DipIETE – CS (OLD SCHEME)
Code: DC09 Subject:
COMPUTER GRAPHICS
Time: 3 Hours Max. Marks: 100
NOTE: There are 9 Questions in all.
· Question 1 is compulsory
and carries 20 marks. Answer to Q.1 must be written in the space provided for
it in the answer book supplied and nowhere else.
· Out of the remaining
EIGHT Questions, answer any FIVE Questions. Each question carries 16 marks.
· Any required data not
explicitly given, may be suitably assumed and stated.
Q.1 Choose the correct or the best alternative in the following: (2
10)
a.
DDA
algorithm used to _________.
(A) draw a rectangle (B) draw a circle
(C) draw a polygon (D)
draw a line
b. Which display device is best suited for CAD system?
(A)
A
CRT with vector refresh monitor.
(B)
A
CRT with raster scan monitor.
(C) Plasma panel display.
(D) LED display.
c. In the mid point subdivision method of clipping, the maximum number of subdivision required, if the maximum number of pixels in a line is M, is ________.
(A)
(B)
(C) C =
2M (D)
None of the above
d. Oblique projection with an angle of 
to the horizontal
plane is called ________.
(A)
cabinet (B) isometric projection
(C) cavalier projection (D)
None of the above
e. Which projection shortens two axis equally?
(A)
Trimetric
projection. (B) Parametric
projection.
(C) Diametric projection. (D) None
of the above.
f. When the scaling factor is S < 1 then after scaling there will be _________.
(A)
increase
in size (B) reduction in size
(C) rotation (D) reflection
g. Assuming that one is allowed to use 256 depth
values levels, how much memory would a 
pixel display require to the z-buffer?
(A)
512
K. (B)
256 K.
(C) 1024 K. (D)
128 K.
h. A Bezier cubic curve with control points 
is defined by the equation
than 
is equal to
(A)
. (B)
.
(C) 
. (D)
i. The portion of memory used to hold pixels is called __________.
(A) Pitch (B) Frame Buffer
(C) RAM (D) ROM
j. The RGB co-ordinate of a color at (0.15, 0.75, 0) in the CMY space is ___________.
(A) (0.85, 0.25, 1) (B) (0.75, 0.15, 1)
(C) (0.25, 1, 0.65) (D)
(0.85, 0.35, 0)
Answer
any FIVE Questions out of EIGHT Questions.
Each
question carries 16 marks.
Q.2 a. How computer graphics is used for simulation,
animation and video games? (6)
b. Explain
the focusing, deflection hardware and working of CRT. (10)
Q.3 a. Explain the following Input Devices: (9)
(i) Light Pen.
(ii) Optical Touch Panels.
(iii) Digitizing
Tablets.
b. Scale
the triangle with vertices A(0, 0), B(2, 2) and C(5, 3) three times of its size
while keeping C(5, 3) fixed. (7)
Q.4 a. Describe briefly zooming and panning. (4)
b. Draw a flowchart for Bresenham’s incremental circle algorithm in
first quadrant and then write the pseudocode. (8)
c. What are the properties of Bezier curves? (4)
Q.5 a. Describe
midpoint subdivision clipping algorithm. (8)
b. Explain scan line seed fill algorithm. (8)
Q.6 a. Write
steps to generate a bar chart. (4)
b. A pyramid defined by the coordinates A(0, 0,
0), B(1, 0, 0), C(0, 1, 0) and D(0, 0, 1) is rotated by
about the line L that
has the direction V = J +K and passing through the point C(0, 1, 0) Fig. 1. Find the coordinates of the rotated figure.
(8)
c. What
is the principal vanishing point? Describe the one vanishing-point perspective
projection. (4)
Q.7 a. Explain z-buffer algorithm. What are the advantages and disadvantages of
z-buffer algorithm? (8)
b. Derive the equation of parallel projection on the xy plane in the
direction of projection vector V = aI + bJ + cK. (5)
c. What do you mean by oblique parallel
projection? (3)
Q.8 a. Explain sweep representation and constructive
solid geometry methods for solid modelling. (8)
b. The
term R.V in the phong formula is sometimes replaced by N.H, where H is a unit
vector that bisects the angle between L and V.
Show that R.V 
N.H. (5)
c.
Define Lambert’s cosine law in context of diffuse
reflection. (3)
Q.9 a. Explain the concept of Hypertext and
Hypermedia. (4)
b. What are the advantages of
c. Write short note on the following:
(i) Video conferencing.
(ii) Windows paintbrush. (42)