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Item Interactive Projective Texturing for Non-Photorealistic Shading of Technical 3D Models(The Eurographics Association, 2013) Lux, Roland; Trapp, Matthias; Semmo, Amir; Döllner, Jürgen; Silvester Czanner and Wen TangThis paper presents a novel interactive rendering technique for creating and editing shadings for man-made objects in technical 3D visualizations. In contrast to shading approaches that use intensities computed based on surface normals (e.g., Phong, Gooch, Toon shading), the presented approach uses one-dimensional gradient textures, which can be parametrized and interactively manipulated based on per-object bounding volume approximations. The fully hardware-accelerated rendering technique is based on projective texture mapping and customizable intensity transfer functions. A provided performance evaluation shows comparable results to traditional normal-based shading approaches. The work also introduce simple direct-manipulation metaphors that enables interactive user control of the gradient texture alignment and intensity transfer functions.Item The Dynamic Animation of Ambulatory Arthropods(The Eurographics Association, 2007) Cenydd, Llyr ap; Teahan, William; Ik Soo Lim and David DuceWhilst advances in real-time computer graphics continue to permit the development of increasingly vivid virtual worlds, the degree of interaction between the environment and the animated characters within remains relatively limited. There has been little research into the realistic real-time simulation of creatures with the ability to scale arbitrary surfaces and fully explore their environment. Natural looking animations of such feats would greatly enhance immersion in computer games, as well as being of benefit to fields such as phobia therapy and Artificial Life research. We present a system for dynamically animating ground based arthropods in real-time, capable of traversing realistically across a complex, arbitrary environment. The physical simulation of the virtual world further grounds the creatures, enabling complex emergent animations to form.Item Recreational Motion Simulation: A New Frontier for Virtual Worlds Research(The Eurographics Association, 2021) Williams, Benjamin; Headleand, Christopher J.; Xu, Kai and Turner, MartinMotion simulation is a developing field which continues to grow with the recent incline in commercial virtual reality. Whilst the majority of motion simulation research focuses on flight simulation and training, its utility in recreational settings is often overlooked. Despite this lack of research, the use of motion simulators for recreational purposes spans decades, and is still today one of the most popular applications of motion simulator devices. Furthermore, with the recent development of low-cost motion simulation platforms, consumers have begun to use these devices in the home. Research regarding motion simulation and its effects in recreational experiences is needed now more than ever, and in this position paper we outline several reasons for its importance.Item Real-Time Rendering of Molecular Dynamics Simulation Data: A Tutorial(The Eurographics Association, 2017) Alharbi, Naif; Chavent, Matthieu; Laramee, Robert S.; Tao Ruan Wan and Franck VidalAchieving real-time molecular dynamics rendering is a challenge, especially when the rendering requires intensive computation involving a large simulation data-set. The task becomes even more challenging when the size of the data is too large to fit into random access memory (RAM) and the final imagery depends on the input and output (I/O) performance. The large data size and the complex computation processing per frame pose a number of challenges. i.e. the I/O performance bottleneck, the computational processing performance costs, and the fast rendering challenge. Handling these challenges separately consumes a significant portion of the total processing time which may result in low frame rates. We address these challenges by proposing an approach utilizing advanced memory management and bridging the Open Computing Language (OpenCL) and Open Graphics Library (OpenGL) drivers to optimize the final rendering frame rate. We illustrate the concept of the memory mapping technique and the hybrid OpenCL and OpenGL combination through a real molecular dynamics simulation example. The simulation data-set specifies the evolution of 336,260 particles over 1981 time steps occupying 8 Gigabyte of memory. The dynamics of the system including the lipid-protein interactions can be rendered at up to 40 FPS.Item Discrete Element Modelling Using a Parallelised Physics Engine(The Eurographics Association, 2009) Longshaw, Stephen M.; Turner, Martin J.; Finch, Emma; Gawthorpe, Robert; Wen Tang and John CollomosseDiscrete Element Modelling (DEM) is a technique used widely throughout science and engineering. It offers a convenient method with which to numerically simulate a system prone to developing discontinuities within its structure. Often the technique gets overlooked as designing and implementing a model on a scale large enough to be worthwhile can be both time consuming and require specialist programming skills. Currently there are a few notable efforts to produce homogenised software to allow researchers to quickly design and run DEMs with in excess of 1 million elements. However, these applications, while open source, are still complex in nature and require significant input from their original publishers in order for them to include new features as a researcher needs them. Recently software libraries notably from the computer gaming and graphics industries, known as physics engines, have emerged. These are designed specifically to calculate the physical movement and interaction of a system of independent rigid bodies. They provide conceptual equivalents of real world constructions with which an approximation of a realistic scenario can be quickly built. This paper presents a method to utilise the most notable of these engines, NVIDIAs PhysX, to produce a parallelised geological DEM capable of supporting in excess of a million elements.Item Augmented Reality with Multilayer Occlusion(The Eurographics Association, 2006) Feng, Yan; Chen, Yimin; Louise M. Lever and Mary McDerbyAn algorithm for realizing multilayer occlusion in augmented reality (AR) is presented in this paper. We have designed a special scene graph tree comprised of some special nodes, namely EMO nodes. According to the location of real moving object, different EMO node will be activated in real-time, consequently realizing the multilayer occlusion. Differing qualitatively from previous work in AR occlusion, our algorithm realizes multilayer occlusion, and its application domain involves indoor-field occluded objects, which are several meters distant from the viewer. Previous related work has focused on monolayer occlusion, and near-field occluded objects, which are within or just beyond arm s reach. In addition, BP neural network is improved to correct the nonlinear error of magnetic sensor, consequently to detect occlusion more effectively. Experimental results are provided to demonstrate the multilayer indoor-field occlusion.Item Accurate and Marker-less Head Tracking Using Depth Sensors(The Eurographics Association, 2013) Breidt, Martin; Bülthoff, Heinrich H.; Curio, Cristóbal; Silvester Czanner and Wen TangParameterized, high-fidelity 3D surface models can not only be used for rendering animations in the context of Computer Graphics (CG), but have become increasingly popular for analyzing data, and thus making these accessible to CG systems in an Analysis-by-Synthesis loop. In this paper, we utilize this concept for accurate head tracking by fitting a statistical 3D model to marker-less face data acquired with a low-cost depth sensor, and demonstrate its robustness in a challenging car driving scenario. We compute 3D head position and orientation with a mesh-based 3D shape matching algorithm that is independent of person identity and sensor type, and at the same time robust to facial expressions, speech, partial occlusion and illumination changes. Different strategies for obtaining the 3D face model are evaluated, trading off computational complexity and accuracy. Ground truth data for head pose are obtained from simultaneous marker-based tracking. Average tracking errors are below 6mm for head position and below 2.5 for head orientation, demonstrating the system's potential to be used as part of a non-intrusive head tracking system for use in Augmented Reality or driver assistance systems.Item Towards Analytical Provenance Visualization for Criminal Intelligence Analysis(The Eurographics Association, 2016) Islam, Junayed; Anslow, Craig; Xu, Kai; Wong, William; Zhang, Leishi; Cagatay Turkay and Tao Ruan WanIn criminal intelligence analysis to complement the information entailed and to enhance transparency of the operations, it demands logs of the individual processing activities within an automated processing system. Management and tracing of such security sensitive analytical information flow originated from tightly coupled visualizations into visual analytic system for criminal intelligence that triggers huge amount of analytical information on a single click, involves design and development challenges. To lead to a believable story by using scientific methods, reasoning for getting explicit knowledge of series of events, sequences and time surrounding interrelationships with available relevant information by using human perception, cognition, reasoning with database operations and computational methods, an analytic visual judgmental support is obvious for criminal intelligence. Our research outlines the requirements and development challenges of such system as well as proposes a generic way of capturing different complex visual analytical states and processes known as analytic provenance. The proposed technique has been tested into a large heterogeneous event-driven visual analytic modular analyst’'s user interface (AUI) of the project VALCRI (Visual Analytics for Sensemaking in Criminal Intelligence) and evaluated by the police intelligence analysts through it's visual state capturing and retracing interfaces. We have conducted several prototype evaluation sessions with the groups of end-users (police intelligence analysts) and found very positive feedback. Our approach provides a generic support for visual judgmental process into a large complex event-driven AUI system for criminal intelligence analysis.Item Model and Visualise the Relationship between Energy Consumption and Temperature Distribution in Cold Rooms(The Eurographics Association, 2011) Ma, Ji; Murphy, D.; O'Mathuna, C.; Hayes, M.; Provan, G.; Ian Grimstead and Hamish CarrIn the area of food and pharmacy cold storage, temperature distribution is considered as a key factor. Inappropriate distribution of temperature during the cooling process in cold rooms will cause the deterioration of the quality of products and therefore shorten their life-span. In practice, in order to maintain the distribution of temperature at an appropriate level, large amount of electrical energy has to be consumed to cool down the volume of space, based on the reading of a single temperature sensor placed in every cold room. However, it is not clear and visible that what is the change of energy consumption and temperature distribution over time. It lacks of effective tools to visualise such a phenomenon. In this poster, we initially present a solution which combines a visualisation tool with a Computational Fluid Dynamics (CFD) model together to enable users to explore such phenomenon.Item Multimodal Visualization with Interactive Closeups(The Eurographics Association, 2009) Ropinski, Timo; Viola, Ivan; Biermann, Martin; Hauser, Helwig; Hinrichs, Klaus; Wen Tang and John CollomosseAbstract Closeups are used in illustrations to provide detailed views on regions of interest. They are integrated into the rendering of the whole structure in order to reveal their spatial context. In this paper we present the concept of interactive closeups for medical reporting. Each closeup is associated with a region of interest and may show a single modality or a desired combination of the available modalities using different visualization styles. Thus it becomes possible to visualize multiple modalities simultaneously and to support doctor-to-doctor communication on the basis of interactive multimodal closeup visualizations. We discuss how to compute a layout for 2D and 3D closeups, and how to edit a closeup configuration to prepare a presentation or a subsequent doctor-to-doctor communication. Furthermore, we introduce a GPU-based rendering algorithm, which allows to render multiple closeups at interactive frame rates. We demonstrate the application of the introduced concepts to multimodal PET/CT data sets additionally co-registered with MRI.