INRIA Rhône-Alpes Équipe du laboratoire GRAVIR/IMAG

1. EVASIONEnvironnements Virtuels pour l’Animation et la Synthèse d’Images d’Objets NaturelsVirtual Environments for Modeling, Animating and Rendering Natural Scenes INRIA Rhône-Alpes Équipe du laboratoire GRAVIR/IMAG Future équipe du LJK (CNRS, INPG, INRIA, UJF)

2. Who are we? The team • 6 faculties • 2 full profs : GP Bonneau (UJF), MP Cani (INPG):Scientific leader • 2 assistant profs : F Faure (UJF), F. Hetroy (INPG, sept 2004) • 2 CR1 researchers : F. Neyret (CNRS), L. Revéret (INRIA) • 4 post-doc, engineer or designer • 12 PhD students (8 with MENRT grants) History • Created in January 2003, after the scission of iMAGIS • Basis:Computer Graphics (modeling, animation, rendering)

3. Scientific focus Modeling & Visualizing Nature • Fascinating problem (vegetable, mineral, animal worlds) • Still unsolved to a large extent • Many industrial applications (from realism to real-time) • 3D feature films, Special effects, Video games • Virtual prototyping & Pedagogical Simulators (environment, geology, energy, aeronautics, surgery, cosmetics)

4. Modeling & Visualizing Nature Main challenges • Extreme complexity • Number of elements, shape, aspect, motion and deformation • Re-using models from other sciences is not always possible • Virtual clouds? Fluid dynamics & meteorology study other scales • Hair animation? FEM + collisions not applicable for 100 000 strands Use existing knowledge: Collaborate with other disciplines Combine efficiency and realism? Specific methodology + New fundamental tools

5. Scientific basisMethodology for handling complexity • Characterize the observed sub-phenomena • Represent them by coupled sub-models • Of different nature : physical model, geometry, texture, ... • Applied at different scales • Dynamically adapt the sub-models to the needs • By changing their local space and time resolution • By switching from one model to another • Validate based on human perception

6. … Methodology for handling complexityExample: meadow blowing in the wind • Wind : pattern + action • Receever : precomputed dynamics • Grass geometry : 3 levels of detail [I3D’01,Computer Animation’03]

7. Contributions1. New fundamental tools • Geometry • New shape representations • Interactive deformations • Animation • Motion control from video analysis • Physically-based simulation • Visualization of massive data-sets • Multiresolution analysis & adaptive rendering • Realistic rendering • Textures, shaders, point-based rendering

8. New fundamental toolsExample: Constant volume space deformations • Foldover-free space deformation • Rings of constant volume « swirls » Applications • Modeling virtual clay • Animating fluids [Pacific Graphics’04, SCA’05]

9. Contributions2. Application to specific natural scenes • Mineral world • Animation of lava-flows, sea, streams • Simulation of water, smoke, clouds • Vegetable world • Real-time rendering of forest • Animating meadows (grass, trees) • Animal world • Wild animals animated from video • Virtual humans: hair, skin, muscles, clothes • Real-time organs for surgery simulators

10. Application to specific natural scenesExample: Simulation of Natural Hair • New Lagrangian deformable model: Super-helices • Predicts the shape of static hair • Efficient and stable simulation of hair dynamics • Identification of hair interaction parameters • Bridging the gap between wisps & continuum Interdisciplinary work (cosmetics, mechanics) Industrial partnership (L’Oréal) [EG’05 short, SIGGRAPH’06]

11. Application to specific natural scenesExample: Simulation of Natural Hair

12. 3. Software development SOFA withCIMIT/Harvard, INRIA, ETHZ, CWU An Open Framework for Medical Simulation • Multi-institution, international effort • Aim: component sharing / exchange / comparison Kernel (release Dec 06) • Communication & interfaces Modules • FEM, Mass & springs, Particles • Rendering algorithms, • Collision detection & response

13. Scientific Collaborations International • Joint teamwith DGP, University of Toronto (2004-2006) • 6 Eurodoc grants: 6 month visit of PhD students to U. of Washington, Davis, Berkeley, Calgary, Montreal • European Network of Excellence: Aim@shape (other joint papers with UBC, ETHZ, U. of Tuebingen, UC Davis) National • Co-advised PhDs: SIAMES, MOVI, APACHE, LMC, TIMC • DEREVE 2 with LIRIS & ICA, MIDAS with TIMC, ICP • ARCs with ALCOVE, EPIDAURE, ISA, Geometrica

14. Kamelelon NatSim with Other Disciplines 2003-2005: Collaborations with the fields of • Mechanics (CEMAGREF, LEGI, L3S) • Medicine (IRCAD, TIMC) • Cognitive Sciences (U. of Geneva) • Cosmetics (l’Oreal research labs) 2005-2009: Interdisciplinary research clusters • “Environnement” &“Santé” (Rhône-Alpes Region) 2006-2009: Multidiciplinary ANR Projects • Biomechanics & Neurosciences (project Kameleon) • Botanics (project NatSim)

15. Industrial grants & transfer Public projects with technology transfer • European project Odysseous • RIAM Virtual Actors & RNTL PARI with Galilea • RIAM projects Vertigo & Prodige with Bionatics and Thales Direct grants from the industry • L’Oreal (contract 2004-2006) • CEA / CESTA (PhD grant 2004-2006) • EDF (PhD grant 2005-2007)

16. Results & Visibility • Publications (20 journal, 48 conf, 6 chapters…) • Editors: GMOD, IEEE TVCG • Conference co-chairs • EG-IEEE Visualisation’2003, IEEE Shape Modeling & Applications’05 • Paper co-chairs • EUROGRAPHICS’04, ACM-EG Symp. on Computer Animation’06 • PC members • SIGGRAPH, Eurographics, Pacific Graphics • IEEE Vis, SMI, SCA, CASA, NPAR, etc

17. Grand challenge ?Specify and control a full, animated natural scene Creation of digital content, in a difficult case • High number of similar, but different details • Allow user-input / fit specific distributions • Control motion while maintaining realism • Animate and render efficiently Reasons for tackling it? • Real-size tests & interactions between different phenomena • Interactive exploration (GPU, GRimage PC grid) • Validation through the science of human perception

18. Objectives for the next 4 years • Creation of Natural Scenes • Exploit real images, data, sketching • Combine user control with procedural details • Animating Nature: multi-disciplinary projects • Promote interactive virtual scenes as a support for experimenting and validating hypotheses • Model natural phenomena never achieved in CG • Efficient Visualization of very large scenes • Interactive exploration of hybrid data-masses • Fast, realistic rendering of natural scenes

19. EVASION Conclusion • Computer Graphics group • Competences: modeling, animation, visualization, rendering • Focus:Virtual natural scenes and phenomena • Strategic aspects within French research • Combining simulation, visualization and virtual reality • Processing huge data-sets • Applications to Environmental simulations • Applications to Biology/Health-care

20. EVASION Thank you!