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1.FP.C - Análise de Tecnologias para a Implementação de Jogos Web [open]
Rangel Jungles dos Santos (Universidade Federal do Paraná)
André Battaiola (Universidade Federal do Paraná)
Este artigo aborda as questões mais relevantes na produção de jogos single-players baseados na Web. Apresenta as razões que motivam o estudo desse tipo de aplicação, indica os requisitos mínimos de tecnologia necessários para sua elaboração, relata as características daquelas que são consideradas as tecnologias emergentes para a produção desse tipo de software e propõe um conjunto de estratégias para superar os problemas encontrados no uso de um pacote composto por três delas (Extensible 3D (X3D) com Xj3D, Flash e JavaScript / ECMAScript).

2.FP.C - A New Programming Environment for Dynamics-based Animation [open]
Leonardo Oliveira (Universidade Federal de Mato Grosso do Sul)
Paulo Pagliosa (Universidade Federal de Mato Grosso do Sul)
This paper presents a new animation system initially designed for visualization of dynamics simulations in science and engineering applications. A hybrid language is used to describe the scene objects to be animated and the scripts and actions that modify the state of the objects over time. The system is made up of components responsible to compile and execute an animation, and render and exhibit the resulting frames. Currently, the animation system is being extended to support dynamic simulations of rigid and elastic bodies in interactive, real-time applications, including games. For rigid body simulations, AGEIA PhysX engine is used as a component. The paper presents the functionality of the main components of the original system architecture, introduces the main features of the animation language and describes how an animation is specified and then executed by the system.

3.FP.C - An Architecture for Game State Management based on State Hierarchies [open]
Luis Valente (Universidade Federal Fluminense)
Aura Conci (UFF)
Bruno Feijó (PUC-Rio)
Computer games can be regarded as state machines as far as their stages are concerned. The traditional design for this state machine is to assign ids to the states and to use conditional constructs to direct the game execution to the proper state. However, this approach is not robust enough and can quickly get out of control. This work proposes an object-oriented model to state specification and management, which features state hierarchies.

4.FP.C - An Object-Oriented Approach for Hierarchical State Machines [open]
William Mallouk (IMPA/Wet Productions)
Esteban Clua  (PUC-Rio)
Finite State Machines have been widely used as a tool for developing video games, being mostly employed to solve problems such as AI, input handling, and game progression. In this paper we introduce a practical technique that can highly improve the productivity at the development of FSMs in video games. This technique consists of adapting concepts of OOP for use with Hierarchical Finite State Machines in an entirely visual system. It is also presented an open-source implementation of the technique that can be used as middleware in most games.
 
5.FP.C - ARHockey: Um Jogo em Realidade Aumentada Baseada em Projetores [open]
Beatriz Vieira (Centro Universitário Senac)
Lucas Trias (Centro Universitário SENAC)
Camila Theodoro (Centro Universitário Senac)
Fabio Roberto Miranda (Centro Universitário Senac)
Romero Tori (SENAC-SP / Universidade de Sao Paulo
This works presents the design and implementation of a projector-based augmented reality version of the game known as air hockey or shufflepuck, commonly find in arcade halls and malls. Projector-based AR allows a larger number of people to take part in a game because theres no need for individual visualization equipment, and opens up interesting possibilities for the game developer by allowing dynamic changes in some of the game elements, that would not be possible in the real game.

6.FP.C - Camera Kombat - Interação Livre para Jogos [open]
Luis Roberto Paula (Centro Universitário Senac)
Renato Bonini (Centro Universitário Senac)
Fabio Roberto Miranda (Centro Universitário Senac
This work presents details of the creation of Camera Kombat, a two-player game that allows users to participate in an unemcumbered way, without the mediation of traditional input devices, such as joysticks, mouses and keyboards. In order to enable this level of interaction, computer vision techniques are used to recognize gestures in images of the user captured by a webcam.

7.FP.C - enJine: Architecture and Application of an Open-Source Didactic Game Engine [open]
Ricardo Nakamura (Escola Politécnica - USP)
João Bernardes Jr. (University of Sao Paulo)
Romero Tori (SENAC-SP / Universidade de Sao Paulo)
In this paper we present enJine, an open-source didactic game engine, its architecture and some results of applying it as a support tool for teaching Computer Graphics in a computer engineering course. The evolution of the engines requisites and architecture is discussed, as well as the plans for future development of the software.

8.FP.C - GeFighters: an Experiment for Gesture-based Interaction Analysis in a Fighting Game [open]
João Marcelo Teixeira (Centro de Informática - UFPE)
Thiago Farias (Universidade Federal de Pernambuco)
Guilherme Moura (UFPE)
João Lima (Federal University of Pernambuco)
Saulo Pessoa (UFPE)
Veronica Teichrieb (Universidade Federal de Pernambuco)
This paper presents GeFighters, a 3D fighting game that supports gesture based interaction. This application has been used to test and analyze gesture interaction in the context of games that need short and reliable response times. Some inherent aspects of the application will be analyzed, like the impact that interaction causes on frame renderization and response time related to the control of game characters. In order to implement the desired interaction, an input devices management platform, named CIDA, has been used.

9.FP.C - Guffs Character Animation System for 3D Games and Applications [open]
Marcio Camilo (Universidade Federal Fluminense)
Aura Conci (UFF)
3D Games frameworks usually have some type of Character Animation System based on a low level layer for animations and a high level layer related with the behavior and intelligence of characters. The low level is responsible for providing a way of obtaining animations and to play them correctly and suitable according to the needs of the high level. This paper presents the implementation of the low level layer of the Guff Framework. This system provides functionalities for obtaining animations based on the Doom3s MD5 models and the possibility of a fine tune post-design configuration stage, which allows designers to set groups of animations for supplying the high level animation system, animation-to-animation transitions and animations properties such as uniformity, evolution and timing. Finally, a first approach to a high level animation system, based in a very simple finite state machine, was developed to show how the low level animation system can support the high level animation system.

10.FP.C - Improving the Scene: Extending LOGTELL to Support a Plan-recognition / Plan-generation Paradigm [open]
Börje Karlsson (PUC-Rio)
Cesar T. Pozzer (Universidade Federal de Santa Maria)
Angelo E. M. Ciarlini (UNIRIO)
Antonio L. Furtado (POUC-Rio)
Bruno Feijó (PUC-Rio)
How to characterize a literary genre is a much debated problem, which can be approached with useful results by combining models drawn from both Literary Theory and Computer Science. Once a genre is specified with some rigour in a constructive way, it becomes possible not only to determine whether a given plot is a legitimate representative of the genre, but also to generate such plots, an ability of obvious relevance to Storytelling theory and practice. A key issue in interactive storytelling is how to generate stories which are, at the same time, interesting and coherent. On the one hand, it is desirable to provide means for the user to intervene in the story. But, on the other hand, it is necessary to guarantee that user intervention will not introduce events that violate the rules of the intended genre. A conceptual modelling method with the purpose of allowing an interactive narrative is presented, based on a plan recognition/plan generation paradigm. The method leads to the formulation of static, dynamic and behavioural schemas, expressed in temporal logic, and to a multi-stage interactive plot generation, supported by a logic-based tool for the interactive generation and dramatization of stories. This paper describes extensions made to the LOGTELL prototype to better support the genre model and incorporate a plan recognition / plan generation paradigm. The resulting system is of special help for the composition of plots through the adaptation of fully or partially generated plots. A case study, involving a simple Swords and Dragons genre (also extended), illustrates the discussion. Based on the model, the user can interact with the tool at various levels, obtaining a variety of stories agreeable to individual tastes, within the imposed coherence requirements. The system alternates stages of goal inference, planning, plan recognition, user intervention and 3D visualization.

11.FP.C - Jogadores Virtuais em Jogos de Papéis [open]
Diana Adamatti (Universidade de Sao Paulo)
Jaime Sichman (USP - Universidade de São Paulo)
Helder Coelho (Universidade de Lisboa)
This paper proposes the insertion of Virtual Players in GMABS (Games and Multi-Agent-Based Simulation) methodology, to support negotiation process in conflicts resolution. This methodology uses Multi-Agent-Based Simulation (MABS) and Role-Playing Games (RPG) techniques in integrated way. Firstly, we defined a generic architecture for virtual players in GMABS and after, we implemented a prototype to this architecture.

12.FP.C - Massive Mobile Games Porting: Meantime Study Case [open]
Tarcísio P. Câmara (Meantime Mobile Creations)
Rodrigo B. V. Lima (Meantime Mobile Creations)
Rangner F. Guimarães (Meantime Mobile Creations)
Alexandre L.G. Damasceno (Meantime Mobile Creations)
Vander R. Alves (UFPE)
Pedro H. Macedo (Meantime Mobile Creations)
Geber L. Ramalho (UFPE)
Game development for mobile devices is usually regarded as a simpler task when compared to games developed for desktop platforms. Indeed, the resources provided by the latter do support more complex applications, therefore, increasing the final product value, and also making the development cycle longer. Although mobile games (and mobile applications, in general) do not have the same amount of resources to be explored, they must adhere to a very strong portability requirement and, since the whole development cycle is rather short, this porting phase must be as efficient and cheap as possible, so that it does not have a huge impact on the final product. In this present work, we will discuss Meantime’s experience in developing and porting J2ME games to a large amount of different devices, elucidating how we have evolved from an immature porting process up to a new process that has proved to be more scalable, efficient, cheaper and easier to maintain.

13.FP.C - Massive Mobile Porting: Meantime Study Case [open]
Tarcísio P. Câmara (UFPE)
Rodrigo B. V. Lima (Meantime Mobile Creations)
Rangner F. Guimarães (Meantime Mobile Creations)
Alexandre L.G. Damasceno (CESAR)
Vander R. Alves(UFPE)
Pedro H. Macedo (Meantime Mobile Creations)
Geber L. Ramalho (UFPE)
Game development for mobile devices is usually regarded as a simpler task when compared to games developed for desktop platforms. Indeed, the resources provided by the latter do support more complex applications, therefore, increasing the final product value, and also making the development cycle longer. Although mobile games (and mobile applications, in general) do not have the same amount of resources to be explored, they must adhere to a very strong portability requirement and, since the whole development cycle is rather short, this porting phase must be as efficient and cheap as possible, so that it does not have a huge impact on the final product. In this present work, we will discuss Meantimes experience in developing and porting J2ME games to a large amount of different devices, elucidating how we have evolved from an immature porting process up to a new process that has proved to be more scalable, efficient, cheaper and easier to maintain.

14.FP.C - Modelo de Comunicação Híbrido para Jogos Massivos Multi-jogador [open]
Solon Rabello (UNISINOS - Universidade do Vale do Rio dos Sinos)
Fabio Cecin (UFRGS)
Jorge Barbosa (Unisinos)
Claudio Geyer (UFRGS)
Este artigo apresenta uma técnica de comunicação de dados para jogos de ação em tempo real, usando de forma híbrida os modelos cliente-servidor e ponto-a-ponto. Baseado parcialmente na réplica de simuladores, tem como objetivo suportar a computação descentralizada de sessões de jogo de pequena escala, sendo essas instâncias (espaços de ação) resistentes às trapaças de conluio (Collusion cheat). Esses espaços de ação são unidos pelo espaço social, que é o estado persistente do servidor suportando alta escalabilidade. Juntos, esses dois tipos de espaços dão suporte aos jogos massivos multi-jogador (MMOGs) através da união de espaços sociais persistentes e centralizados com espaços de ação de pequena escala, temporários e descentralizados. Nesse modelo os nodos dos jogadores são os responsáveis pela execução simultânea da simulação conservadora e da otimista. Será mostrado que em média 2,2 simulações simultâneas são executadas por passo e que a média dos máximos das simulações por passo é 11,95 para sessões de teste de 20 jogadores com lag de rede entre 150ms e 300ms, possuindo 5% de probabilidade do atraso de eventos introduzir erros, e tendo a computação de rollbacks e de execuções corretivas diluída em 100ms, ou mais, de tempo real.

15.FP.C - Motion Capture Facial Baseado em Aquisição Estereoscópica [open]
Rodrigo Assaf (Federal University of São Carlos)
José Saito (Universidade Federal de São Carlos
Facial animation has been widely used in many areas of applications and entertainment, presenting high levels of details and technology. However, its implementation still demands lots of hard work from the producer team. Aiming at the adaptation of a stereoscopic system to a financial low cost facial animation system, this research is based on facial control points on a human face, which is 3D modeled using the box modeling technique. The 3D virtual face is used to apply an ending result of a facial expression, or lip sync, obtained from the methods of stereoscopy, association and interpolation.

16.FP.C - Multiagent exploration task in games through negotiation [open]
Rodrigo Gabriel F. Soares (UFRN)
André M. C. Campos (UFRN)
When a group of characters in a game aim to efficiently explore an environment, it is important that they coordinate their actions to cooperatively discover new areas. This paper tackles the exploration task as a multi-agent problem in the context of computer games. Four simple strategies and an auction-based negotiation strategy were implemented and evaluated. Their performance was compared in different scenarios according to a set of metrics proposed in the paper. It was so possible to figure out an efficient strategy for random scenario. A simulator has also been developed in order to perform the necessary tests.

17.FP.C - Narrating Stories in Participatory Games [open]
Paula Rodrigues (PUC-Rio)
Bruno Feijó (PUC-Rio)
Luiz Velho (IMPA)
Cesar T. Pozzer (Universidade Federal de Santa Maria
Angelo Ciarlini (UniRio)
Antonio Furtado (PUC-Rio
Interaction and participation are in the kernel of the new medium of games. The ultimate goal is the participatory game, where interactive games and storytelling are merged. One of the most complex forms of this type of game is the narrated ones. This paper presents an architecture that incorporates a virtual narrator, capable of emotional expressions synchronized with speech, to an interactive storytelling system, in order to create a new form of participatory game, in which the player is co-author of the plot.

18.FP.C - One Scenario for Choreographic Coordination of Intelligent Agents in Entertainment Applications [open]
Rodrigo B. V. Lima (UFPE)
Patrícia A. Restelli Tedesco (UFPE)
Geber L. Ramalho (UFPE)
Most researches in agent coordination for computer games focus on tactical/spatial coordination of NPCs (Non Playable Characters) seeking effective methods for accomplishing a collective task in the context of war games, FPS (First Person Shooters) and RTS (Real Time Startegy) (e.g., [Almeida et al. 2004; Madeira et al. 2005; Marthi et al. 2005]). Some research efforts have been employed to make the movements of group of agents more realistic and pleasant [Messick 1999; Reynolds 1999]. However, the aesthetic aspect plays a secondary role in the complexity of the task the group of agents must accomplish. This work represents a step forward towards a deeper concern on the aesthetic/choreographic dimension that may arise from the NPCs interactions. Based on a framework for supporting multi-agent choreographic coordination [Lima et al. 2005], we present an original entertainment application, named DiscoTech, where agents reason, communicate and coordinate with each other in order to form groups and perform choreographies

19.FP.C - Selected Techniques to Improve Communication in Massively Multiplayer Games [open]
Lucas Machado (PUC-Rio)
Bruno Feijó (PUC-Rio)
Lauro Kozovits (PUC-Rio)
There are no papers or books in the literature that analyze the most suitable techniques to improve communication in massively multiplayer games in a detailed and implementation-oriented way. Most of the results and recommendations in this area are buried in proprietary systems and classified documentation. Based on experiments in the VLab/IGame Laboratory, this paper presents selected techniques and practical recommendations for the development of Massively Multiplayer Games. Optimization techniques in the use of sockets are given. Technologies capable of handling many sockets at once are explained. Also techniques for optimizing communication in virtual environments are presented.

20.FP.C - Serviços de Adaptação de Jogabilidade para Jogos Multiplataforma Multiusuario [open]
Fernando Trinta (Universidade Federal de Pernambuco)
Carlos André Guimarães Ferraz (UFPE)
Geber Ramalho (Universidade Federal de Pernambuco)
Davi Pedrosa (Universidade Federal de Pernambuco)
This paper presents a particular view for future Networked Multiplayer Games. These applications will include features from pervasive computing, allowing players to enjoy them using different devices, such as PDAs and Mobile Phones, almost anywhere, anytime. These games demand player´s playability to be adapted according context information, such as player´s location and device. In this document, we call these applications Pervasive Multiplayer Multiplatform Games (PM2G). We present sceneries that show intended characteristics for these games. From these sceneries, we developed two models, an Application Model and an Usage Model. The former introduces specific PM2G concepts. The latter guide the players interaction. Finally, we specify six services that aims to allow PM2Gs development and deployment.

21.FP.C - Simulação de Agentes com Capacidade Auditiva em Situações de Emergência [open]
Carlos Cony (UNISINOS)
Claudio Jung  (UNISINOS)
Soraia Musse (UNISINOS)
Bryan Garber (UNISINOS)
Este artigo propõe um novo modelo de percepção auditiva para estimular o movimento de agentes virtuais em situações de emergência. No modelo proposto, uma fonte sonora (alarme) é colocada em algum local do ambiente virtual, e o decaimento da intensidade do sem em função da distância é calculado. Quando a onda sonora atinge o agente virtual, também são levadas em consideração as diferentes sensibilidades do ouvido humano por faixa de freqüência, assim como a perda natural de audição em função da faixa etária. Se o estímulo final no ouvido virtual for suficientemente forte, o agente reage, evacuando o ambiente conforme um modelo de simulação de multidões baseado em Física.

22.FP.C - Simulação Realista de Tecidos [open]
Leandro Monteiro (State University of Campinas)
Wu Shin-Ting (UNICAMP)
A crescente busca pelo realismo nos jogos tem levado à integração da simulação de tecidos para fazer os movimentos de vestuários, sobre um personagem animado, mais próximos da nossa percepção usual. Este artigo objetiva apresentar a eficácia de um paradigma geometricamente exato, fundamentado na teoria de superfície de Cosserat Elástica, para simulação de tecidos, descrevendo uma implementação com integração temporal explícita, de baixo custo computacional. Dessa forma, nossa implementação do modelo deformável resulta em comportamentos físicos convincentes, mesmo usando integrações temporais simples, como as integrações Euler ou Verlet.

23.FP.C - Uma Plataforma para Jogos Móveis Massivamente Multiusuário [open]
Andrea Menezes (Universidade Federal de Pernambuco)
Carlos Eduardo Silva (CIn/UFPE)
Daniel Arraes (CESAR)
Davi Pedrosa (CIn/UFPE)
Fernando Brayner (CESAR/Meantime)
Isabel Silveira (Universidade Federal de Pernambuco)
Marcus Machado (Universidade Federal de Pernambuco
Rafael Borges (CESAR/Meantime)
Geber Ramalho (Universidade Federal de Pernambuco)
Mobile Massively Multiplayer Online Games (3MOG) represent an important market trend in games industry, combining massive multiplayer with mobile games. Although some requirements for a 3MOG supporting platform have been enumerated in the literature, there is neither a reference implementation, nor an in-depth study of the criteria, guiding such an implementation. In this paper, we discuss the importance of the platforms in the development of 3MOGs and criteria to evaluate them. Finally, we present a case study that illustrates the implementation and evaluation of two different approaches to this kind of platform.

24.FP.C - Um Estudo de Caso Sobre a Construção e a Integração de Dispositivos Hápticos com Aplicações Interativas [open]
Thiago Farias (Universidade Federal de Pernambuco)
Daliton Silva (UFPE)
Guilherme Moura (UFPE)
João Marcelo Teixeira (Universidade Federal de Pernambuco)
Luiz Henrique Costa (GRVM-UFPE)
Guilherme Dias (GPRT)
Veronica Teichrieb (Universidade Federal de Pernambuco)
Judith Kelner (UFPE)
Este artigo apresenta o HapticCycle, um dispositivo de interação háptico construído e integrado com um jogo 3D que fornece retorno de força para o usuário. O HapticCycle é uma bicicleta adaptada que funciona como um joystick USB com vibração. O retorno háptico fornecido pela aplicação ocorre pela simulação de resistência de acordo com o relevo de um terreno, percebida no ato de pedalar a bicicleta. A integração do dispositivo com a aplicação foi implementada usando a plataforma de abstração CIDA, que permite a comunicação em tempo real entre dispositivo de controle e jogo. Comprovou-se através de uma avaliação que a interação com dispositivos hápticos aumenta o nível de imersão do usuário na aplicação. O HapticCycle, o jogo e sua integração, bem como a avaliação, são detalhadamente descritos.

25.FP.C - Usando Atores Sintéticos em Jogos Sérios: O Case SmartSim [open]
Danielle Rousy Silva (Universidade Federal de Pernambuco)
Geber Ramalho (Universidade Federal de Pernambuco)
Patrícia Tedesco (Centro de Informática – UFPE)
This paper describes the use of synthetic actors, a kind of intelligent agent with personality and emotions, as characters in serious games that learn soft skills. This kind of skill is more difficult to simulate and require great realism in relation to characters behavior. The synthetic actor when used in these games could improve the realism and characters intelligence, providing to the player a rich environment at experimentation and learning.

26.FP.C - Uso de Quadfields para Otimizar a Largura de Banda em Jogos Multi-Jogador [open]
Lauro Kozovits (PUC-Rio)
Claudio Esperanca (COPPE/Federal University of Rio de Janeiro)
Bruno Feijó (PUC-Rio)
Esteban Clua (PUC-Rio)
This paper uses the idea of Quadtrees in order to generate a space adaptative method for description of 3D data. This method is important for the reduction of data transmission for on-line applications, especially massive multiplayer games or mobile multi-player games based on SMS messages.