Searching for good and diverse game levels

Abstract: In procedural content generation, one is often interested in generating a large number of artifacts that are not only of high quality but also diverse, in terms of gameplay, visual impression or some other criterion. We investigate several search-based approaches to creating good and diverse game content, in particular approaches based on evolution strategies with or without diversity preservation mechanisms, novelty search and random search. The content domain is game levels, more precisely map sketches for strategy games, which are meant to be used as suggestions in the Sentient Sketchbook design tool. Several diversity metrics are possible for this type of content: we investigate tile-based, objective-based and visual impression distance. We find that evolution with diversity preservation mechanisms can produce both good and diverse content, but only when using appropriate distance measures. Reversely, we can draw conclusions about the suitability of these distance measures for the domain from the comparison of diversity preserving versus blind restart evolutionary algorithms.peer-reviewe

A Partition-Based Random Search Method for Multimodal Optimization

Practical optimization problems are often too complex to be formulated exactly. Knowing multiple good alternatives can help decision-makers easily switch solutions when needed, such as when faced with unforeseen constraints. A multimodal optimization task aims to find multiple global optima as well as high-quality local optima of an optimization problem. Evolutionary algorithms with niching techniques are commonly used for such problems, where a rough estimate of the optima number is required to determine the population size. In this paper, a partition-based random search method is proposed, in which the entire feasible domain is partitioned into smaller and smaller subregions iteratively. Promising regions are partitioned faster than unpromising regions, thus, promising areas will be exploited earlier than unpromising areas. All promising areas are exploited in parallel, which allows multiple good solutions to be found in a single run. The proposed method does not require prior knowledge about the optima number and it is not sensitive to the distance parameter. By cooperating with local search to refine the obtained solutions, the proposed method demonstrates good performance in many benchmark functions with multiple global optima. In addition, in problems with numerous local optima, high-quality local optima are captured earlier than low-quality local optima

Searching for good and diverse game levels

Abstract—In procedural content generation, one is often interested in generating a large number of artifacts that are not only of high quality but also diverse, in terms of gameplay, visual impression or some other criterion. We investigate several search-based approaches to creating good and diverse game content, in particular approaches based on evolution strategies with or without diversity preservation mechanisms, novelty search and random search. The content domain is game levels, more precisely map sketches for strategy games, which are meant to be used as suggestions in the Sentient Sketchbook design tool. Several diversity metrics are possible for this type of content: we investigate tile-based, objective-based and visual impression distance. We find that evolution with diversity preservation mechanisms can produce both good and diverse content, but only when using appropriate distance measures. Reversely, we can draw conclusions about the suitability of these distance measures for the domain from the comparison of diversity preserving versus blind restart evolutionary algorithms. I

Contrôle de caméra virtuelle à base de partitions spatiales dynamiques

Le contrôle de caméra virtuelle est aujourd'hui un composant essentiel dans beaucoup d'applications d'infographie. Malgré cette importance, les approches actuelles restent limitées en terme d'expressivité, d'interactivité et de performances. Typiquement, les éléments de style ou de genre cinématographique sont difficiles à modéliser et à simuler dû à l'incapacité des systèmes actuels de calculer simultanément des points de vues, des trajectoires et d'effectuer le montage. Deuxièmement, elles n'explorent pas assez le potentiel créatif offert par le couplage potentiel d'un humain et d'un système intelligent pour assister les utilisateurs dans une tâche complexe de construction de séquences cinématographiques. Enfin, la plupart des approches existantes se basent sur des techniques d'optimisation dans un espace de recherche 6D, qui s'avèrent coûteuses et donc inadaptées à un contexte interactif. Dans cette thèse, nous proposons tout d'abord un cadre unique intégrant les quatre aspects clés de la cinématographie (le calcul de point de vue, la planification de trajectoires, le montage et la visibilité). Ce cadre expressif permet de simuler certaines dimensions de style cinématographique. Nous proposons ensuite une méthodologie permettant de combiner les capacités d'un système automatique avec une interaction utilisateur. Enfin, nous présentons un modèle de contrôle de caméra efficace qui réduit l'espace de recherche de 6D à 3D. Ce modèle a le potentiel pour remplacer un certain nombre de formulations existantes.Virtual camera control is nowadays an essential component in many computer graphics applications. Despite its importance, current approaches remain limited in their expressiveness, interactive nature and performances. Typically, elements of directorial style and genre cannot be easily modeled nor simulated due to the lack of simultaneous control in viewpoint computation, camera path planning and editing. Second, there is a lack in exploring the creative potential behind the coupling of a human with an intelligent system to assist users in the complex task of designing cinematographic sequences. Finally, most techniques are based on computationally expensive optimization techniques performed in a 6D search space, which prevents their application to real-time contexts. In this thesis, we first propose a unifying approach which handles four key aspects of cinematography (viewpoint computation, camera path planning, editing and visibility computation) in an expressive model which accounts for some elements of directorial style. We then propose a workflow allowing to combine automated intelligence with user interaction. We finally present a novel and efficient approach to virtual camera control which reduces the search space from 6D to 3D and has the potential to replace a number of existing formulations.RENNES1-Bibl. électronique (352382106) / SudocSudocFranceF

Diversified virtual camera composition

Abstract. The expressive use of virtual cameras and the automatic generation of cinematics within 3D environments shows potential to extend the communicative power of films into games and virtual worlds. In this paper we present a novel so-lution to the problem of virtual camera composition based on niching and restart evolutionary algorithms that addresses the problem of diversity in shot generation by simultaneously identifying multiple valid camera camera configurations. We asses the performance of the proposed solution against a set of state-of-the-art algorithms in virtual camera optimisation.