Scénarisation D'environnements Virtuels: Vers Un Équilibre Entre Contrôle, Cohérence Et Adaptabilité

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Scénarisation D'environnements Virtuels: Vers Un Équilibre Entre Contrôle, Cohérence Et Adaptabilité Scénarisation d’environnements virtuels : vers un équilibre entre contrôle, cohérence et adaptabilité Camille Barot To cite this version: Camille Barot. Scénarisation d’environnements virtuels : vers un équilibre entre contrôle, co- hérence et adaptabilité. Autre. Université de Technologie de Compiègne, 2014. Français. NNT : 2014COMP1615. tel-01130812 HAL Id: tel-01130812 https://tel.archives-ouvertes.fr/tel-01130812 Submitted on 12 Mar 2015 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Par Camille BAROT Scénarisation d’environnements virtuels : vers un équilibre entre contrôle, cohérence et adaptabilité Thèse présentée pour l’obtention du grade de Docteur de l’UTC Soutenue le 24 février 2014 Spécialité : Technologies de l’Information et des Systèmes D1615 Thèse pour l’obtention du grade de Docteur de l’Université de Technologie de Compiègne Spécialité : Technologies de l’Information et des Systèmes Scénarisation d’environnements virtuels. Vers un équilibre entre contrôle, cohérence et adaptabilité. par Camille Barot Soutenue le 24 février 2014 devant un jury composé de : M. Ronan CHAMPAGNAT Maître de Conférences (HDR) Université de la Rochelle Rapporteur M. Stéphane DONIKIAN Directeur de Recherche (HDR) INRIA Rennes-Bretagne Rapporteur M. Stacy MARSELLA Professor Northeastern University Examinateur Mme Indira MOUTTAPA-THOUVENIN Enseignant-Chercheur (HDR) Université de Technologie de Compiègne Examinatrice M. Nicolas SZILAS Maître d’Enseignement et de Recherche Université de Genève Examinateur M. Dominique LENNE Professeur Université de Technologie de Compiègne Directeur Mme Domitile LOURDEAUX Maître de Conférences (HDR) Université de Technologie de Compiègne Directrice 2 Résumé Ces travaux traitent de la scénarisation d’environnements virtuels, définie comme la spécifica- tion des déroulements possibles ou souhaitables d’une simulation, et la mise en place de mécanismes permettant de contrôler son déroulement effectif de manière dynamique. Nous visons pour cette scénarisation un ensemble d’objectifs, souvent considérés comme contradic- toires : la liberté et la capacité d’action de l’utilisateur, l’ampleur, le caractère dynamique et l’efficac- ité du contrôle exercé sur le scénario, la cohérence des comportements présentés et l’adaptabilité du système, nécessaire pour la variabilité des scénarios. Nous proposons SELDON, un modèle basé sur le contrôle centralisé et indirect d’une simulation émergente à partir de modèles du contenu scénaristique. L’environnement est peuplé de person- nages virtuels autonomes et l’utilisateur y est libre de ses actions. La scénarisation est réalisée en deux étapes : des objectifs dynamiques sont déterminés à partir de l’activité de l’utilisateur, puis un scénario est généré en fonction de ces objectifs et exécuté au travers d’ajustements sur la simulation. Le moteur DIRECTOR permet de générer et de réaliser ce scénario. DIRECTOR utilise les modèles qui sous-tendent la simulation pour prédire son évolution, et guide cette évolution au travers d’un ensemble d’ajustements indirects, qui influencent les réactions des systèmes techniques et les prises de décision des personnages. Il utilise un moteur de planification pour générer des scénarios com- posés d’étapes de prédiction, dont il suit la réalisation dans la simulation, et d’ajustements, qu’il dé- clenche. Les objectifs scénaristiques pris en compte sont à la fois dynamiques, au travers de situations prescrites et proscrites et de contraintes sur les propriétés globales du scénario, et statiques, sous la forme d’espaces de scénario. Le contenu scénaristique et les objectifs scénaristiques statiques sont représentés à l’aide de l’ensemble de langages que nous avons proposé : DOMAIN-DL, ACTIVITY-DL et CAUSALITY-DL. Ces contributions permettent d’allier la réactivité et la variabilité permises par des simulations émergentes et la pertinence des scénarios offerte par les systèmes basés sur de la planification. 3 4 Abstract Orchestration of virtual environments: Balancing control, coherence and adaptability. This work addresses the orchestration of virtual environments, defined as the specification of possible or wanted unfoldings of events in a simulation and the implementation of control mecha- nisms over the actual unfolding. We aim at a set of objectives often considered contradictory: user freedom/agency, range, dynamicity and efficiency of control over the scenario, behavioural coherence, and system adaptability, which is essential for scenario variability. We propose SELDON, a model based on centralised and indirect control of an emergent simulation. Scenario content is represented by domain and activity models in the DOMAIN-DL and ACTIVITY-DL languages. The virtual environement is populated by autonomous characters, and the user’s choices of actions are unconstrained. Orchestration is carried out in two steps: first, a set of dynamic ob- jectives is determined from the user’s profile and activity, then a scenario is generated from these objectives and executed through adjustements on the simulation. The DIRECTOR engine performs scenario generation and execution. DIRECTOR uses the simula- tion’s models to predict its evolution and guide it through a set of indirect adjustements that influence technical systems’ reactions and characters’ decisions. It uses planning to generate scenarios made up of prediction steps that DIRECTOR monitors in the simulation and adjustements that it triggers in the virtual environment. Scenario objectives can be defined dynamically through prescribed/pro- scribed situations and constraints on global scenario properties or statically as a space of scenarios of interest represented in the CAUSALITY-DL language. 5 6 Remerciements Je tiens avant tout à exprimer ma profonde gratitude à Domitile Lourdeaux, qui m’a encadrée, conseillée et soutenue tout au long de ce doctorat. Merci, Domitile, d’avoir toujours cru en moi et de m’avoir encouragée à viser plus haut. Merci aussi de m’avoir permis de trouver mes marques et de m’intégrer dans une approche existante sans jamais m’imposer un point de vue, de m’avoir laissé poursuivre mes idées même quand tu n’y croyais pas au départ. Merci enfin de m’avoir montré que l’on pouvait vraiment s’éclater en faisant de la recherche. Tu as fait de ton équipe une vraie famille, avec son arbre généalogique accroché au mur de ton bureau, et je suis heureuse d’en faire partie. Je suis fière du travail accompli à tes côtés. Je remercie également Dominique Lenne d’avoir co-encadré cette thèse. Merci de m’avoir fait confiance, et de m’avoir poussée aussi, durant la thèse certes mais également bien avant puisque c’est toi qui, dès IA01, m’a incitée à envisager la voie de la recherche. Je souhaite remercier Ronan Champagnat et Stéphane Donikian d’avoir accepté de rapporter ma thèse, et je remercie Nicolas Szilas d’avoir accepté d’en être examinateur. I thank (in English!) Stacy Marsella, for not only accepting to suffer the slings and arrows of visioconference to attend my de- fense, but also for the faith he put in me during our short time working together. Je remercie de tout cœur Indira Mouttapa Thouvenin, qui a accepté de présider mon jury de thèse, mais m’a surtout soutenue et encouragée depuis plusieurs années. Merci à tous pour vos critiques, vos remarques et vos questions qui ont fait de ma soutenance un moment d’échanges passionnants. Cette thèse n’aurait pas pu voir le jour sans le soutien de la région Picardie et du FEDER au projet ARAKIS, et je les en remercie. De même, je remercie toutes les personnes impliquées dans ce pro- jet, mais aussi dans les projets V3S et NIKITA auxquels j’ai pu participer, en particulier les groupes du CEA, du LATI et d’Emissive. Merci donc à Emmanuel Guerriero, Fabien Barati et Antoine Ferrieux avec qui j’ai été ravie de travailler avant comme pendant la thèse. Un grand merci également à Jean-Marie Burkhardt, avec qui les échanges ont été particulièrement enrichissants. Enfin, je suis très reconnais- sante à Fabrice Camus d’être venu avec moi affronter les dangers des dépôts pétroliers pour réaliser les analyses terrain, et de m’avoir encouragée sans relâche pendant toute la durée de cette thèse. Mes pensées vont à l’équipe HUMANS, et à tous ceux qui ont pu graviter autour de celle-ci à un moment où à un autre : Margot Lhommet, Pierre-Yves Gicquel, Vincent Lanquepin, Kahina Amokrane, Antoine Vincent, Dorine Dufour, Hazaël Jones, Jocelyn Thiery, Lydie Edward, Lucile Callebert, Juliette Lemaitre, Loïc Fricoteaux, Jérôme Olive, Alistair Jones, Kevin Wagrez, Thibaut Arribe... mais aussi la bande de Reviatech — Romain Lelong, Mehdi Sbaouni et Morgan Fraslin — et celle des déjeuners à l’IMI — Benjamin Diemert et Thomas Bottini. On a vécu de grands moments, et vous avez été bien plus que des collègues à mes yeux. J’espère que les traditions des journées à thèmes du mardi et des bières au Shamrock qui font rater le train perdureront, et que de nouvelles viendront s’y ajouter. Kevin Carpentier, mon acolyte de toujours, mérite son paragraphe rien qu’à lui : tu as été un binôme fantastique durant toutes ces années, et ça va beaucoup me manquer de travailler avec toi. J’espère qu’on y remédiera très vite et qu’on finira par ouvrir ensemble un grand parc d’attractions autour du storytelling, de la génération procédurale et de la synesthésie. Je remercie également le laboratoire Heudiasyc et l’équipe ICI pour leur accueil, ainsi que les étudiants de l’UTC que j’ai pu encadrer autour de différents projets pour l’équipe HUMANS et qui ont été d’une aide précieuse : Barthélémy Arribe, Yacine Badiss, Clément Boissière, Marion Cayla, Jonathan Denonain, Pierre-Henri Fricot, Thibaud Huet, Ronan Kervella, Pierre-Alexandre Kofron, 7 Julien Mazars, Aloïs Nolin, Vincent Palancher, Thierry Tang..
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