Graphics1

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Gentle Introduction to Computer Graphics (1)

• Based on
• David Brogans Introduction to Computer
  Graphics Course Slides, University of Virginia
• Jack van Wijks Computer Graphics Course
  Slides, University of Eindhoven.

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Outline

• Graphics Applications
• What is Computer Graphics
• Representations in Graphics
• Supporting Disciplines

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Graphics Applications

• Entertainment Cinema

A Bugs Life (Pixar)
Pixar Monsters Inc.
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Graphics Applications

• Medical Visualization

The Visible Human Project
MIT Image-Guided Surgery Project
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Graphics Applications

• Scientific Visualization

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Graphics Applications

• Computer Aided Design (CAD)

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Graphics Applications

• Training

Designing Effective Step-By-Step Assembly
Instructions (Maneesh Agrawala et. al)
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Graphics Applications

• Games

GT Racer 3
Polyphony Digital Gran Turismo 3, A Spec
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Graphics Applications

• Games

Circus Atari (Atari)
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Graphics Applications

• The major application that we will be dealing
  with extensively in the next coming lectures is
  that of developing graphical user interfaces
• Windows
• Menus
• Buttons
• Textboxes
• ...

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What is Computer Graphics?

• Computer graphics generating 2D images of a 3D
  world represented in a computer.
• Main tasks
• modeling (shape) creating and representing the
  geometry of objects in the 3D world
• rendering (light, perspective) generating 2D
  images of the objects
• animation (movement) describing how objects
  change in time

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Representations in graphics

• Vector Graphics
• Image is represented by continuous geometric
  objects lines, curves, etc.
• Raster Graphics
• Image is represented as a rectangular grid of
  colored pixels
• PIXEL PIcture ELement

X
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Raster graphics

• Generic
• Image processing techniques
• Geometric Transformation loss of information
• Relatively high processing time
• in terms of the number of pixels
• Realistic images, textures, ...
• Examples Paint, PhotoShop, ...

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Sample Image Processing Techniques

• Edge Detection
• Image Denoising

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Vector graphics

• Graphics objects geometry color
• Relatively low processing time
• in terms of the number of graphic objects
• Geometric transformation possible without loss of
  information (zoom, rotate, )
• Examples PowerPoint, CorelDraw, SVG, ...

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Scalable Vector Graphics (SVG)

• lt?xml version"1.0" standalone"no"?gt
• lt!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
• "http//www.w3.org/Graphics/SVG/1.1/DTD/svg11.dt
  d"gt
• ltsvg width"12cm" height"4cm" viewBox"0 0 1200
  400"
• xmlns"http//www.w3.org/2000/svg"
  version"1.1"gt
• ltdescgtExample polygon01 - star and
  hexagonlt/descgt
• lt!-- Show outline of canvas using 'rect'
  element --gt
• ltrect x"1" y"1" width"1198" height"398"
• fill"none" stroke"blue"
  stroke-width"2" /gt
• ltpolygon fill"red" stroke"blue"
  stroke-width"10"
• points"350,75 379,161 469,161
  397,215
• 423,301 350,250 277,301
  303,215
• 231,161 321,161" /gt
• ltpolygon fill"lime" stroke"blue"
  stroke-width"10"
• points"850,75 958,137.5 958,262.5
• 850,325 742,262.6 742,137.5"
  /gt
• lt/svggt

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In Summary
Image Analysis (pattern recognition)
Image
Math. Model
Image Synthesis(Rendering)
Modeling
Image processing
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Supporting Disciplines

• Computer science (algorithms, data structures,
  software engineering, )
• Mathematics (geometry, numerical, )
• Physics (Optics, mechanics, )
• Psychology (Colour, perception)
• Art and design