Automatic 3D facial modelling with deformable models.

Facial modelling and animation has been an active research subject in computer graphics since the 1970s. Due to extremely complex biomechanical structures of human faces and peoples visual familiarity with human faces, modelling and animating realistic human faces is still one of greatest challenges in computer graphics. Since we are so familiar with human faces and very sensitive to unnatural subtle changes in human faces, it usually requires a tremendous amount of artistry and manual work to create a convincing facial model and animation. There is a clear need of developing automatic techniques for facial modelling in order to reduce manual labouring. In order to obtain a realistic facial model of an individual, it is now common to make use of 3D scanners to capture range scans from the individual and then fit a template to the range scans. However, most existing template-fitting methods require manually selected landmarks to warp the template to the range scans. It would be tedious to select landmarks by hand over a large set of range scans. Another way to reduce repeated work is synthesis by reusing existing data. One example is expression cloning, which copies facial expression from one face to another instead of creating them from scratch. This aim of this study is to develop a fully automatic framework for template-based facial modelling, facial expression transferring and facial expression tracking from range scans. In this thesis, the author developed an extension of the iterative closest points (ICP) algorithm, which is able to match a template with range scans in different scales, and a deformable model, which can be used to recover the shapes of range scans and to establish correspondences between facial models. With the registration method and the deformable model, the author proposed a fully automatic approach to reconstructing facial models and textures from range scans without re-quiring any manual interventions. In order to reuse existing data for facial modelling, the author formulated and solved the problem of facial expression transferring in the framework of discrete differential geometry. The author also applied his methods to face tracking for 4D range scans. The results demonstrated the robustness of the registration method and the capabilities of the deformable model. A number of possible directions for future work were pointed out

Enhancing Mesh Deformation Realism: Dynamic Mesostructure Detailing and Procedural Microstructure Synthesis

Propomos uma solução para gerar dados de mapas de relevo dinâmicos para simular deformações em superfícies macias, com foco na pele humana. A solução incorpora a simulação de rugas ao nível mesoestrutural e utiliza texturas procedurais para adicionar detalhes de microestrutura estáticos. Oferece flexibilidade além da pele humana, permitindo a geração de padrões que imitam deformações em outros materiais macios, como couro, durante a animação. As soluções existentes para simular rugas e pistas de deformação frequentemente dependem de hardware especializado, que é dispendioso e de difícil acesso. Além disso, depender exclusivamente de dados capturados limita a direção artística e dificulta a adaptação a mudanças. Em contraste, a solução proposta permite a síntese dinâmica de texturas que se adaptam às deformações subjacentes da malha de forma fisicamente plausível. Vários métodos foram explorados para sintetizar rugas diretamente na geometria, mas sofrem de limitações como auto-interseções e maiores requisitos de armazenamento. A intervenção manual de artistas na criação de mapas de rugas e mapas de tensão permite controle, mas pode ser limitada em deformações complexas ou onde maior realismo seja necessário. O nosso trabalho destaca o potencial dos métodos procedimentais para aprimorar a geração de padrões de deformação dinâmica, incluindo rugas, com maior controle criativo e sem depender de dados capturados. A incorporação de padrões procedimentais estáticos melhora o realismo, e a abordagem pode ser estendida além da pele para outros materiais macios.We propose a solution for generating dynamic heightmap data to simulate deformations for soft surfaces, with a focus on human skin. The solution incorporates mesostructure-level wrinkles and utilizes procedural textures to add static microstructure details. It offers flexibility beyond human skin, enabling the generation of patterns mimicking deformations in other soft materials, such as leater, during animation. Existing solutions for simulating wrinkles and deformation cues often rely on specialized hardware, which is costly and not easily accessible. Moreover, relying solely on captured data limits artistic direction and hinders adaptability to changes. In contrast, our proposed solution provides dynamic texture synthesis that adapts to underlying mesh deformations. Various methods have been explored to synthesize wrinkles directly to the geometry, but they suffer from limitations such as self-intersections and increased storage requirements. Manual intervention by artists using wrinkle maps and tension maps provides control but may be limited to the physics-based simulations. Our research presents the potential of procedural methods to enhance the generation of dynamic deformation patterns, including wrinkles, with greater creative control and without reliance on captured data. Incorporating static procedural patterns improves realism, and the approach can be extended to other soft-materials beyond skin

Interdisciplinary Film & Digital Media 2015 APR Self-Study & Documents

UNM Interdisciplinary Film & Digital Media APR self-study report, review team report, response to review report, and initial action plan for Spring 2015, fulfilling requirements of the Higher Learning Commission. IFDM was absorbed by the Cinematic Arts Department following this review

3D Mesh Simplification. A survey of algorithms and CAD model simplification tests

Simplification of highly detailed CAD models is an important step when CAD models are visualized or by other means utilized in augmented reality applications. Without simplification, CAD models may cause severe processing and storage is- sues especially in mobile devices. In addition, simplified models may have other advantages like better visual clarity or improved reliability when used for visual pose tracking. The geometry of CAD models is invariably presented in form of a 3D mesh. In this paper, we survey mesh simplification algorithms in general and focus especially to algorithms that can be used to simplify CAD models. We test some commonly known algorithms with real world CAD data and characterize some new CAD related simplification algorithms that have not been surveyed in previous mesh simplification reviews.Siirretty Doriast

A Consensus on the Definition and Knowledge Base for Computer Graphics

Despite several decades of historical innovation, measurable impacts, and multiple specializations the existing knowledge base for Computer Graphics (CG) lacks consensus, and numerous definitions for it have been published based on distinct contexts. Disagreement among post-secondary academics has divided CG programs into three contextual areas that emphasize different topics. This division has resulted in the decontextualization of CG education, and CG programs now face several challenges in meeting the needs of industry. Employing the Delphi Method, this investigation explored the perceptions among post-secondary educators and industry professionals about the definition of CG and how it is identified in terms of characteristics and context. The outcomes of this investigation identified CG in the technological paradigm, and provided a road map towards a true definition and distinct knowledge base necessary for establishing CG as a formal computing discipline

Realistic simulation and animation of clouds using SkewT-LogP diagrams

Nuvens e clima são tópicos importantes em computação gráfica, nomeadamente na simulação e animação de fenómenos naturais. Tal deve-se ao facto de a simulação de fenómenos naturais−onde as nuvens estão incluídas−encontrar aplicações em filmes, jogos e simuladores de voo. Contudo, as técnicas existentes em computação gráfica apenas permitem representações de nuvens simplificadas, tornadas possíveis através de dinâmicas fictícias que imitam a realidade. O problema que este trabalho pretende abordar prende-se com a simulação de nuvens adequadas para utilização em ambientes virtuais, isto é, nuvens com dinâmica baseada em física que variam ao longo do tempo. Em meteorologia é comum usar técnicas de simulação de nuvens baseadas em leis da física, contudoossistemasatmosféricosdeprediçãonuméricasãocomputacionalmente pesados e normalmente possuem maior precisão numérica do que o necessário em computação gráfica. Neste campo, torna-se necessário direcionar e ajustar as características físicas ou contornar a realidade de modo a atingir os objetivos artísticos, sendo um fator fundamental que faz com que a computação gráfica se distinga das ciências físicas. Contudo, simulações puramente baseadas em física geram soluções de acordo com regras predefinidas e tornam-se notoriamente difíceis de controlar. De modo a enfrentar esses desafios desenvolvemos um novo método de simulação de nuvens baseado em física que possui a característica de ser computacionalmente leve e simula as propriedades dinâmicas relacionadas com a formação de nuvens. Este novo modelo evita resolver as equações físicas, ao apresentar uma solução explícita para essas equações através de diagramas termodinâmicos SkewT/LogP. O sistema incorpora dados reais de forma a simular os parâmetros necessários para a formação de nuvens. É especialmente adequado para a simulação de nuvens cumulus que se formam devido ao um processo convectivo. Esta abordagem permite não só reduzir os custos computacionais de métodos baseados em física, mas também fornece a possibilidade de controlar a forma e dinâmica de nuvens através do controlo dos níveis atmosféricos existentes no diagrama SkewT/LogP. Nestatese,abordámostambémumoutrodesafio,queestárelacionadocomasimulação de nuvens orográficas. Do nosso conhecimento, esta é a primeira tentativa de simular a formação deste tipo de nuvens. A novidade deste método reside no fato de este tipo de nuvens serem não convectivas, oque se traduz nocálculodeoutrosníveis atmosféricos. Além disso, atendendo a que este tipo de nuvens se forma sobre montanhas, é também apresentadoumalgoritmoparadeterminarainfluênciadamontanhasobreomovimento da nuvem. Em resumo, esta dissertação apresenta um conjunto de algoritmos para a modelação e simulação de nuvens cumulus e orográficas, recorrendo a diagramas termodinâmicos SkewT/LogP pela primeira vez no campo da computação gráfica.Clouds and weather are important topics in computer graphics, in particular in the simulation and animation of natural phenomena. This is so because simulation of natural phenomena−where clouds are included−find applications in movies, games and flight simulators. However, existing techniques in computer graphics only offer the simplified cloud representations, possibly with fake dynamics that mimic the reality. The problem that this work addresses is how to find realistic simulation of cloud formation and evolution, that are suitable for virtual environments, i.e., clouds with physically-based dynamics over time. It happens that techniques for cloud simulation are available within the area of meteorology, but numerical weather prediction systems based on physics laws are computationally expensive and provide more numerical accuracy than the required accuracy in computer graphics. In computer graphics, we often need to direct and adjust physical features, or even to bend the reality, to meet artistic goals, which is a key factor that makes computer graphics distinct from physical sciences. However, pure physically-based simulations evolve their solutions according to pre-set physics rules that are notoriously difficult to control. In order to face these challenges we have developed a new lightweight physically-based cloudsimulationschemethatsimulatesthedynamicpropertiesofcloudformation. This new model avoids solving the physically-based equations typically used to simulate the formation of clouds by explicitly solving these equations using SkewT/LogP thermodynamic diagrams. The system incorporates a weather model that uses real data to simulate parameters related to cloud formation. This is specially suitable to the simulation of cumulus clouds, which result from a convective process. This approach not only reduces the computational costs of previous physically-based methods, but also provides a technique to control the shape and dynamics of clouds by handling the cloud levels in SkewT/LogP diagrams. In this thesis, we have also tackled a new challenge, which is related to the simulation oforographic clouds. From ourknowledge, this isthefirstattempttosimulatethis type of cloud formation. The novelty in this method relates to the fact that these clouds are non-convective, so that different atmospheric levels have to be determined. Moreover, since orographic clouds form over mountains, we have also to determine the mountain influence in the cloud motion. In summary, this thesis presents a set of algorithms for the modelling and simulation of cumulus and orographic clouds, taking advantage of the SkewT/LogP diagrams for the first time in the field of computer graphics

All-Women Initiatives in Art and Technology 1986-2020. Atenea: Mentoring and Networking Project in Steam

[ES] La presente tesis doctoral es una exploración sobre las iniciativas auto-organizadas de mujeres que han surgido en la intersección del arte y la tecnología a nivel internacional. Estas iniciativas comunitarias han ido apareciendo en lugares donde existe una escena de arte y nuevos medios, la cual es generalmente de dominación masculina y baja en diversidad. Este trabajo de investigación es un mapeo de este fenómeno tecno-social y artístico, tratando de identificar las primeras prácticas. A través de entrevistas, encuestas y métodos de investigación etnográfica, esta tesis aspira a comprender el contexto que ha dado lugar a semejantes iniciativas a lo largo de tres décadas y media, examinando las diferentes tipologías por los formatos, extensión, espacio y estructura que éstas han adoptado para afrontar la situación de las mujeres en estas áreas. Existe un vació de referencias sobre formas organizativas y de comisariado en las áreas de arte y tecnología. Además, la literatura general señala las subculturas digitales de los noventa, tales como el ciberfeminismo y el movimiento DIY, como los primeros y principales referentes para las alianzas de mujeres y el activismo translocal en la era digital. Sin embargo, las estrategias de colaboración y segregación en áreas de arte y tecnología no han sido analizadas desde los estudios feministas desde una perspectiva histórica en profundidad. Por lo tanto, esta tesis establece la relación entre dichas iniciativas con la historia de los grupos de mujeres artistas y espacios de arte alternativos, la historia de las mujeres en el arte de nuevos medios y la cultura de redes. Las nuevas tecnologías de la información y comunicación han permitido nuevas formas de comunicación y conectividad transfronterizas; sin embargo, este trabajo investiga en qué medida estas iniciativas dependen de las TIC para el establecimiento de su comunidad, comparado con los formatos analógicos. Con los resultados, esta tesis aspira a convertirse en una fuente de referencias que enriquezca la escasa bibliografía de la temática, proporcionando una lista de formas organizativas y de comisariado, así como las practicas más tempranas nunca publicadas, y en conjunto contribuir a la historiografía actual sobre mujeres. Por último, a la vez que se comenta la situación actual de las mujeres en las áreas de arte y tecnología, este trabajo presenta Atenea, un proyecto de mentorización y networking para mujeres en las artes y carreras STEM. Atenea está compuesto de un programa de actividades con diferentes actividades organizativas y de comisariado, así como una plataforma de networking. Adicionalmente, el proyecto tiene un programa enfocado en transmitir conocimientos STEM a niñas a través de prácticas artísticas con tecnología de la mano de mujeres artistas nacionales como mentoras.[CAT] La present tesi doctoral és una exploració sobre les iniciatives autoorganitzades de dones que han sorgit en la intersecció de l'art i la tecnologia a nivell internacional. Aquestes iniciatives comunitàries han anat apareixent en llocs on hi ha una escena d'art i nous mitjans, la qual és generalment de dominació masculina i baixa en diversitat. Aquest treball de recerca és un mapeig d'aquest fenomen tecno-social i artístic, tractant d'identificar les primeres pràctiques. A través d'entrevistes, enquestes i mètodes d'investigació etnogràfica, aquesta tesi aspira a comprendre el context que ha donat lloc a semblants iniciatives al llarg de tres dècades i mig, examinant les diferents tipologies pels formats, extensió, espai i estructura que aquestes han adoptat per afrontar la situació de les dones en aquestes àrees. Hi ha un buit de referències sobre formes organitzatives i de comissariat en les àrees d'art i tecnologia. A més, la literatura general assenyala les subcultures digitals dels noranta, com ara el ciberfeminisme i el moviment DIY, com els primers i principals referents per a les aliances de dones i l'activisme translocal en l'era digital. No obstant això, les estratègies de col·laboració i segregació en àrees d'art i tecnologia no han estat analitzades des dels estudis feministes des d'una perspectiva històrica en profunditat. Per tant, aquesta tesi estableix la relació entre aquestes iniciatives amb la història dels grups de dones artistes i espais d'art alternatius, la història de les dones en l'art de nous mitjans i la cultura de xarxes. Les noves tecnologies de la informació i comunicació han permès noves formes de comunicació i connectivitat transfrontereres; però, aquest treball investiga en quina mesura aquestes iniciatives depenen de les TIC per a l'establiment de la seva comunitat, comparat amb els formats analògics. Amb els resultats, aquesta tesi aspira a convertir-se en una font de referències que enriqueixi l'escassa bibliografia de la temàtica, proporcionant una llista de formes organitzatives i de comissariat, així com les pràctiques més primerenques mai publicades, i en conjunt contribuir a la historiografia actual sobre dones. Finalment, alhora que es comenta la situació actual de les dones en les àrees d'art i tecnologia, aquest treball presenta Atenea, un projecte de mentorització i networking per a dones en les arts i carreres STEM. Atenea està compost d'un programmea d'activitats amb diferents activitats organitzatives i de comissariat, així com una plataforma de networking. Addicionalment, el projecte té un programmea enfocat a transmetre coneixements STEM a nenes a través de pràctiques artístiques amb tecnologia de la mà de dones artistes nacionals com mentores.[EN] This dissertation explores a series of all-women self-organised initiatives that have emerged at the intersection of art and technology internationally. These grassroot initiatives have continued to appear in places where there is a new media arts scene, generally male-dominated and low in diversity. This research work is a mapping of this techno-social and artistic phenomenon, attempting to identify its earliest practices. Through interviews, surveys and ethnographic research, this thesis seeks to comprehend the context that has given rise to such initiatives over three decades and half, examining the different typologies by formats, extension, space and structure that they have adopted to address the situation of women in these fields. There is a void of references on all-women curatorial and organisational forms in art and technology. Moreover, general literature points at digital subcultures of the 1990s such as cyberfeminism and DIY movement as first referents for women's alliance and translocal activism in the digital age. However, collaboration and segregation strategies in new media arts have not been discussed in feminist scholarship from a deeper historical perspective. Therefore, this dissertation elaborates the linkage of such initiatives to early history of all-women art groups and alternative art spaces, history of women in new media arts and to network cultures. New information and communication technologies have enabled new forms of communication and connectivity cross-borders; however, this work investigates in which measure these initiatives are dependent upon ICT for the establishment of a community, compared to analog formats. With the results, this dissertation aims to become a source of references that enriches the scarce bibliography on the topic, providing a list of curatorial and organisational forms with the earliest and unpublished practices that altogether contribute to current women's historiography. Lastly, while discussing the current situation of women in art and technology fields, this works presents Atenea, a mentoring and networking platform for women in Arts and STEM careers. Atenea is comprised of a programme having different organizational, curatorial and networking activities. Additionally, the platform has a project focused on teaching STEM skills to girls through new media arts with female artists as mentors. Keywords: All-women, self-organised, initiatives, new media arts, digital arts, electronic arts, art, technology, activism, mapping, alternative art spaces, collaboration, segregation, ICT, digital age, virtual, community, network cultures, feminism, cyberfeminism, Atenea, STEM, STEAM, girls, organisational, curatorial, networking platform, mentoring,Robles Mateo, E. (2020). All-Women Initiatives in Art and Technology 1986-2020. Atenea: Mentoring and Networking Project in Steam [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/159248TESI

New geometric algorithms and data structures for collision detection of dynamically deforming objects

Any virtual environment that supports interactions between virtual objects and/or a user and objects, needs a collision detection system to handle all interactions in a physically correct or plausible way. A collision detection system is needed to determine if objects are in contact or interpenetrates. These interpenetrations are resolved by a collision handling system. Because of the fact, that in nearly all simulations objects can interact with each other, collision detection is a fundamental technology, that is needed in all these simulations, like physically based simulation, robotic path and motion planning, virtual prototyping, and many more. Most virtual environments aim to represent the real-world as realistic as possible and therefore, virtual environments getting more and more complex. Furthermore, all models in a virtual environment should interact like real objects do, if forces are applied to the objects. Nearly all real-world objects will deform or break down in its individual parts if forces are acted upon the objects. Thus deformable objects are becoming more and more common in virtual environments, which want to be as realistic as possible and thus, will present new challenges to the collision detection system. The necessary collision detection computations can be very complex and this has the effect, that the collision detection process is the performance bottleneck in most simulations. Most rigid body collision detection approaches use a BVH as acceleration data structure. This technique is perfectly suitable if the object does not change its shape. For a soft body an update step is necessary to ensure that the underlying acceleration data structure is still valid after performing a simulation step. This update step can be very time consuming, is often hard to implement and in most cases will produce a degenerated BVH after some simulation steps, if the objects generally deform. Therefore, the here presented collision detection approach works entirely without an acceleration data structure and supports rigid and soft bodies. Furthermore, we can compute inter-object and intraobject collisions of rigid and deformable objects consisting of many tens of thousands of triangles in a few milliseconds. To realize this, a subdivision of the scene into parts using a fuzzy clustering approach is applied. Based on that all further steps for each cluster can be performed in parallel and if desired, distributed to different GPUs. Tests have been performed to judge the performance of our approach against other state-of-the-art collision detection algorithms. Additionally, we integrated our approach into Bullet, a commonly used physics engine, to evaluate our algorithm. In order to make a fair comparison of different rigid body collision detection algorithms, we propose a new collision detection Benchmarking Suite. Our Benchmarking Suite can evaluate both the performance as well as the quality of the collision response. Therefore, the Benchmarking Suite is subdivided into a Performance Benchmark and a Quality Benchmark. This approach needs to be extended to support soft body collision detection algorithms in the future.Jede virtuelle Umgebung, welche eine Interaktion zwischen den virtuellen Objekten in der Szene zulässt und/oder zwischen einem Benutzer und den Objekten, benötigt für eine korrekte Behandlung der Interaktionen eine Kollisionsdetektion. Nur dank der Kollisionsdetektion können Berührungen zwischen Objekten erkannt und mittels der Kollisionsbehandlung aufgelöst werden. Dies ist der Grund für die weite Verbreitung der Kollisionsdetektion in die verschiedensten Fachbereiche, wie der physikalisch basierten Simulation, der Pfadplanung in der Robotik, dem virtuellen Prototyping und vielen weiteren. Auf Grund des Bestrebens, die reale Umgebung in der virtuellen Welt so realistisch wie möglich nachzubilden, steigt die Komplexität der Szenen stetig. Fortwährend steigen die Anforderungen an die Objekte, sich realistisch zu verhalten, sollten Kräfte auf die einzelnen Objekte ausgeübt werden. Die meisten Objekte, die uns in unserer realen Welt umgeben, ändern ihre Form oder zerbrechen in ihre Einzelteile, wenn Kräfte auf sie einwirken. Daher kommen in realitätsnahen, virtuellen Umgebungen immer häufiger deformierbare Objekte zum Einsatz, was neue Herausforderungen an die Kollisionsdetektion stellt. Die hierfür Notwendigen, teils komplexen Berechnungen, führen dazu, dass die Kollisionsdetektion häufig der Performance-Bottleneck in der jeweiligen Simulation darstellt. Die meisten Kollisionsdetektionen für starre Körper benutzen eine Hüllkörperhierarchie als Beschleunigungsdatenstruktur. Diese Technik ist hervorragend geeignet, solange sich die Form des Objektes nicht verändert. Im Fall von deformierbaren Objekten ist eine Aktualisierung der Datenstruktur nach jedem Schritt der Simulation notwendig, damit diese weiterhin gültig ist. Dieser Aktualisierungsschritt kann, je nach Hierarchie, sehr zeitaufwendig sein, ist in den meisten Fällen schwer zu implementieren und generiert nach vielen Schritten der Simulation häufig eine entartete Hüllkörperhierarchie, sollte sich das Objekt sehr stark verformen. Um dies zu vermeiden, verzichtet unsere Kollisionsdetektion vollständig auf eine Beschleunigungsdatenstruktur und unterstützt sowohl rigide, wie auch deformierbare Körper. Zugleich können wir Selbstkollisionen und Kollisionen zwischen starren und/oder deformierbaren Objekten, bestehend aus vielen Zehntausenden Dreiecken, innerhalb von wenigen Millisekunden berechnen. Um dies zu realisieren, unterteilen wir die gesamte Szene in einzelne Bereiche mittels eines Fuzzy Clustering-Verfahrens. Dies ermöglicht es, dass alle Cluster unabhängig bearbeitet werden und falls gewünscht, die Berechnungen für die einzelnen Cluster auf verschiedene Grafikkarten verteilt werden können. Um die Leistungsfähigkeit unseres Ansatzes vergleichen zu können, haben wir diesen gegen aktuelle Verfahren für die Kollisionsdetektion antreten lassen. Weiterhin haben wir unser Verfahren in die Physik-Engine Bullet integriert, um das Verhalten in dynamischen Situationen zu evaluieren. Um unterschiedliche Kollisionsdetektionsalgorithmen für starre Körper korrekt und objektiv miteinander vergleichen zu können, haben wir eine Benchmarking-Suite entwickelt. Unsere Benchmarking- Suite kann sowohl die Geschwindigkeit, für die Bestimmung, ob zwei Objekte sich durchdringen, wie auch die Qualität der berechneten Kräfte miteinander vergleichen. Hierfür ist die Benchmarking-Suite in den Performance Benchmark und den Quality Benchmark unterteilt worden. In der Zukunft wird diese Benchmarking-Suite dahingehend erweitert, dass auch Kollisionsdetektionsalgorithmen für deformierbare Objekte unterstützt werden