Computer Graphics (CG)
• Research in Computer Graphic often tries to
– Find ways to generate pretty pictures
• Rendering
– Find ways to generate desirable shapes
• Modeling
– Find ways to generate believable motions
• Animation
– Find ways to do all these above
• Intuitively and easily
• interactively and efficiently
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Modeling
• How to represent shapes?
In most cases, polygons are used
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Modeling
• How to represent shapes?
Or, polynomials can be used
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NURBS
Modeling
• How to represent shapes?
Usually used for modeling
mechanical parts
In some cases, predefined primitives are used
Constructive Solid Geometry (CSG)
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Modeling
• How to represent shapes?
Without connecting points into polygons
More recently, point-based representation is popular
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Modeling
• How to create these representations?
– Manually using 3D studio or Maya or …
• very flexible
• but time consuming
• and need talent
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http://www.3d.sk/tutorials/Modeling_a_foot_in_Maya.htm
Modeling
• How to create these representations?
–Or we can reuse model parts?!
Kraevoy and Sheffer 2004
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Funkhouser et al. 2004
Modeling
• How to create these representations?
–Or build them directly from real world objects
Issues of handling large geometry
- storing
- registration
- mesh generation
-…
The Digital Michelangelo Project
Laser scanner
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Modeling
• How to create these representations?
–Or build them directly from real world objects
QuickTime™ and a
Cinepak decompressor
are needed to see this picture.
Stereo reconstructions
Tele-immersion lab at UC Berkeley
Reconstructed Tai-chi master
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Animating
• Keyframing
– flexible
– but difficult and time consuming
– need to be talented to create good animations
QuickTime™ and a
mpeg4 decompressor
are needed to see this picture.
Walk cycle
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Animating
• Scripting
– Following a predefined trajectory/movement/event
– Script language
– Used in VR, video games, …
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Animating
• Motion capturing
– Using optical markers
LOR
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Animating
• Motion capturing - beyond joint angles
QuickTime™ and a
DivX 5.0 decompressor
are needed to see this picture.
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Park and Hodgins 2006
Rendering
• Photo-realistic rendering
Find the picture of GT5/Prologue...
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Rendering
• Non-photorealistic rendering
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Rendering
• Image based rendering
QuickTime™ and a
decompressor
are needed to see this picture.
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Rendering
• Other issues: reflection/refraction/soft
shadow
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Rendering
• Other issues: LOD
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Rendering
• Other issues: Fur/shadow/self-ocllusion
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Beyond Pretty Pictures
•
•
•
•
Medical application
Archeology
Education
GPGPU
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haptic
Forma Urbis from Stanford
Now, Let’s take a step back
Computer graphics is a combination of all these and more!
Algorithms
Data structure
Computer
vision
Math
Computational
Geometry
Physics
Art
HCI
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