Introduction to Computer Graphics

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Introduction to Computer Graphics

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Contents

• Introduction
• What is Computer Graphics?
• Applications
• Display of Information
• Design
• Simulation
• Computer Art
• Entertainment
• Graphics Systems Models
• Graphics System
• Human Visual System
• Pinhole Camera
• Synthetic-Camera Model
• Graphics Architectures

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What is Computer Graphics? (1/2)

• Definition
• Producing pictures or images using a computer
• Example
• Starship Troopers Tango-Urilla, Death From Above
• Batman Robin The Love Dust

Courtesy of Buf Compagnie
Courtesy of Tippet Studio
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What is Computer Graphics? (2/2)

• Modeling
• Representing 3D objects
• Rendering
• Constructing 2D images from 3D models
• Animation
• Simulating changes over time

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Applications

• Display of Information
• Design
• Simulation
• Computer Art
• Entertainment

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Display of Information

• Graphics for Scientific, Engineering, and Medical
  Data

Medical Image
Nebula
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Design

• Graphics for Engineering and Architectural System
• Design of Building, Automobile, Aircraft, Machine
  etc.

AutoCAD 2002
Interior Design
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Simulation

• Computer-Generated Models of Physical, Financial
  and Economic Systems for Educational Aids

Flight Simulator
Mars Rover Simulator
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Computer Art

• Graphics for Artist

Metacreation Painter
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Entertainment

• Graphics for Movie, Game, VR etc.

Final Fantasy
Online Game
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Graphics Systems Models

• Graphics System
• Human Visual System
• Pinhole Camera
• Synthetic-Camera Model
• Graphics Architectures

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Graphics System (1/2)
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Graphics System (2/2)

• Pixel
• Picture element
• Raster
• Array of pixels
• Frame Buffer
• Memory where pixels stored
• Depth of Frame Buffer
• Number of bits that are used for each pixel (ex.
  8-bit-depth ? 28 (256) colors, 24 or more bits
  per pixel ? RGB-color )
• Resolution
• Number of pixels in frame buffer
• Rasterization (Scan Conversion)
• Converting of geometric entities (such as lines,
  circles, and polygons) to pixel assignment in
  frame buffer
• Refresh Rate
• Rate of retracing on displays

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Human Visual System
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Pinhole Camera (1/2)
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Pinhole Camera (2/2)

• Side View
• (xp, yp, zp) projection point
• Angle of View (Field of View)

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Synthetic-Camera Model (1/2)

• Imaging with the Synthetic Camera
• Projector
• Line from a point on the object to the
• center of the lens
• Center of projection
• Center of the lens
• Projection plane
• film plane that moved in front of the lens
• Equivalent Views of Image Formation

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Synthetic-Camera Model (2/2)

• Clipping
• Clipping window (clipping rectangle)
• Limited size of the image ? because of the angle
  of view

Clipping with window in initial position
Clipping with window shifted
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Graphics Architectures

• Geometric Pipeline
• Transformation
• Objects are represented in terms of the
  coordinate system of display
• Clipping
• No imaging system can see the whole world at once
• Projection
• The geometry of 3D objects is projected into 2D
  objects
• Rasterization
• Projected objects is represented as pixels in
  frame buffer