UNIVERSITY EXAMINATIONS: 2020/2021
EXAMINATION FOR THE DEGREES OF BACHELOR OF SCIENCE IN
INFORMATION TECHNOLOGY/ APPLIED COMPUTING
BIT 2301A/ BAC 3210: COMPUTER GRAPHICS
FULLTIME/ PART TIME/DISTANCE LEARNING
ORDINARY EXAMINATIONS
DATE: DECEMBER, 2021 TIME: 2 HOURS
INSTRUCTIONS: Question ONE IS COMPULSORY, Choose TWO OTHER Questions
QUESTION ONE (20 marks) Compulsory
a) The architecture of a raster-graphics system is partly made up of the components listed
below. Briefly explain the function of the following components and terms as used in image
formation and display in the display device. (10 Marks)
i). Display processor
ii). Frame Buffer
iii). Scan Conversion
iv). Video Controller
v). Display Processor Memory
b) Describe how to represent three different 2D transformations as matrices. (5 Marks)
c) Explain how to derive a sequence of transformations to achieve the overall effect of
performing a 2D rotation about an arbitrary point. (5 Marks)
QUESTION TW0 (15 marks)
a). Why are matrix representations used to describe point transformations in computer
graphics? (5 Marks)
b). Using Bresenham’s algorithm, determine the pixel location approximating the first octant of
a circle having centre at (4, 5) and radius 4. [6 Marks]
c). Briefly describe homogeneous coordinates and affine transformation as applied in computer
graphics. [4 Marks]
QESTION THREE (15 marks)
a). Distinguish between rasterization and scan conversion as applies to computer graphics.
[4 Marks]
b). “Graphics hardware can be divided into three major categories of devices”. Do you agree
with this statement? Explain in support of your answer. [4 Marks]
c). Explain how the interactive graphics display works. [ 3 Marks]
d). Name and explain the two basic methods used in generation of characters on a computer
screen. [4 Marks]
QUESTION FOUR (15 marks)
Using the DDA algorithm, find the intermediate points that can be drawn between the following
sets of points:
a). (3, 5) and (14, 15) [5 Marks]
b). (4, 3) and (9, 12) [5 Marks]
c). (5, 9) and (14, 16) [5 Marks]
