1. Interaction & Visualisation
A 12-week Module
Eur Ing Dr Peter Nicholl
School of Computing & Mathematical Sciences

2. 1/2 - 2
Contact Details
• E-mail
p.nicholl@ulst.ac.uk
• Office
16E08
• Telephone
From outside: 028 9036 8910 (Internally: 8910)
Mobile: 07967144854 or #6500
• Secretary
Miss Sharon Kelly, 16J19

3. 1/2 - 3
Course Texts
• Required reading
– Computer Graphics (2nd edition), D. Hearn &
M.P. Baker, pub. Prentice-Hall, 1994/7
(ISBN 0-13-161530-0)
• Recommended reading
– Introduction to Computer Graphics, Foley, Van
Dam, et. al., pub. Addison-Wesley, 1994
– 3D Computer Graphics, A. Watt, pub.
Addison-Wesley, 1994

4. 1/2 - 4
Module Content
• Introduction to Computer Graphics
– Historical perspective
– Application areas
– Graphics standards
– Graphics software

5. 1/2 - 5
Module Content
• Introduction to Computer Graphics
• Hardware & Software Support
– Raster versus vector graphics
– Picture encoding techniques
– Display devices and hard copy

6. 1/2 - 6
Module Content
• Introduction to Computer Graphics
• Hardware & Software Support
• Clipping in 2 Dimensions
– Lines and polygons
– Windows and simple transformations
– Co-ordinate systems
– Reflections, shears and composition

7. 1/2 - 7
Module Content
• Introduction to Computer Graphics
• Hardware & Software Support
• Clipping in 2 Dimensions
• Scan Conversion
– Line drawing algorithms
– Circle generating algorithms
– Scan conversion of polygons
– Aliasing and anti-aliasing methods

8. Lectures One & Two
Introduction to Computer Graphics
& An Historical Perspective

9. 1/2 - 9
Application Areas: CAD
• Computer-Aided Design
– buildings, automobiles, aircraft, textiles,
computers, spacecraft, watercraft
– allows ‘what if’ investigation
– designs can be animated
– can be incorporated into virtual reality systems
– final appearance - shading, lighting, in-situ
– feed into computer-aided manufacture (CAM)

10. 1/2 - 10
Application Areas: Presentations
• Presentation graphics
– illustrations for reports
– summarise data
– production of 35mm slides and transparencies
– project management, e.g. time charts

11. 1/2 - 11
Application Areas: Art
• Computer Art
– paintbrush software
– modelling
– texture mapping
– mathematical art, e.g. fractals
– desktop publishing (DTP)
– logo design

12. 1/2 - 12
Application Areas:
Entertainment
• Motion pictures / music videos / TV shows
– graphics scenes by themselves
– graphics objects combined with actors
• Morphing
– transformation of one person / object into
another

13. 1/2 - 13
Application Areas: Education
• Education and Training
– Models of physical, financial and economic
systems
– Simulators

14. 1/2 - 14
Application Areas: Visualisation
• Aids analysis of large amounts of data
– colour coding, contour plots, surface rendering
– examples: airflow over a wing, minimal surface
functions
• Aids the study of the behaviour of certain
processes
– example: animation of the growth of a corn ear

15. 1/2 - 15
Related Disciplines
• Image Processing
– the application of techniques to modify or
interpret existing pictures
– computer graphics is the use of a computer to
create a picture
– both disciplines are often combined in many
applications, e.g. computer-aided surgery

16. 1/2 - 16
Related Disciplines
• Human-Computer Interaction
– graphical interfaces are now very common
– WIMP concept
• Window manager
• Icons to represent processing options
• Menus are textual descriptions of options
• Pointers, e.g. mouse, are used for selection

17. 1/2 - 17
An Historical Perspective
• Display of data on plotters and CRTs
– first simple pictures generated in 1950
(MIT’s Whirlwind I computer)
– slow progress over the 1950s (batch systems)
• Interactive computer graphics
– Sutherland’s Ph.D. thesis (1962) - Sketchpad
• Large research projects (The Golden Age)
– General Motors, Lockheed Aircraft, MIT

18. 1/2 - 18
An Historical Perspective
• Research bears fruit in the 1970s
– still a small, specialized field
– hardware expensive, software difficult to use
• The advent of the Personal Computer (’80s)
– built-in raster graphics displays
– mass-produced, less expensive
• The desktop concept

19. 1/2 - 19
Graphics Standards
• Aim: application-program portability
– isolate the programmer from the real devices
– also results in “Programmer portability”
• CORE Standard (1977 & 1979)
• Graphical Kernel System (1985) - GKS
• 3D-GKS (1988)
• Programmer’s Hierarchical Interactive
Graphics System (1988) - PHIGS