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Now showing 1 - 9 of 9
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    Measuring Realism in Hair Rendering
    (The Eurographics Association, 2013) Ramesh, Girish; Turner, Martin J.; Silvester Czanner and Wen Tang
    Visualisation of hair is an extremely complex problem within the field of Computer Graphics. Over the last 10 years, huge strides have been made in the area of physically-based hair rendering, giving rise to many applications in various fields other than the graphics industry. Given the number of models for hair rendering, there is no well defined evaluation process to measure the realism in the hair models in use today. For this work-in-progress paper, we propose an evaluation process not only to evaluate the realism in hair rendering models, but also examine the various effects that contribute to its realistic perception. This builds an index of realism based on experiments with computer generated models, and then proposes comparing the results with values obtained from computational tomography, optical imaging and goniophotometer readings.
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    Projectional Radiography Simulator: an Interactive Teaching Tool
    (The Eurographics Association, 2019) Sujar, Aaron; Kelly, Graham; García, Marcos; Vidal, Franck; Vidal, Franck P. and Tam, Gary K. L. and Roberts, Jonathan C.
    Radiographers need to know a broad range of knowledge about X-ray radiography, which can be specific to each part of the body. Due to the harmfulness of the ionising radiation used, teaching and training using real patients is not ethical. Students have limited access to real X-ray rooms and anatomic phantoms during their studies. Books, and now web apps, containing a set of static pictures are then often used to illustrate clinical cases. In this study, we have built an Interactive X-ray Projectional Simulator using a deformation algorithm with a real-time X-ray image simulator. Users can load various anatomic models and the tool enables virtual model positioning in order to set a specific position and see the corresponding X-ray image. It allows teachers to simulate any particular X-ray projection in a lecturing environment without using real patients and avoiding any kind of radiation risk. This tool also allows the students to reproduce the important parameters of a real X-ray machine in a safe environment. We have performed a face and content validation in which our tool proves to be realistic (72% of the participants agreed that the simulations are visually realistic), useful (67%) and suitable (78%) for teaching X-ray radiography.
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    Virtual Reality: A Literature Review and Metrics-based Classification
    (The Eurographics Association, 2018) Ankomah, Peter; Vangorp, Peter; {Tam, Gary K. L. and Vidal, Franck
    This paper presents a multi-disciplinary overview of research evaluating virtual reality (VR). The main aim is to review and classify VR research based on several metrics: presence and immersion, navigation and interaction, knowledge improvement, performance and usability. With the continuous development and consumerisation of VR, several application domains have studied the impact of VR as an enhanced alternative environment for performing tasks. However, VR experiment results often cannot be generalised but require specific datasets and tasks suited to each domain. This review and classification of VR metrics presents an alternative metrics-based view of VR experiments and research.
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    Optimising Underwater Environments for Mobile VR
    (The Eurographics Association, 2019) Cenydd, Llyr ap; Headleand, Christopher; Vidal, Franck P. and Tam, Gary K. L. and Roberts, Jonathan C.
    Mobile Virtual Reality (VR) has advanced considerably in the last few years, driven by advances in smartphone technology. There are now a number of commercial offerings available, from smartphone powered headsets to standalone units with full positional tracking. Similarly best practices in VR have matured quickly, facilitating comfortable and immersive VR experiences. There remains however many optimisation challenges when working with these devices, as while the need to render at high frame rates is universal, the hardware is limited by both computational power and battery capacity. There is also often a requirement that apps run smoothly across a wide variety of headsets. In this paper, we describe lessons learned in rendering and optimising underwater environments for mobile VR, based on our experience developing the popular aquatic safari application 'Ocean Rift'. We start by analyzing essential best practices for mobile app development, before describing low-cost techniques for creating immersive underwater environments. While some techniques discussed are universal to modern mobile VR development, we also consider issues that are unique to underwater applications.
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    Controlling 3D Visualisations with Multiple Degrees of Freedom
    (The Eurographics Association, 2019) Sandoval, Mario; Morris, Tim; Turner, Martin; Vidal, Franck P. and Tam, Gary K. L. and Roberts, Jonathan C.
    In this paper, the two major components of a new multi-layer framework ideal for two-handed interaction in desktop virtual environments called Library for Interactive Settings of User-Mode (LISU) are explained. In addition, we evaluate LISU performance with a group of participants and we report some of our initial results by giving an analysis of user experiences, and interaction speed.
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    A Cost Effective, Accurate Virtual Camera System for Games, Media Production and Interactive Visualisation Using Game Motion Controllers
    (The Eurographics Association, 2013) Bett, Matthew; Michno, Erin; McAlpine, Keneth B.; Silvester Czanner and Wen Tang
    Virtual cameras and virtual production techniques are an indispensable tool in blockbuster filmmaking but due to their integration into commercial motion-capture solutions, they are currently out-of-reach to low-budget and amateur users. We examine the potential of a low budget high-accuracy solution to create a simple motion capture system using controller hardware designed for video games. With this as a basis, a functional virtual camera system was developed which has proven usable and robust for commercial testing.
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    Virtual Reality Callouts - Demonstrating Knowledge With Spatial-Related Textual Information
    (The Eurographics Association, 2019) Horst, Robin; Degreif, Anika; Mathy, Marvin; Dörner, Ralf; Vidal, Franck P. and Tam, Gary K. L. and Roberts, Jonathan C.
    Virtual (VR) and augmented reality (AR) can bring an added value during the demonstration of knowledge, as for example within an interactive research demo. Callouts are strings of text which are connected by a line to a specific feature of an object. These visual annotations can be used during such demos and can be placed in different kinds of media, such as illustrations, technical drawings, images and videos. Callouts are also used in virtual 3D environments to anchor textual information to a specific point in space. Therefore they can be a valuable tool for virtually demonstrating knowledge. The alignment of callouts in such information rich environments is an elemental factor within the view management of the VR scene. In this paper we propose a concept for interactive microlearning application for knowledge demonstration that uses callouts as a fundamental element. We distinguish three types of interactive callout-representations by their alignment relative to the user, for being static or dynamic in their position and orientation. Within an implementation of the different callout versions we show the feasibility and in a user study we indicate a user-preference towards static positioned callouts.
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    Comparing Gestural Interfaces using Kinect and OpenPose
    (The Eurographics Association, 2019) Rahman, Aminur; Clift, Louis G.; Clark, Adrian F.; Vidal, Franck P. and Tam, Gary K. L. and Roberts, Jonathan C.
    We describe the implementation of a gesture recognition facility for navigating through virtual reality applications in a shared VR facility. An implementation based around the Microsoft Kinect is described and the fruits of several years' experience are summarized. An alternative implementation based around the OpenPose library is then presented and the two are compared.
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    A Somatic Approach to Combating Cybersickness Utilising Airflow Feedback
    (The Eurographics Association, 2019) Harrington, Jake; Williams, Benjamin; Headleand, Christopher; Vidal, Franck P. and Tam, Gary K. L. and Roberts, Jonathan C.
    Abstract This paper presents a novel somatosensory approach towards reducing the risk of cybersickness during virtual reality locomotion in a 3D environment. We start by presenting theories regarding the cause of cybersickness which led to the proposal and construction of a prototype airflow-based feedback system. The solution proposed by this paper builds on the concept of sensory misalignment, where the body struggles understand its state due to conflicting sensory feedback and consequently generates negative health symptoms and discomfort. To evaluate the work an experiment was carried out where 40 participants drive a simulated car around a virtual environment. In one condition the participants had additional somatosensory feedback regarding their motion, provided by a fan synchronised to their speed in the virtual world. In the second condition there was no additional feedback. We evaluated both conditions for cybersickness and presence, and showed a statistically significant improvement for both in the condition using airflow feedback. We conclude with a discussion of the results, and present a direction for possible future research.