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26
Piecewise smooth surface reconstruction
, 1994
"... We present a general method for automatic reconstruction of accurate, concise, piecewise smooth surface models from scattered range data. The method can be used in a variety of applications such as reverse engineering — the automatic generation of CAD models from physical objects. Novel aspects of t ..."
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Cited by 304 (13 self)
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We present a general method for automatic reconstruction of accurate, concise, piecewise smooth surface models from scattered range data. The method can be used in a variety of applications such as reverse engineering — the automatic generation of CAD models from physical objects. Novel aspects of the method are its ability to model surfaces of arbitrary topological type and to recover sharp features such as creases and corners. The method has proven to be effective, as demonstrated by a number of examples using both simulated and real data. A key ingredient in the method, and a principal contribution of this paper, is the introduction of a new class of piecewise smooth surface representations based on subdivision. These surfaces have a number of properties that make them ideal for use in surface reconstruction: they are simple to implement, they can model sharp features concisely, and they can be fit to scattered range data using an unconstrained optimization procedure.
FreeForm Shape Design Using Triangulated Surfaces
, 1994
"... We present an approach to modeling with truly mutable yet completely controllable freeform surfaces of arbitrary topology. Surfaces may be pinned down at points and along curves, cut up and smoothly welded back together, and faired and reshaped in the large. This style of control is formulated as a ..."
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Cited by 168 (0 self)
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We present an approach to modeling with truly mutable yet completely controllable freeform surfaces of arbitrary topology. Surfaces may be pinned down at points and along curves, cut up and smoothly welded back together, and faired and reshaped in the large. This style of control is formulated as a constrained shape optimization, with minimization of squared principal curvatures yielding graceful shapes that are free of the parameterization worries accompanying many patchbased approaches. Triangulated point sets are used to approximate these smooth variational surfaces, bridging the gap between patchbased and particlebased representations. Automatic refinement, mesh smoothing, and retriangulation maintain a good computational mesh as the surface shape evolves, and give sample points and surface features much of the freedom to slide around in the surface that oriented particles enjoy. The resulting surface triangulations are constructed and maintained in real time. 1 Introduction ...
Curved PN Triangles
 In Symposium on Interactive 3D Graphics
, 2001
"... quadratically varying normals). To improve the visual quality of existing trianglebased art in realtime entertainment, such as computer games, we propose replacing flat triangles with curved patches and higherorder normal variation. At the hardware level, based only on the three vertices and three ..."
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Cited by 72 (3 self)
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quadratically varying normals). To improve the visual quality of existing trianglebased art in realtime entertainment, such as computer games, we propose replacing flat triangles with curved patches and higherorder normal variation. At the hardware level, based only on the three vertices and three vertex normals of a given flat triangle, we substitute the geometry of a threesided cubic Bézier patch for the triangle’s flat geometry, and a quadratically varying normal for Gouraud shading. These curved pointnormal triangles, or PN triangles, require minimal or no change to existing authoring tools and hardware designs while providing a smoother, though not necessarily everywhere tangent continuous, silhouette and more organic shapes. CR Categories: I.3.5 [surface representation, splines]: I.3.6— graphics data structures
A Survey of Parametric Scattered Data Fitting Using Triangular Interpolants
, 1992
"... This paper has been published as a chapter in "Curve and Surface Design", H. Hagen, (ed), SIAM, 1992 Some of the figures from that paper are missing from this version, as are all of the blackandwhite photographs. There are currently a number of methods for solving variants of the followi ..."
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Cited by 21 (4 self)
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This paper has been published as a chapter in "Curve and Surface Design", H. Hagen, (ed), SIAM, 1992 Some of the figures from that paper are missing from this version, as are all of the blackandwhite photographs. There are currently a number of methods for solving variants of the following problem: Given a triangulated polyhedron P in three space with or without boundary, construct a smooth surface that interpolates the vertices of P. In general, while the methods satisfy the continuity and interpolation requirements of the problem, they often fail to produce pleasing shapes. The purpose of this paper is to present a unifying survey of the published methods, to identify causes of shape defects, and to offer suggestions for improving the aesthetic quality of the interpolants. 8.1 Introduction.
Degenerate Polynomial Patches of Degree 4 and 5 Used for Geometrically Smooth Interpolation in R³
 IN IR , COMPUTER AIDED GEOMETRIC DESIGN 11
"... The problem of interpolating scattered 3D data by a geometrically smooth surface is considered. A completely local method is proposed, based on employing degenerate triangular BernsteinBézier patches. An analysis of these patches is given and some numerical experiments with quartic and quintic patc ..."
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Cited by 12 (1 self)
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The problem of interpolating scattered 3D data by a geometrically smooth surface is considered. A completely local method is proposed, based on employing degenerate triangular BernsteinBézier patches. An analysis of these patches is given and some numerical experiments with quartic and quintic patches are presented.
Smooth parametric surfaces and Nsided patches
 Computation of Curves and Surfaces
, 1990
"... CAGD is reviewed. In particular, we are concerned with how parametric surface patches for CAGD can be pieced together to form a smooth Ck surface. The theory is applied to the problem of filling an nsided hole occurring within a smooth rectangular patch complex. A number of solutions to this proble ..."
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Cited by 12 (0 self)
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CAGD is reviewed. In particular, we are concerned with how parametric surface patches for CAGD can be pieced together to form a smooth Ck surface. The theory is applied to the problem of filling an nsided hole occurring within a smooth rectangular patch complex. A number of solutions to this problem are surveyed. 1.
Surface Approximation Using Geometric Hermite Patches
, 1992
"... A highorderofapproximation surface patch is used to construct continuous, approximating surfaces. This patch, together with a relaxation of tangent plane continuity, is used to approximate offset surfaces, algebraic surfaces, and Spatches. ..."
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Cited by 11 (4 self)
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A highorderofapproximation surface patch is used to construct continuous, approximating surfaces. This patch, together with a relaxation of tangent plane continuity, is used to approximate offset surfaces, algebraic surfaces, and Spatches.
A Testbed For The Comparison Of Parametric Surface Methods
 Curves and Surfaces in Computer Vision and Graphics (Proceedings of SPIE
, 1990
"... There are currently a number of methods for solving variants of the following problem: Given a triangulated polyhedron P in threespace with or without boundary, construct a smooth surface that interpolates the vertices of P. Problems of this variety arise in numerous areas of application such as me ..."
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Cited by 7 (2 self)
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There are currently a number of methods for solving variants of the following problem: Given a triangulated polyhedron P in threespace with or without boundary, construct a smooth surface that interpolates the vertices of P. Problems of this variety arise in numerous areas of application such as medical imaging, scattered data fitting, and geometric modeling. In general, while the techniques satisfy the continuity and interpolation requirements of the problem, they often fail to produce pleasing shapes. Our interest in studying this problem has necessitated the construction of a flexible software testbed that allows rapid implementation and testing of new surface fitting methods and analysis techniques. The testbed is written entirely in the C programming language and is highly portable. Other relevant features of the testbed are discussed, and recommendations for improving the shape characteristics of several interpolation methods are given. 1 MOTIVATION There is much research to be...
Triangular G1 interpolation by 4splitting domain triangles, Computer Aided Geometric Design 17
, 2000
"... HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte p ..."
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Cited by 6 (3 self)
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HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et a ̀ la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. Rapport de Recherche LMCIMAG
Survey of Continuities of Curves and Surfaces
 Computer Graphics forum
, 1994
"... This survey presents an overview to various types of continuity of curves and surfaces, in particular parametric (C n ), visual or geometric (V n , G n ), Frenet frame (F n ), and tangent surface continuity (T n ), and discusses the relation with curve and surface modeling, visibility of (dis)contin ..."
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Cited by 4 (0 self)
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This survey presents an overview to various types of continuity of curves and surfaces, in particular parametric (C n ), visual or geometric (V n , G n ), Frenet frame (F n ), and tangent surface continuity (T n ), and discusses the relation with curve and surface modeling, visibility of (dis)continuities, and graphics rendering algorithms. It is the purpose of this paper to provide an overview of types of continuity, and to put many terms and definitions on a common footing in order to give an understanding of the subject. 1991 Mathematics Subject Classification: 41A15, 65D07, 68U05 1991 Computing Reviews Classification: I.3.5 [Computer Graphics] Computational geometry and object modeling. I.3.7 [Computer Graphics] ThreeDimensional Graphics and Realism. Key Words and Phrases: Curves, Surfaces, Continuity, Shading, Modeling. 1