SCI 3750 Computer Graphics and Animation

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SCI 3750 Computer Graphics and Animation
Lecturer Dr. P C Yuen, RRS 723 Text Intera
ctive Computer Graphics Angel, Edward Addison
Wesley 2000 ISBN 0-201- 38597-X Website
http//www.comp.hkbu.edu.hk/sci3750/
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Computer Graphics
Computer graphics is the discipline concerned
with all aspects of producing pictures or images
using a computer. Interactive computer graphics
implies user is in the loop of feedback process
Graphics System
User
React to Change
Display
Change Image
Input Device
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History of Computer Graphics

• Computer Aided Design (CAD) 1965 -
• Simulators (1975-)
• Bitmap graphical user interfaces (late 70s)
• Interactive raster graphics (80s)
• Virtual reality (late 80s - )
• Computer animation
• Visualization
• Computer art
• Web/Internet based graphics

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Applications of Computer Graphics

• Display of Information
• Medicine, Scientific Visualization
• Design
• CAD/CAM
• Simulation
• Flight simulators, Virtual reality, Entertainment
  applications
• User Interface
• GUI, Augmented reality, Games interface

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Computer Graphics vs Image Processing

• Image Processing
• Input a real image
• Output objects model

• Computer Graphics
• Input objects model
• Output realistic image

A sequence of images (frames)
Pictures that move
Computer Animation
Video Processing
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Goals in Computer Graphics and Animation

• Computer Graphics To generate photo-realistic
  images
• 2D graphics, Modeling, rendering, colour,
  Projection etc
• Computer Animation To generate motion-realistic
  video
• 3D modeling, Geometric transformation, motion etc

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The Synthetic-camera Model
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Clipping
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Graphics Conceptual Model
Real Light
Human Eye
Real Object
Human Eye
Graphics System
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The Human Visual System vs The Pinhole camera
Visible Spectrum
Human Visual System
Pinhole camera
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Ray Tracing with Single Point Source
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Ray Tracing with Multiple Light Sources
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Pixels and Image
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Graphics Hardware

• Display
• CRT
• LCD/TFT
• Hardware Display Card
• Direct access to hardware
• Accelerator
• Memory double buffering, RGBA,
• Support driver, API

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Modeling-Rendering Pipeline
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Computer Graphics Terminology

• Rasterization
• Convert the mathematical description of objects
  and their associated colour information to pixels
  on the screen
• Rendering
• A process by which a computer creates images from
  models
• The models, or objects, are constructed from
  geometric primitives, such as points, lines and
  polygons, which are specified by vertices.
• The rendered image consists of pixels drawn on
  the screen.

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Geometry Pipeline