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The state of the art in flow visualization: Dense and texture-based techniques
- Computer Graphics Forum
, 2004
"... Flow visualization has been a very attractive component of scientific visualization research for a long time. Usually very large multivariate datasets require processing. These datasets often consist of a large number of sample locations and several time steps. The steadily increasing performance of ..."
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Cited by 97 (29 self)
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Flow visualization has been a very attractive component of scientific visualization research for a long time. Usually very large multivariate datasets require processing. These datasets often consist of a large number of sample locations and several time steps. The steadily increasing performance of computers has recently become a driving factor for a reemergence in flow visualization research, especially in texture-based techniques. In this paper, dense, texture-based flow visualization techniques are discussed. This class of techniques attempts to provide a complete, dense representation of the flow field with high spatio-temporal coherency. An attempt of categorizing closely related solutions is incorporated and presented. Fundamentals are shortly addressed as well as advantages and disadvantages of the methods. Categories and Subject Descriptors (according to ACM CCS): I.3 [Computer Graphics]: visualization, flow visualization, computational flow visualization
Strategies for Direct Volume Rendering of Diffusion Tensor Fields.
- IEEE Transactions on Visualisation and Computer Graphics,
, 2000
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Real-Time Techniques for 3D Flow Visualization
, 1998
"... Visualization of three dimensional flow has to overcome a lot of problems to be effective. Among them are occlusion of distant details, lack of directional and depth hints and cluttering. In this paper we present methods which address these problems for realtime graphic representations applicable in ..."
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Cited by 46 (5 self)
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Visualization of three dimensional flow has to overcome a lot of problems to be effective. Among them are occlusion of distant details, lack of directional and depth hints and cluttering. In this paper we present methods which address these problems for realtime graphic representations applicable in virtual environments. We use animated, opacity-mapped streamlines as visualization icon for 3D flow visualization. We present a texture mapping technique to keep the level of texture detail along a streamline nearly constant even when the velocity of the flow varies considerably. An algorithm is described which distributes the dashtubes evenly in space. We apply magic lenses and magic boxes as interaction techniques for investigating densly filled areas without overwhelming the observer with visual detail. Implementation details of these methods and their integration in our virtual environment conclude the paper. CR Categories and Subject Descriptors: I.3.3 [Computer Graphics ]: Picture/Ima...
A Level-Set Method for Flow Visualization
- IN PROCEEDINGS OF VIZ2000, IEEE VISUALIZATION
, 2000
"... In this paper we propose a technique for visualizing steady flow. Using this technique, we first convert the vector field data into a scalar level-set representation. We then analyze the dynamic behavior and subsequent distortion of level-sets and interactively monitor the evolving structures by mea ..."
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Cited by 42 (1 self)
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In this paper we propose a technique for visualizing steady flow. Using this technique, we first convert the vector field data into a scalar level-set representation. We then analyze the dynamic behavior and subsequent distortion of level-sets and interactively monitor the evolving structures by means of texture-based surface rendering. Next, we combine geometrical and topological considerations to derive a multiscale representation and to implement a method for the automatic placement of a sparse set of graphical primitives depicting homogeneous streams in the fields. Using the resulting algorithms, we have built a visualization system that enables us to effectively display the flow direction and its dynamics even for dense 3D fields.
Enhancing depth-perception with flexible volumetric halos
- IEEE Transactions on Visualization and Computer Graphics
"... Abstract—Volumetric data commonly has high depth complexity which makes it difficult to judge spatial relationships accurately. There are many different ways to enhance depth perception, such as shading, contours, and shadows. Artists and illustrators frequently employ halos for this purpose. In thi ..."
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Cited by 40 (5 self)
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Abstract—Volumetric data commonly has high depth complexity which makes it difficult to judge spatial relationships accurately. There are many different ways to enhance depth perception, such as shading, contours, and shadows. Artists and illustrators frequently employ halos for this purpose. In this technique, regions surrounding the edges of certain structures are darkened or brightened which makes it easier to judge occlusion. Based on this concept, we present a flexible method for enhancing and highlighting structures of interest using GPU-based direct volume rendering. Our approach uses an interactively defined halo transfer function to classify structures of interest based on data value, direction, and position. A feature-preserving spreading algorithm is applied to distribute seed values to neighboring locations, generating a controllably smooth field of halo intensities. These halo intensities are then mapped to colors and opacities using a halo profile function. Our method can be used to annotate features at interactive frame rates. Index Terms—Volume rendering, illustrative visualization, halos. 1
Interactive Focus+Context Visualization with Linked 2D/3D Scatterplots
- IN PROC. OF THE INTL. CONFERENCE ON COORDINATED & MULTIPLE VIEWS IN EXPLORATORY VISUALIZATION (CMV 2004
, 2004
"... Scatterplots in 2D and 3D are very useful tools, but also suffer from a number of problems. Overplotting hides the true number of points that are displayed, and showing point clouds in 3D is problematic both in terms of perception and interaction. We propose a ..."
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Cited by 38 (6 self)
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Scatterplots in 2D and 3D are very useful tools, but also suffer from a number of problems. Overplotting hides the true number of points that are displayed, and showing point clouds in 3D is problematic both in terms of perception and interaction. We propose a
A Hybrid Physical/Device-Space Approach for Spatio-Temporally Coherent Interactive Texture Advection on Curved Surfaces
, 2004
"... We propose a novel approach for a dense texture-based visualization of vector fields on curved surfaces. Our texture advection mechanism relies on a Lagrangian particle tracing that is simultaneously computed in the physical space of the object and in the device space of the image plane. This approa ..."
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Cited by 34 (15 self)
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We propose a novel approach for a dense texture-based visualization of vector fields on curved surfaces. Our texture advection mechanism relies on a Lagrangian particle tracing that is simultaneously computed in the physical space of the object and in the device space of the image plane. This approach retains the benefits of previous image-space techniques, such as output sensitivity, independence from surface parameterization or mesh connectivity, and support for dynamic surfaces. At the same time, frame-to-frame coherence is achieved even when the camera position is changed, and potential inflow issues at silhouette lines are overcome. Noise input for texture advection is modeled as a solid 3D texture and constant spatial noise frequency on the image plane is achieved in a memory-efficient way by appropriately scaling the noise in physical space. For the final rendering, we propose color schemes to effectively combine the visualization of surface shape and flow. Hybrid physical/device-space texture advection can be efficiently implemented on GPUs and therefore supports interactive vector field visualization. Finally, we show some examples for typical applications in scientific visualization.
Strategies for Interactive Exploration of 3D Flow Using Evenly-Spaced Illuminated Streamlines
, 2003
"... This paper presents several strategies to interactively explore 3D flow. Based on a fast illuminated streamlines algorithm, standard graphics hardware is sufficient to gain interactive rendering rates. Our approach does not require the user to have any prior knowledge of flow features. After the str ..."
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Cited by 30 (2 self)
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This paper presents several strategies to interactively explore 3D flow. Based on a fast illuminated streamlines algorithm, standard graphics hardware is sufficient to gain interactive rendering rates. Our approach does not require the user to have any prior knowledge of flow features. After the streamlines are computed in a short preprocessing time, the user can interactively change appearance and density of the streamlines to further explore the flow. Most important flow features like velocity or pressure not only can be mapped to all available streamline appearance properties like streamline width, material, opacity, but also to streamline density. To improve spatial perception of the 3D flow we apply techniques based on animation, depth cueing, and halos along a streamline if it is crossed by another streamline in the foreground. Finally, we make intense use of focus+context methods like magic volumes, region of interest driven streamline placing, and spotlights to solve the occlusion problem.
Image-based streamline generation and rendering
- IEEE Trans. Visualization and Computer Graphics
, 2007
"... Abstract—Seeding streamlines in 3D flow fields without considering their projections in screen space can produce visually cluttered rendering results. Streamlines will overlap or intersect with each other in the output image, which makes it difficult for the user to perceive the underlying flow stru ..."
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Cited by 30 (1 self)
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Abstract—Seeding streamlines in 3D flow fields without considering their projections in screen space can produce visually cluttered rendering results. Streamlines will overlap or intersect with each other in the output image, which makes it difficult for the user to perceive the underlying flow structure. This paper presents a method to control the seeding and generation of streamlines in image space to avoid visual cluttering and allow a more flexible exploration of flow fields. In our algorithm, 2D images with depth maps generated by a variety of visualization techniques can be used as input from which seeds are placed and streamlines are generated. The density and rendering styles of streamlines can be flexibly controlled based on various criteria to improve visual clarity. With our image space approach, it is straightforward to implement the level of detail rendering, depth peeling, and stylized rendering of streamlines to allow for more effective visualization of 3D flow fields. Index Terms—Three-dimensional flow visualization, streamlines, streamline seeding, level of detail, depth peeling, stylized rendering. 1
Visualization of Multi-Variate Scientific Data
"... In this state-of-the-art report we discuss relevant research works related to the visualization of complex, multivariate data. We discuss how different techniques take effect at specific stages of the visualization pipeline and how they apply to multi-variate data sets being composed of scalars, vec ..."
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Cited by 26 (8 self)
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In this state-of-the-art report we discuss relevant research works related to the visualization of complex, multivariate data. We discuss how different techniques take effect at specific stages of the visualization pipeline and how they apply to multi-variate data sets being composed of scalars, vectors and tensors. We also provide a categorization of these techniques with the aim for a better overview of related approaches. Based on this classification we highlight combinable and hybrid approaches and focus on techniques that potentially lead towards new directions in visualization research. In the second part of this paper we take a look at recent techniques that are useful for the visualization of complex data sets either because they are general purpose or because they can be adapted to specific problems.
