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48
The quadtree and related hierarchical data structures
 ACM Computing Surveys
, 1984
"... A tutorial survey is presented of the quadtree and related hierarchical data structures. They are based on the principle of recursive decomposition. The emphasis is on the representation of data used in applications in image processing, computer graphics, geographic information systems, and robotics ..."
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Cited by 421 (11 self)
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A tutorial survey is presented of the quadtree and related hierarchical data structures. They are based on the principle of recursive decomposition. The emphasis is on the representation of data used in applications in image processing, computer graphics, geographic information systems, and robotics. There is a greater emphasis on region data (i.e., twodimensional shapes) and to a lesser extent on point, curvilinear, and threedimensional data. A number of operations in which such data structures find use are examined in greater detail.
Imagebased visual hulls
 IN PROCEEDINGS OF ACM SIGGRAPH 2000
, 2000
"... In this paper, we describe an efficient imagebased approach to computing and shading visual hulls from silhouette image data. Our algorithm takes advantage of epipolar geometry and incremental computation to achieve a constant rendering cost per rendered pixel. It does not suffer from the computati ..."
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Cited by 269 (14 self)
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In this paper, we describe an efficient imagebased approach to computing and shading visual hulls from silhouette image data. Our algorithm takes advantage of epipolar geometry and incremental computation to achieve a constant rendering cost per rendered pixel. It does not suffer from the computation complexity, limited resolution, or quantization artifacts of previous volumetric approaches. We demonstrate the use of this algorithm in a realtime virtualized reality application running off a small number of video streams.
Polyhedral Visual Hulls for RealTime Rendering
 In Proceedings of Twelfth Eurographics Workshop on Rendering
, 2001
"... . We present new algorithms for creating and rendering visual hulls in realtime. Unlike voxel or sampled approaches, we compute an exact polyhedral representation for the visual hull directly from the silhouettes. This representation has a number of advantages: 1) it is a viewindependent represent ..."
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Cited by 140 (3 self)
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. We present new algorithms for creating and rendering visual hulls in realtime. Unlike voxel or sampled approaches, we compute an exact polyhedral representation for the visual hull directly from the silhouettes. This representation has a number of advantages: 1) it is a viewindependent representation, 2) it is wellsuited to rendering with graphics hardware, and 3) it can be computed very quickly. We render these visual hulls with a viewdependent texturing strategy, which takes into account visibility information that is computed during the creation of the visual hull. We demonstrate these algorithms in a system that asynchronously renders dynamically created visual hulls in realtime. Our system outperforms similar systems of comparable computational power. 1
Ray Tracing with Cones
, 1984
"... A new approach to ray tracing is introduced. The definition of a "ray" is extended into a cone by including information on the spread angle and the virtual origin. The advantages of this approach, which tries to model light propagation with more fidelity, include a better method of antialiasing, a ..."
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Cited by 98 (3 self)
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A new approach to ray tracing is introduced. The definition of a "ray" is extended into a cone by including information on the spread angle and the virtual origin. The advantages of this approach, which tries to model light propagation with more fidelity, include a better method of antialiasing, a way of calculating fuzzy shadows and dull reflections, a method of calculating the correct level of detail in a procedural model and texture map, and finally, a procedure for faster intersection calculation.
Pipeline Rendering: Interaction And Realism Through HardwareBased MultiPass Rendering
, 1996
"... ..."
Sphere Tracing: A Geometric Method for the Antialiased Ray Tracing of Implicit Surfaces
 The Visual Computer
, 1994
"... Sphere tracing is a new technique for rendering implicit surfaces using geometric distance. Distancebased models are common in computeraided geometric design and in the modeling of articulated figures. Given a function returning the distance to an object, sphere tracing marches along the ray towar ..."
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Cited by 60 (2 self)
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Sphere tracing is a new technique for rendering implicit surfaces using geometric distance. Distancebased models are common in computeraided geometric design and in the modeling of articulated figures. Given a function returning the distance to an object, sphere tracing marches along the ray toward its first intersection in steps guaranteed not to penetrate the implicit surface. Sphere tracing is particularly adept at rendering pathological surfaces. Creased and rough implicit surfaces are defined by functions with discontinuous or undefined derivatives. Current root finding techniques such as LG surfaces and interval analysis require periodic evaluation of the derivative, and their behavior is dependent on the behavior of the derivative. Sphere tracing requires only a bound on the magnitude of the derivative, robustly avoiding problems Manuscript, July 1994. Recommended for publication: The Visual Computer. 570 where the derivative jumps or vanishes. This robustness and scope ...
Radiance Interpolants for Accelerated BoundedError Ray Tracing
 ACM Transactions on Graphics
, 1999
"... this paper, we present a system that exploits objectspace, rayspace, imagespace and temporal coherence to accelerate ray tracing. Our system uses persurface interpolants to approximate radiance, while conservatively bounding error. The techniques we introduce in this paper should enhance both int ..."
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Cited by 53 (5 self)
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this paper, we present a system that exploits objectspace, rayspace, imagespace and temporal coherence to accelerate ray tracing. Our system uses persurface interpolants to approximate radiance, while conservatively bounding error. The techniques we introduce in this paper should enhance both interactive and batch ray tracers.
Constructive Volume Geometry
 Computer Graphics Forum
, 2000
"... We present an algebraic framework, called Constructive Volume Geometry (CVG), for modelling complex spatial objects using combinational operations. By utilising scalar fields as fundamental building blocks, CVG provides highlevel algebraic representations of objects that are defined mathematically ..."
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Cited by 45 (16 self)
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We present an algebraic framework, called Constructive Volume Geometry (CVG), for modelling complex spatial objects using combinational operations. By utilising scalar fields as fundamental building blocks, CVG provides highlevel algebraic representations of objects that are defined mathematically or built upon sampled or simulated datasets. It models amorphous phenomena as well as solid objects, and describes the interior as well as the exterior of objects. We also describe a hierarchical representation scheme for CVG, and a direct rendering method with a new approach for consistent sampling. The work has demonstrated the feasibility of combining a variety of graphics data types in a coherent modelling scheme.
Interactive Boolean Operations for Conceptual Design of 3D Solids
, 1997
"... Interactive modeling of 3D solids is an important and difficult problem in computer graphics. The Constructive Solid Geometry (CSG) modeling scheme is highly attractive for interactive design, due to its support for hierarchical modeling and Boolean operations. Unfortunately, current algorithms for ..."
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Cited by 36 (1 self)
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Interactive modeling of 3D solids is an important and difficult problem in computer graphics. The Constructive Solid Geometry (CSG) modeling scheme is highly attractive for interactive design, due to its support for hierarchical modeling and Boolean operations. Unfortunately, current algorithms for interactive display of CSG models require expensive specialpurpose hardware that is not easily available. In this paper we present a method for interactive display of CSG models using standard, widely available graphics hardware. The method enables the user to interactively modify the affine transformations associated with CSG subobjects. The application we focus upon is that of conceptual design, a stage in the design process in which rapid, interactive visualization of the model and highlevel design operations are of crucial importance, while the objects are relatively simple. The method converts the CSG graph to a novel Convex Differences Aggregate(CDA) representation. The CDA utili...
The Object Instancing Paradigm for Linear Fractal Modeling
 IN PROC. OF GRAPHICS INTERFACE
, 1992
"... The recurrent iterated function system and the Lsystem are two powerful linear fractal models. The main drawback of recurrent iterated function systems is a difficulty in modeling whereas the main drawback of Lsystems is inefficient geometry specification. Iterative and recursive structures ext ..."
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Cited by 32 (4 self)
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The recurrent iterated function system and the Lsystem are two powerful linear fractal models. The main drawback of recurrent iterated function systems is a difficulty in modeling whereas the main drawback of Lsystems is inefficient geometry specification. Iterative and recursive structures extend the object instancing paradigm, allowing it to model linear fractals. Instancing models render faster and are more intuitive to the computer graphics community. A preliminary section briefly introduces the object instancing paradigm and illustrates its ability to model linear fractals. Two main sections summarize recurrent iterated function systems and Lsystems, and provide methods with examples for converting such models to the object instancing paradigm. Finally, a short epilogue describes a particular use of color in the instancing paradigm and the conclusion outlines directions for further research.