Subdivision Surfaces
|
|
- Annabelle McDowell
- 6 years ago
- Views:
Transcription
1 Subdivision Surfaces 1
2 Geometric Modeling Sometimes need more than polygon meshes Smooth surfaces Traditional geometric modeling used NURBS Non uniform rational B-Spline Demo 2
3 Problems with NURBS A single NURBS patch is either a topological disk, a tube or a torus Must use many NURBS patches to model complex geometry When deforming a surface made of NURBS patches, cracks arise at the seams 3
4 Subdivision Subdivision defines a smooth curve or surface as the limit of a sequence of successive refinements 4
5 Subdivision Surfaces Generalization of spline curves / surfaces Arbitrary control meshes Successive refinement (subdivision) Converges to smooth limit surface Connection between splines and meshes 5
6 Subdivision Surfaces Generalization of spline curves / surfaces Arbitrary control meshes Successive refinement (subdivision) Converges to smooth limit surface Connection between splines and meshes 6
7 Example: Geri s Game (Pixar) Subdivision used for Geri s hands and head Clothing Tie and shoes 7
8 Example: Geri s Game (Pixar) Woody s hand (NURBS) Geri s hand (subdivision) 8
9 Example: Geri s Game (Pixar) Sharp and semi-sharp sharp features 9
10 Example: Games Supported in hardware in DirectX 11 10
11 Subdivision Curves Given a control polygon......find a smooth curve related to that polygon. 11
12 Subdivision Curve Types Approximating Interpolating Corner Cutting 12
13 Approximating 13
14 Approximating Splitting step: split each edge in two 14
15 Approximating Averaging step: relocate each (original) vertex according to some (simple) rule... 15
16 Approximating Start over... 16
17 Approximating...splitting... 17
18 Approximating...averaging... 18
19 Approximating...and so on... 19
20 Approximating If the rule is designed carefully the control polygons will converge to a smooth limit curve! 20
21 Equivalent to Insert single new point at mid-edge Filter entire set of points. Catmull-Clark rule: Filter with (1/8, 6/8, 1/8) 21
22 Corner Cutting Subdivision rule: Insert two new vertices at ¼ and ¾ of each edge Remove the old vertices Connect the new vertices 22
23 B-Spline Curves Piecewise polynomial of degree n B-spline curve control points parameter value basis functions 23
24 B-Spline Curves Distinguish between odd and even points Linear B-spline Odd coefficients (1/2, 1/2) Even coefficient (1) 24
25 B-Spline Curves Quadratic B-Spline (Chaikin) Odd coefficients (¼, ¾) demo Even coefficients (¾, ¼) Cubic B-Spline (Catmull-Clark) Odd coefficients (4/8, 4/8) Even coefficients (1/8, 6/8, 1/8) 25
26 Cubic B-Spline even odd 26
27 Cubic B-Spline odd even 27
28 Cubic B-Spline odd even 28
29 Cubic B-Spline odd even 29
30 Cubic B-Spline odd even 30
31 Cubic B-Spline odd even 31
32 Cubic B-Spline odd even 32
33 Cubic B-Spline odd even 33
34 Cubic B-Spline odd even 34
35 Cubic B-Spline odd even 35
36 Cubic B-Spline odd even 36
37 Cubic B-Spline odd even 37
38 Cubic B-Spline odd even 38
39 Cubic B-Spline odd even 39
40 B-Spline Curves Subdivision rules for control polygon Mask of size n yields C n-1 curve 40
41 Interpolating (4-point Scheme) Keep old vertices Generate new vertices by fitting cubic curve to old vertices C 1 continuous limit it curve 41
42 Interpolating 42
43 Interpolating 43
44 Interpolating 44
45 Interpolating 45
46 Interpolating demo 46
47 Subdivision Surfaces No regular structure as for curves Arbitrary number of edge-neighbors Different subdivision rules for each valence 47
48 Subdivision Rules How the connectivity changes How the geometry changes Old points New points
49 Subdivision Zoo Classification of subdivision schemes Primal Faces are split into sub-faces Dual Vertices are split into multiple l vertices Approximating Interpolating Control points are not interpolated Control points are interpolated 49
50 Subdivision Zoo Classification of subdivision schemes Primal (face split) Ti Triangular meshes Quad dmeshes Approximating Loop(C 2 ) Catmull Clark(C 2 ) Interpolating Mod. Butterfly (C 1 ) Kobbelt (C 1 ) Many more Dual (vertex split) Doo Sabin, Midedge(C 1 ) Biquartic (C 2 )
51 Subdivision Zoo Classification of subdivision schemes Triangles Primal Rectangles Dual Approximating Loop Catmull-Clark Interpolating Butterfly Kobbelt Doo-Sabin Midedge 51
52 Catmull-Clark Clark Subdivision Generalization of bi-cubic B-Splines Primal, approximation subdivision scheme Applied to polygonal meshes Generates G 2 continuous limit it surfaces: C 1 for the set of finite extraordinary points Vertices with valence 4 C 2 continuous everywhere e e e else 52
53 Catmull-Clark Clark Subdivision 53
54 Catmull-Clark Clark Subdivision 54
55 Classic Subdivision Operators Classification of subdivision schemes Triangles Primal Rectangles Dual Approximating Loop Catmull-Clark Interpolating Butterfly Kobbelt Doo-Sabin Midedge 55
56 Loop Subdivision Generalization of box splines Primal, approximating subdivision scheme Applied to triangle meshes Generates G 2 continuous limit it surfaces: C 1 for the set of finite extraordinary points Vertices with valence 6 C 2 continuous everywhere e e e else 56
57 Loop Subdivision 57
58 Loop Subdivision 58
59 Subdivision Zoo Classification of subdivision schemes Triangles Primal Rectangles Dual Approximating Loop Catmull-Clark Interpolating Butterfly Kobbelt Doo-Sabin Midedge 59
60 Doo-Sabin Subdivision Generalization of bi-quadratic B-Splines Dual, approximating subdivision scheme Applied to polygonal meshes Generates G 1 continuous limit it surfaces: C 0 for the set of finite extraordinary points Center of irregular polygons after 1 subdivision step C 1 continuous everywhere e e e else 60
61 Doo-Sabin Subdivision 61
62 Doo-Sabin Subdivision 62
63 Classic Subdivision Operators Classification of subdivision schemes Triangles Primal Rectangles Dual Approximating Loop Catmull-Clark Interpolating Butterfly Kobbelt Doo-Sabin Midedge 63
64 Butterfly Subdivision Primal, interpolating scheme Applied to triangle meshes Generates G 1 continuous limit surfaces: C o for the set of finite extraordinary points Vertices of valence = 3 or > 7 C 1 continuous everywhere else 64
65 Butterfly Subdivision 65
66 Butterfly Subdivision 66
67 Remark Different masks apply on the boundary Example: Loop 67
68 Comparison Doo-Sabin Catmull-Clark Clark Loop Butterfly 68
69 Comparison Subdividing idi a cube Loop result is assymetric, because cube was triangulated first Both Loop and Catmull-Clark are better then Butterfly (C 2 vs. C 1 ) Interpolation vs. smoothness 69
70 Comparison Subdividing a tetrahedron Same insights Severe shrinking for approximating schemes 70
71 Comparison Spot the difference? For smooth meshes with uniform triangle size, different schemes provide very similar results Beware of interpolating schemes for control polygons with sharp features 71
72 So Who Wins? Loop and Catmull-Clark Cl best when interpolation ti is not required Loop best for triangular meshes Catmull-Clark best for quad meshes Don t triangulate and then use Catmull-Clark 72
73 Analysis of Subdivision Invariant neighborhoods How many control-points affect a small neighborhood around a point? Subdivision scheme can be analyzed by looking at a local subdivision matrix 73
74 Local Subdivision Matrix Example: Cubic B-Splines Invariant neighborhood size: 5 74
75 Analysis of Subdivision Analysis via eigen-decomposition of matrix S Compute the eigenvalues and eigenvectors Let be real and X a complete set of eigenvectors 75
76 Analysis of Subdivision Invariance under affine transformations transform(subdivide(p)) = subdivide(transform(p)) 76
77 Analysis of Subdivision Invariance under affine transformations transform(subdivide(p)) = subdivide(transform(p)) Rules have to be affine combinations Even and odd weights each sum to 1 77
78 Analysis of Subdivision Invariance under reversion of point ordering Subdivision rules (matrix rows) have to be symmetric 78
79 Analysis of Subdivision Conclusion: 1 has to be eigenvector of S with eigenvalue λ0=11 79
80 Limit Behavior - Position Any vector is linear combination of eigenvectors: Apply subdivision matrix: rows of X -1 80
81 Limit Behavior - Position For convergence we need Limit vector: independent of j! 81
82 Limit Behavior - Tangent Set origin at a 0 : j Divide by λ1 Limit tangent given by: 82
83 Limit Behavior - Tangent Curves: All eigenvalues of S except λ 0 =1 should be less than λ 1 to ensure existence of a tangent, i.e. Surfaces: Tangents determined by λ 1 and λ 2 83
84 Example: Cubic Splines Subdivision matrix & rules Eigenvalues es 84
85 Example: Cubic Splines Eigenvectors Limit position and tangent 85
86 Properties of Subdivision Flexible modeling Handle surfaces of arbitrary topology Provably smooth limit surfaces Intuitive control point interaction Scalability Level-of-detail rendering Adaptive approximation Usability Compact representation Simple and efficient code 86
87 Beyond Subdivision Surfaces Non-linear subdivision [Schaefer et al. 2008] Idea: replace arithmetic mean with other function de Casteljau with de Casteljau with 87
88 Beyond Subdivision Surfaces T-Splines [Sederberg et al. 2003] Allows control points to be T-junctions Can use less control points Can model different topologies with single surface NURBS T-Splines 88 NURBS T-Splines
89 Beyond Subdivision Surfaces How do you subdivide a teapot? 89
Subdivision Surfaces
Subdivision Surfaces 1 Geometric Modeling Sometimes need more than polygon meshes Smooth surfaces Traditional geometric modeling used NURBS Non uniform rational B-Spline Demo 2 Problems with NURBS A single
More informationCS354 Computer Graphics Surface Representation III. Qixing Huang March 5th 2018
CS354 Computer Graphics Surface Representation III Qixing Huang March 5th 2018 Today s Topic Bspline curve operations (Brief) Knot Insertion/Deletion Subdivision (Focus) Subdivision curves Subdivision
More informationSubdivision Curves and Surfaces
Subdivision Surfaces or How to Generate a Smooth Mesh?? Subdivision Curves and Surfaces Subdivision given polyline(2d)/mesh(3d) recursively modify & add vertices to achieve smooth curve/surface Each iteration
More informationSubdivision. Outline. Key Questions. Subdivision Surfaces. Advanced Computer Graphics (Spring 2013) Video: Geri s Game (outside link)
Advanced Computer Graphics (Spring 03) CS 83, Lecture 7: Subdivision Ravi Ramamoorthi http://inst.eecs.berkeley.edu/~cs83/sp3 Slides courtesy of Szymon Rusinkiewicz, James O Brien with material from Denis
More informationSubdivision overview
Subdivision overview CS4620 Lecture 16 2018 Steve Marschner 1 Introduction: corner cutting Piecewise linear curve too jagged for you? Lop off the corners! results in a curve with twice as many corners
More informationExample: Loop Scheme. Example: Loop Scheme. What makes a good scheme? recursive application leads to a smooth surface.
Example: Loop Scheme What makes a good scheme? recursive application leads to a smooth surface 200, Denis Zorin Example: Loop Scheme Refinement rule 200, Denis Zorin Example: Loop Scheme Two geometric
More informationCurve Corner Cutting
Subdivision ision Techniqueses Spring 2010 1 Curve Corner Cutting Take two points on different edges of a polygon and join them with a line segment. Then, use this line segment to replace all vertices
More informationSubdivision Curves and Surfaces: An Introduction
Subdivision Curves and Surfaces: An Introduction Corner Cutting De Casteljau s and de Boor s algorithms all use corner-cutting procedures. Corner cutting can be local or non-local. A cut is local if it
More informationCurves and Surfaces 2
Curves and Surfaces 2 Computer Graphics Lecture 17 Taku Komura Today More about Bezier and Bsplines de Casteljau s algorithm BSpline : General form de Boor s algorithm Knot insertion NURBS Subdivision
More informationUNIVERSITY OF CALGARY. Subdivision Surfaces. Advanced Geometric Modeling Faramarz Samavati
Subdivision Surfaces Surfaces Having arbitrary Topologies Tensor Product Surfaces Non Tensor Surfaces We can t find u-curves and v-curves in general surfaces General Subdivision Coarse mesh Subdivision
More informationRecursive Subdivision Surfaces for Geometric Modeling
Recursive Subdivision Surfaces for Geometric Modeling Weiyin Ma City University of Hong Kong, Dept. of Manufacturing Engineering & Engineering Management Ahmad Nasri American University of Beirut, Dept.
More informationSubdivision curves and surfaces. Brian Curless CSE 557 Fall 2015
Subdivision curves and surfaces Brian Curless CSE 557 Fall 2015 1 Reading Recommended: Stollnitz, DeRose, and Salesin. Wavelets for Computer Graphics: Theory and Applications, 1996, section 6.1-6.3, 10.2,
More informationCS354 Computer Graphics Surface Representation IV. Qixing Huang March 7th 2018
CS354 Computer Graphics Surface Representation IV Qixing Huang March 7th 2018 Today s Topic Subdivision surfaces Implicit surface representation Subdivision Surfaces Building complex models We can extend
More informationPhysically-Based Modeling and Animation. University of Missouri at Columbia
Overview of Geometric Modeling Overview 3D Shape Primitives: Points Vertices. Curves Lines, polylines, curves. Surfaces Triangle meshes, splines, subdivision surfaces, implicit surfaces, particles. Solids
More informationINF3320 Computer Graphics and Discrete Geometry
INF3320 Computer Graphics and Discrete Geometry More smooth Curves and Surfaces Christopher Dyken, Michael Floater and Martin Reimers 10.11.2010 Page 1 More smooth Curves and Surfaces Akenine-Möller, Haines
More informationSubdivision Surfaces
Subdivision Surfaces CS 4620 Lecture 31 Cornell CS4620 Fall 2015 1 Administration A5 due on Friday Dreamworks visiting Thu/Fri Rest of class Surfaces, Animation, Rendering w/ prior instructor Steve Marschner
More informationSubdivision surfaces. University of Texas at Austin CS384G - Computer Graphics Fall 2010 Don Fussell
Subdivision surfaces University of Texas at Austin CS384G - Computer Graphics Fall 2010 Don Fussell Reading Recommended: Stollnitz, DeRose, and Salesin. Wavelets for Computer Graphics: Theory and Applications,
More informationSubdivision Surfaces. Homework 1: Last Time? Today. Bilinear Patch. Tensor Product. Spline Surfaces / Patches
Homework 1: Questions/Comments? Subdivision Surfaces Last Time? Curves & Surfaces Continuity Definitions Spline Surfaces / Patches Tensor Product Bilinear Patches Bezier Patches Trimming Curves C0, G1,
More informationSurfaces for CAGD. FSP Tutorial. FSP-Seminar, Graz, November
Surfaces for CAGD FSP Tutorial FSP-Seminar, Graz, November 2005 1 Tensor Product Surfaces Given: two curve schemes (Bézier curves or B splines): I: x(u) = m i=0 F i(u)b i, u [a, b], II: x(v) = n j=0 G
More informationNon-Uniform Recursive Doo-Sabin Surfaces (NURDSes)
Non-Uniform Recursive Doo-Sabin Surfaces Zhangjin Huang 1 Guoping Wang 2 1 University of Science and Technology of China 2 Peking University, China SIAM Conference on Geometric and Physical Modeling Doo-Sabin
More information09 - Designing Surfaces. CSCI-GA Computer Graphics - Fall 16 - Daniele Panozzo
9 - Designing Surfaces Triangular surfaces A surface can be discretized by a collection of points and triangles Each triangle is a subset of a plane Every point on the surface can be expressed as an affine
More informationSubdivision Surfaces. Homework 1: Questions on Homework? Last Time? Today. Tensor Product. What s an illegal edge collapse?
Homework 1: Questions/Comments? Subdivision Surfaces Questions on Homework? Last Time? What s an illegal edge collapse? Curves & Surfaces Continuity Definitions 2 3 C0, G1, C1, C 1 a b 4 Interpolation
More informationSubdivision Surfaces. Homework 1: Questions/Comments?
Subdivision Surfaces Homework 1: Questions/Comments? 1 Questions on Homework? What s an illegal edge collapse? 1 2 3 a b 4 7 To be legal, the ring of vertex neighbors must be unique (have no duplicates)!
More informationSubdivision on Arbitrary Meshes: Algorithms and Theory
Subdivision on Arbitrary Meshes: Algorithms and Theory Denis Zorin New York University 719 Broadway, 12th floor, New York, USA E-mail: dzorin@mrl.nyu.edu Subdivision surfaces have become a standard geometric
More informationInterpolatory 3-Subdivision
EUROGRAPHICS 2000 / M. Gross and F.R.A. Hopgood (Guest Editors) Volume 19 (2000), Number 3 Interpolatory 3-Subdivision U. Labsik G. Greiner Computer Graphics Group University of Erlangen-Nuremberg Am Weichselgarten
More informationUsing Semi-Regular 4 8 Meshes for Subdivision Surfaces
Using Semi-Regular 8 Meshes for Subdivision Surfaces Luiz Velho IMPA Instituto de Matemática Pura e Aplicada Abstract. Semi-regular 8 meshes are refinable triangulated quadrangulations. They provide a
More informationVolume Enclosed by Example Subdivision Surfaces
Volume Enclosed by Example Subdivision Surfaces by Jan Hakenberg - May 5th, this document is available at vixra.org and hakenberg.de Abstract Simple meshes such as the cube, tetrahedron, and tripod frequently
More informationAdvanced Graphics. Subdivision Surfaces. Alex Benton, University of Cambridge Supported in part by Google UK, Ltd
Advanced Graphics Subdivision Surfaces Alex Benton, University of Cambridge A.Benton@damtp.cam.ac.uk Supported in part by Google UK, Ltd NURBS patches aren t the greatest NURBS patches are nxm, forming
More informationApproximate Catmull-Clark Patches. Scott Schaefer Charles Loop
Approximate Catmull-Clark Patches Scott Schaefer Charles Loop Approximate Catmull-Clark Patches Scott Schaefer Charles Loop Catmull-Clark Surface ACC-Patches Polygon Models Prevalent in game industry Very
More information3D Modeling techniques
3D Modeling techniques 0. Reconstruction From real data (not covered) 1. Procedural modeling Automatic modeling of a self-similar objects or scenes 2. Interactive modeling Provide tools to computer artists
More informationu 0+u 2 new boundary vertex
Combined Subdivision Schemes for the design of surfaces satisfying boundary conditions Adi Levin School of Mathematical Sciences, Tel-Aviv University, Tel-Aviv 69978, Israel. Email:fadilev@math.tau.ac.ilg
More informationAn Efficient Data Structure for Representing Trilateral/Quadrilateral Subdivision Surfaces
BULGARIAN ACADEMY OF SCIENCES CYBERNETICS AND INFORMATION TECHNOLOGIES Volume 3, No 3 Sofia 203 Print ISSN: 3-9702; Online ISSN: 34-408 DOI: 0.2478/cait-203-0023 An Efficient Data Structure for Representing
More informationSpline Surfaces, Subdivision Surfaces
CS-C3100 Computer Graphics Spline Surfaces, Subdivision Surfaces vectorportal.com Trivia Assignment 1 due this Sunday! Feedback on the starter code, difficulty, etc., much appreciated Put in your README
More informationHoneycomb Subdivision
Honeycomb Subdivision Ergun Akleman and Vinod Srinivasan Visualization Sciences Program, Texas A&M University Abstract In this paper, we introduce a new subdivision scheme which we call honeycomb subdivision.
More informationAdvanced Modeling 2. Katja Bühler, Andrej Varchola, Eduard Gröller. March 24, x(t) z(t)
Advanced Modeling 2 Katja Bühler, Andrej Varchola, Eduard Gröller March 24, 2014 1 Parametric Representations A parametric curve in E 3 is given by x(t) c : c(t) = y(t) ; t I = [a, b] R z(t) where x(t),
More informationComputer Graphics Curves and Surfaces. Matthias Teschner
Computer Graphics Curves and Surfaces Matthias Teschner Outline Introduction Polynomial curves Bézier curves Matrix notation Curve subdivision Differential curve properties Piecewise polynomial curves
More information2D Spline Curves. CS 4620 Lecture 18
2D Spline Curves CS 4620 Lecture 18 2014 Steve Marschner 1 Motivation: smoothness In many applications we need smooth shapes that is, without discontinuities So far we can make things with corners (lines,
More informationInformation Coding / Computer Graphics, ISY, LiTH. Splines
28(69) Splines Originally a drafting tool to create a smooth curve In computer graphics: a curve built from sections, each described by a 2nd or 3rd degree polynomial. Very common in non-real-time graphics,
More informationSmooth Multi-Sided Blending of bi-2 Splines
Smooth Multi-Sided Blending of bi-2 Splines Kȩstutis Karčiauskas Jörg Peters Vilnius University University of Florida K. Karčiauskas, J. Peters (VU, UF) SMI14: Bi-3/4 Caps for bi-2 Splines 1 / 18 Quad
More information1. Introduction. 2. Parametrization of General CCSSs. 3. One-Piece through Interpolation. 4. One-Piece through Boolean Operations
Subdivision Surface based One-Piece Representation Shuhua Lai Department of Computer Science, University of Kentucky Outline. Introduction. Parametrization of General CCSSs 3. One-Piece through Interpolation
More informationJoe Warren, Scott Schaefer Rice University
Joe Warren, Scott Schaefer Rice University Polygons are a ubiquitous modeling primitive in computer graphics. Their popularity is such that special purpose graphics hardware designed to render polygons
More informationQUADRATIC UNIFORM B-SPLINE CURVE REFINEMENT
On-Line Geometric Modeling Notes QUADRATIC UNIFORM B-SPLINE CURVE REFINEMENT Kenneth I. Joy Visualization and Graphics Research Group Department of Computer Science University of California, Davis Overview
More information12.3 Subdivision Surfaces. What is subdivision based representation? Subdivision Surfaces
2.3 Subdivision Surfaces What is subdivision based representation? Subdivision Surfaces Multi-resolution (Scalability) One piece representation (arbitrary topology) What is so special? Numerical stability
More informationNormals of subdivision surfaces and their control polyhedra
Computer Aided Geometric Design 24 (27 112 116 www.elsevier.com/locate/cagd Normals of subdivision surfaces and their control polyhedra I. Ginkel a,j.peters b,,g.umlauf a a University of Kaiserslautern,
More informationFrom curves to surfaces. Parametric surfaces and solid modeling. Extrusions. Surfaces of revolution. So far have discussed spline curves in 2D
From curves to surfaces Parametric surfaces and solid modeling CS 465 Lecture 12 2007 Doug James & Steve Marschner 1 So far have discussed spline curves in 2D it turns out that this already provides of
More informationApproximating Catmull-Clark Subdivision Surfaces with Bicubic Patches
Approximating Catmull-Clark Subdivision Surfaces with Bicubic Patches Charles Loop Microsoft Research Scott Schaefer Texas A&M University April 24, 2007 Technical Report MSR-TR-2007-44 Microsoft Research
More informationREAL-TIME SMOOTH SURFACE CONSTRUCTION ON THE GRAPHICS PROCESSING UNIT
REAL-TIME SMOOTH SURFACE CONSTRUCTION ON THE GRAPHICS PROCESSING UNIT By TIANYUN NI A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS
More informationLocal Modification of Subdivision Surfaces Based on Curved Mesh
Local Modification of Subdivision Surfaces Based on Curved Mesh Yoshimasa Tokuyama Tokyo Polytechnic University tokuyama@image.t-kougei.ac.jp Kouichi Konno Iwate University konno@cis.iwate-u.ac.jp Junji
More informationLecture IV Bézier Curves
Lecture IV Bézier Curves Why Curves? Why Curves? Why Curves? Why Curves? Why Curves? Linear (flat) Curved Easier More pieces Looks ugly Complicated Fewer pieces Looks smooth What is a curve? Intuitively:
More informationModified Catmull-Clark Methods for Modelling, Reparameterization and Grid Generation
Modified Catmull-Clark Methods for Modelling, Reparameterization and Grid Generation Karl-Heinz Brakhage RWTH Aachen, 55 Aachen, Deutschland, Email: brakhage@igpm.rwth-aachen.de Abstract In this paper
More informationSubdivision curves. University of Texas at Austin CS384G - Computer Graphics
Subdivision curves University of Texas at Austin CS384G - Computer Graphics Fall 2010 Don Fussell Reading Recommended: Stollnitz, DeRose, and Salesin. Wavelets for Computer Graphics: Theory and Applications,
More informationTechnical Report. Removing polar rendering artifacts in subdivision surfaces. Ursula H. Augsdörfer, Neil A. Dodgson, Malcolm A. Sabin.
Technical Report UCAM-CL-TR-689 ISSN 1476-2986 Number 689 Computer Laboratory Removing polar rendering artifacts in subdivision surfaces Ursula H. Augsdörfer, Neil A. Dodgson, Malcolm A. Sabin June 2007
More information3D Modeling Parametric Curves & Surfaces. Shandong University Spring 2013
3D Modeling Parametric Curves & Surfaces Shandong University Spring 2013 3D Object Representations Raw data Point cloud Range image Polygon soup Surfaces Mesh Subdivision Parametric Implicit Solids Voxels
More informationSubdivision Surfaces. Course Syllabus. Course Syllabus. Modeling. Equivalence of Representations. 3D Object Representations
Subdivision Surfaces Adam Finkelstein Princeton University COS 426, Spring 2003 Course Syllabus I. Image processing II. Rendering III. Modeling IV. Animation Image Processing (Rusty Coleman, CS426, Fall99)
More informationA subdivision scheme for hexahedral meshes
A subdivision scheme for hexahedral meshes Chandrajit Bajaj Department of Computer Sciences, University of Texas Scott Schaefer Department of Computer Science, Rice University Joe Warren Department of
More informationEfficient GPU Rendering of Subdivision Surfaces. Tim Foley,
Efficient GPU Rendering of Subdivision Surfaces Tim Foley, 2017-03-02 Collaborators Activision Wade Brainerd Stanford Matthias Nießner NVIDIA Manuel Kraemer Henry Moreton 2 Subdivision surfaces are a powerful
More informationAdvanced Geometric Modeling CPSC789
Advanced Geometric Modeling CPSC789 Fall 2004 General information about the course CPSC 789 Advanced Geometric Modeling Fall 2004 Lecture Time and Place ENF 334 TR 9:30 10:45 Instructor : Office: MS 618
More informationComputergrafik. Matthias Zwicker. Herbst 2010
Computergrafik Matthias Zwicker Universität Bern Herbst 2010 Today Curves NURBS Surfaces Parametric surfaces Bilinear patch Bicubic Bézier patch Advanced surface modeling Piecewise Bézier curves Each segment
More informationNon-Uniform Recursive Doo-Sabin Surfaces
Non-Uniform Recursive Doo-Sabin Surfaces Zhangjin Huang a,b,c,, Guoping Wang d,e a School of Computer Science and Technology, University of Science and Technology of China, PR China b Key Laboratory of
More informationCurves, Surfaces and Recursive Subdivision
Department of Computer Sciences Graphics Fall 25 (Lecture ) Curves, Surfaces and Recursive Subdivision Conics: Curves and Quadrics: Surfaces Implicit form arametric form Rational Bézier Forms Recursive
More informationAdvanced Computer Graphics
Advanced Computer Graphics Lecture 2: Modeling (1): Polygon Meshes Bernhard Jung TU-BAF, Summer 2007 Overview Computer Graphics Icon: Utah teapot Polygon Meshes Subdivision Polygon Mesh Optimization high-level:
More informationG 2 Bezier Crust on Quad Subdivision Surfaces
Pacific Graphics (2013) B. Levy, X. Tong, and K. Yin (Editors) Short Papers G 2 Bezier Crust on Quad Subdivision Surfaces paper 1348 Figure 1: Two examples of Bezier crust applied on Catmull-Clark subdivision
More informationHierarchical Grid Conversion
Hierarchical Grid Conversion Ali Mahdavi-Amiri, Erika Harrison, Faramarz Samavati Abstract Hierarchical grids appear in various applications in computer graphics such as subdivision and multiresolution
More informationA Unified Framework for Primal/Dual Quadrilateral Subdivision Schemes
A Unified Framework for Primal/Dual Quadrilateral Subdivision Schemes Denis Zorin NYU Peter Schröder Caltech Abstract Most commonly used subdivision schemes are of primal type, i.e., they split faces.
More informationComputergrafik. Matthias Zwicker Universität Bern Herbst 2016
Computergrafik Matthias Zwicker Universität Bern Herbst 2016 Today Curves NURBS Surfaces Parametric surfaces Bilinear patch Bicubic Bézier patch Advanced surface modeling 2 Piecewise Bézier curves Each
More information2D Spline Curves. CS 4620 Lecture 13
2D Spline Curves CS 4620 Lecture 13 2008 Steve Marschner 1 Motivation: smoothness In many applications we need smooth shapes [Boeing] that is, without discontinuities So far we can make things with corners
More informationBézier and B-spline volumes Project of Dissertation
Department of Algebra, Geometry and Didactics of Mathematics Faculty of Mathemathics, Physics and Informatics Comenius University, Bratislava Bézier and B-spline volumes Project of Dissertation Martin
More informationNormals of subdivision surfaces and their control polyhedra
Normals of subdivision surfaces and their control polyhedra I. Ginkel, a, J. Peters b, and G. Umlauf a, a University of Kaiserslautern, Germany b University of Florida, Gainesville, FL, USA Abstract For
More informationGrid Generation and Grid Conversion by Subdivision Schemes
Grid Generation and Grid Conversion by Subdivision Schemes Karl Heinz Brakhage Institute for Geometry and Applied Mathematics RWTH Aachen University D-55 Aachen brakhage@igpm.rwth-aachen.de Abstract In
More informationGeneralizing the C 4 Four-directional Box Spline to Surfaces of Arbitrary Topology Luiz Velho Abstract. In this paper we introduce a new scheme that g
Generalizing the C 4 Four-directional Box Spline to Surfaces of Arbitrary Topology Luiz Velho Abstract. In this paper we introduce a new scheme that generalizes the four-directional box spline of class
More information08 - Designing Approximating Curves
08 - Designing Approximating Curves Acknowledgement: Olga Sorkine-Hornung, Alexander Sorkine-Hornung, Ilya Baran Last time Interpolating curves Monomials Lagrange Hermite Different control types Polynomials
More informationSubdivision of Curves and Surfaces: An Overview
Subdivision of Curves and Surfaces: An Overview Ben Herbst, Karin M Hunter, Emile Rossouw Applied Mathematics, Department of Mathematical Sciences, University of Stellenbosch, Private Bag X1, Matieland,
More informationIntroduction to Geometry. Computer Graphics CMU /15-662
Introduction to Geometry Computer Graphics CMU 15-462/15-662 Assignment 2: 3D Modeling You will be able to create your own models (This mesh was created in Scotty3D in about 5 minutes... you can do much
More informationGeometric modeling 1
Geometric Modeling 1 Look around the room. To make a 3D model of a room requires modeling every single object you can see. Leaving out smaller objects (clutter) makes the room seem sterile and unrealistic
More informationA Continuous 3-D Medial Shape Model with Branching
A Continuous 3-D Medial Shape Model with Branching Timothy B. Terriberry Guido Gerig Outline Introduction The Generic 3-D Medial Axis Review of Subdivision Surfaces Boundary Reconstruction Edge Curves
More informationTo appear in Computer-Aided Design Revised June 18, J-splines
To appear in Computer-Aided Design Revised June 18, 2008 J-splines Jarek Rossignac School of Interactive Computing, College of Computing, Georgia Institute of Technology, Atlanta, GA http://www.gvu.gatech.edu/~jarek
More informationSmooth Surfaces from 4-sided Facets
Smooth Surfaces from -sided Facets T. L. Ni, Y. Yeo, A. Myles, V. Goel and J. Peters Abstract We present a fast algorithm for converting quad meshes on the GPU to smooth surfaces. Meshes with 1,000 input
More informationMathematical Tools in Computer Graphics with C# Implementations Table of Contents
Mathematical Tools in Computer Graphics with C# Implementations by Hardy Alexandre, Willi-Hans Steeb, World Scientific Publishing Company, Incorporated, 2008 Table of Contents List of Figures Notation
More informationCS-184: Computer Graphics
CS-184: Computer Graphics Lecture #12: Curves and Surfaces Prof. James O Brien University of California, Berkeley V2007-F-12-1.0 Today General curve and surface representations Splines and other polynomial
More information3D Modeling Parametric Curves & Surfaces
3D Modeling Parametric Curves & Surfaces Shandong University Spring 2012 3D Object Representations Raw data Point cloud Range image Polygon soup Solids Voxels BSP tree CSG Sweep Surfaces Mesh Subdivision
More informationSubdivision based Interpolation with Shape Control
Subdivision based Interpolation with Shape Control Fengtao Fan University of Kentucky Deparment of Computer Science Lexington, KY 40506, USA ffan2@uky.edu Fuhua (Frank) Cheng University of Kentucky Deparment
More informationApproximating Catmull-Clark Subdivision Surfaces with Bicubic Patches
Approximating Catmull-Clark Subdivision Surfaces with Bicubic Patches CHARLES LOOP Microsoft Research and SCOTT SCHAEFER Texas A&M University We present a simple and computationally efficient algorithm
More informationRemoving Polar Rendering Artifacts in Subdivision Surfaces
This is an electronic version of an article published in Journal of Graphics, GPU, and Game Tools, Volume 14, Issue 2 pp. 61-76, DOI: 10.1080/2151237X.2009.10129278. The Journal of Graphics, GPU, and Game
More informationUntil now we have worked with flat entities such as lines and flat polygons. Fit well with graphics hardware Mathematically simple
Curves and surfaces Escaping Flatland Until now we have worked with flat entities such as lines and flat polygons Fit well with graphics hardware Mathematically simple But the world is not composed of
More informationFast Rendering of Subdivision Surfaces
Fast Rendering of Subdivision Surfaces Kari Pulli (Univ. of Washington, Seattle, WA) Mark Segal (SGI) Abstract Subdivision surfaces provide a curved surface representation that is useful in a number of
More informationCurves and Surfaces for Computer-Aided Geometric Design
Curves and Surfaces for Computer-Aided Geometric Design A Practical Guide Fourth Edition Gerald Farin Department of Computer Science Arizona State University Tempe, Arizona /ACADEMIC PRESS I San Diego
More informationG 2 Interpolation for Polar Surfaces
1 G 2 Interpolation for Polar Surfaces Jianzhong Wang 1, Fuhua Cheng 2,3 1 University of Kentucky, jwangf@uky.edu 2 University of Kentucky, cheng@cs.uky.edu 3 National Tsinhua University ABSTRACT In this
More informationCOMPUTER AIDED GEOMETRIC DESIGN. Thomas W. Sederberg
COMPUTER AIDED GEOMETRIC DESIGN Thomas W. Sederberg January 31, 2011 ii T. W. Sederberg iii Preface This semester is the 24 th time I have taught a course at Brigham Young University titled, Computer Aided
More informationPolar Embedded Catmull-Clark Subdivision Surface
Polar Embedded Catmull-Clark Subdivision Surface Anonymous submission Abstract In this paper, a new subdivision scheme with Polar embedded Catmull-Clark mesh structure is presented. In this new subdivision
More informationTernary Butterfly Subdivision
Ternary Butterfly Subdivision Ruotian Ling a,b Xiaonan Luo b Zhongxian Chen b,c a Department of Computer Science, The University of Hong Kong b Computer Application Institute, Sun Yat-sen University c
More information2001, Denis Zorin. Subdivision Surfaces
200, Denis Zorin Subdivision Surfaces Example: Loop Scheme What makes a good scheme? recursive application leads to a smooth surface 200, Denis Zorin Example: Loop Scheme Refinement rule 200, Denis Zorin
More informationB-spline Curves. Smoother than other curve forms
Curves and Surfaces B-spline Curves These curves are approximating rather than interpolating curves. The curves come close to, but may not actually pass through, the control points. Usually used as multiple,
More informationCurves and Surfaces 1
Curves and Surfaces 1 Representation of Curves & Surfaces Polygon Meshes Parametric Cubic Curves Parametric Bi-Cubic Surfaces Quadric Surfaces Specialized Modeling Techniques 2 The Teapot 3 Representing
More informationCS130 : Computer Graphics Curves (cont.) Tamar Shinar Computer Science & Engineering UC Riverside
CS130 : Computer Graphics Curves (cont.) Tamar Shinar Computer Science & Engineering UC Riverside Blending Functions Blending functions are more convenient basis than monomial basis canonical form (monomial
More informationGeometry Processing & Geometric Queries. Computer Graphics CMU /15-662
Geometry Processing & Geometric Queries Computer Graphics CMU 15-462/15-662 Last time: Meshes & Manifolds Mathematical description of geometry - simplifying assumption: manifold - for polygon meshes: fans,
More informationModeling. Simulating the Everyday World
Modeling Simulating the Everyday World Three broad areas: Modeling (Geometric) = Shape Animation = Motion/Behavior Rendering = Appearance Page 1 Geometric Modeling 1. How to represent 3d shapes Polygonal
More informationA subdivision scheme for hexahedral meshes
A subdivision scheme for hexahedral meshes Chandrajit Bajaj Department of Computer Sciences, University of Texas Scott Schaefer Department of Computer Science, Rice University Joe Warren Department of
More informationSubdivision surfaces for CAD: integration through parameterization and local correction
Workshop: New trends in subdivision and related applications September 4 7, 212 Department of Mathematics and Applications, University of Milano-Bicocca, Italy Subdivision surfaces for CAD: integration
More informationSmooth Patching of Refined Triangulations
Smooth Patching of Refined Triangulations Jörg Peters July, 200 Abstract This paper presents a simple algorithm for associating a smooth, low degree polynomial surface with triangulations whose extraordinary
More informationOn Smooth Bicubic Surfaces from Quad Meshes
On Smooth Bicubic Surfaces from Quad Meshes Jianhua Fan and Jörg Peters Dept CISE, University of Florida Abstract. Determining the least m such that one m m bi-cubic macropatch per quadrilateral offers
More information