15,832 research outputs found
Player communities in multiplayer online games: A systematic review of emperical research
No full textNumerous researchers have written about the social dynamics of player communities in multiplayer online games. Following a systematic review of refereed empirical research publications from 2000-2010, this article synthesizes the key methods and concepts researchers have used to study and characterize player communities, as well as the aspects and operationalizations they have concentrated on. The analysis shows that qualitative approaches have been more popular than quantitative. The concepts used to characterize player communities were often not clearly defined or overlapped in meaning. Yet they revealed a prevalence of micro (groups or teams), meso (guilds or organizations) and macro (communities and networks) perspectives. Eighteen different aspects and operationalizations of player communities were identified. Six of these were clearly most popular, i.e. social structuring, rationale, culture & social norms, sed ICTs, number of members and time of existence. The article concludes with several perspectives and suggestions for future research.Multi Actor SystemsTechnology, Policy and Managemen
Towards Social Behavior in Virtual-Agent Navigation
Full text linkWe present Social Groups and Navigation (SGN), a method to simulate the walking behavior of small pedestrian groups in virtual environments. SGN is the first method to simulate group behavior on both global and local levels of an underlying planning hierarchy. We define quantitative metrics to measure the coherence and the sociality of a group based on existing empirical data of real crowds. SGN does not explicitly model coherent and social formations, but it lets such formations emerge from simple geometric rules. In addition to a previous version, SGN also handles group-splitting to smaller groups throughout navigation as well as social sub-group behavior whenever a group has to temporarily split up to re-establish its coherence. For groups of four, SGN generates between 13% and 53% more socially-friendly behavior than previous methods, measured over the lifetime of a group in the simulation. For groups of three, the gain is between 15% and 31%, and for groups of two, the gain is between 1% and 4%. SGN is designed in a flexible way, and it can be integrated into any crowd-simulation framework that handles global path planning and any path following as separate steps. Experiments show that SGN enables the simulation of thousands of agents in real time
Perception of Complex Emotional Body Language of a Virtual Character
No full textVirtual characters are a common phenomenon in serious game applications, and can enrich training environments for a range of different purposes. These characters can be used in games that have been developed to help people with learning difficulties. They can also be used to help users develop social skills, such as communication. For social interactions, much communicative information is contained in the body language between the parties involved. We know that humans are sensitive to emotions when they are conveyed on a virtual character and are capable of correctly identifying certain emotions. However, research on emotions and virtual characters tends to focus on a small number of emotions. We wish to create characters for a serious game who will convey a wide range of complex and subtle emotions. This paper presents a first investigation into the use of complex emotional body language for a virtual character. In two experiments, we examine participants’ perception of a range of motion-captured subtle emotions. Results from a pilot shows that participants are better able to recognise complex emotions with negative connotations rather than positive from a virtual character’s body motion. A second experiment aims to identify perceptual overlaps in these emotions, and results obtained motivate further investigation
Real-Time Density-Based Crowd Simulation
No full textVirtual characters in games and simulations often need to plan visually convincing paths through a crowded environment. This paper describes how crowd density information can be used to guide a large number of characters through a crowded environment. Crowd density information helps characters avoid congested routes that could lead to traffic jams. It also encourages characters to use a wide variety of routes to reach their destination. Our technique measures the desirability of a route by combining distance information with crowd density information. We start by building a navigation mesh for the walkable regions in a polygonal 2D or multi-layered 3D environment. The skeleton of this navigation mesh is the medial axis. Each walkable region in the navigation mesh maintains an up-to-date density value. This density value equals the area of all characters inside a given region divided by the total area of this region. These density values are mapped onto the medial axis to form a weighted graph. An A* search on this graph yields a backbone path for each character, and forces are used to guide the characters through the weighted environment. The characters periodically replan their routes as the density values are updated. Our experiments show that we can compute congestion-avoiding paths for tens of thousands of characters in real-time
Towards a playful organization ideal-type: Values of a playful organizational culture
No full textNumerous organizations have embarked on playful endeavors such as serious gaming (playing games with a learning/training purpose) and ‘gamification’ (applying game technology and principles to make existing practices more game-like). One could consequently theorize about the dawn of playful or anizations, i.e. a type of organization that is culturally and structurally playful. This article offers a first step towards a playful organization theory. It specifically offers a conceptual framework of a playful organizational culture. Following a review of play theory as well as organization and management theory that was inspired by play, the author describes a playful organizational culture as encompassing contingency, opportunism, equivalence, instructiveness, meritocracy and onviviality as values. The framework offers leaders, managers and game/play designers opportunities to further develop playful endeavors for organizations. It also offers social scientists opportunities to further research the emergence and issues of playful organizations.Multi Actor SystemsTechnology, Policy and Managemen
Path Planning for Groups using Column Generation
No full textIn computer games, one or more groups of units need to move from one location to another as quickly as possible. If there is only one group, then it can be solved efficiently as a dynamic flow problem. If there are several groups with different origins and destinations, then the problem becomes -hard. In current games, these problems are solved by using greedy ad hoc rules, leading to long traversal times or congestions and deadlocks near narrow passages. We present a centralized optimization approach based on Integer Linear Programming. Our solution provides an efficient heuristic to minimize the average and latest arrival time of the units
Mapping the Discipline of the Olympic Games An Author-Cocitation Analysis
Full text linkThe authors conducted an author cocitation analysis on prominent authors writing about the Olympics during the 1990s. Author cocitation is an established bibliometric technique that can be used to measure the relative similarities of topics written about by the cited authors. This enables a visual representation of the “intellectual space” of the discipline, in this case the Olympics, to be created for the period under review. So core and peripheral research areas are identified, along with their major contributors. The representation appears as a two-dimensional cluster-enhanced map. Subject expertise was then applied to the results to place labels on the generated clusters of authors and their topics
Injury Assessment for Physics-Based Characters
No full textDetermining injury levels for virtual characters is an important aspect of many games. For characters that are animated using simulated physics, it is possible assess injury levels based on physical properties, such as accelerations and forces. We have constructed a model for injury assessment that relates results from research on human injury response to parameters in physics-based animation systems. We describe a set of different normalized injury measures for individual body parts, which can be combined into a single measure for total injury. Our research includes a user study in which human observers rate the injury levels of physics-based characters falling from varying heights at different orientations. Results show that the correlation between our model output and perceived injury is stronger than the correlation between perceived injury and fall height (0.603 versus 0.466, respectively, with N = 1020 and p
Motion Planning for Human Crowds: from Individuals to Groups of Virtual Characters
No full textVirtual worlds, to become more lively and appealing, are typically populated by large crowds of virtual characters. One of the fundamental tasks that these characters have to perform is, on one hand, to plan their paths between different locations in the world and, on the other hand, to move toward their desired locations in a human-like manner avoiding collisions with each other and with the environment. This is the main topic of this thesis. Although the path planning problem has received considerable attention over the past thirty years, most path planning algorithms originate from robotics aiming at creating short and collision-free paths for one or a few robots having many degrees of freedom. In interactive virtual worlds, though, the requirements are different. Paths for hundreds of characters through complex environments should be planned simultaneously and in real-time using only a small percentage of the CPU time. In addition to being collision-free, the paths followed by the characters must also look plausible in order to retain the suspension of disbelief of the viewer. Such paths typically follow smooth curves, are short and keep a certain amount of clearance to obstacles. To address the aforementioned issues, in the first part of the thesis, we introduce the Indicative Route Method as a new path planning approach in interactive virtual worlds and games. We further combine the Indicative Route Method with techniques from Linear Programming to efficiently choreograph through space-time the motions of large heterogeneous groups of virtual characters. We also present simple techniques for creating variants of homotopic paths that virtual characters can follow given a path planning query. Such variation not only provides a more challenging and less predictable opponent for the user in a (serious) game, but also enhances the realism of a simulation allowing the characters to spread over the environment and take alternative routes. Besides demonstrating believable path planning behavior, the virtual characters should also be able to adapt their motions resolving a bewildering amount of local interactions and avoiding collisions with each other. This problem is very challenging, since real humans exhibit behaviors of enormous complexity and subtlety making their simulation a rather difficult task. In the second part of the thesis, we try to address some of these challenges. We first propose a physically-based model for solving interactions between virtual pedestrians that have converging trajectories. The proposed method is extremely fast, simple to implement and captures the emergence of self-organization phenomena allowing interactions to be solved more efficiently at a global scale. We also address the issue of realistic collision avoidance among virtual humans by exploiting experimental interactions data between real pedestrians. In the derived model, virtual characters take early and effort-efficient actions to avoid collisions by slightly adapting their directions and speeds. We further extend this technique to simulate the walking behavior of small groups of virtual pedestrians. Here, a novel algorithm is introduced ensuring that the group members will safely navigate toward their goals, while forming walking patterns similar to the ones observed in real-life
Multisensory perception of spatial orientation and self-motion
No full textThe aim of this project was to improve our insight in how the brain combines information from different sensory systems (e.g. vestibular and visual system) into an integrated percept of self-motion and spatial orientation. Based on evidence from other research in different areas, such as hand-eye coordination, we hypothesized that the human brain takes the reliability of the individual sensory cues into account when estimating the body’s motion and orientation in the environment. This mechanism is called “maximum likelihood integration” (MLI), in which the brain attributes the most weight to the sensory cues with the least variance. This integration results in a statistically optimal percept: it is the most precise estimate possible given the sensory cues. The results were not always consistent with the hypothesis of MLI. For example, the first two simulator experiments showed little evidence that MLI applies to the integration of visual and vestibular information of the direction of linear self-motion. Multisensory judgments (with visual and vestibular cues available) were not more precise than unisensory judgments (with only visual or vestibular information). One of the contributing factors was the limited realism of the synthetic visual stimulus, which may have caused a perceptual dissociation between the visual and vestibular motion. On the other hand, we did find supporting evidence that information from the two vestibular subsystems, i.e. the semi-circular canals and the otoliths, is combined in a statistically optimal fashion. Normally, tilting the head stimulates both the semi-circular and otoliths together. Hence it is difficult to stimulate the otoliths in isolation. In a carefully designed experiment in the DESDEMONA simulator we created unisensory stimulation of the otoliths by using centrifugation, and unisensory stimulation of the semi-circular canals by rotating the subjects while they were lying supine. The multisensory condition comprised normal self-tilt from an upright position. The results agreed with the MLI model. Finally, we participated in the first European Partial Gravity Parabolic Flight Campaign organized by the European Space Agency (ESA), to study the perception of self-tilt under partial gravity conditions: weightlessness (0g), Lunar gravity (0.16g), and Martian gravity (0.38g). This provided a unique opportunity to manipulate the magnitude of gravity, which on Earth is always fixed. Although the data did not provide conclusive evidence of MLI in the integration of visual and vestibular cues, we did the remarkable finding that gravity must exceed a certain threshold value before it is being recognized as reference for vertical. Below this threshold, gravity may be felt as a force, but does not serve as a reference for orientation. The recognition threshold is individually determined and seems to increase with subjects’ age. The older subjects (40+ years) did no longer recognize the direction of “up” under Martian gravity, whereas the younger subjects (under 40) lost their feeling for “up” when gravity was reduced to Lunar levels. This corresponds to reports of the Apollo astronauts having great difficulties in judging the slope of the terrain while exploring the surface of the Moo
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