Computer Graphics Fall 2003

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Computer Graphics (Fall 2003)

• COMS 4160, Lecture 1 Overview and History
• Ravi Ramamoorthi

http//www.cs.columbia.edu/cs4160
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What is Computer Graphics?

• Anything to do with visual representations on a
  computer, including
• Text (Yes !! An early computer graphics problem)
• WIMP GUIs
• Computer Images (CG Computer Pictures)
• 3D Graphics CG special effects, games,
  animations
• Scientific Visualization (CFD images)
• Algorithms, theory (physics, math, computation)
• Display devices, hardware (graphics cards,
  monitors)

The term Computer Graphics was coined by William
Fetter of Boeing in 1960 First graphic system in
mid 1950s USAF SAGE radar data (developed MIT)

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How far weve come TEXT
Manchester Mark I
Display
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From Text to GUIs

• Invented at PARC circa 1975. Used in the Apple
  Macintosh, and now prevalent everywhere.

Windows 1.0
Xerox Star
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And graphical applications

• Presentations (bar charts, graphs, powerpoint)
• Scientific
  Visualization
• (such as in CFD)

Compressible flow around Space shuttle science.gmu
.edu
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Display hardware

• vector displays (1963 modified oscilloscope,
  1974 Evans and Sutherland Picture System)
• raster displays
• 1975 Evans and Sutherland frame buffer
• 1980s cheap frame buffers ? bit-mapped personal
  computers
• 1990s liquid-crystal displays ? laptops
• 2000s micro-mirror projectors ? digital cinema
• other (stereo, head-mounted displays,
  autostereoscopic displays, tactile, haptic, sound)

Slide courtesy Marc Levoy
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Displaying Images in Color

• 3 phosphors Red, Green, Blue. 8 bits/channel,
  color will be 24 bits, approx 17 million colors
• Secondary colors RB Magenta
• RG Yellow
• BG Cyan
• RGB White (PP wont let me draw 3C diag.)
• Grayscale .3R .6G .1B
• Can also use 8 bits lookup table (256 colors)
• Which 256 colors? Color Quantization (eg GIF)

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Drawing Sketchpad (1963)

• Ivan Sutherland, MIT
• First Interactive
• Graphics PhD thesis
• 1988 Turing Award
• For his pioneering and
• visionary contributions
• to computer graphics,
• starting with Sketchpad

• Pop up menus
• Constraint-based drawing
• Hierarchical Modeling

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Paint Systems

• SuperPaint system Richard Shoup, Alvy Ray Smith
  (PARC, 1973-79)
• Nowadays, Photoshop can draw, paint, edit
• Awards to Shoup and Smith SIGGRAPH 1990 Computer
  Graphics Achievement Award, Academy Award (SE)
  with Tom Porter

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Image Processing

• Digitally alter images
• Crop,scale,composite
• Add or remove objects
• Tools are still primitive
• Relight, change materials
• Combine synthetic objects
• Topic of Research

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3D Graphics

• Maybe what we generally consider CG
• Currently important in
• Design (CAD)
• Education, Simulators, VR
• Games
• Entertainment (Movies), Art

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Rendering 1960s (visibility)

• 1960s - the visibility problem
• Roberts (1963), Appel (1967) - hidden-line
  algorithms
• Warnock (1969), Watkins (1970) - hidden-surface
• Sutherland (1974) - visibility sorting

Images from FvDFH, Pixars Shutterbug Slide ideas
for history of Rendering courtesy Marc Levoy
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Rendering 1970s (raster graphics)

• 1970s - raster graphics
• Gouraud (1971) - diffuse lighting
• Phong (1974) - specular lighting
• Blinn (1974) - curved surfaces, texture
• Catmull (1974) - Z-buffer hidden-surface
  algorithm
• Crow (1977) - anti-aliasing

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Rendering (1980s, 90s Global Illumination)

• early 1980s - global illumination
• Whitted (1980) - ray tracing
• Goral, Torrance et al. (1984) radiosity
• Kajiya (1986) - the rendering equation

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New trends non-photorealistic rendering

• Drebin et al. (1988), Levoy (1988) - volume
  rendering
• Haeberli (1990) - impressionistic paint programs
• Salesin et al. (1994-) - automatic pen-and-ink
  illustration
• Meier (1996) - painterly rendering

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New trends Image-Based Rendering

• Chen and Williams (1993) - view interpolation
• McMillan and Bishop (1995) - plenoptic modeling
• Levoy and Hanrahan (1996) - light field rendering

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3D Graphics Pipeline

• Nowadays, increasing reliance on real data
  (range, photographs, motion capture). Many
  research questions.
• Also, Image-based rendering interpolation of
  photographs

Modeling Geometry, Lighting, Materials)
Rendering Shading, Simulation of Light
Animation Kinematics, Dynamics
Images /Movies
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Videos
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Relationship to other courses

• Addition of several graphics courses (next year)
• Other related (but not prerequisite) topics of
  interest Computer vision, user interfaces, pixel
  processing.

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Administrivia of Course

• Website
• Assignments posted on website
• TA
• Office Hours
• Books
• Collaboration Policy
• Grading
• Difficulty/Time required
• Programming
• Background (programming, mathematical)
• Questions?

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Course Outline

• Week 2-3 Transformations and Viewing (Midtm)
• Week 3-5 OpenGL (Ass 1,3,4)
• Week 6,7 Curves (Ass 2, Midtm)
• Week 9-12 Rendering (Final)
• Note
• First part modeling, next part rendering.
• Assignments above relate to content. Dates on
  web page. Midterm in class, Final assignment
  take home
• Remember to send e-mail per assignment 0