Abstract
The performance of an interactive virtual crowd system for entertainment purposes can be greatly improved by setting a level-of-details (LOD) strategy: in distant areas, collision avoidance can even be stealthy disabled to drastically speed-up simulation and to handle huge crowds. The greatest difficulty is then to select LODs to progressively simplify simulation in an imperceptible but efficient manner. The main objective of this work is to experimentally evaluate spectators' ability to detect the presence of collisions in simulations. Factors related to the conditions of observation and simulation are studied, such as the camera angles, distance to camera, level of interpenetration or crowd density. Our main contribution is to provide a LOD selection function resulting from two perceptual studies allowing crowd system designers to scale a simulation by relaxing the collision avoidance constraint in a least perceptible manner. The relaxation of this constraint is an important source for computational resources savings. Our results reveal several misconceptions in previously used LOD selection functions and suggest yet unexplored variables to be considered. We demonstrate our function efficiency over several evaluation scenarios.
Supplemental Material
- Burstedde, C., Klauck, K., Schadschneider, A., and Zittartz, J. 2001. Simulation of pedestrian dynamics using a two-dimensional cellular automaton. Physica A: Statistical Mechanics and its Applications 295, 3--4, 507--525.Google Scholar
- Dobbyn, S., Hamill, J., O'Conor, K., and O'Sullivan, C. 2005. Geopostors: a real-time geometry/impostor crowd rendering system. Proc. Symposium on Interactive 3D Graphics and Games. Google ScholarDigital Library
- Helbing, D., and Molnar, P. 1995. Social force model for pedestrian dynamics. Physical Review E 51, 4282.Google ScholarCross Ref
- Hillaire, S., Breton, G., Ouarti, N., Cozot, R., and Lécuyer, A. 2010. Using a Visual Attention Model to Improve Gaze Tracking Systems in Interactive 3D Applications. Computer Graphics Forum 19 (6), 1830--1841.Google ScholarCross Ref
- Kapadia, M., Singh, S., Allen, B., Reinman, G., and Faloutsos, P. 2009. Steerbug: an interactive framework for specifying and detecting steering behaviors. Proc. ACM SIGGRAPH/Eurographics Symposium on Computer Animation. Google ScholarDigital Library
- Kistler, F., Wissner, M., and André, E. 2010. Level of detail based behavior control for virtual characters. In Intelligent Virtual Agents, vol. 6356 of Lecture Notes in Computer Science. Springer Berlin/Heidelberg, 118--124. Google ScholarDigital Library
- Maury, B., Roudneff Chupin, A., and Santambrogio, F. 2010. A macroscopic crowd motion model of gradient flow type. Mathematical Models and Methods in Applied Sciences 20, 10, 1787--1821.Google ScholarCross Ref
- McDonnell, R., Dobbyn, S., and O'Sullivan, C. 2005. LOD Human Representations: A Comparative Study. In Int. Workshop on Crowd Simulation (V-CROWDS'05), 101--115.Google Scholar
- McDonnell, R., Larkin, M., Dobbyn, S., Collins, S., and O'Sullivan, C. 2008. Clone attack! perception of crowd variety. ACM Transactions on Graphics 25 (3). Google ScholarDigital Library
- McDonnell, R., Larkin, M., Hernández, B., Rudomin, I., and O'Sullivan, C. 2009. Eye-catching crowds: saliency based selective variation. ACM Trans. Graph. 28, 3, 1--10. Google ScholarDigital Library
- McHugh, J., McDonnell, R., Newell, F. N., and O'Sullivan, C. 2010. Perceiving emotion in crowds: the role of dynamic body postures on the perception of emotion in crowded scenes. Experimental Brain Research 204 (3), 361--372.Google ScholarCross Ref
- Narain, R., Golas, A., Curtis, S., and Lin, M. 2009. Aggregate dynamics for dense crowd simulation. In SIGGRAPH Asia '09: ACM SIGGRAPH Asia 2009 papers. Google ScholarDigital Library
- Niederberger, C., and Gross, M. 2005. Level-of-detail for cognitive real-time characters. Visual Computer 21, 188--202. Google ScholarDigital Library
- Paris, S., Pettré, J., and Donikian, S. 2007. Pedestrian reactive navigation for crowd simulation: a predictive approach. Eurographics'07: Computer Graphics Forum 26, (3), 665--674.Google ScholarCross Ref
- Paris, S., Gerdelan, A., and O'Sullivan, C. 2009. Calod: Collision avoidance level of detail for scalable, controllable crowds. Proc. International Workshop on Motion in Games. Google ScholarDigital Library
- Pettré, J., Ciechomski, P. d. H., Mäim, J., Yersin, B., Laumond, J.-P., and Thalmann, D. 2006. Real-time navigating crowds: scalable simulation and rendering: Casa 2006 research articles. Comput. Animat. Virtual Worlds 17, 445--455. Google ScholarDigital Library
- Pettré, J., Ondřej, J., Olivier, A.-H., Crétual, A., and Donikian, S. 2009. Experiment-based modeling, simulation and validation of interactions between virtual walkers. Proc. ACM SIGGRAPH/Eurographics Symp. on Computer Animation. Google ScholarDigital Library
- Reynolds, C. W. 1987. Flocks, herds and schools: A distributed behavioral model. In SIGGRAPH '87: Proceedings of the 14th annual conference on Computer graphics and interactive techniques, ACM, New York, NY, USA, 25--34. Google ScholarDigital Library
- Samet, H. 2005. Foundations of Multidimensional and Metric Data Structures. Morgan Kaufmann Publishers Inc., San Francisco, CA, USA. Google ScholarDigital Library
- Sud, A., Andersen, E., Curtis, S., Lin, M., and Manocha, D. 2008. Real-time path planning for virtual agents in dynamic environments. ACM SIGGRAPH 2008 classes. Google ScholarDigital Library
- Tecchia, F., Loscos, C., and Chrysanthou, Y. 2002. Image-based crowd rendering. IEEE Comput. Graph. Appl. 22 (March), 36--43. Google ScholarDigital Library
- Treuille, A., Cooper, S., and Popović, Z. 2006. Continuum crowds. ACM Trans. on Graphics (SIGGRAPH 2006) 25 (3). Google ScholarDigital Library
- van den Berg, J., Patil, S., Sewall, J., Manocha, D., and Lin, M. 2008. Interactive navigation of individual agents in crowded environments. Symposium on Interactive 3D Graphics and Games (I3D 2008). Google ScholarDigital Library
- Yersin, B., Mäim, J., Pettré, J., and Thalmann, D. 2009. Crowd patches: populating large-scale virtual environments for real-time applications. Proc. Symposium on Interactive 3D Graphics and games, 207--214. Google ScholarDigital Library
Index Terms
- Imperceptible relaxation of collision avoidance constraints in virtual crowds
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