UNIVERSITY EXAMINATIONS: 2010/2011
SECOND YEAR EXAMINATION FOR THE DEGREE OF BACHELOR OF
SCIENCE IN INFORMATION TECHNOLOGY
BIT 2304: COMPUTER GRAPHICS
DATE: AUGUST 2011 TIME: 2 HOURS
INSTRUCTIONS: Answer question ONE and any other TWO questions
Question One (30 Marks)
a) Explain the concept of computer graphics. (4 Marks)
b) What is OpenGL? Write OpenGL commands that can used to generate a POINT, LINE and
POLYGON structures. (6 Marks)
c) Briefly distinguish between the following study domains and for each show how it relates to
computer graphics:
i. Pattern Recognition
ii. Computer Vision
iii. Image Processing
iv. Information Visualization (10 Marks)
d) Using concrete examples, explain how computer graphics can be used in each of the following
application areas.
i. Engineering
ii. Archeology
iii. Life sciences
iv. Business computing (10 Marks)
Question Two (20 Marks)
a) Define the terms: “Computer animation”, “Keyframe” and “In-between frame”. (6 Marks)
b) Describe three ways that animation in computer graphics can be developed. (8 Marks)
c) If you had to make a commercial tomorrow that included a running human, how would you capture
the motion of the human? (6 Marks)
Question Three (20 Marks)
a) Consider two raster systems with the resolutions of 640 x 480 and 1280 x 1024.
i. How many pixels could be accessed per second in each of these systems by a display
controller that refreshes the screen at a rate of 60 frames per second? (6 Marks)
ii. What is the access time per pixel in each system? (2 Marks)
b) Consider a raster system with the resolution of 1024 x 768 pixels and the color palette calls for
65,536 colors. What is the minimum amount of video RAM that the computer must have to support
the above-mentioned resolution and number of colors? (12 Marks)
Question Four (20 Marks)
Often, we display functions of the form y = f(x,z) by displaying rectangular mesh generated by the set
of values {f(xi,zj)} evaluated at regular intervals in x and z. Hidden-surface removal should be applied
because parts of the surface can be obscured from view by other parts.
Derive two algorithms, one using hidden-surface removal and the other using hidden-line removal, to
display such a mesh. (20 Marks)
Question Five (20 Marks)
a) Describe the basic principles in the ray tracing approach to producing computer Generated images.
(6 Marks)
b) Describe the specular and diffuse types of reflection in computer graphics. (6 Marks)
c) Discuss the Lambertian diffuse reflection model, and explain how it can be used for simple lighting
effects in polygonal and/or ray tracing. (8 Marks)
