Volumetric cloud generation using a Chinese brush calligraphy style

Includes bibliographical references.Clouds are an important feature of any real or simulated environment in which the sky is visible. Their amorphous, ever-changing and illuminated features make the sky vivid and beautiful. However, these features increase both the complexity of real time rendering and modelling. It is difficult to design and build volumetric clouds in an easy and intuitive way, particularly if the interface is intended for artists rather than programmers. We propose a novel modelling system motivated by an ancient painting style, Chinese Landscape Painting, to address this problem. With the use of only one brush and one colour, an artist can paint a vivid and detailed landscape efficiently. In this research, we develop three emulations of a Chinese brush: a skeleton-based brush, a 2D texture footprint and a dynamic 3D footprint, all driven by the motion and pressure of a stylus pen. We propose a hybrid mapping to generate both the body and surface of volumetric clouds from the brush footprints. Our interface integrates these components along with 3D canvas control and GPU-based volumetric rendering into an interactive cloud modelling system. Our cloud modelling system is able to create various types of clouds occurring in nature. User tests indicate that our brush calligraphy approach is preferred to conventional volumetric cloud modelling and that it produces convincing 3D cloud formations in an intuitive and interactive fashion. While traditional modelling systems focus on surface generation of 3D objects, our brush calligraphy technique constructs the interior structure. This forms the basis of a new modelling style for objects with amorphous shape

Measuring user experience for virtual reality

In recent years, Virtual Reality (VR) and 3D User Interfaces (3DUI) have seen a drastic increase in popularity, especially in terms of consumer-ready hardware and software. These technologies have the potential to create new experiences that combine the advantages of reality and virtuality. While the technology for input as well as output devices is market ready, only a few solutions for everyday VR - online shopping, games, or movies - exist, and empirical knowledge about performance and user preferences is lacking. All this makes the development and design of human-centered user interfaces for VR a great challenge. This thesis investigates the evaluation and design of interactive VR experiences. We introduce the Virtual Reality User Experience (VRUX) model based on VR-specific external factors and evaluation metrics such as task performance and user preference. Based on our novel UX evaluation approach, we contribute by exploring the following directions: shopping in virtual environments, as well as text entry and menu control in the context of everyday VR. Along with this, we summarize our findings by design spaces and guidelines for choosing optimal interfaces and controls in VR.In den letzten Jahren haben Virtual Reality (VR) und 3D User Interfaces (3DUI) stark an Popularität gewonnen, insbesondere bei Hard- und Software im Konsumerbereich. Diese Technologien haben das Potenzial, neue Erfahrungen zu schaffen, die die Vorteile von Realität und Virtualität kombinieren. Während die Technologie sowohl für Eingabe- als auch für Ausgabegeräte marktreif ist, existieren nur wenige Lösungen für den Alltag in VR - wie Online-Shopping, Spiele oder Filme - und es fehlt an empirischem Wissen über Leistung und Benutzerpräferenzen. Dies macht die Entwicklung und Gestaltung von benutzerzentrierten Benutzeroberflächen für VR zu einer großen Herausforderung. Diese Arbeit beschäftigt sich mit der Evaluation und Gestaltung von interaktiven VR-Erfahrungen. Es wird das Virtual Reality User Experience (VRUX)- Modell eingeführt, das auf VR-spezifischen externen Faktoren und Bewertungskennzahlen wie Leistung und Benutzerpräferenz basiert. Basierend auf unserem neuartigen UX-Evaluierungsansatz leisten wir einen Beitrag, indem wir folgende interaktive Anwendungsbereiche untersuchen: Einkaufen in virtuellen Umgebungen sowie Texteingabe und Menüsteuerung im Kontext des täglichen VR. Die Ergebnisse werden außerdem mittels Richtlinien zur Auswahl optimaler Schnittstellen in VR zusammengefasst

Constraint-based simulation of virtual crowds

Central to simulating pedestrian crowds is their motion and behaviour. It is required to understand how pedestrians move to simulate and predict scenarios with crowds of people. Pedestrian behaviours enhance the range of motions people can demonstrate, resulting in greater variety, believability, and accuracy. Models with complex computations and motion have difficulty in being extended with additional behaviours. This is because the structure of these models are not designed in a way that is generally compatible with collision avoidance behaviours. To address this issue, this thesis will research a possible pedestrian model that can simulate collision response with a wide range of additional behaviours. The model will do so by using constraints, a limit on the velocity of a person's movement. The proposed model will use constraints as the core computation. By describing behaviours in terms of constraints, these behaviours can be combined with the proposed model. Pedestrian simulations strike a balance between model complexity and runtime speed. Some models focus entirely on the complexity and accuracy of people, while other models focus on creating believable yet lightweight and performant simulations. Believable crowds look realistic to human observation, but do not match up to numerical analysis under scrutiny. The larger the population, and the more complex the motion of people, the slower the simulation will run. One route for improving performance of software is by using Graphical Processing Units (GPUs). GPUs are devices with theoretical performance that far outperforms equivalent multi-core CPUs. Research literature tends to focus on either the accuracy, or the performance optimisations of pedestrian crowd simulations. This suggests that there is opportunity to create more accurate models that run relatively quickly. Real time is a useful measure of model runtime. A simulation that runs in real time can be interactive and respond live to user input. By increasing the performance of the model, larger and more complex models can be simulated. This in turn increases the range of applications the model can represent. This thesis will develop a performant pedestrian simulation that runs in real time. It will explore how suitable the model is for GPU acceleration, and what performance gains can be obtained by implementing the model on the GPU

Virtualidad geolocalizada, proyectos de Realidad Aumentada en el espacio público, propuestas experimentales

[EN] This doctoral thesis aims to make an approach to the area of Public Art and Augmented Reality. To this end, it is essential to understand the changes that have taken place in public space, changes that are linked to the concept of speed of movement, and which have been affected significantly in recent decades with the introduction of new technologies in daily life. Augmented Reality has been formed as an emerging art form. It is a genre in which we find subdivisions according to the technologies employed and the ideas or metaphors to represent by the artists. We understand that in the last decade of economic and social crisis activist involvement is an ethical imperative for the artist. Activism has been and is capable of adapting to the emergence and standardization of several communication technologies to make a critical and artistic use of them. It is able to break the classic barrier between the real and the virtual while providing a positive overcoming of the conflicts that the system generates in its post-industrial age like the atomization and alienation of the citizen, as well as the processes as much from constitution of ghettos that are isolated urbanistically as from the gentrification in several districts of the current cities. In this respect, a catalog of works related to the use of Augmented Reality technologies in the artistic activism is proposed. The empirical experimentation and practical production turns out to be, likewise, necessary to approach the theoretical parameters proposed in this thesis. For this reason our work has been focused on the implementation of artistic specific projects, which allow us to demonstrate this relation between the Public Art and the Augmented Reality. A relation that shows us simultaneously, the new typology of human relations and alternative topographies of the city that are generated in the public hybrid space, increasing its accessibility to citizens and overcoming the artist-active / audience-passive dichotomy through the contextual practice and the situationist drift through the different works that we have proposed. This practice establishes a new democratizing vector of the art that, therefore, allows the civil participation in other artistic closed circles which transmute into a constellation of decentralized interconnected nodes like artistic participative rhizome in which the citizenship can express creatively in all their dimensions.[ES] La presente tesis pretende realizar una aproximación al campo del Arte Público y la Realidad Aumentada. Para ello resulta imprescindible comprender los cambios acontecidos en el espacio público, cambios que van ligados al concepto de velocidad de movimiento, y que se han visto afectados significativamente en las ultimas décadas con la implantación de las nuevas tecnologías en la vida cotidiana. La Realidad Aumentada se ha conformado como un género artístico emergente. Un género en el que podemos encontrar subdivisiones en función de las tecnologías empleadas y de las ideas o metáforas a representar por los artistas. Entendemos que en esta última década de crisis económica y social la implicación activista resulta un imperativo ético para el artista. Pues el activismo ha sido y es capaz de adaptarse al surgimiento y estandarización de diversas tecnologías de comunicación para hacer un uso crítico-artístico de las mismas capaz de romper la barrera clásica entre lo real y lo virtual al tiempo que propone una superación positiva de los conflictos que genera el sistema en su era pos-industrial como son la atomización y alienación del ciudadano, así como los procesos tanto de constitución de guetos aislados urbanísticamente como de gentrificación en diversos distritos de las ciudades actuales. En este sentido, se propone una catalogación de obras relacionadas con la utilización de tecnologías de Realidad Aumentada dentro del activismo artístico. Resulta, así mismo, necesaria la experimentación empírica y producción práctica para abordar los parámetros teóricos propuestos en esta tesis, por lo que nuestro trabajo se ha centrado en la implementación de proyectos artísticos concretos, que permiten evidenciar esta relación entre el Arte Público y la Realidad Aumentada. Una relación que nos muestra a un tiempo, la nueva tipología de relaciones humanas y topografías alternativas de la urbe que se generan en el espacio público híbrido, aumentando su accesibilidad a la ciudadanía y superando la dicotomía artista-activo / público-pasivo mediante la práctica contextual y la deriva situacionista a través de las diferentes obras que hemos propuesto. Práctica que recorre un nuevo vector democratizador del arte, que por ende permite la participación ciudadana en círculos artísticos cerrados, que transmutan en una constelación de nodos descentralizados interconexionados a modo de rizoma artístico participativo, en el que la ciudadanía puede expresarse creativamente en toda su magnitud.[CA] La present tesi pretén realitzar una aproximació al camp de l'Art Públic i la Realitat Augmentada. Per açò resulta imprescindible comprendre els canvis esdevinguts en l'espai públic, canvis que van lligats al concepte de velocitat de moviment, i que s'han vist afectats significativament en les últimes dècades amb la implantació de les noves tecnologies en la vida quotidiana. La Realitat Augmentada s'ha conformat com un gènere artístic emergent. Un gènere en el qual podem trobar subdivisions en funció de les tecnologies emprades i de les idees o metàfores a representar pels artistes. Entenem que en aquesta última dècada de crisi econòmica i social la implicació activista resulta un imperatiu ètic per a l'artista. Doncs l'activisme ha sigut i és capaç d'adaptar-se al sorgiment i estandardització de diverses tecnologies de comunicació per a fer un ús crític-artístic de les mateixes, capaç de trencar la barrera clàssica entre el real i el virtual al mateix temps que proposa una superació positiva dels conflictes que genera el sistema en la seua era post-industrial com són l'atomització i alienació del ciutadà, així com els processos tant de constitució de guetos aïllats urbanísticament com de gentrificació en diversos districtes de les ciutats actuals. En aquest sentit, es proposa una catalogació d'obres relacionades amb la utilització de tecnologies de Realitat Augmentada dins de l'activisme artístic. Resulta, així mateix, necessària l'experimentació empírica i producció pràctica per a abordar els paràmetres teòrics proposats en aquesta tesi, per la qual cosa el nostre treball s'ha centrat en la implementació de projectes artístics concrets, que permeten evidenciar aquesta relació entre l'Art Públic i la Realitat Augmentada. Una relació que ens mostra a un temps, la nova tipologia de relacions humanes i topografies alternatives de la urbs que es generen en l'espai públic híbrid, augmentant la seua accessibilitat a la ciutadania i superant la dicotomia artista-actiu / públic-passiu mitjançant la pràctica contextual i la deriva situacionista a través de les diferents obres que hem proposat. Pràctica que recorre un nou vector democratitzador de l'art que per tant permet la participació ciutadana en els altres cercles artístics tancats que transmuten en una constel·lació de nodes descentralitzats interconnectats a manera de rizoma artístic participatiu en el qual la ciutadania pot expressar-se creativament en tota la seua magnitud.Ferrer Hernández, M. (2016). Virtualidad geolocalizada, proyectos de Realidad Aumentada en el espacio público, propuestas experimentales [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/61771TESI