1
Université de Montréal
2
INRIA Sophia Antipolis
The Simulation of
Paint Cracking and Peeling
E. Paquette
1,2
, P. Poulin
1
, G. Drettakis
2
Université de Montréal
INRIA Sophia Antipolis
Realism
•
Realistic / believable images
•
Simulation (Physics, Mathematics)
•
Precision (perception, measurement)
•
Constraints (time, memory)
•
Tradeoff (increased realism)
e
-
commerce
architecture
effects
Université de Montréal
INRIA Sophia Antipolis
Aging
•
Synthetic objects often look too perfect
•
Deterioration
–
environment
–
everyday use
•
Long term
before
after
Université de Montréal
INRIA Sophia Antipolis
Aging in Computer Graphics
•
Important for realism
–
film
–
virtual reality
–
video games
–
design / prototyping
•
Semi
-
automatic methods
•
Control
after
before
Université de Montréal
INRIA Sophia Antipolis
Peeling
•
Thin layer (paint)
•
Cracks, peels
photo
photo
Université de Montréal
INRIA Sophia Antipolis
Outline
•
Peeling
•
Previous work
•
Simulation
•
Implementation
•
Results
•
Conclusion
Université de Montréal
INRIA Sophia Antipolis
Paint Properties
•
Elasticity
–
can be stretched
•
Tensile stress
–
force required to stretch
•
Tensile strength
–
force required to tear
•
Adhesion strength
–
force required to peel
Université de Montréal
INRIA Sophia Antipolis
Paint Properties
•
Elasticity
–
can be stretched
•
Tensile stress
–
force required to stretch
•
Tensile strength
–
force required to tear
•
Adhesion strength
–
force required to peel
Université de Montréal
INRIA Sophia Antipolis
Paint Properties
•
Elasticity
–
can be stretched
•
Tensile stress
–
force required to stretch
•
Tensile strength
–
force required to tear
•
Adhesion strength
–
force required to peel
Université de Montréal
INRIA Sophia Antipolis
Paint Properties
•
Elasticity
–
can be stretched
•
Tensile stress
–
force required to stretch
•
Tensile strength
–
force required to tear
•
Adhesion strength
–
force required to peel
Université de Montréal
INRIA Sophia Antipolis
Physical Phenomenon
•
Paint
–
dries, shrinks, tensile stress
•
Deterioration
–
moisture, uv, pollution
–
elasticity, strength, adhesion
•
Peeling
–
cracks, loss of adhesion, peels
Université de Montréal
INRIA Sophia Antipolis
Method
•
Simplified model
–
easy control
–
efficiency
•
Surface properties
•
Cracks
–
formation and propagation
•
Loss of adhesion
•
Peeling
synthetic
Université de Montréal
INRIA Sophia Antipolis
Outline
•
Peeling
•
Previous work
•
Simulation
•
Implementation
•
Results
•
Conclusion
Université de Montréal
INRIA Sophia Antipolis
Previous Work
•
Fracture
–
[Norton1991] [Hirota2001]
–
[O'Brien1999] [Smith2000]
•
Cracks
–
[Hirota1999] [Gobron2001]
Université de Montréal
INRIA Sophia Antipolis
Previous Work
Peeling
•
[
Wong1997]
–
tendency (peeling sources, 3D noise)
–
threshold (no simulation)
•
[Gobron2001]
–
cellular automata
–
order in which parts detach
Université de Montréal
INRIA Sophia Antipolis
Previous Work
Peeling
•
[
Wong1997]
–
tendency (peeling sources, 3D noise)
–
threshold (no simulation)
Université de Montréal
INRIA Sophia Antipolis
Previous Work
Peeling
•
[Gobron2001]
–
cellular automata
–
order in which parts detach
1
2
3
4
5
6
Université de Montréal
INRIA Sophia Antipolis
Outline
•
Peeling
•
Previous work
•
Simulation
•
Implementation
•
Results
•
Conclusion
Université de Montréal
INRIA Sophia Antipolis
1
-
stress
4
-
decrease of lateral stress
3
-
movement (strain)
2
-
crack
Overview
•
Top view:
paint layer
Université de Montréal
INRIA Sophia Antipolis
Overview
paint
base
2
-
movement (strain)
3
-
decrease of tensile stress
3
-
increase of shearing stress
4
-
loss of adhesion
1
-
stress
•
Side view:
5
-
peeling
Université de Montréal
INRIA Sophia Antipolis
Implementation
•
Paint properties
–
2D grid
–
directional
•
Cracks
–
sequence of linear segments
–
independent of the grid
Université de Montréal
INRIA Sophia Antipolis
Cracks Control
•
Texture
–
tensile strength
–
white = low
Université de Montréal
INRIA Sophia Antipolis
Creation
•
Perpendicular to the maximum ratio
•
Grid property:
tensile stress
tensile strength
•
New crack
Université de Montréal
INRIA Sophia Antipolis
Propagation
•
Perpendicular to the maximum ratio
•
Grid property:
tensile stress
tensile strength
Université de Montréal
INRIA Sophia Antipolis
Relaxation
•
Perpendicular to the crack
•
Grid property
–
displacement
induced by the
relaxation
Université de Montréal
INRIA Sophia Antipolis
•
Adhesion loss distance
•
Grid property
shearing stress
adhesion strength
Adhesion
•
Loss with respect to ratio
Université de Montréal
INRIA Sophia Antipolis
Peeling
•
Curls perpendicular to the crack
•
Local geometry
•
Control: mesh resolution
3f
2f
1f
q
cross section
mesh
rendered
Université de Montréal
INRIA Sophia Antipolis
Peeling Direction
•
Crack path is
"jaggy"
•
Direction of peeling
is more continuous
photo
Université de Montréal
INRIA Sophia Antipolis
Peeling Direction
•
Direction of peeling
is even more
continuous
photo
Université de Montréal
INRIA Sophia Antipolis
•
Level of detail
•
Fusion metrics
–
loss of adhesion
–
length
–
direction
Segment Fusion
•
Detail information
Université de Montréal
INRIA Sophia Antipolis
Intersection
•
Crack propagation
crack IDs
Université de Montréal
INRIA Sophia Antipolis
Intersection
•
Crack propagation
Université de Montréal
INRIA Sophia Antipolis
Intersection
•
Crack propagation
•
Detect with crack ID
wrong ID
Université de Montréal
INRIA Sophia Antipolis
Intersection
•
Crack propagation
•
Detect with crack ID
•
Join intersecting to
intersected
Université de Montréal
INRIA Sophia Antipolis
Intersection
•
Crack propagation
•
Detect with crack ID
•
Join intersecting to
intersected
•
Compute relaxation
Université de Montréal
INRIA Sophia Antipolis
Intersection
•
Crack propagation
•
Detect with crack ID
•
Join intersecting to
intersected
•
Compute relaxation
•
Split the intersected
crack
Université de Montréal
INRIA Sophia Antipolis
Outline
•
Peeling
•
Previous work
•
Simulation
•
Implementation
•
Results
•
Conclusion
Université de Montréal
INRIA Sophia Antipolis
Simulation System
•
Simulation system
–
crack formation & propagation
–
relaxation and adhesion
•
Cracks information
–
path, widths
•
Rendering
Université de Montréal
INRIA Sophia Antipolis
Maya Plugins
paint
base
color
geometry
cracks
Université de Montréal
INRIA Sophia Antipolis
Outline
•
Peeling
•
Previous work
•
Simulation
•
Implementation
•
Results
•
Conclusion
Université de Montréal
INRIA Sophia Antipolis
Results: Wall
photo
aged
2
nd
view
Université de Montréal
INRIA Sophia Antipolis
Results: Shutters
photo
aged
2
nd
view
Université de Montréal
INRIA Sophia Antipolis
Results: Garage Door
photo
aged
2
nd
view
Université de Montréal
INRIA Sophia Antipolis
Results: Video
•
Propagation
–
wall
–
text (GI 2002)
Université de Montréal
INRIA Sophia Antipolis
Results: Statistics
wall
shutters
garage
nb crack
segments
700
1500
2900
simulation
(400
MHz
)
3 min
20 min
75 min
rendering
(16 x 400 MHz)
3 min
3 min
3 min
Université de Montréal
INRIA Sophia Antipolis
Outline
•
Peeling
•
Previous work
•
Simulation
•
Implementation
•
Results
•
Conclusion
Université de Montréal
INRIA Sophia Antipolis
Conclusion
•
Control through textures
•
Cracks and loss of adhesion
•
Peeling
•
Local geometry
•
Segment fusion
Université de Montréal
INRIA Sophia Antipolis
Extensions
•
Multi
-
layer
–
paint over primer over base surface
•
Multi
-
processing
–
one crack / processor
•
Interaction with other effects
–
example: rust
Université de Montréal
INRIA Sophia Antipolis
Questions?
•
Thanks to
–
Alias|Wavefront
–
NSERC, FCAR, MRI
-
MEQ, FES
-
UdeM
–
Université de Montréal, INRIA, UFJ
–
M. Glisse, A. Reche, C. Puech
Enter the password to open this PDF file:
File name:
-
File size:
-
Title:
-
Author:
-
Subject:
-
Keywords:
-
Creation Date:
-
Modification Date:
-
Creator:
-
PDF Producer:
-
PDF Version:
-
Page Count:
-
Preparing document for printing…
0%
Comments 0
Log in to post a comment