects over a modest shallow-water model (#CWC7H9): - advected surface foam; - external/nonphysical high-frequency detail; - billboard splash particles; - screen-space reflection and refraction; - caustics. The foam and small-scale detail are specifically presented as cheap additions that noticeably improve the result (#BVUXWL); together they reportedly stayed below 2 ms in the tested setup (#P6Z6YL). Splash particles are rendered as depth-aware spherical billboards rather than reconstructed fluid geometry (#D98XHG). For an even cheaper foam layer, **Very Fast Real-Time Ocean Wave Foam Rendering Using Halftoning** uses a changing halftone mask so individual foam patches appear to pop and dissipate rather than just fading translucently (#869NHK; #EP8V8T). This is mainly a rendering hack, but potentially a very effective shoreline layer. ### Large-scale offshore waves **Water Surface Wavelets** is the strongest source for a large ocean that remains interactive (#PBM2TC). Instead of resolving every wave height at full resolution, it transports slowly varying, frequency-dependent amplitudes using GPU-friendly 2D advection and diffusion, then reconstructs the detailed surface (#784244). It also supports explicit artistic overriding or “painting” of wave behavior. The catch: it does not itself solve the shoreline-breaker problem. Its formulation is for efficient, physically plausible large-scale surface waves; shallow-water effects require a separate treatment (#XKHC4U). So it makes sense as the **offshore layer**, not the whole solution. ### A sensible hybrid from these papers I’d structure it like this: 1. **Open ocean:** Gerstner/spectral waves or surface wavelets for large-scale displacement. 2. **Near-shore band:** a low-resolution shallow-water height field driven by seabed depth. 3. **Breaker detection:** use depth, wave steepness, and forward velocity to identify crests. 4. **Local 3D event:** spawn a ribbon/connected particle sheet only along detected breaker fronts, following Thürey et al. (#2S99TP). 5. **Secondary particles:** emit sparse spray droplets from the crest and impact points. 6. **Foam field:** write impacts and breaking intensity into an advected 2D foam texture; use halftone/noise-based dissipation. 7. **Volumetric accents:** for close breakers, render the sheet, spray, and foam through front/back depth plus thickness buffers rather than a true volumetric solver. 8. **Shader detail:** add normal-map ripples, Fresnel reflection/refraction, shallow-water color, and optional caustics. That gives you a mostly **2D/surface-based ocean with sparse event-driven 3D geometry**. The three priority reads are **Breaking Waves** (#8SERGP), **Layered Particle-Based Fluid** (#RBS5K6), and **Enhanced Shallow Water Rendering** (#CWC7H9); the ocean survey is useful afterward for mapping the alternatives (#C4AY2M). ### 50. User my landscape terrain is currently a bit low res feeling, i wonder if it can be smoothed out nicely in the renderer, using metal