Platform Independent Real-Time X3D Shaders and their Applications in Bioinformatics Visualization

Since the introduction of programmable Graphics Processing Units (GPUs) and procedural shaders, hardware vendors have each developed their own individual real-time shading language standard. None of these shading languages is fully platform independent. Although this real-time programmable shader technology could be developed into 3D application on a single system, this platform dependent limitation keeps the shader technology away from 3D Internet applications. The primary purpose of this dissertation is to design a framework for translating different shader formats to platform independent shaders and embed them into the eXtensible 3D (X3D) scene for 3D web applications. This framework includes a back-end core shader converter, which translates shaders among different shading languages with a middle XML layer. Also included is a shader library containing a basic set of shaders that developers can load and add shaders to. This framework will then be applied to some applications in Biomolecular Visualization

The Petri Net Model for the Collaborative Virtual Environment on the Web

[[abstract]]This paper presents a Petri Net model to analyze the workflow of a web-based multiple participants virtual environment. The presented approach not only can conspicuously help the developer to comprehend the interaction relationship between the client-server virtual environments but also to easily construct a shared virtual world. Based on the presented Petri Net model, we propose an architecture for the collaborative virtual environment and implement a multiple user 3D web browsing system, called the SharedWeb system. Problems of providing the multi-user interaction on the Web and the solutions proposed by the Petri Net model are fully elaborated here. Some experimental results along with two demonstrated virtual world are also presented.[[notice]]補正完

Visualization of the modeled degradation of building flooring systems in building maintenance

The development of a maintenance programme for construction projects is a highly complex and data intensive undertaking. This exercise is characterised by the lack of relevant data on the one hand and the overwhelming amount of extraneous data on the other. The uncertainties and complexities have resulted in increased conservatism in the development of lifecycle evaluation of building maintenance programing, subsequently, these programmes tend to display the symptoms of either the maintenance actions being uneconomical or fall short of providing the appropriate service to the users of the building. The current research project is based on the premise that the visual approach will facilitate a just-in-time solution to maintenance scheduling, hence, the use of virtual simulation of the building is proposed. The broader aim of this research is to develop a complete building maintenance programme through visualisation of buildings as they degrade over time. Here, the focus is on the flooring system and the manner they degrade over time. This requires a better understanding of their pattern and rate of usage. To this end, Anthroposophy and Anthropocentric descriptions of human movement pattern have been used to describe the behaviour of 'subjects' and subsequently represent the pattern and density of the degradation of flooring systems. The mathematics representing this behaviour has been developed which enables it to be embedded into the proposed overall visual building maintenance model

Design discussion space : creating 3-D discussion environment over the Internet

Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998.Includes bibliographical references (p. 35-36).by Danai Kuangparichat.S.B.and M.Eng

Investigation and development of an advanced virtual coordinate measuring machine

This thesis was submitted for the degree of Doctor of Philosophy and was awarded by Brunel UniversityDimensional measurement plays a critical role in product development and quality control. With the continuously increasing demand for tighter tolerances and more complex workpiece shapes in the industry, dimensional metrology often becomes the bottleneck of taking the quality and performance of manufacturing to the next level. As one kind of the most useful and powerful measuring instruments, coordinate measuring machines (CMMs) are widely employed in manufacturing industries. Since the accuracy and efficiency of a CMM have a vital impact on the product quality, productivity and manufacturing cost, the evaluation and improvement of CMM performance have always been important research topics since the invention of CMM. A novel Advanced Virtual Coordinate Measuring Machine (AVCMM) is proposed against such a background. The proposed AVCMM is a software package that provides an integrated virtual environment, in which user can plan inspection strategy for a given task, carry out virtual measurement, and evaluate the uncertainty associated with the measurement result, all without the need of using a physical machine. The obtained estimate of uncertainty can serve as a rapid feedback for user to optimize the inspection plan in the AVCMM before actual measurement, or as an evaluation of the result of a performed measurement. Without involving a physical CMM in the inspection planning or evaluation of uncertainty, the AVCMM can greatly reduce the time and cost needed for such processes. Furthermore, as the package offers vivid 3D visual representation of the virtual environment and supports operations similar to a physical CMM, it does not only allow the user to easily plan and optimise the inspection strategy, but also provide a cost-effective, risk-free solution for training CMM operators. A modular, multitier architecture has been adopted to develop the AVCMM system, which incorporates a number of functional components covering CMM and workpiece modelling, error simulation, inspection simulation, feature calculation, uncertainty evaluation and 3D representation. A new engine for detecting collision/contact has been developed and utilized, which is suitable for the virtual environment of simulated CMM inspections. A novel approach has been established to calculate errors required for the error simulation, where the data are obtained from FEA simulations in addition to conventional experimental method. Monte Carlo method has been adopted for uncertainty evaluation and has been implemented with multiple options available to meet different requirements. A prototype of the proposed AVCMM system has been developed in this research. Its validity, usability and performance have been verified and evaluated through a set of experiments. The principles for utilising the AVCMM in practical use have also been established and demonstrated. The results have indicated that the proposed AVCMM system has great potentials to improve the functionalities and overall performance of CMMs.ORSAS and the School of Engineering and Design of Brunel University

Pathfinding in VRML

Virtual Reality Modelling Language (VRML) is a scene description language which describes three dimensional (3D) space to a computer. Thus the three axis of space that is inherent in our dimension X Y and Z is represented inside a computer. To many people VRML represents a new beginning for the World Wide Web (WWW) because it behaves more like the real world. VRML is experimental, interactive, continuous and of course, three dimensional. Algorithms in computing have been designed for 2D problem solving and this does not necessarily translate to problem solving on a 3D level. The aim of this project was to experiment with one of these algorithms within the domain of 3D space (VRML). This project chose to use an algorithm based on solving shortest path problems and then translate this algorithm for it to work in a 3D environment. Java, a programming language, was used to find the shortest path. The shortest path was then shown via the use of an animated camera going through the 3D environment in effect delivering a pathfinding system. VRML was used as the basis to create the 3D environment, thus the project creates a pathfinding system that can be used as a navigational tool within a VRML world

Motor de eventos

Dissertação de mestrado em Computação Gráfica e Ambientes Virtuais (área de especialização em Informática)“A Universidade do Minho, em particular o grupo de Gráficos, Interacção e Visão (GIV), em parceria com o Município de Ponte de Lima, desenvolveu um trabalho no âmbito do projecto ‘Ponte de Lima, Terra Rica da Humanidade’, que consistiu na modelação 3D, e apresentação sobre diversos formatos, da vila de Ponte de Lima na sua versão actual no início do século XXI, e numa possível reconstrução virtual da muralha construída no século XIV. De um ponto de vista académico e no âmbito da computação gráfica, este projecto permitiu ao grupo GIV atingir dois objectivos: a construção de um cenário virtual de grandes dimensões e um motor de renderização 3D completo e extremamente versátil.” [pl3D] A transcrição anterior refere-se ao motor gráfico de renderização 3D denominado Curitiba. Este permite visualizar modelos 3D, com capacidade para realizar múltiplos passos, possibilitando a geração de efeitos visuais complexos. Embora a demonstração do motor, no âmbito do projecto Ponte de Lima 3D, permitisse algumas animações e interactividade, estas foram de facto criadas através da alteração do próprio código, sem que houvesse na altura muito cuidado na elaboração de uma arquitectura para criar cenas dinâmicas. A interacção com alguns elementos no modelo, como por exemplo, clicando na marca que indica a subida do rio numa das grandes cheias ocorridas, provoca uma animação. Essa animação foi realizada de forma muito direccionada para o efeito desejado nesse momento, não permitindo generalizar de forma sistemática a criação de outras situações com animações diferentes, ou, mantendo animação, aplicá-la a outros modelos. Apesar de ter acoplado um motor de física e estar dotado de capacidades para facilmente ser expansível, o Curitiba permitia apenas criar um ambiente 3D estático sem interacção, a menos da movimentação da câmara no modo de primeira pessoa. Neste contexto pretende-se dotar o Curitiba da capacidade para definir e visualizar cenas dinâmicas, e com interacção, quer com o utilizador quer entre elementos da cena. É nesta perspectiva, a de acrescentar funcionalidade e interacção ao ambiente, que é proposto realizar nesta dissertação de mestrado, um estudo e implementação de uma arquitectura de software para um motor de eventos. Um motor de eventos que permita acrescentar diferentes tipos de interacção num ambiente 3D, que seja fácil de usar, genérico, e expansível, seguindo a própria filosofia do Curitiba.“Minho University, in particular the Graphics, Interaction and Vision team (GIV), in association with the council of Ponte de Lima has developed a project called ‘Ponte de Lima, a Land Rich in Humanity’, that consisted of the 3D modeling and presentation, in various formats, of the town of Ponte de Lima in its present version of the beginning of the XXIst century and in a virtual prospective reconstruction with the wall built in the XIVth century. From an academic point of view, and in the graphic computation field, this project allowed the GIV team to achieve two purposes: the construction of a large virtual scenario and a complete 3D rendering engine that is extremely versatile.” [pl3D] The previous quotation refers to a 3D rendering graphic engine called Curitiba. This allows 3D model visualization with multiple steps which make complex visual effects possible. Although the engine demonstration in the “Ponte de Lima 3D” project allowed some animation and interactivity, in fact they were achieved with the change of the engine’s own code, without taking into consideration at the time, the building of a dynamic architecture to create dynamic scenes. The interaction of some elements in the model, for instance, by clicking on a mark which represents the flooding of the river, causes an animation. That animation was achieved based on the wanted effect at the time, but it can’t be applied systematically when creating other situations with different animations or, when using that very animation on other models. Despite having engaged a physics engine and being able to be easily expandable, Curitiba, at the present moment, creates a static 3D ambience without interaction, besides the movement of the camera in first person mode. The aim of this work is to provide Curitiba with the ability to define and visualize dynamic scenes and with interaction among both the user and elements of the scene. To accomplish this goal, to add functionality and interaction to 3D environment, we propose to accomplish in this master work a software architecture study and implementation for an event engine. An event engine that permits expansion of different interaction types in 3D environment that is easy to use, generic and expandable, following the very philosophy of Curitiba

Web-based electromagnetic simulation

Master'sMASTER OF ENGINEERIN

3D Spatial Data Infrastructures for web-based Visualization

In this thesis, concepts for developing Spatial Data Infrastructures with an emphasis on visualizing 3D landscape and city models in distributed environments are discussed. Spatial Data Infrastructures are important for public authorities in order to perform tasks on a daily basis, and serve as research topic in geo-informatics. Joint initiatives at national and international level exist for harmonizing procedures and technologies. Interoperability is an important aspect in this context - as enabling technology for sharing, distributing, and connecting geospatial data and services. The Open Geospatial Consortium is the main driver for developing international standards in this sector and includes government agencies, universities and private companies in a consensus process. 3D city models are becoming increasingly popular not only in desktop Virtual Reality applications but also for being used in professional purposes by public authorities. Spatial Data Infrastructures focus so far on the storage and exchange of 3D building and elevation data. For efficient streaming and visualization of spatial 3D data in distributed network environments such as the internet, concepts from the area of real time 3D Computer Graphics must be applied and combined with Geographic Information Systems (GIS). For example, scene graph data structures are commonly used for creating complex and dynamic 3D environments for computer games and Virtual Reality applications, but have not been introduced in GIS so far. In this thesis, several aspects of how to create interoperable and service-based environments for 3D spatial data are addressed. These aspects are covered by publications in journals and conference proceedings. The introductory chapter provides a logic succession from geometrical operations for processing raw data, to data integration patterns, to system designs of single components, to service interface descriptions and workflows, and finally to an architecture of a complete distributed service network. Digital Elevation Models are very important in 3D geo-visualization systems. Data structures, methods and processes are described for making them available in service based infrastructures. A specific mesh reduction method is used for generating lower levels of detail from very large point data sets. An integration technique is presented that allows the combination with 2D GIS data such as roads and land use areas. This approach allows using another optimization technique that greatly improves the usability for immersive 3D applications such as pedestrian navigation: flattening road and water surfaces. It is a geometric operation, which uses data structures and algorithms found in numerical simulation software implementing Finite Element Methods. 3D Routing is presented as a typical application scenario for detailed 3D city models. Specific problems such as bridges, overpasses and multilevel networks are addressed and possible solutions described. The integration of routing capabilities in service infrastructures can be accomplished with standards of the Open Geospatial Consortium. An additional service is described for creating 3D networks and for generating 3D routes on the fly. Visualization of indoor routes requires different representation techniques. As server interface for providing access to all 3D data, the Web 3D Service has been used and further developed. Integrating and handling scene graph data is described in order to create rich virtual environments. Coordinate transformations of scene graphs are described in detail, which is an important aspect for ensuring interoperability between systems using different spatial reference systems. The Web 3D Service plays a central part in nearly all experiments that have been carried out. It does not only provide the means for interactive web-visualizations, but also for performing further analyses, accessing detailed feature information, and for automatic content discovery. OpenStreetMap and other worldwide available datasets are used for developing a complete architecture demonstrating the scalability of 3D Spatial Data Infrastructures. Its suitability for creating 3D city models is analyzed, according to requirements set by international standards. A full virtual globe system has been developed based on OpenStreetMap including data processing, database storage, web streaming and a visualization client. Results are discussed and compared to similar approaches within geo-informatics research, clarifying in which application scenarios and under which requirements the approaches in this thesis can be applied