jerry tessendorf rhythm & hues studios
TRANSCRIPT
Revised Notes and Slides
www.FinelightVisualTechnology.com
WaterworldTruman Show
Hard RainContact
Cast Away13 Days
Cat in the Hat13th Warrior
TitanicDeep Blue Sea
VirusWorld Is Not
EnoughPeter Pan
Orange CountyFifth Element
Double JeopardyDevil’s Advocate
20K LeaguesX2 Xmen United
Around the World in 80
DaysSphere
Laura Croft Tomb Raider
A Simple WishAir Force OnePearl Harbor
Austin Powers International
Man of MysteryAustin Powers GoldmemberDeep Rising
Al’s Lads
Harry Potter and the Sorcerer’s StoneThe Last SamuraiGuliver’s Travels
The Prince of Egypt
Myst III: ExileMunch’s OdyseeGrim Fandango
Lost Ships
Sinbad Beyond the Veil of MistsTreasures of the Royal Captain
Dawson’s Creek
Its all about
Dispersion• A wavy surface is composed of sinusoidal waves of
various wavelengths
• The speed of each wave depends on its wavelength.
• In the open ocean, longer waves have higher speed.
• Dispersion is the relationship between wavelength L, frequency ω and gravity g.
- ω2 = 2πg/L deep water
- ω2 = 2πg/L tanh(2πd/L) shallow water depth d
- ω2 = 2πg/L (1+(λ/L)2) capillary waves λ
AROSSAirborne Remote Optical Sensing System
• Small plane with an instrumented camera mounted on its nose.
• GPS, INU on the camera
• High bit depth (12 bits) for quantitative dynamic range.
• Builds on past research of many groups.
Duck overpass
Dispersion in the Real World
• Image time series transformed to 3D Power Spectral Density (power vs frequency and wavelength)
• Dispersion in PSD is on a curved surface in the 3D Fourier Space.
• Dispersion easily detected in data.
Building a Wave Field
Sinusoidal wave w/ wavelength L, amplitudes A & B
h(x, t) = A sin
(2πx
L+ ω(L)t
)+ B sin
(2πx
L− ω(L)t
)
Building a Wave Field
Sinusoidal wave w/ wavelength L, amplitudes A & B
Two waves w/ wavelengths L0, L1, amplitudes A0, B0, A1, B1
h(x, t) = A sin
(2πx
L+ ω(L)t
)+ B sin
(2πx
L− ω(L)t
)
h(x, t) = A0 sin
(2πx
L0+ ω(L0)t
)+ B0 sin
(2πx
L0− ω(L0)t
)+ A1 sin
(2πx
L1+ ω(L1)t
)+ B1 sin
(2πx
L1− ω(L1)t
)
Building a Wave Field
For N waves
h(x, t) =N∑
i=1
Ai sin
(2πx
Li+ ω(Li)t
)
+N∑
i=1
Bi sin
(2πx
Li− ω(Li)t
)
Most efficient when using Fast Fourier Transformsfor points x on a regular rectangular grid.
Ocean Surface as a Noise
• Amplitudes Ai , Bi built from oceanographic noise model.
• Variance of random amplitude depend on wavelength Li
• Octaves, power law, other details
• For any frame, propagate using dispersion relationship.
• Efficiently handled with Fast Fourier Transforms (FFT).
Propagation is a linear filter.
Height Slope
RemappedHeight
MinimumEigenvalue
Surface Data Componentsas Animated Textures
Courtesy Bradley Morris, 2001
Choppy Waves• Horizontal displacements from height.
• Follows from Gerstner waves and a complex theoretical guess.
• Sharp peaks and round troughs.
- Peak heights & locations unaltered.
• Drives splash, foam, spray algorithms.
!D(x, t) =1√−∇2
∇ h(x, t)
www.martian-labs.com
Houdini VEX-based geometry/shader
Hydrous Tools
iWaveTotally interactive water surface waves
• Alternate filter for propagation
- 13x13 moving window real space convolution
• Very simple & fast interaction
- obstructions intersecting the water
- sources (wakes)
- shallow water (not possible with fft)
Booth 2019
Revised Notes and Slides
www.FinelightVisualTechnology.com