[PDF] - Memo rial Luiz V elho Overview Education B.S. Degree - PDF Document

SLIDE 1 Memo rial Luiz V elho

SLIDE 2 Overview

Education

{ B.S. Degree

ESDI

{ M.S. Degree

MIT

Media Lab { Ph.D. Degree

U.

T

ronto
Resea

rch { Image Dithering { Multiresolution P ainting { Mo deling with Implicit Objects { P

lygonization

Metho ds

Exp

erience { F AM { Glob

SLIDE 3 B.S. Degree

ESDI

Computer Graphics and Design Investigation

f

T echnology and Applications

f

CG { Field Study

CAD

in Brazil { Exp eriment with Designers

P

attern Creation (Simmetry Groups) { Computer Animation

Wireframe

3D System (Development and Pro duction)

SLIDE 4 Exp eriment with Graphic Designers

Simmetry

Groups

SLIDE 5 3D Wireframe Animation First Computer Generated Animation in Brazil

SLIDE 6 M.S. Degree

MIT

Media Lab Computer Animation Pro cedural Animation System { Animation Abstractions

Scripts
T

racks { System Architecture

Extension

Language

Distributed

Computation

Multiple

Windo ws (X11) { Dierent Levels

Autho

ring

Interaction

SLIDE 7 Scripts System

T

ypical w

rking

conguration

SLIDE 8 Animation Example

Inverse

Kinematics

F
rw

a rd Dynamics

Collision

Detection

SLIDE 9 Ph.D. Degree

U.
f

T

ronto

Geometric Mo deling Mo deling F ramew

rk

based

n

Piecewise Implicit Descriptions

Cha

racterization

f

Implicit Mo dels { T ubula r Neigb

rho
d
Smo
th

Implicit F unction Mo del { Multiscale Edge Analysis / Synthesis

Hiera

rchical Implicit Rep resentation { Multiscale B-Spline Basis

Adapted

Simplicial Decomp

sition

{ Physics-Based Simulation Complete F ramew

rk

* Decomp

sition

+ Adaptation Conversion

f

Rep resentations Implicit $ P a rametric

.

V

lumetric

SLIDE 10 Smo

th

Implicit F unction Cha racteristic F unction W avelet Maxima V alues V

lumetric

Implicit F unction

SLIDE 11 Hiera rchical Rep resentation B-spline Pyramid

f

the Implicit F unction B-spline F unctions

SLIDE 12 App ro ximate Conversion Initial and Final Mesh fo r Solid Shap e Final Mesh fo r Hollo w Shap e Bounda ry derived from the Mesh

SLIDE 13 Image Dithering

Pyramid

Dither

Dither

with Space Filing Curves { Basic { Adaptive { Colo r { Graphic Eects

SLIDE 14 Pyramid Dither

Image

Pyramid

Recursive

Quantization W = P w i

Distribution
f

Intensities w i = d i + r i { Deterministic Comp

nent

d i = b(v i =V ))W c { Probabilistc Comp

nent

r i = 1 with Probabilit y e i

Analysis

{ Optimal Lo cal and Global Quantization { Deterministic T erm Dominates Globally { Probabilistic T erm Dominates Lo cally

SLIDE 15 Example

Photographic

Image

Computer

Generated Image

SLIDE 16 Space Filling Curve Dither

SF

C Dither { Ap erio dic { V a riable Cluster { Anisotropic * Fills T echnology Gap * Reop ened the a rea

SLIDE 17 SF C: Basic Metho d

Image

Scan

Image

P a rtition

P

attern Generation

SLIDE 18 SF C: Adaptation

Pixel

Centering

V

a riable Cluster Size

Adaptation

F unction (image gradient)

SLIDE 19 SF C: Colo r

Co

rrelated Cluster P

sitioning

SLIDE 20 Algo rithm 1. Sub division

f

Image into Cells 2. Computation

f

Average Intensit y 3. Generation

f

Dot P atterns

SLIDE 21 Examples

Photograph
Ca

rto

n

SLIDE 22 2D P aint

W

avelet P aint

Multiresolution

T extures

p

ened the a rea

SLIDE 23 W avelet P aint Multiresolution P ainting Pro cess mo dify image at level x # " move up

r

do wn a level

Computational

Supp

rt

{ P ainting

ver

Multiple Levels { Multiresolution Comp

siting

{ B-Spline W avelets

f

degree n

Advantages

{ Quick Changes (la rge a reas) { Unlimited Detail

SLIDE 24 Example

P

ainting and Zo

ming

SLIDE 25 Multiresolution T extures

Pro

cedural P aint-Brushes

New

T

l,

designed fo r MPS { Complex P atterns { Automatic Generation

f

Detail Mechanisms

Pro

cedural Bandpass Pyramid: f (u; v ; s) { Base Pro cedure

inital

app ea reance

Called

during P ainting { Detail Pro cedure

add

detail

Called

During Magnication

T

exture Alpha Channel:

f

{ T exture Propagation { Lazy Evaluation

SLIDE 26 Example

Ro

ck T exture

Mixture
f

T extures

SLIDE 27 Implicit Surfaces

Multiscale

Rep resentation

Surface

Defo rmation and Animation

T

exture Mapping

SLIDE 28 Multiscale Rep resentation

f

Implicit Surfaces

Multiscale

B-Spline Mo del { Piecewise { Structured { Hiera rchical

Rep

resentation f = X j g j = X j @ X i a i;j

2

j ;k i (x) 1 A where a i;j =< F ; e

j;k

i >

Computation

{ Laplacian Decomp

sition
Data

Structure { Spatial Hash T able H = fa i;j ;

i

g Applications { Conversion V

lumetric
Implict

{ V a riable Level

f

Detail Mo del { F ast Ra y T racing / V

lume

Rendering

SLIDE 29 Example: Noisy Sphere

Slices
f

the Densit y F unction

B-Spline

Pyramid 32

32

16

16

8

8
Surface

Ra y-T raced

SLIDE 30 Surface Defo rmation and Animation

System

Pip eline USER INPUT IMPLICIT OBJECT VISUALIZA TION GEOMETRIC D A T A SPRING-MASS MESH D YNAMICS SIMULA TION MESH GENERA TION

Mesh

Adaptation Algo rithm

SLIDE 31 Example: Cylinder

Mesh

Adaptation Initial and Defo rmed Meshes

Dynamics

Simulation

SLIDE 32 T exture

f

Implicit Surfaces 2D T exture Mapping with P a rticle Systems

Projection

T exture Supp

rt

Object # Implicit Object

Mapping

F unction { F

rce

Field d 2 x dt 2 +

dx

dt + rF =

Computation

{ P a rticle System

Control

{ Global

Relative

P

sitioning
Blending
f

Gradient Fields { Lo cal

A

ttracto rs / Repulso rs

SLIDE 33 Example: Cok e Bottle

Source

T exture

P

a rticle T rajecto ries and T extured Object

SLIDE 34 P

lygonization
P
lygonization
f

Implicit Surfaces using Simplicial Decomp

sitions
Physics-Based

P

lygonization
f

Implicit Surfaces

Unied

P ath-Based P

lygonization
f

P a rametric and Implict Surfaces

SLIDE 35 Simplicial P

lygonization
Adaptive

P

lygonization
Metho

d { Recursive Simplicial Decomp

sition

{ Bounda ry Constraints

Sub

division

f

the Cub e

F

ace and Edge Constraints

SLIDE 36 Example: Blobb y

P
lygonization
Detail

SLIDE 37 Physics-Based P

lygonization
Quasi-Regula

r T riangulation { F at T riangles { Optimal Sample Placement

Physics-Based

Metho d { Sp ring-Mass Meshes { Mesh Adaptation

Internal

F

rces

(mesh)

External

F

rces

(gradient eld)

Induced

P

lygonal

Mesh { Dual

SLIDE 38 Example: Cylinder

Mesh

Adaptation

P
lygonal

Mesh

SLIDE 39 P ath-Based P

lygonization
Unied

F ramew

rk

{ P a rametric { Implicit

Adaptive

T riangulation { Consistent T

p
logy
Hiera

rchical Mesh { Multiresolution { Progressive

Op

erations { Multiresolution P ath Sampling

1 2 1 2 2

p q t t t L R S

{ Cell Structuring

n
n1
1
2

n2 n1 n3

1
2
3

n2

SLIDE 40 Example: T

rus
P

a rametric

Implicit