Overview
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Digital Geometry Processing
University ofBritish Columbia
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Computer Graphics: ModelingCPCS 524
http://www.cs.ubc.ca/~sheffa/dgp
University ofBritish Columbia
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Geometry Processing
Shape is a basic property of most objects
Geometry processing: computerized modeling & manipulation of 3D geometry
Overview
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Digital Geometry Processing
University ofBritish Columbia
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What is it about?
Creation & manipulation of 3D geometry
University ofBritish Columbia
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Geometry Capture/Reconstruction
Overview
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Digital Geometry Processing
University ofBritish Columbia
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Geometry Capture/Reconstruction
University ofBritish Columbia
Deformation/Animation (physics free)
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Overview
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Digital Geometry Processing
University ofBritish Columbia
Fabrication
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University ofBritish Columbia
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Geometry Representation: Meshes Focus on discrete (polygonal
mesh) models Typically triangular
Why? Simplicity – ease of
description & transfer Base data for rendering
software/hardware Input to most
simulation/analysis tools Output of most acquisition
tools (CT, MRI, laser, etc..)
Overview
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Digital Geometry Processing
University ofBritish Columbia
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Applications
Medicine/Biology
Engineering
Architecture
Games/Movies
University ofBritish Columbia
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Tools?
Use techniques from both Math & CS Differential geometry Computational geometry Graph theory ...
...Combined with a lot of intuition...
Work on real data = Write a lot of code
Overview
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Digital Geometry Processing
University ofBritish Columbia
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Administratia
University ofBritish Columbia
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Course Info Alla Sheffer
Office: ICICS/CS x651e-mail: [email protected] hours by appointment
TA: Shayan Hoshyari (Office hours by appointment)
Web page: www.cs.ubc.ca/~sheffa/dgp Includes lecture slides Piazza page (link from course page)
Info on all changes & news Please check OFTEN
Overview
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Digital Geometry Processing
University ofBritish Columbia
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Grading
45% - Assignments Use existing mesh data-structure/GUI
In-house or open-source 15% - Assignment 1: Mesh Subdivision
Goal: Learn basic mesh data-structure/programming environment
Out 15% - Assignment 2: Mesh Simplification 15% - Assignment 3: Mesh Deformation
University ofBritish Columbia
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Grading
15% - Paper presentation (30min+questions) Presentation requires
Pre-submission: ppt slides (strongly recommended).
Separate core from details Be critical
Grade partly based on peer feedback Upload (private) on piazza after each presentation
Everyone (not just presenter) MUST read paper Prepare at least one question
Overview
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Digital Geometry Processing
University ofBritish Columbia
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Grading
20% - Class participation Classroom participation (ask, answer, opine) Lecture notes (piazza, public) Reading presented papers (before presentation)
Be ready to ask at least one question Learn critical reading
Peer feedback for presentations (piazza, private)
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Grading
25% - Final project Two options
Pre-defined Description on the web end of October
Likely topic: Reconstruction Free-form
e.g. based on paper you or someone else presented Includes proposal (5%), report + results
(15%) & presentation (5%) Presentation scheduled during exam period.
Overview
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Digital Geometry Processing
University ofBritish Columbia
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Course Topics
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Syllabus (provisional)1. Intro to meshes –
terminology, topology, etc..2. Subdivision3. Simplification4. Deformation/Editting5. Differential geometry for
meshes6. Smoothing/Fairing
7. Parameterization & its applications
8. Meshing & Remeshing9. Reconstruction10. Modeling11. Fabrication12. Analysis
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Digital Geometry Processing
University ofBritish Columbia
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Subdivision
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Mesh Simplification
20,000 8,000 2,000
Overview
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Digital Geometry Processing
University ofBritish Columbia
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Deformation
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Differential Geometry
Overview
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Digital Geometry Processing
University ofBritish Columbia
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Smoothing/Fairing
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Parameterization
Overview
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Digital Geometry Processing
University ofBritish Columbia
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Morphing/Properties Transfer
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Remeshing
Overview
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Digital Geometry Processing
University ofBritish Columbia
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Reconstruction
University ofBritish Columbia
Modeling
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Overview
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Digital Geometry Processing
University ofBritish Columbia
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Analysis
Segmentation
Matching
Orientation/View Selection
University ofBritish Columbia
Make it standR. Prévost, E. Whiting, S. Lefebvre,O. Sorkine-Hornung
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Overview
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Digital Geometry Processing
University ofBritish Columbia
Problem formulation
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input model balancedmodel
inner carving shape deformation
University ofBritish Columbia
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Does it stand?
support polygon
centerof mass
gravity
Overview
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Digital Geometry Processing
University ofBritish Columbia
Does it look like the original shape?
Laplacian-based energy [Sorkine 2004]
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Matrix based on initial mesh
Current mesh position
University ofBritish Columbia
RESULTS