A declarative approach to procedural modeling of virtual worlds

Procedural modelling is an attractive alternative to cut down the costs of manual content creation for virtual worlds. We discuss our declarative modelling approach to the creation of 3D virtual worlds, which integrates a variety of procedural techniques in order to enable a non-specialist user to interactively create a complete 3D virtual world in minutes. In particular, we introduce procedural sketching, a novel paradigm which allows designers to quickly specify and see the effects of their procedural modelling operations, and describe its main features as implemented in our prototype system SketchaWorld. Two main interaction modes are described, for specifying the landscape and terrain features, respectively. Our approach automatically fits all generated terrain features with their surroundings, for example by smoothing out rough terrain for roads, or creating a bridge to cross a river. It is concluded that this approach provides designers with the productivity gain of procedural methods, while still allowing for fine user control and actively supporting iterative modelling.

The paper is proposing a framework of a dynamic social evolution model called SynopCity - Virtual City serving as virtual living laboratory for a research of topics related to smart cities. Concept of SynopCity - Virtual City is an application representing a model of virtual city, connected to a social network (www.synopcity.com) where network's members are acting as a citizens developing new urban developments in a virtual world under specific rules and regulations. It will allow authors of paper to study complex social behavior of all parties responsible for city development and decision making processes based on available historical data collected during this experiment of dynamic social evolution model development. Citizens are actively participating on this process along with model authorities and community representatives following statutes, rules and law. Authors of paper are also proposing an implementation of Industry 4.0 principles. The city is acting as an Industry 4.0 factory where all processes and relation between product and production are mirrored between physical factory networked systems and factory's virtual model.

Virtual 3D city models are essential visualization tools for effective communication of complex urban spatial information. Immersive visualization of virtual 3D city models offers an intuitive access to and an effective way of realization of urban spatial information, enabling new collaborative applications and decision-support systems. This paper discusses techniques for and usage of fully immersive environments for visualizing virtual 3D city models by advanced 3D rendering techniques. Fully immersive environments imply a number of specific requirements for both hardware and software, which are discussed in detail. Further, we identify and outline conceptual and technical challenges as well as possible solution approaches by visualization system prototypes for large-scale, fully immersive environments. We evaluate the presented concepts using two application examples and discuss the results.

Mixed reality is different from the virtual reality in that users can feel immersed in a space which is composed of not only virtual but also real objects. Thus, it is essential to realize seamless integration and interaction of the virtual and real worlds. We need depth information of the real scene to synthesize the real and virtual objects. We propose a two-stage algorithm to find smooth and precise disparity vector fields with sharp object boundaries in a stereo image pair for depth estimation. Hierarchical region-dividing disparity estimation increases the efficiency and the reliability of the estimation process, and a shape-adaptive window provides high reliability of the fields around the object boundary region. At the second stage, the vector fields are regularized with a energy model which produces smooth fields while preserving their discontinuities resulting from the object boundaries. The vector fields are used to reconstruct 3D surface of the real scene. Simulation results show that the proposed algorithm provides accurate and spatially correlated disparity vector fields in various kinds of images, and synthesized 3D models produce natural space where the virtual objects interact with the real world as if they are in the same world.

Article Virtual world modeler Share on Authors: Elton K. H. Tsang Department of Computer Science and Engineering, The Chinese University of Hong Kong, Hong Kong Department of Computer Science and Engineering, The Chinese University of Hong Kong, Hong KongView Profile , Hanqiu Sun Department of Computer Science and Engineering, The Chinese University of Hong Kong, Hong Kong Department of Computer Science and Engineering, The Chinese University of Hong Kong, Hong KongView Profile , Mark Green Department of Computer Science, University of Alberta, Canada Department of Computer Science, University of Alberta, CanadaView Profile Authors Info & Claims VRST '98: Proceedings of the ACM symposium on Virtual reality software and technologyNovember 1998 Pages 179–186https://doi.org/10.1145/293701.293734Online:02 November 1998Publication History 3citation432DownloadsMetricsTotal Citations3Total Downloads432Last 12 Months4Last 6 weeks0 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my AlertsNew Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteGet Access

Objective: Technology has changed our world; changed the way we communicate, the way we do business and the way education is delivered. As a result, undergraduate student cohorts come to university equipped with new technology, and educators need to transform the delivery of the curricula to satisfy a variety of learning styles. Nursing education, in particular, is developing and transforming to incorporate technology into the learning environment. Clinical placement opportunities are often sparse and alternative experiences need to be considered. Across nursing curricula, it has been recognised that technology has the capacity to provide real-life learning experiences that promote student engagement and meet the learning needs of a diverse student cohort. Methods: This paper will discuss the development of a “Virtual World” in an undergraduate nursing program in Western Australia. The Virtual World initiative is designed to support students to understand the holistic, health-centred intent of the curriculum. Results: Initial results have shown that the Virtual World and humanising the curriculum, has increased learner engagement, improved critical thinking and decision-making. It has enhanced and maintained a high level of student satisfaction and self efficacy as well as assisting the development of graduate nurses who perceive themselves as health advocates, problem-solvers and organisers of care. Research will continue to follow the use of the Virtual World model, incorporating a virtual family and its integration into the undergraduate nursing curriculum. Conclusions: In the current climate of nurse education and due to a reduction in availability of clinical placements, alternative authentic experiences need to be offered. The development of the Virtual World has enabled meaningful participation in a safe and supportive learning environment.

Despite steady research advances in many aspects of virtual reality, building and testing virtual worlds remains to be a very difficult process. Most virtual environments are still implemented using traditional programming language tools like compilers and debuggers. What makes virtual environment construction more difficult is that, on top of having to tackle with the traditional computational and logical errors, it is also an exploration task. Developers must find the right combination of various types of constituents of the virtual environment like the objects, display and simulation details, interaction and modalities, etc. Unlike ordinary programming tasks, for VR, the execution and development environments are different, not just in the temporal sense, but also in the physical sense. We propose that an interactive kernel approach can partly solve this problem and promote higher efficiency in VR content development. Developers can try out and explore different configurations of the constituents of the virtual environment and immediately see their impact (within the virtual world in construction) and optimize the content along the dimensions of performance, interaction usability, realism, and presence. The interactive kernel is part of PiVOT-2 (POSTECH Virtual reality system development Tool 2), a collection of tools that support a VR system development methodology called the CLEVR (Concurrent and LEvel by Level Development of VR System), previously proposed by the authors [Seo and Kim 2002]. CLEVR/PiVOT-2 is based on a flexible virtual object model called (PiVOT Object Model), that clearly segregates the aspects of form, function and behavior and the interactive kernel allows the developers to dynamically configure the respective attributes within the virtual world in construction. In this paper, we describe the details of how POM was designed, and demonstrate the effectiveness of using the interactive kernel in constructing virtual worlds.

The paper presents the development of an experimental Web-based design environment called Townscaping to be used at the conceptual stage of architectural and urban design. Inspired by Gordon Cullen’s seminal work on Townscape (1960’s–1970’s), the idea of Townscaping is to explore how 3D digital sketch design tools could be developed to operate in connection with a dynamic virtual city system under a user’s direct control. A prototype of Townscaping has been designed and implemented on the basis of an existing dynamic virtual city system. In Townscaping, a set of tools is provided for users to create and edit 3D graphic elements to be positioned directly onto the user-specified virtual city models. One of the key features of Townscaping is to enable sketching while navigation: designers can perform sketch design and gain immediate visual feedback while navigating the 3D virtual city models to any viewpoint at any moment. The current study suggests that it is feasible for virtual city models to serve as interactive urban contexts for 3D sketch design. Townscaping is considered primarily a research platform with which we are interested in investigating if designers’ engaging in 3D space conceptions may be enhanced through interacting and sketching with virtual townscapes.

Proceedings of the 2011 joint ACM workshop on Human gesture and behavior understanding

Extended-Reality Technologies: An Overview of Emerging Applications in Medical Education and Clinical Care.

With the relatively recent awareness of the fragility of the natural world environment (Rio Conference Earth Summit in 1992), Information Systems (IS) trying to identify and help to manage biodiversity have proliferated. Given the various data that they contain, they are complex applications, hardly accessible to the general public. At the same time, new communication systems allow a more natural assimilation of information: three-dimensional representations of immersive virtual worlds, also known as metaverses. By putting users in a reality reproduction built from IS, all information can be represented in a consistent virtual environment. But turning IS's data in a coherent metaverse is not a trivial process. Depending the IS's structure and the availability of metadata, several virtual worlds, representing several level of details, can be generated. This paper is a contribution to the analysis of the different possibilities to generate metaverses representing the information stored in the IS dedicated to biodiversity. It presents the generic process of worlds generation, the requirements, the different models of metaverses' structure, and the metadata that could be used to refine the level of detail.

VRML —the Virtual Reality Modeling Language— has estab-lished as the standard description language for 3D worlds on theInternet. Although it recently has been extended by features inorder to support behaviors and user interactions, enablingauthors to realize interactive virtual worlds, there is still a lack ofsupport to share such worlds with other users.In this paper we will present our approach on supportinglarge-scaled shared virtual worlds based on VRML by an appro-priate network infrastructure as well as mechanisms to partitionthese worlds. We will show how virtual worlds can be populatedby world-wide distributed users and applications, and the re-quirements to share behaviors and interactions between those.CR Categories and Subject Descriptors: C.2.2 [ComputerCommunication Networks]: Network Protocols; C.2.4 [Com-puter Communication Networks]: Distributed Systems -Dis-tributed applications; H.5.1 [Information Interfaces and Pre-sentation] Multimedia Information Systems - ArtificialRealities; I.3.2 [Computer Graphics]: Graphics Systems -Dis-tributed/network graphics;I.3.6 [Computer Graphics]: Meth-odology and Techniques - Interaction Techniques; I.3.7. [Com-puter Graphics]: Three-Dimensional Graphics and Realism -Virtual Reality;Additional Keywords Virtual reality modeling language(VRML), multiuser environments, subdivision of shared virtualworlds, multicasting.

Radar sensors are widely used in intelligent transportation systems. The performance of radar sensors in practical setups depends on many factors, such as sensor specifications, choice of locations, height and orientations of sensor installation. Currently, most of these choices are made by a rule of thumb. In many cases, trial and error changes of settings are required and several rounds of on-site measurements and adjustments are incurred, which are both inefficient and costly. To overcome these problems, this paper reports a 3D virtual radar system that can accurately predict and evaluate the performance of actual radar sensors using a standard computer. The proposed system builds upon a 3D virtual model of real world. It allows users to freely enter specifications for radar sensors and the underlying algorithm can efficient calculate and represent graphically in the 3D model by the coverage area of the chose radar sensors at the specified location in the virtual world. Comparison with experimental data obtained using hardware testbeds shows the result obtained by the virtual radar system is accurate.

3D reconstruction technology is the basis for the use of virtual reality technology to achieve a complete simulation of the virtual reality world. Therefore, 3D reconstruction technology has always been regarded as the main goal of research in emerging technology fields such as virtual reality. The advanced virtual reality technology is widely used in the correction treatment simulation process, and the correction treatment plan can be designed through intuitive diagnosis and analysis, so that patients and physicians to have an intuitive understanding of the corrective effects they have achieved before the formal start of treatment, which has considerable practical value. This article mainly focuses on the application of 3D modeling in assisted orthodontics. It has a simple understanding of the methods of oral modeling based on relevant data, and then summarizes the specific application of 3D reconstruction technology in orthodontics. In order to further understand the application of 3D technology in dentistry, this article carried out 3D modeling of the oral cavity. Through the modeling of the oral cavity, the difficulties in the application of 3D technology were discovered. Finally, the problems in the modeling process were monitored by experiments, and the experimental results obtained, the first group the average relative measurement accuracy of patients is 1.713%, the second group of patients is 1.690%, and the average relative measurement accuracy corresponding to the previous section is 4.430% and 4.114% (the relative value of the measurement is lower), the accuracy value (means the higher the accuracy).

The paper discusses the well-known concepts of matter, objects, environments, information and information field in relation to the proposed information representation of the interaction of objects and environments based on the description of their information structures. An overview of the methods of forming information structures for modeling objects, environments and processes is given. It is shown that without using the concept of the environment, as an entity in which objects exist and are reflected in time and in a certain space, it is not always possible to accurately describe the change in the state of an object. This is due to the fact that the current state of an object depends both on the action of other objects on it and on its ability to reflect a specific physical or other environment in which it and other objects exist. From the presented review of approaches to object-oriented methods of modeling objects, environments and processes, it can be concluded that it is fundamentally important to take into account the physical and spatial environment in which they interact in object methods of modeling and programming complex objects and systems. Using programming languages, we can create and even manage the information structures of objects and environments. They are called abstract because they are not informational representations of the corresponding physical objects and environments. An example of such capabilities are special programming languages ​​for creating virtual objects and virtual worlds. Created on the basis of special programming languages, virtual simulators help specialists of various professions acquire skills in managing real objects, technological processes, etc.