Computer Graphics Basics

What is it?

What is it good for?

• Understanding and interpreting information: Visualization is necessary for dealing with complex data.

• Improved communitcation with computers: Graphical and audio interfaces are helpful.

• Better product designs: Designers can explore more avenues in less time and can focus on the creative aspects of design (which do not include drafting).

• More economical designs: Design databases can be "tested" electronically, reducing dependence on complex and costly physical modes (e.g. aircraft).

• Better products:: Design databases can be transmitted to robots for manufacturing (3-D output).

Where is the technology used?

• User Interfaces

• Hypermedia

• Presentation Graphics

• Electronic Publication

• Office Automation

• Computer Aided Design

• Architecture
• Engineering (VLSI, complex machienery)

• Visualization

• Chemical Analyses
• Demographic Studies
• Financial Planning
• Cartography
• Particle Behavior
• Medical (ultrasound, CT, MRI, PET)
• Meteorological Studies
• Photograph Enhancement

• Education

• Tutorial Software

• Process Control

• Monitoring of power plants, computer networks, airplane traffic, tornados

• Entertainment

• Feature Films
• Animated Programs
• Virtual Reality
• Arcade, Console, PC Games

• Simulation

• Factory Simulation
• Flight Simulators

• Graphic Arts

• Video Painting, etc.

Subfields of Computer Graphics

It seems to me there are eight fundamental areas of computer graphics. Obviously this is debatable, but this classification seems to work.

1. Mathematical Structures

   Spaces, points, vectors; dusts, curves, surfaces, solids.

2. Modeling (Object Modeling)

   Description of objects and their attributes, including

   • Primitives (e.g. pixels, polygons)
   • Intrinsic Geometry
   • Attributes (e.g. color, texture)
   • Connectivity (e.g. scene graphs)
   • Dynamics (e.g. motion, morphing)

   Techniques for object modeling, including

   • polygon meshes
   • patches
   • solid geometry
   • sweeps
   • fractals
   • particle systems
   • L-grammars

3. User Interfaces

   Human factors, I/O devices, color theory, workstations, interactive techniques, dialog design, animation, metaphors for object manipulation, virtual reality.

4. Graphics Software

   Graphics APIs; paint, draw, CAD and animation software; modeling and image databases; iconic operating systems; software standards.

5. Graphics Hardware

   I/O devices, specialized chips, specialized architectures.

6. Viewing

   Abstract to device coordinate transformations, the syntehetic camera, windows, viewports, clipping.

7. Rendering

   Realism, physical modeling, ray tracing, radiosity, visible surface determination, transparency, translucency, reflection, refraction, shadows, shading, surface and texture mapping.

8. Image Processing

   Image description, image storage, image transformations, image filtering, image enhancement, pattern recognition, edge detection, object reconstruction.

Objects vs. Images

Objects are the (usually 3-D) conceptual entities that exist in their own coordinate systems; images are the (usually 2-D) realizations of objects on some media.

Current Trends

Example Code