STARs

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https://diglib.eg.org/handle/10.2312/280

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    A Survey of Real-Time Hard Shadow Mapping Methods
    (The Eurographics Association, 2010) Scherzer, D.; Wimmer, M.; Purgathofer, W.; Helwig Hauser and Erik Reinhard
    Due to its versatility, speed and robustness, shadow mapping has always been a popular algorithm for fast hard shadow generation since its introduction in 1978, first for off-line film productions and later increasingly so in real-time graphics. So it is not surprising that recent years have seen an explosion in the number of shadow map related publications. The last survey that encompassed shadow mapping approaches, but was mainly focused on soft shadow generation, dates back to 2003 [HLHS03], while the last survey for general shadow generation dates back to 1990 [WPF90]. No survey that describes all the advances made in hard shadow map generation in recent years exists. On the other hand, shadow mapping is widely used in the game industry, in production, and in many other applications, and it is the basis of many soft shadow algorithms. Due to the abundance of articles on the topic, it has become very hard for practitioners and researchers to select a suitable shadow algorithm, and therefore many applications miss out on the latest high-quality shadow generation approaches. The goal of this survey is to rectify this situation by providing a detailed overview of this field. We provide a detailed analysis of shadow mapping errors and derive from this a comprehensive classification of the existing methods. We discuss the most influential algorithms, consider their benefits and shortcomings and thereby provide the reader with the means to choose the shadow algorithm best suited to his or her needs.
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    State of the Art in Procedural Noise Functions
    (The Eurographics Association, 2010) Lagae, A.; Lefebvre, S.; Cook, R.; DeRose, T.; Drettakis, G.; Ebert, D. S.; Lewis, J. P.; Perlin, K.; Zwicker, M.; Helwig Hauser and Erik Reinhard
    Procedural noise functions are widely used in Computer Graphics, from off-line rendering in movie production to interactive video games. The ability to add complex and intricate details at low memory and authoring cost is one of its main attractions. This state-of-the-art report is motivated by the inherent importance of noise in graphics, the widespread use of noise in industry, and the fact that many recent research developments justify the need for an up-to-date survey. Our goal is to provide both a valuable entry point into the field of procedural noise functions, as well as a comprehensive view of the field to the informed reader. In this report, we cover procedural noise functions in all their aspects. We outline recent advances in research on this topic, discussing and comparing recent and well established methods. We first formally define procedural noise functions based on stochastic processes and then classify and review existing procedural noise functions. We discuss how procedural noise functions are used for modeling and how they are applied on surfaces. We then introduce analysis tools and apply them to evaluate and compare the major approaches to noise generation. We finally identify several directions for future work.
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    On the Way Towards Topology-Based Visualization of Unsteady Flow
    (The Eurographics Association, 2010) Pobitzer, A.; Peikert, R.; Fuchs, R.; Schindler, B.; Kuhn, A.; Theisel, H.; Matkovic, K.; Hauser, H.; Helwig Hauser and Erik Reinhard
    Abstract Vector fields are a common concept for the representation of many different kinds of flow phenomena in science and engineering.Methods based on vector field topology have shown their convenience for visualizing and analyzing steady flow but a counterpart for unsteady flow is still missing. However, a lot of good and relevant work has been done aiming at such a solution. We give an overview of the research done on the way towards topology-based and -inspired visualization of unsteady flow, pointing out the different approaches and methodologies involved as well as their relation to each other, taking classical (i.e. steady) vector field topology as our starting point. Particularly, we focus on Lagrangian methods, space-time domain approaches, local methods, and stochastic and multi-field approaches. Furthermore, we illustrated our review with practical examples for the different approaches.
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    Visual Analysis of Large Graphs
    (The Eurographics Association, 2010) Landesberger, T. von; Kuijper, A.; Schreck, T.; Kohlhammer, J.; Wijk, J. J. van; Fekete, J.-D.; Fellner, Dieter W.; Helwig Hauser and Erik Reinhard
    The analysis of large graphs plays a prominent role in various fields of research and is relevant in many important application areas. Effective visual analysis of graphs requires appropriate visual presentations in combination with respective user interaction facilities and algorithmic graph analysis methods. How to design appropriate graph analysis systems depends on many factors, including the type of graph describing the data, the analytical task at hand, and the applicability of graph analysis methods. The most recent surveys of graph visualization and navigation techniques were presented by Herman et al. [HMM00] and Diaz [DPS02]. The first work surveyed the main techniques for visualization of hierarchies and graphs in general that had been introduced until 2000. The second work concentrated on graph layouts introduced until 2002. Recently, new techniques have been developed covering a broader range of graph types, such as time-varying graphs. Also, in accordance with ever growing amounts of graph-structured data becoming available, the inclusion of algorithmic graph analysis and interaction techniques becomes increasingly important. In this State-of-the-Art Report, we survey available techniques for the visual analysis of large graphs. Our review firstly considers graph visualization techniques according to the type of graphs supported. The visualization techniques form the basis for the presentation of interaction approaches suitable for visual graph exploration. As an important component of visual graph analysis, we discuss various graph algorithmic aspects useful for the different stages of the visual graph analysis process.
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    Editorial
    (The Eurographics Association, 2010) Hauser, Helwig; Reinhard, Erik; Helwig Hauser and Erik Reinhard
    The annual EUROGRAPHICS conference includes several very interesting tracks, of which the State-of-the-Art Reports (STARs) has proved to be consistently popular. The reports in this track survey topic areas that have not been covered before, at least not recently, and allow interested readers to quickly gain an overview as well as a first understanding of the related research in the covered areas.
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    A Survey on Shape Correspondence
    (The Eurographics Association, 2010) Kaick, O. van; Zhang, H.; Hamarneh, G.; Cohen-Or, D.; Helwig Hauser and Erik Reinhard
    We present a review of the correspondence problem and its solution methods, targeting the computer graphics audience. With this goal in mind, we focus on the correspondence of geometric shapes represented by point sets, contours or triangle meshes. This survey is motivated by recent developments in the field such as those requiring the correspondence of non-rigid or time-varying surfaces and a recent trend towards semantic shape analysis, of which shape correspondence is one of the central tasks. Establishing a meaningful shape correspondence is a difficult problem since it typically relies on an understanding of the structure of the shapes in question at both a local and global level, and sometimes also the shapes functionality. However, despite its inherent complexity, shape correspondence is a recurrent problem and an essential component in numerous geometry processing applications. In this report, we discuss the different forms of the correspondence problem and review the main solution methods, aided by several classification criteria which can be used by the reader to objectively compare the methods. We finalize the report by discussing open problems and future perspectives.
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    Image Statistics and their Applications in Computer Graphics
    (The Eurographics Association, 2010) Pouli, T.; Cunningham, D. W.; Reinhard, E.; Helwig Hauser and Erik Reinhard
    The statistics of natural images have attracted the attention of researchers in a variety of fields and have been used as a means to better understand the human visual system and its processes. A number of algorithms in computer graphics, vision and image processing take advantage of such statistical findings to create visually more plausible results. With this report we aim to review the state of the art in image statistics and discuss existing and potential applications within computer graphics and related areas.
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    Simplex and Diamond Hierarchies: Models and Applications
    (The Eurographics Association, 2010) Weiss, K.; Floriani, L. De; Helwig Hauser and Erik Reinhard
    Hierarchical spatial decompositions are a basic modeling tool in a variety of application domains. Several papers on this subject deal with hierarchical simplicial decompositions generated through simplex bisection. Such decompositions, originally developed for finite elements, are extensively used as the basis for multiresolution models of scalar fields, such as terrains, and static or time-varying volume data. They have also been used as an alternative to quadtrees and octrees as spatial access structures and in other applications. In this state of the art report, we distinguish between approaches that focus on a specific dimension and those that apply to all dimensions. The primary distinction among all such approaches is whether they treat the simplex or clusters of simplexes, called diamonds, as the modeling primitive. This leads to two classes of data structures and to different query approaches. We present the hierarchical models in a dimension independent manner, and organize the description of the various applications, primarily interactive terrain rendering and isosurface extraction, according to the dimension of the domain.