Enhancing the experience of 3D virtual worlds with a cartographic generalization approach

In this work we propose a new approach for fast visualization and exploration of virtual worlds based on the use of cartographic concepts and techniques. Versions of cartographic maps with different levels of details can be created by using a set of operations named cartographic generalization. Cartographic generalization employs twelve operators and domain-specific knowledge, being the contribution of this work their transposition to 3D virtual worlds. The architecture of a system for 3D generalization is proposed and the system is implemented. Differently from traditional cartographic processes, we use artificial intelligence for both selecting the key objects and applying the operators. As a case study, we present the simplification of the historical quarter of Recife (Brazil).     

Language and design in text-based virtual worlds

Design can be characterized using a linguistic model which compares the use and power of language in real-life with its use and power in text-based virtual worlds. In this paper, the theory of speech acts is used as a background and a point of development to analyse and model design in the virtual space. Metaphors and other linguistic constructs become fundamental in the realisation of an innovative theory that helps users to design in virtual worlds. Examples of how language can be used for design purposes and a parallel with linguistic theories support the author’s thesis that words can ‘do things’ in the electronic space.     

Modeling Methods for Reusable and Interoperable Virtual Entities in Multimedia Virtual Worlds

Virtual Worlds are facing several challenges to become a mature technology commonly used in their numerous potential applications such as games, training, education, health and collaborative work. Main challenges are the introduction of multimedia in virtual worlds and the decrease of the cost and the required time for their design, which remains an empirical process. This paper proposes a methodology for introducing multimedia and decreasing the cost and needed time. The main interest of the proposed methodology is to provide virtual worlds with multimedia, interoperability and reusability properties. Interoperability enables virtual entities belonging to virtual worlds independently designed (i.e., no prior explicit agreement exists between theirs respective designers) to interact with each others. Reusability enables virtual worlds designers to use a virtual entity pattern initially designed for a virtual world A to be used in the design of a new virtual world B. The originality of this methodology relies on multiagent concepts and learning techniques for avoiding prior complex specifications tasks to achieve interoperability and reusability of multimedia virtual entities in virtual worlds.     

A domain-oriented end-user design environment for generating interactive 3D virtual chemistry experiments

Three-dimensional virtual worlds are potentially feasible for building virtual educational environments. However, educators face technical challenges to apply these technologies because creating virtual educational environments based on virtual worlds demands 3D modeling and programming skills. This paper proposes a method to lower the technical barriers through domain-oriented interfaces with languages and environments that are familiar to educators. A domain-oriented end-user design environment, iVirtualWorld, is designed and developed to implement the proposed method in a specific educational domain, namely introductory chemistry experiments. This web-based environment provides end-users with domain-oriented building blocks, which can be assembled to create 3D virtual chemistry experiments. A usability evaluation and a comparative case study are designed to evaluate the system among chemistry educators, who are the target audience. The usability evaluation contains a task requiring participants to create a 3D virtual chemistry experiment and a voluntary semi-structured interview. The case study compares a virtual experiment generated using iVirtualWorld with an experiment in a commercial virtual chemistry laboratory system. The results show that 1) the domain-oriented end-user design environment enables participants to generate the 3D virtual chemistry experiment within 30 min; 2) participants gain confidence on creating 3D virtual experiments by themselves using iVirtualWorld; 3) participants confirm the usefulness of applying the system in introductory chemistry education; and 4) iVirtualWorld is considered more intuitive and straightforward for students to focus on finishing the experiment without being distracted than the commercial virtual chemistry laboratory system. Areas that can benefit from the system most and areas where the system is less effective are identified by participants. The responses also reveal the limitations of the current system and suggest directions for future improvement.     

AutoVisual: rule-based design of interactive multivariatevisualizations

An extension to the n-Vision visualization system, which provides users with a 3D virtual world within which they can visualize and manipulate representations of multivariate relations is discussed. The extension, AutoVisual, is rule based system that eliminates the difficulty in choosing among the many alternative when designing visualizations. AutoVisual designs interactive virtual worlds for visualizing and exploring multivariate relations. It is guided by user-specified visualization tasks and a rule base of design principles. AutoVisual's visualization techniques and the visualization tasks it handles are described. Example visualizations AutoVisual has generated for two problem domains are discussed     

皮鞋CAD中真实感效果表现及其关键技术

开发的鞋样CAD系统可直接在计算机上进行鞋样三维设计，生成真实感效果，设计师可以方便地修改设计，直至达到满意的设计效果，提出并实现了鞋样真实感设计的关键技术与方法，包括鞋楦三维模型的重构、鞋样的分片与展平、样片间缝合造型、纹理映射及基于控制图的凸凹纹理生成，将这些技术应用于自主开发的ShoePower鞋样CAD系统中，获得了满意的设计效果。     

一个基于Java3D的协同虚拟环境工作平台*

协同虚拟环境为多用户构造一个可以沉浸其中漫游的虚拟空间,并支持用户之间的协同活动。在军事模拟、远程教育、娱乐等领域有广泛的应用。Java3D是一种高层3D API,可用于快速构建虚拟现实系统。尝试用Java3D技术构造一个协同虚拟环境工作平台原型系统,重点介绍了开发中的技术问题, 讨论了场景建模、消息通信、人机交互、化身控制、白板管理和视频显示等主要功能,并给出了一些具有较高参考价值的代码。     

Transforming GIS data into functional road models for large-scale traffic simulation

There exists a vast amount of geographic information system (GIS) data that model road networks around the world as polylines with attributes. In this form, the data are insufficient for applications such as simulation and 3D visualization-tools which will grow in power and demand as sensor data become more pervasive and as governments try to optimize their existing physical infrastructure. In this paper, we propose an efficient method for enhancing a road map from a GIS database to create a geometrically and topologically consistent 3D model to be used in real-time traffic simulation, interactive visualization of virtual worlds, and autonomous vehicle navigation. The resulting representation provides important road features for traffic simulations, including ramps, highways, overpasses, legal merge zones, and intersections with arbitrary states, and it is independent of the simulation methodologies. We test the 3D models of road networks generated by our algorithm on real-time traffic simulation using both macroscopic and microscopic techniques.