CS 395: Adv. Computer Graphics

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CS 395 Adv. Computer Graphics

• This
• is NPR
• Non-
• Photorealistic
• Rendering
• Jack Tumblin
• jet_at_cs.northwestern.edu

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Big Ideas in NPR

• What is the goal of computer graphics?
• A perfect simulation of light transport? No...
• The best picture for every task ?

Drawings, illustrations, paintings...
All Great Pictures
Optical Images (photos, etc.)
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Big Ideas in NPR

• What can artists teach us?
• Imitation (theft) Simulate existing artistic
  media
• paint, charcoal, pencil, watercolor, marble,
• Imitation (theft) Simulate artistic conventions
• learn to draw books
• machine learning on works of art
• analysis of working artists
• Can we help them?
• What can we learn
• from human vision?

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Simulated Watercolor (1997)

• Simulate paper, water, fluid diffusion/soaking,
  drying,...

Computer Generated Watercolor Curtis,Anderson,
Seims, Fleischer,Salesin SIGGRAPH97
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Simulated Watercolor

• Faster blots/splats...

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Pen-And-Ink Winkenbach et al 1994
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Pencil Simulation Sousa 2000

• Sousa, M. C. and Buchanan, J. W.Observational
  Model of Graphite Pencil Materials.Computer
  Graphics Forum, 19(1)27--49, 2000.

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Oil Painting Simulation

• .

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Toon Shaders

• Long history
• Levoy77,
• ...

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NPR Quake Shaders (real time)

• .

Gleicher 2000
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NPR Quake Shaders

• M. Gleicher (U. Wisconsin)
• Cool student projects gone wild
• Downloadable, modifiable, try it!
• http//www.cs.wisc.edu/graphics/Gallery/NPRQuake/w
  hydWeDoIt.html

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3D-Guided, Semantic NPR

• Kowalski et al, Art-Based Rendering
• SIGGRAPH99

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Artistic Styles Herzmann2000

• 
  Machine learning,
• Image analogies, etc....

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Artistic Styles Herzmann2000

• 
  Machine learning,
• Image analogies, etc....

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More NPR Resources

• Great on-line surveys / tutorials Craig Reynolds
• http//www.red3d.com/cwr/npr/
• Great BooksNon-Photorealistic Rendering
  (2001) Bruce Gooch and Amy Gooch, AK Peters
• Great Conference ACM NPAR Non-Photorealistic
  Animation and Rendering
• Great Online Demos Google finds most of them...
• Great Papers http//citeseer.nj.nec.com/cs