L'animation expressive permet des styles de mouvements exagerés et artistiques comme l'étirement de parties du corps ou encore l'animation de créatures imaginaires comme un dragon. Créer ce genre d'animation nécessite des outils assez flexible afin de déformer les personnages en des poses quelconques, ainsi que de pouvoir contrôler l'animation à tout moment dans le temps. L'approche acutelle pour l'animation expressive est le keyframing: une approche manuelle avec laquelle les animateurs déforment leur personnage un moment spécifique dans le temps en cliquand et glissant la souris sur une partis spécifique du corps---un à la fois. Malgré le fait que cette approche soit flexible, il est difficile de créer des animations de qualité qui suivent les principes artistiques, puisque le keyframing permet seulement qu'un contrôle local spatiallement et temporellement. Lorsqu'ils dessinent des poses ou des mouvements, les artistes s'appuient sur différentes abstractions sous forme de croquis qui facillitent la réalisation de certain principes artistiques. Par example, certains animateurs dessinent des lignes d'action afin de créer une pose plus lisible et expressive. Afin de coordonner un mouvement, les animateurs vont souvent dessiner des abstractions de mouvement comme des demi-cercles pour des sauts, ou des boucles pour des pirouettes---leur permettant de pratiquer la coordination du mouvement. Malheureusement, ces outils artistiques ne font pas partis de l'ensemble d'outils de keyframing actuelle. Le fait que l'on ne puisse pas employer les même outils artistiques pour animater des personnages 3D a une forte conséquence: les outils d'animation 3D ne sont pas employés dans le processus créatif. Aujourd'hui, les animateurs créent sur du papier et utilisent le keyframing seulement à la fin pour réaliser leur animation. La raison pour laquelle nous n'avons pas ces outils artistiques (ligne d'action, abstractions de mouvement) en animation 3D, est parce qu'il manque une compréhension formelle de ceux-ci qui nous permettrais d'exprimer la forme du personnage---potentiellement au cours du temps---en fonction de la forme de ces croquis. Ainsi la contribution principale de cette thèse est une compréhension formelle et mathématique des abstractions de forme et de mouvement courrament employées par des artistes, ainsi qu'un ensemble d'algorithme qui permet l'utilisation de ces outils artistiques pour créer des animations expressives. C'est-à-dire que les outils développés dans cette thèse permettent d'étirer des parties du corps ainsi que d'animer des personnages de différentes morphologies. J'introduis aussi plusieurs extentions à ces outils. Par example, j'explore l'idée de sculpter du mouvement en permettant à l'artiste de dessigner plusieurs couches de mouvement une par dessus l'autre, de twister en 3D les croquis, ou encore d'animer un croquis ligne comme un élastique. Les contributions principales de cette thèse, aussi résumé ci-dessous: -La ligne d'action facilitant la création de poses expressives en dessinant directement le flow complet du personnage. -La courbe spatio-temporelle qui permet de spécifier un mouvement coordoné complet avec un seul geste (en dessinant une seule courbe), applicable à n'importe quel personnage 3D. -Un algorithme de matching rapide et robuste qui permet du ``squash and stretch''. -La ligne d'action élastique avec des attachements dynamiques à la ligne permettant d'animer un personnages à plusieurs jambes (bras) avec une seule ligne 2D animée. / Free-form animation allows for exaggerated and artistic styles of motions such as stretching character limbs and animating imaginary creatures such as dragons. Creating these animations requires tools flexible enough to shape characters into arbitrary poses, and control motion at any instant in time. The current approach to free-form animation is keyframing: a manual task in which animators deform characters at individual instants in time by clicking-and-dragging individual body parts one at a time. While this approach is flexible, it is challenging to create quality animations that follow high-level artistic principles---as keyframing tools only provide localized control both spatially and temporally. When drawing poses and motions, artists rely on different sketch-based abstractions that help fulfill high-level aesthetic and artistic principles. For instance, animators will draw textit{lines of action} to create more readable and textit{expressive} poses. To coordinate movements, animators will sketch textit{motion abstractions} such as semi-circles and loops to coordinate a bouncing and rolling motions. Unfortunately, these drawing tools are not part of the free-form animation tool set today. The fact that we cannot use the same artistic tools for drawing when animating 3D characters has an important consequence: 3D animation tools are not involved in the creative process. Instead, animators create by first drawing on paper, and only later are 3D animation tools used to fulfill the pose or animation. The reason we do not have these artistic tools (the line of action, and motion abstractions) in the current animation tool set is because we lack a formal understanding relating the character's shape---possible over time---to the drawn abstraction's shape. Hence the main contribution of this thesis is a formal understanding of pose and motion abstractions (line of action and motion abstractions) together with a set of algorithms that allow using these tools in a free-form setting. As a result, the techniques described in this thesis allow exaggerated poses and movements that may include squash and stretch, and can be used with various character morphologies. These pose and animation drafting tools can be extended. For instance, an animator can sketch and compose different layers of motion on top of one another, add twist around strokes, or turning the strokes into elastic ribbons. The main contributions of this thesis are summarized as follows: -The line of action facilitating expressive posing by directly sketching the overall flow of the character's pose. -The space-time curve allowing to draft full coordinated movements with a single stroke---applicable to arbitrary characters. -A fast and robust skeletal line matching algorithm that supports squash-and-stretch. -Elastic lines of action with dynamically constrained bones for driving the motion of a multi-legged character with a single moving 2D line.

L'animation expressive permet des styles de mouvements exagerés et artistiques comme l'étirement de parties du corps ou encore l'animation de créatures imaginaires comme un dragon. Créer ce genre d'animation nécessite des outils assez flexible afin de déformer les personnages en des poses quelconques, ainsi que de pouvoir contrôler l'animation à tout moment dans le temps. L'approche acutelle pour l'animation expressive est le keyframing: une approche manuelle avec laquelle les animateurs déforment leur personnage un moment spécifique dans le temps en cliquand et glissant la souris sur une partis spécifique du corps---un à la fois. Malgré le fait que cette approche soit flexible, il est difficile de créer des animations de qualité qui suivent les principes artistiques, puisque le keyframing permet seulement qu'un contrôle local spatiallement et temporellement. Lorsqu'ils dessinent des poses ou des mouvements, les artistes s'appuient sur différentes abstractions sous forme de croquis qui facillitent la réalisation de certain principes artistiques. Par example, certains animateurs dessinent des lignes d'action afin de créer une pose plus lisible et expressive. Afin de coordonner un mouvement, les animateurs vont souvent dessiner des abstractions de mouvement comme des demi-cercles pour des sauts, ou des boucles pour des pirouettes---leur permettant de pratiquer la coordination du mouvement. Malheureusement, ces outils artistiques ne font pas partis de l'ensemble d'outils de keyframing actuelle. Le fait que l'on ne puisse pas employer les même outils artistiques pour animater des personnages 3D a une forte conséquence: les outils d'animation 3D ne sont pas employés dans le processus créatif. Aujourd'hui, les animateurs créent sur du papier et utilisent le keyframing seulement à la fin pour réaliser leur animation. La raison pour laquelle nous n'avons pas ces outils artistiques (ligne d'action, abstractions de mouvement) en animation 3D, est parce qu'il manque une compréhension formelle de ceux-ci qui nous permettrais d'exprimer la forme du personnage---potentiellement au cours du temps---en fonction de la forme de ces croquis. Ainsi la contribution principale de cette thèse est une compréhension formelle et mathématique des abstractions de forme et de mouvement courrament employées par des artistes, ainsi qu'un ensemble d'algorithme qui permet l'utilisation de ces outils artistiques pour créer des animations expressives. C'est-à-dire que les outils développés dans cette thèse permettent d'étirer des parties du corps ainsi que d'animer des personnages de différentes morphologies. J'introduis aussi plusieurs extentions à ces outils. Par example, j'explore l'idée de sculpter du mouvement en permettant à l'artiste de dessigner plusieurs couches de mouvement une par dessus l'autre, de twister en 3D les croquis, ou encore d'animer un croquis ligne comme un élastique. Les contributions principales de cette thèse, aussi résumé ci-dessous: -La ligne d'action facilitant la création de poses expressives en dessinant directement le flow complet du personnage. -La courbe spatio-temporelle qui permet de spécifier un mouvement coordoné complet avec un seul geste (en dessinant une seule courbe), applicable à n'importe quel personnage 3D. -Un algorithme de matching rapide et robuste qui permet du ``squash and stretch''. -La ligne d'action élastique avec des attachements dynamiques à la ligne permettant d'animer un personnages à plusieurs jambes (bras) avec une seule ligne 2D animée. / Free-form animation allows for exaggerated and artistic styles of motions such as stretching character limbs and animating imaginary creatures such as dragons. Creating these animations requires tools flexible enough to shape characters into arbitrary poses, and control motion at any instant in time. The current approach to free-form animation is keyframing: a manual task in which animators deform characters at individual instants in time by clicking-and-dragging individual body parts one at a time. While this approach is flexible, it is challenging to create quality animations that follow high-level artistic principles---as keyframing tools only provide localized control both spatially and temporally. When drawing poses and motions, artists rely on different sketch-based abstractions that help fulfill high-level aesthetic and artistic principles. For instance, animators will draw textit{lines of action} to create more readable and textit{expressive} poses. To coordinate movements, animators will sketch textit{motion abstractions} such as semi-circles and loops to coordinate a bouncing and rolling motions. Unfortunately, these drawing tools are not part of the free-form animation tool set today. The fact that we cannot use the same artistic tools for drawing when animating 3D characters has an important consequence: 3D animation tools are not involved in the creative process. Instead, animators create by first drawing on paper, and only later are 3D animation tools used to fulfill the pose or animation. The reason we do not have these artistic tools (the line of action, and motion abstractions) in the current animation tool set is because we lack a formal understanding relating the character's shape---possible over time---to the drawn abstraction's shape. Hence the main contribution of this thesis is a formal understanding of pose and motion abstractions (line of action and motion abstractions) together with a set of algorithms that allow using these tools in a free-form setting. As a result, the techniques described in this thesis allow exaggerated poses and movements that may include squash and stretch, and can be used with various character morphologies. These pose and animation drafting tools can be extended. For instance, an animator can sketch and compose different layers of motion on top of one another, add twist around strokes, or turning the strokes into elastic ribbons. The main contributions of this thesis are summarized as follows: -The line of action facilitating expressive posing by directly sketching the overall flow of the character's pose. -The space-time curve allowing to draft full coordinated movements with a single stroke---applicable to arbitrary characters. -A fast and robust skeletal line matching algorithm that supports squash-and-stretch. -Elastic lines of action with dynamically constrained bones for driving the motion of a multi-legged character with a single moving 2D line.

Humanos virtuais são modelos computacionais de pessoas. Se necessário, podem apresentar uma aparência bastante realista, baseada em princípios fisiológicos e biomecânicos. Além disso, são capazes de comportar-se de forma autônoma e inteligente em ambientes dinâmicos, podendo apresentar até mesmo individualidade e personalidade. Humanos virtuais podem ser utilizados como atores sintéticos. Tais atores têm sido usados em uma série de aplicações com a finalidade de simular a presença de atores reais. A indústria de jogos por computador requer personagens que sejam capazes de reagir apropriadamente a eventos e circunstâncias inesperadas, e até mesmo de alterar o progresso do jogo com seus cursos de ação autônomos. Um modo natural para desenvolver tais personagens prevê o uso de técnicas de inteligência artificial, em particular aquelas relacionadas às áreas de agentes autônomos e sistemas multiagentes. Neste trabalho, propõese o uso do modelo BDI (Belief-Desire-Intention) para modelar agentes cognitivos, com a finalidade de implementar personagens animados. O modelo BDI é uma abordagem bastante conhecida e bem sucedida para o desenvolvimento de agentes autônomos em sistemas multiagentes. Trata-se de uma arquitetura poderosa para sistemas dinâmicos e complexos, nos quais agentes podem precisar agir sob informação incompleta e incorreta sobre o seu ambiente e os outros habitantes. Esta dissertação reúne um modelo articulado para animação de personagens, o qual requer a especificação de movimento em cada junta individualmente, e um interpretador para AgentSpeak(L), uma linguagem de programação orientada a agentes que implementa a arquitetura BDI. Foi desenvolvida uma interface que permite que o sistema de raciocínio de um agente, baseado em BDI, seja usado para dirigir o comportamento de um personagem em um sistema de animação. O uso de AgentSpeak(L) é uma abordagem promissora para a especificação em alto nível de animações complexas por computador. O modelo conceitual e sua implementação são apresentados em capítulos distintos. Esta separação visa simplificar a compreensão do modelo proposto, permitindo primeiro analisá-lo em um nível mais alto de abstração, para então verificar detalhes de programação. Este trabalho apresenta também duas animações 3D, usadas para ilustrar a abordagem proposta. A principal animação apresentada envolve um agente situado em um ambiente dinâmico; o agente continuamente percebe o ambiente e raciocina para determinar como agir sobre ele, baseado em seu estado mental BDI. A outra aplicação é bastante simples, mas útil para mostrar algumas questões que são relevantes para obter-se mais eficiência em programas AgentSpeak(L). / Virtual humans are computational models of people. If necessary, they can portray a very realistic appearance, based on biomechanical and physiological principles. Besides, they are able to behave in an autonomous and intelligent way in dynamic environments, and even to exhibit individuality and personality. Virtual humans can be used as synthetic actors. Such kind of actors have been used in several applications, such as games, in order to simulate the presence of real actors. The computer-game industry requires characters that are able to react appropriately to unexpected events and circumstances, and even to change the game progress with their autonomous courses of actions. A natural way for developing such characters is by the use of artificial intelligence techniques, in particular those related to the areas of autonomous agents and multi-agent systems. In this work, the use of the Belief-Desire-Intention (BDI) model for cognitive agents in order to implement animated characters is proposed. The BDI model is a well-known and successful approach for the development of autonomous agents in multiagent systems. It is a very powerful architecture for dynamic and complex systems where agents may need to act under incomplete and incorrect information on other agents and their environment. This work brings together an articulated model for character animation, which requires the specification of motion on each joint individually, and an interpreter for AgentSpeak(L), an agent-oriented programming language that implements the BDI architecture. I have developed an interface that allows the BDI-based agent reasoning system to be used for guiding the behaviour of a character in an animation system. The use of AgentSpeak(L) is a promising approach for the high-level specification of complex computer animations. The conceptual model and its implementation are presented in distinct chapters. This separation aims at simplifying the comprehension of the proposed model, allowing its analysis first at a higher abstraction level, and after that to check programming details. This work also presents two 3-D animations used to illustrate the proposed approach. The main animation presented involves an agent that is situated in a dynamic environment; the agent continuously perceives the environment and reasons on how to act upon it based on its BDI mental state. The other application is quite simple, but useful to show some issues that are relevant for obtaining better performance from AgentSpeak(L) programs.

Humanos virtuais são modelos computacionais de pessoas. Se necessário, podem apresentar uma aparência bastante realista, baseada em princípios fisiológicos e biomecânicos. Além disso, são capazes de comportar-se de forma autônoma e inteligente em ambientes dinâmicos, podendo apresentar até mesmo individualidade e personalidade. Humanos virtuais podem ser utilizados como atores sintéticos. Tais atores têm sido usados em uma série de aplicações com a finalidade de simular a presença de atores reais. A indústria de jogos por computador requer personagens que sejam capazes de reagir apropriadamente a eventos e circunstâncias inesperadas, e até mesmo de alterar o progresso do jogo com seus cursos de ação autônomos. Um modo natural para desenvolver tais personagens prevê o uso de técnicas de inteligência artificial, em particular aquelas relacionadas às áreas de agentes autônomos e sistemas multiagentes. Neste trabalho, propõese o uso do modelo BDI (Belief-Desire-Intention) para modelar agentes cognitivos, com a finalidade de implementar personagens animados. O modelo BDI é uma abordagem bastante conhecida e bem sucedida para o desenvolvimento de agentes autônomos em sistemas multiagentes. Trata-se de uma arquitetura poderosa para sistemas dinâmicos e complexos, nos quais agentes podem precisar agir sob informação incompleta e incorreta sobre o seu ambiente e os outros habitantes. Esta dissertação reúne um modelo articulado para animação de personagens, o qual requer a especificação de movimento em cada junta individualmente, e um interpretador para AgentSpeak(L), uma linguagem de programação orientada a agentes que implementa a arquitetura BDI. Foi desenvolvida uma interface que permite que o sistema de raciocínio de um agente, baseado em BDI, seja usado para dirigir o comportamento de um personagem em um sistema de animação. O uso de AgentSpeak(L) é uma abordagem promissora para a especificação em alto nível de animações complexas por computador. O modelo conceitual e sua implementação são apresentados em capítulos distintos. Esta separação visa simplificar a compreensão do modelo proposto, permitindo primeiro analisá-lo em um nível mais alto de abstração, para então verificar detalhes de programação. Este trabalho apresenta também duas animações 3D, usadas para ilustrar a abordagem proposta. A principal animação apresentada envolve um agente situado em um ambiente dinâmico; o agente continuamente percebe o ambiente e raciocina para determinar como agir sobre ele, baseado em seu estado mental BDI. A outra aplicação é bastante simples, mas útil para mostrar algumas questões que são relevantes para obter-se mais eficiência em programas AgentSpeak(L). / Virtual humans are computational models of people. If necessary, they can portray a very realistic appearance, based on biomechanical and physiological principles. Besides, they are able to behave in an autonomous and intelligent way in dynamic environments, and even to exhibit individuality and personality. Virtual humans can be used as synthetic actors. Such kind of actors have been used in several applications, such as games, in order to simulate the presence of real actors. The computer-game industry requires characters that are able to react appropriately to unexpected events and circumstances, and even to change the game progress with their autonomous courses of actions. A natural way for developing such characters is by the use of artificial intelligence techniques, in particular those related to the areas of autonomous agents and multi-agent systems. In this work, the use of the Belief-Desire-Intention (BDI) model for cognitive agents in order to implement animated characters is proposed. The BDI model is a well-known and successful approach for the development of autonomous agents in multiagent systems. It is a very powerful architecture for dynamic and complex systems where agents may need to act under incomplete and incorrect information on other agents and their environment. This work brings together an articulated model for character animation, which requires the specification of motion on each joint individually, and an interpreter for AgentSpeak(L), an agent-oriented programming language that implements the BDI architecture. I have developed an interface that allows the BDI-based agent reasoning system to be used for guiding the behaviour of a character in an animation system. The use of AgentSpeak(L) is a promising approach for the high-level specification of complex computer animations. The conceptual model and its implementation are presented in distinct chapters. This separation aims at simplifying the comprehension of the proposed model, allowing its analysis first at a higher abstraction level, and after that to check programming details. This work also presents two 3-D animations used to illustrate the proposed approach. The main animation presented involves an agent that is situated in a dynamic environment; the agent continuously perceives the environment and reasons on how to act upon it based on its BDI mental state. The other application is quite simple, but useful to show some issues that are relevant for obtaining better performance from AgentSpeak(L) programs.

Motion capture is the process of capturing movements from real life into a computer. Existing motion capture systems are often very expensive and require advanced hardware that makes the process complex. This thesis will answer the following question: is it possible to create an optical motion capture system using only a single low cost Dvcamera (Digital Video Camera), that still will produce accurate motion capture data? To answer this question and construct our motion capture system we need to complete these following steps: • Create a usable film sequence. • Analyze the sequence. • Create motion capture data. • Apply the motion capture data for 3D character and analyze the outcome. The method chosen for this thesis is constructive research. In short terms it is the study of whether we can or cannot build a new artifact. The following theoretic tools were used in the process of creating a motion capture system: Color theory, RGB, Connected component labeling, Skeletons in 3D animation, Calculating angels using trigonometry, .x files and Quaternions. We have found that an optical motion capture system is very complex and it is hard to produce as a low budget system. Our attempt did not live up to our expectations. The idea with using only one DV camera was to simplify the system since it would require no calibration or syncronisation. It would also make the system cost efficient and more available to the general public. The single camera solution unfortunatly created a number of problems in our system. Our system does however work with less complex movements. It can produce motion capture data that is accurate enough to be used in low budget games. It is also cost effective compared to other systems on the market. The system has a very easy setup and does not need any calibration in addition to the init position.

Humanos virtuais são modelos computacionais de pessoas. Se necessário, podem apresentar uma aparência bastante realista, baseada em princípios fisiológicos e biomecânicos. Além disso, são capazes de comportar-se de forma autônoma e inteligente em ambientes dinâmicos, podendo apresentar até mesmo individualidade e personalidade. Humanos virtuais podem ser utilizados como atores sintéticos. Tais atores têm sido usados em uma série de aplicações com a finalidade de simular a presença de atores reais. A indústria de jogos por computador requer personagens que sejam capazes de reagir apropriadamente a eventos e circunstâncias inesperadas, e até mesmo de alterar o progresso do jogo com seus cursos de ação autônomos. Um modo natural para desenvolver tais personagens prevê o uso de técnicas de inteligência artificial, em particular aquelas relacionadas às áreas de agentes autônomos e sistemas multiagentes. Neste trabalho, propõese o uso do modelo BDI (Belief-Desire-Intention) para modelar agentes cognitivos, com a finalidade de implementar personagens animados. O modelo BDI é uma abordagem bastante conhecida e bem sucedida para o desenvolvimento de agentes autônomos em sistemas multiagentes. Trata-se de uma arquitetura poderosa para sistemas dinâmicos e complexos, nos quais agentes podem precisar agir sob informação incompleta e incorreta sobre o seu ambiente e os outros habitantes. Esta dissertação reúne um modelo articulado para animação de personagens, o qual requer a especificação de movimento em cada junta individualmente, e um interpretador para AgentSpeak(L), uma linguagem de programação orientada a agentes que implementa a arquitetura BDI. Foi desenvolvida uma interface que permite que o sistema de raciocínio de um agente, baseado em BDI, seja usado para dirigir o comportamento de um personagem em um sistema de animação. O uso de AgentSpeak(L) é uma abordagem promissora para a especificação em alto nível de animações complexas por computador. O modelo conceitual e sua implementação são apresentados em capítulos distintos. Esta separação visa simplificar a compreensão do modelo proposto, permitindo primeiro analisá-lo em um nível mais alto de abstração, para então verificar detalhes de programação. Este trabalho apresenta também duas animações 3D, usadas para ilustrar a abordagem proposta. A principal animação apresentada envolve um agente situado em um ambiente dinâmico; o agente continuamente percebe o ambiente e raciocina para determinar como agir sobre ele, baseado em seu estado mental BDI. A outra aplicação é bastante simples, mas útil para mostrar algumas questões que são relevantes para obter-se mais eficiência em programas AgentSpeak(L). / Virtual humans are computational models of people. If necessary, they can portray a very realistic appearance, based on biomechanical and physiological principles. Besides, they are able to behave in an autonomous and intelligent way in dynamic environments, and even to exhibit individuality and personality. Virtual humans can be used as synthetic actors. Such kind of actors have been used in several applications, such as games, in order to simulate the presence of real actors. The computer-game industry requires characters that are able to react appropriately to unexpected events and circumstances, and even to change the game progress with their autonomous courses of actions. A natural way for developing such characters is by the use of artificial intelligence techniques, in particular those related to the areas of autonomous agents and multi-agent systems. In this work, the use of the Belief-Desire-Intention (BDI) model for cognitive agents in order to implement animated characters is proposed. The BDI model is a well-known and successful approach for the development of autonomous agents in multiagent systems. It is a very powerful architecture for dynamic and complex systems where agents may need to act under incomplete and incorrect information on other agents and their environment. This work brings together an articulated model for character animation, which requires the specification of motion on each joint individually, and an interpreter for AgentSpeak(L), an agent-oriented programming language that implements the BDI architecture. I have developed an interface that allows the BDI-based agent reasoning system to be used for guiding the behaviour of a character in an animation system. The use of AgentSpeak(L) is a promising approach for the high-level specification of complex computer animations. The conceptual model and its implementation are presented in distinct chapters. This separation aims at simplifying the comprehension of the proposed model, allowing its analysis first at a higher abstraction level, and after that to check programming details. This work also presents two 3-D animations used to illustrate the proposed approach. The main animation presented involves an agent that is situated in a dynamic environment; the agent continuously perceives the environment and reasons on how to act upon it based on its BDI mental state. The other application is quite simple, but useful to show some issues that are relevant for obtaining better performance from AgentSpeak(L) programs.

Background. Secondary motion is a principle of animation, it is movement that occurs as a result of other movement, such as swinging hair or clothes. In 3D animation, such as in games, it is often simulated instead of animated manually. In game projects with time limitations, it can be interesting to know to what degree these simulations impact the visual quality in order to decide whether they should be prioritized. It is also interesting to know how the results of various methods compare to each other. To simulate in real-time means that physics simulations are running during gameplay. Baked animations on the other hand are simulations that have already been processed and saved as animation data, they are less dynamic but also less performance intensive. Objectives. The aim of this thesis is to evaluate the impact of three sets of animations by conducting a survey where each set is compared. The three sets are: animations that feature real-time simulations, baked simulations and ones without simulation. The goal is to acquire a metric from the comparisons that can give an insight to the visual quality impact of each method. Methods. Three animation sets were created. Then, a survey was conducted using a questionnaire that featured side by side video comparisons of the animation sets. The videos featured a stylized character running, walking, or jumping through an empty environment. Pairwise similarity judgements were done by asking the participants to rate each video compared to each other. The results from the questionnaire were analyzed using a method that is a part of the analytical hierarchy process. The data from each comparison was averaged, put into pairwise comparison matrices, and then used to calculate priority vectors. The level of consistency of the comparisons were also calculated. Results. The priority vectors show the ratios of how each animation set were preferred compared to each other. In the priority vector for all animations combined, the set without simulations ranked at twenty-four percent, the real-time set ranked at thirty-three percent and the baked set ranked the highest at forty-three percent. The comparisons were calculated to have a very high consistency, which strengthens the result. Conclusions. The results show the impact that adding simulated secondary motion has. The simulations appear to improve the visual quality, but the margin is not extreme. The calculated ratios could be used to argue for or against a game project’s prioritization of secondary motion simulations depending on the project’s time constraints and access to preexisting methods of simulation. It should be noted that the format of video comparisons did not showcase all the advantages of each method such as creation accessibility, technical performance or dynamicity. As such, it is uncertain how fair the comparisons of the baked and real-time simulations are in a more general sense. Nevertheless, the results are considered to give at least a partial insight into how these methods compare.

程序式動畫是一種根據使用者所提供的高階運動參數，自動產生動畫的方法。藉著高階的運動參數，程序式動畫比運動擷取資料有著更高的彈性。使用者可透過調整參數，輕易地讓動畫滿足情境上所需的限制。但如何調整適當的運動參數以產生擬真的動畫仍屬不易，因此程序式動畫常有在視覺上觀感不自然的問題。本研究的目標是，將運動擷取資料擬真的要素，帶到程序式動畫之中，以改進程序式動畫的品質。我們將問題定義成一個最佳化問題：給定一段運動擷取資料，系統該如何調整程序式動畫之參數，使得程序式動畫與運動擷取資料的差距盡可能地縮小？我們的系統可以參考一段運動擷取資料，以最佳化演算法，自動調整程序式動畫的參數，搜尋能產生出與運動擷取資料最為相似的運動參數。為了進一步讓產生之動畫符合環境的限制需求，多組最佳化過後的運動參數可以再透過內插，重新產生出一組符合限制需求的運動參數。實驗結果顯示，我們的方法不但使程序式動畫得以保留原來彈性的優點，也改善了程序式動畫常有的視覺觀感不自然的缺點。 / Procedural animation provides a way for a user to generate animation according to the high-level motion parameters that the user supplies. With the high-level motion parameters, procedural animation has the flexibility of generating animation accommodating the requested constraints in a scenario. However, tuning parameters to generate realistic animations usually is a difficult task. Therefore, animations produced with this approach often have the drawback of unrealistic-looking. Our goal is to improve the quality of procedural animation by bringing the naturalness of motion capture data into procedural animation. We model our problem as an optimization problem: given a motion captured clip, how does the system tune the motion parameters in an animation procedure to minimize the difference between animations produced by a procedure and captured in a motion clip? Our proposed system takes a motion captured clip as a reference and tunes the motion parameters of the animation procedure with an optimization algorithm. In order to generate animation satisfying environmental constraints, multiple optimized motion parameters can be interpolated to create a new set of motion parameters which can also satisfy the constraints. Our experimental results show that our method not only retains the flexibility of procedural animation, but also enhances the quality of procedural animation.

動作擷取法是現今相當受到歡迎的角色動作產生方法，而一般多是使用已擷取好的動作，以人工的方式將數個不同的動作混合以產生出所需的動作。但想要大量產生符合需求的混合動作仍相當不容易，因此有人提出了「動作圖」這個方法。動作圖是一種根據使用者所給定的動作擷取資料集合，經過自動化的計算找出各個動作資料之間可以連接的動作片段。藉由這個自動化的程序，各個動作擷取資料可以相互連接起來，達到在不同的動作間平順轉換，且同時保有原動作擷取資料擬真特性的目的。但縱使有上述的好處，目前動作圖的技術僅能就所擷取的全身動作進行串接，品質與彈性往往決定於一開始動作擷取資料的準備，因此如何讓既有的全身動作資料得以分解再利用，以發揮最大的價值，是一個重要的問題。在本研究中，我們提出了一個階層式的動作圖結構名為多層式動作圖，在這個多層式動作圖的結構中，我們將身體的動作區分成數個部位，分別計算各自的動作圖後再合併成一個多層式的架構，而合併的過程中我們提出「整體動作相似度」的計算方式，以做為兩個動作是否容易轉接的比較依據。我們也提出了在不同階層間動作圖運作的規則，以使計算的複雜度及系統的可用性取得合理的平衡。此外，我們更進一步提出名為Motion Script的簡易語意描述語言，來輔助控制這個具有高複雜度的動作圖結構。實驗的結果顯示，我們的方法可以即時根據使用者的指令，搜尋並產生出原動作資料所沒有的動作組合。與傳統的動作圖相比，我們的方法能更進一步的發揮原動作擷取資料的價值，以有系統的方式讓動作組合自動產生更具豐富性及彈性。 / Motion capture is a popular method for generating realistic character animation. In most applications, a motion usually is prepared by manually blending existing captured motion clips to generate a desired motion clip. However, finding a good transition points manually for two motion clips is a time-consuming task and cannot be scaled up easily. Motion Graph is a technique that has been proposed to automate this process by finding suitable connection points and the corresponding transition motions between motion data. With this automatic procedure, motions captured separately can be smoothly connected while keeping the realism of the captured motions. However, most motion graph techniques only consider the transition of full-body motions in two motion clips, and therefore, the resulting motion .depends on the variety of motions available in the motion database. It is an important issue to be able to compose new motion clips as much as possible with given motion capture database. In this research, we propose a hierarchical motion graph structure called Multi-Layered Motion Graph. In this structure, we divide motion data into layers of parts depending on the articulated structure of human body, and then compute a motion graph for each part of the motion. We then combine these motion graphs into an interconnected hierarchical structure. In order to facilitate the composition of motions for different parts from different motion clips, we propose a new metric called Overall Motion Similarity to find reasonable composition of motions in run time. We also propose several rules about how to traverse the motion graphs in different layers to generate feasible motions. Furthermore, we have designed a scripting language called Motion Script to facilitate the specification and search of desirable animation to be generated. Our experimental results reveal that our method is able to compose animations that the original motion graph cannot generate in real time. Compared to the traditional motion graph method, our method is able to make good use of existing motion capture library to compose new motions in a systematic way.

In aspiration to achieve naturalistic character animation, some difficulty does show up, both in 3D-CGI, 2D-CGI as in traditional handmade animation. The reason why difficulty appears in the task of achieving naturalism is for instance because of the simulated natural laws in the digital world which cannot affect the characters cinematic movement. The result of illustrating the natural law manually by hand can affect the illusion of the movement as not naturalistic or inconsistent, which can result in that the spatial adaptation to space is not perceived as naturalistic. It is most often up to the animator to make a believable illusion of the natural laws. This study examines a deeper understanding of the human way to behave and to adapt to the physical reality and through that, apply this movement on character animation. The purpose of a deeper understanding of movement's phenomena is to find a clearer method dedicated to naturalistic movement that can be adapted to all forms of character animation, regardless of the character anatomy. Unfortunately, it would not be possible to study all aspects of the physically adaptive behaviors as to the size of the topic. This study will therefore orbit the human locomotion, also known as walking. Focus will therefore be on the bottom part of the body, from the pelvis down to the ankles. There are scientists that do argue about a connection between the golden ratio and the human locomotion. This study is an attempt to apply the golden ratio on 3D-characters. This study has been devoted to a different approach in the character animation, where its starting point will be mathematical equations. For this study, it has meant an application of the golden section in a temporary form, that is in motion. The result is therefore a mathematically based method dedicated to imitating naturalistic movement in terms of time, that is to say human locomotion. The method has been proved to be useful even in the imitation of characters movements that do not possess human proportions. / I en strävan efter naturalistisk karaktäranimation uppstår vissa hinder på vägen i 3D-CGI som 2D-CGI animation. Svårigheter i att uppnå naturalism beror bland annat på att det inte finns några simulerade naturlagar i den digitala världen som kan påverka karaktärens kinematiska rörelser. Resultatet av att behöva illustrera naturlagar och liknande externa påverkningar manuellt för hand kan orsaka en rumslig känsla om onaturlighet eller inkonsekvens. Vilket kan resultera i att den rumsliga anpassningen till rummet inte upplevs som naturalistisk. Ofta är det upp till animatören att skapa en trovärdig illusion om naturlagarna. Målet med denna studie är att utforska och ge animatören en djupare förståelse för människans sätt att förhålla och anpassa sig till den fysiska verkligheten. Syftet med en djupare förståelse för rörelsers företeelser är att finna en tydligare metod dedikerad åt naturalistisk rörelse som går att anpassa för alla former av karaktärsanimation, oberoende av karaktärens anatomi. Tyvärr skulle det inte vara möjligt att täcka alla aspekter av det fysiskt adaptiva beteendet på grund av ämnets storlek. Denna studie har därför avgränsats till mänsklig lokomotion, även känt som vandring. Fokus riktas därför mot bäckenet och knäleden ner till anklarna. Det finns forskning som argumenterar för en koppling mellan det gyllene snittet och mänskliga rörelser. Denna studie är ett försök att tillämpa lokomotion uträknat ifrån gyllene snittet på en digital tredimensionell karaktär. Denna studie har ägnats ett annorlunda angreppsätt i karaktärsanimationen där dess utgångspunkt består av matematiska ekvationer. Det har för studien inneburit ett applicerande av gyllene snittet i en temporär form, det vill säga i rörelse. Resultatet är därför en matematiskt baserad metod dedikerad för att efterlikna naturalistisk rörelse i form av gång, alltså mänsklig lokomotion. Metoden har visat sig användbar även vid efterliknandet av karaktärers rörelser som inte besitter mänskliga proportioner.