Introduction to Computer Graphics

Defining Computer Graphics

• Computer graphics are any sketch or drawing that represents meaningful information.
• Computer graphics create or manipulate images using pixels on a computer.
• The graphics area is the part of an application where users create and modify drawings.
• Examples of types of computer graphics include raster and vector graphics:
  • Raster Graphics: Uses pixels to create an image (also known as a bitmap image).
  • Vector Graphics: Uses mathematical formulas to define shapes, lines, and objects.

Comparing Raster and Vector Graphics

• Raster graphics are made up of pixels.
• Vector graphics use mathematical formulas to define shapes.
• Raster graphics are good for photographs and realistic images.
• Vector graphics are good for illustrations, logos, and designs.

Applications of Computer Graphics

• Education and Training: Computer graphics are used to visualize complex concepts, creating educational aids and training simulations.
  • Examples: Flight simulators, models of physical and economic systems, population trends.
• Biology: Molecular biologists use computer graphics to visualize molecules and understand their structure.
• Maps: Town planners and transportation engineers use computer-generated maps to visualize data and make informed decisions.
• Architecture: Architects use computer graphics to explore design solutions and test various ideas.
• Presentations : Presentation graphics are used to summarize information with visual elements like bar charts, line graphs, and pie charts.
• Art: Computer graphics are used to create commercial art, including television and advertising commercials, as well as fine art.
• Entertainment: Computer graphics are used to create motion pictures, music videos, and television shows.

Computer Graphics Systems

• Input Devices: Tools used to interact with the system. Examples include:
  • Physical: Keyboard, mouse, tablet, touchscreen, camera.
  • Logical: String, locator, pick, choice, valuator, stroke.
• Output Devices: How the computer presents information to the user. Examples include:
  • CRT display, LED display, LCD display, printer, plotter, speaker, robot arm.
  • 2-D Output: Either vector devices (draw line segments, like a plotter) or raster devices (display pixels).

Graphics Primitives

• Graphics Primitive: A basic building block used to create complex images. Examples include:
  • Pixel: A single point of light on a raster display.
  • Line: A straight line segment, a fundamental element in creating images.
  • Polygon: A closed area bounded by straight or curved lines, used for creating shapes and objects.
  • Display File: A set of uncorrelated data forming an image.
  • Frame Buffer: Memory that stores a complete set of image data, displayed to the screen.
  • Display Control: Allows viewing images from different angles and magnifications.
  • Line Generation: Algorithms used to create lines on a screen.
  • Graphics Software: Programs designed to manipulate visual images on a computer.
  • Points: Used as building blocks for more complex shapes.
  • Polygons: Used to create 3D-looking images.
  • Text Primitive: Allows adding text to images at any position in 2-D or 3-D space.
  • Windowing and Clipping: Controls what part of an image is visible on the screen.
  • Viewport: A rectangular viewing region on a display.

Graphic Communication

• Graphic communication encompasses the creative and production process for any visual communication. This can include mediums such as billboards, magazines, websites, and videos.

Major Applications of Computer Graphics

• Computer Art: Used to create fine art and commercial art with animation packages and paint programs. Examples include cartoon drawing, painting, and logo design.
• Computer Aided Drawing: Used in designing buildings, automobiles, and aircraft, providing detailed and accurate drawings.
• Education: Computer-generated models are used to teach concepts in an engaging and accessible way.
• Training: Specialized systems like simulators are created to train individuals in specific skills.
• Visualization: Used to visualize complex data and processes, helping to gain insights and understand information.
  • Examples: Data visualization for business analysis, scientific research, and medical imaging.
• Image Processing: Used to edit and refine images, improving their clarity and usability.
• Machine Drawing: Used in designing and creating machine parts, ensuring precision and clarity for safe manufacturing.
• Graphical User Interface: Used to create user-friendly interface designs with pictures, icons, menus, and graphical objects.
• Additional Applications:
  • Entertainment: Used in movies, video games, and television shows.
  • Medical Imaging: Generates scans like body and brain scans.
  • Graphical Interface: Creates automated environments.