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A Polygonal Approximation to Direct Scalar Volume Rendering
 Computer Graphics
, 1990
"... One method of directly rendering a threedimensional volume of scalar data is to project each cell in a volume onto the screen. Rasterizing a volume cell is more complex than rasterizing a polygon. A method is presented that approximates tetrahedral volume cells with hardware renderable transparent ..."
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Cited by 230 (2 self)
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One method of directly rendering a threedimensional volume of scalar data is to project each cell in a volume onto the screen. Rasterizing a volume cell is more complex than rasterizing a polygon. A method is presented that approximates tetrahedral volume cells with hardware renderable transparent triangles. This method produces results which are visually similar to more exact methods for scalar volume rendering, but is faster and has smaller memory requirements. The method is best suited for display of smoothlychanging data. CR Categories and Subject Descriptors: I.3.0 [Computer Graphics]: General; I.3.5 [Computer Graphics]: Computational Geometry and Object Modeling. Additional Key Words and Phrases: Volume rendering, scientific visualization. 1 Introduction Display of threedimensional scalar volumes has recently become an active area of research. A scalar volume is described by some function f(x; y; z) defined over some region R of threedimensional space. In many scientific ap...
Physically Based Lighting Calculations for Computer Graphics
, 1991
"... Realistic image generation is presented in a theoretical formulation that builds from previous work on the rendering equation. Previous and new solution techniques for the global illumination are discussed in the context of this formulation. The basic ..."
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Cited by 67 (12 self)
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Realistic image generation is presented in a theoretical formulation that builds from previous work on the rendering equation. Previous and new solution techniques for the global illumination are discussed in the context of this formulation. The basic
Flow Volumes For Interactive Vector Field Visualization
, 1993
"... Flow volumes are the volumetric equivalent of stream lines. They provide more information about the vector field being visualized than do stream lines or ribbons. Presented is an efficient method for producing flow volumes, composed of transparently rendered tetrahedra, for use in an interactive sys ..."
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Cited by 62 (8 self)
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Flow volumes are the volumetric equivalent of stream lines. They provide more information about the vector field being visualized than do stream lines or ribbons. Presented is an efficient method for producing flow volumes, composed of transparently rendered tetrahedra, for use in an interactive system. The problems of rendering, subdivision, sorting,compositing artifacts, and user interaction are dealt with. Efficiency comes from rendering only the volume of the smoke, using hardware texturing and compositing.
Direct Volume Visualization of ThreeDimensional Vector Fields
, 1992
"... Current techniques for direct volume visualization offer only the ability to examine scalar fields. However most scientific explorations require the examination of vector and possibly tensor fields as well as numerous scalar fields. This paper describes an algorithm to directly render threedimensio ..."
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Cited by 44 (4 self)
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Current techniques for direct volume visualization offer only the ability to examine scalar fields. However most scientific explorations require the examination of vector and possibly tensor fields as well as numerous scalar fields. This paper describes an algorithm to directly render threedimensional scalar and vector fields. The algorithm uses a combination of sampling and splatting techniques, that are extended to integrate the display of vector field data within the image.
Volume Rendering for Computational Fluid Dynamics: Initial Results
 NASA AMES RESEARCH CENTER
, 1991
"... This work describes a direct volume rendering technique adapted for visualization of results from Computational Fluid Dynamics (CFD) flow solvers. The problem is difficult for at least three reasons: (1) the shapes of the grids, (2) vector as well as scalar data fields, and (3) the types of features ..."
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Cited by 28 (0 self)
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This work describes a direct volume rendering technique adapted for visualization of results from Computational Fluid Dynamics (CFD) flow solvers. The problem is difficult for at least three reasons: (1) the shapes of the grids, (2) vector as well as scalar data fields, and (3) the types of features of interest. In addition, the data set sizes are often between ten and one hundred megabytes, which is large even by volume rendering standards. The method, a ray casting implementation, is chosen for its robustness and adaptability. The software described here differs from other volume renderers in the handling of vector field data and in the techniques for reducing the time required for intersecting rays with grid cell faces. Vector fields are rendered using mappings from the vector field space to three dimensional color spaces plus opacity. Several mappings are considered and the relative merits analyzed. Two techniques for improving the speed of the ordinarily slow ray casting are described. Future developments and improvements are also discussed.
Interactive numerical flow visualization using stream surfaces
 Computing Systems in Engineering
, 1990
"... Threedimensional steady fluid flows are often numerically simulated over multiple overlapping curvilinear arrays of sample points. Such flows are often visualized using tangent curves or streamlines computed through the interpolated velocity field. A stream surface is the locus of an infinite numbe ..."
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Cited by 21 (0 self)
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Threedimensional steady fluid flows are often numerically simulated over multiple overlapping curvilinear arrays of sample points. Such flows are often visualized using tangent curves or streamlines computed through the interpolated velocity field. A stream surface is the locus of an infinite number of streamlines rooted at all points along a short line segment or rake. Stream surfaces can depict the structure of a flow field more effectively than is possible with mere streamline curves, but careful placement of the rakes is needed to most effectively depict the important features of the flow. I have built visualization software which supports the interactive calculation and display of stream surfaces in flow fields represented on composite curvilinear grids. This software exploits several novel methods to improve the speed with which a particle may be advected through a vector field. This is combined with a new algorithm which constructs adaptively sampled polygonal models of stream surfaces. These new methods make stream surfaces a viable tool for interactive numerical flow visualization. Software based ori these methods has been used by scientists at the
Voxels as a Computational Representation of Geometry
 in The Computational Representation of Geometry. SIGGRAPH '94 Course Notes
, 1994
"... This paper is a survey of volume visualization, volume graphics, and volume rendering techniques. It focuses specifically on the use of the voxel representation and volumetric techniques for geometric applications. 1. Introduction Volume data are 3D entities that may have information inside them, ..."
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Cited by 7 (0 self)
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This paper is a survey of volume visualization, volume graphics, and volume rendering techniques. It focuses specifically on the use of the voxel representation and volumetric techniques for geometric applications. 1. Introduction Volume data are 3D entities that may have information inside them, might not consist of surfaces and edges, or might be too voluminous to be represented geometrically . Volume visualization is a method of extracting meaningful information from volumetric data using interactive graphics and imaging, and it is concerned with volume data representation, modeling, manipulation, and rendering [49]. Volume data are obtained by sampling, simulation, or modeling techniques. For example, a sequence of 2D slices obtained from Magnetic Resonance Imaging (MRI) or Computed Tomography (CT) is 3D reconstructed into a volume model and visualized for diagnostic purposes or for planning of treatment or surgery. The same technology is often used with industrial CT for nondes...
A Framework for the Design of Effective Graphics for Scientific Visualization
 NASA Ames Research Center, NAS Systems Division, Applied Research Branch
, 1992
"... This proposal presents a visualization framework, based on a data model, that supports the production of effective graphics for scientific visualization. Visual representations are effective only if they augment comprehension of the increasing amounts of data being generated by modern computer simul ..."
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Cited by 1 (0 self)
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This proposal presents a visualization framework, based on a data model, that supports the production of effective graphics for scientific visualization. Visual representations are effective only if they augment comprehension of the increasing amounts of data being generated by modern computer simulations. These representations are created by taking into account the goals and capabilities of the scientist, the type of data to be displayed, and software and hardware considerations. This framework is embodied in an assistantbased visualization system to guide the scientist in the visualization process. This will improve the quality of the visualizations and decrease the time the scientist is required to spend in generating the visualizations. I intend to prove that such a framework will create a more productive environment for the analysis and interpretation of large, complex data sets. A doctoral dissertation proposal presented to the Department of Computer Science, University of Col...
The Flipping Cube: A Device for Rotating 3D Rasters
, 1991
"... Driven by the prospect of threedimensional rasters as a primary vehicle for future 3D graphics and volumetric imaging, this paper introduces an architecture for realtime rendering of highresolution volumetric images. The Flipping Cube Architecture utilizes parallel memory organization and a uniqu ..."
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Cited by 1 (0 self)
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Driven by the prospect of threedimensional rasters as a primary vehicle for future 3D graphics and volumetric imaging, this paper introduces an architecture for realtime rendering of highresolution volumetric images. The Flipping Cube Architecture utilizes parallel memory organization and a unique data orientation scheme in order to support contention free access to viewing rays. 1.1 Introduction The swift advances in performance, availability and price of computing power, memory, and diskspace are transforming long thought techniques into reality. One typical example to this trend is the revolution taking place in the field of volume graphics. Grasping the feeling of this revolution requires no more than three decades of perspective. The display of computer graphics in the sixties was based on vector drawing devices and an 'object based' approach to scene representation and rendering. A symbolic representation of the scene objects was stored in a displaylist and managed by the c...