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30
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 ..."
Abstract

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.
Feature Sensitive Surface Extraction from Volume Data
"... The representation of geometric objects based on volumetric data structures has advantages in many geometry processing applications that require, e.g., fast surface interrogation or boolean operations such as intersection and union. However, surface based algorithms like shape optimization (fairing) ..."
Abstract

Cited by 120 (8 self)
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The representation of geometric objects based on volumetric data structures has advantages in many geometry processing applications that require, e.g., fast surface interrogation or boolean operations such as intersection and union. However, surface based algorithms like shape optimization (fairing) or freeform modeling often need a topological manifold representation where neighborhood information within the surface is explicitly available. Consequently, it is necessary to find effective conversion algorithms to generate explicit surface descriptions for the geometry which is implicitly defined by a volumetric data set. Since volume data is usually sampled on a regular grid with a given step width, we often observe severe alias artifacts at sharp features on the extracted surfaces. In this paper we present a new technique for surface extraction that performs feature sensitive sampling and thus reduces these alias effects while keeping the simple algorithmic structure of the standard Marching Cubes algorithm. We demonstrate the effectiveness of the new technique with a number of application examples ranging from CSG modeling and simulation to surface reconstruction and remeshing of polygonal models. 1
Interactive Cutaway Illustrations
 Computer Graphics Forum
, 2003
"... In this paper we discuss different approaches to generate cutaway illustrations. The purpose of such a drawing is to allow the viewer to have a look into an otherwise solid opaque object. Traditional methods to draw these kinds of illustrations are evaluated to extract a small and effective set of ..."
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Cited by 42 (0 self)
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In this paper we discuss different approaches to generate cutaway illustrations. The purpose of such a drawing is to allow the viewer to have a look into an otherwise solid opaque object. Traditional methods to draw these kinds of illustrations are evaluated to extract a small and effective set of rules for a computerbased rendering of cutaway illustrations. We show that our approaches are not limited to a specific rendering style but can be successfully combined with a great variety of wellknown artistic or technical illustration techniques. All methods of this paper make use of modern graphics hardware functionality to achieve interactive frame rates.
Approximate Boolean Operations on Freeform Solids
, 2001
"... In this paper we describe a method for computing approximate results of boolean operations (union, intersection, difference) applied to freeform solids bounded by multiresolution subdivision surfaces. ..."
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Cited by 36 (7 self)
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In this paper we describe a method for computing approximate results of boolean operations (union, intersection, difference) applied to freeform solids bounded by multiresolution subdivision surfaces.
HardwareAccelerated Visual Hull Reconstruction and Rendering
 In Graphics Interface 2003
, 2003
"... We present a novel algorithm for simultaneous visual hull reconstruction and rendering by exploiting offtheshelf graphics hardware. The reconstruction is accomplished by projective texture mapping in conjunction with the alpha test. Parallel to the reconstruction, rendering is also carried out in ..."
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Cited by 31 (5 self)
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We present a novel algorithm for simultaneous visual hull reconstruction and rendering by exploiting offtheshelf graphics hardware. The reconstruction is accomplished by projective texture mapping in conjunction with the alpha test. Parallel to the reconstruction, rendering is also carried out in the graphics pipeline. We texture the visual hull viewdependently with the aid of fragment shaders, such as nVIDIA's register combiners. Both reconstruction and rendering are done in a single rendering pass. We achieve frame rates of more than 80 fps on a standard PC equipped with a commodity graphics card. The performance is significantly faster than that of previously reported similar systems.
Hardware Accelerated Voxelization
 Computers and Graphics
, 2000
"... This paper presents a hardware accelerated approach to the voxelization of a wide range of 3D objects, including curves#surfaces, solids, and geometric and volumetric CSG models. The algorithms generate slices of the object models using a surface graphics processor to form the #nal volume repres ..."
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Cited by 21 (1 self)
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This paper presents a hardware accelerated approach to the voxelization of a wide range of 3D objects, including curves#surfaces, solids, and geometric and volumetric CSG models. The algorithms generate slices of the object models using a surface graphics processor to form the #nal volume representations. Boolean operations in a volumetric CSG model are carried out using frame bu#er blending functions. By storing the resulting volume in the 3D texture memory, the algorithms can also volume render the models in real time by 3D texture mapping. As a result, we are able to perform interactive object manipulations and Boolean operations in an intermixed environment of geometric and volumetric objects under a uni#ed volume graphics framework. 1
Fast CSG Voxelization by Frame Buffer Pixel Mapping
, 2000
"... This paper describes a fast algorithm for the volume conversion and rendering of CSG models constructed from both geometric and volumetric primitives. Using 3D texture mapping and frame buffer pixel operations, the algorithm can interactively generate a binary volume of the CSG model. The result can ..."
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Cited by 14 (0 self)
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This paper describes a fast algorithm for the volume conversion and rendering of CSG models constructed from both geometric and volumetric primitives. Using 3D texture mapping and frame buffer pixel operations, the algorithm can interactively generate a binary volume of the CSG model. The result can be used for volume rendering and other applications. Boolean operations are implicitly computed by a PointClassification Map, and implemented by a hardware assisted frame buffer pixel map. The algorithm can be applied to any regions of interest of the model, thus provides a multiresolution rendering solution through dynamic voxelization of the viewing regions. Since no preprocessing is required for any change of the CSG tree, it can be used as an effective rendering tool in a volumetric CSG modeling environment.
Lineartime CSG Rendering of Intersected Convex Objects
 In 10th International Conference in Central Europe on Computer Graphics, Visualization and Computer Vision  WSCG 2002 (2002
, 2002
"... The Sequenced Convex Subtraction (SCS) algorithm is a hardware based multipass imagespace algorithm for general purpose Constructive Solid Geometry (CSG) Rendering. Convex objects combined by volumetric intersection, difference and union are rendered in realtime without brep preprocessing. Open ..."
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Cited by 13 (1 self)
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The Sequenced Convex Subtraction (SCS) algorithm is a hardware based multipass imagespace algorithm for general purpose Constructive Solid Geometry (CSG) Rendering. Convex objects combined by volumetric intersection, difference and union are rendered in realtime without brep preprocessing. OpenGL stencil and depth testing is used to determine the visible surface for each pixel on the screen.
Blist: A Boolean list formulation of CSG trees
, 1998
"... Set membership classification algorithms visit nodes of a CSG tree through a recursive divideandconquer process, which stores intermediate results in a stack, whose depth equals the height, H, of the tree. During this process, the candidate sets is usually subdivided into uniform cells, whose inte ..."
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Cited by 8 (2 self)
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Set membership classification algorithms visit nodes of a CSG tree through a recursive divideandconquer process, which stores intermediate results in a stack, whose depth equals the height, H, of the tree. During this process, the candidate sets is usually subdivided into uniform cells, whose interior is disjoint from primitives' boundaries. Cells inside the CSG object are identified by combining the binary results of classifying them against the primitives. In parallel systems, which allocate a different process to each leaf of the tree, and in algorithms that classify large collections of regularly spaced candidate sets (points, pixels, voxels, rays, or crosssections) against the primitives using forward differences, a separate stack is associated with each candidate or cell. Our new representation for CSG trees, called Blist, distributes the merging operation to the primitives and reduces the storage requirement for each cell to log(H+1) bits. Blist can represent any Boolean expr...
Geometric Algorithms and Data Representation for Solid Freeform Fabrication
, 2000
"... Solid freeform fabrication (SFF) refers to a class of technologies used for making rapid prototypes of 3D parts. With these processes, a triangulated boundary representation of the CAD model of the part is "sliced" into horizontal 2.5D layers of uniform thickness that are successively deposited, ..."
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Cited by 7 (0 self)
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Solid freeform fabrication (SFF) refers to a class of technologies used for making rapid prototypes of 3D parts. With these processes, a triangulated boundary representation of the CAD model of the part is "sliced" into horizontal 2.5D layers of uniform thickness that are successively deposited, hardened, fused, or cut, depending on the particular process, and attached to the layer beneath. The stacked layers form the final part. The current de facto standard interface to these machines, STL, has many shortcomings. We have developed a new "Solid Interchange Format" (SIF) for use as a digital interface to SFF machines. SIF includes constructs for specifying surface and volume properties, precision information, and transmitting unevaluated Boolean trees. We have also develope...