Assignment
1. Write a general function for Rasterization.
2. Explain the role of pixel and frame buffer in graphics devices.
3. How much time is spent scanning across each row of pixels during screen refresh on a raster
system with resolution of 1280x1024 and a refresh rate of 60 frames per second?
4. Consider two raster systems with resolutions of 640x480 and 1280x1024. How much 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?
5. Explain how to display file structure and control test.
6. Compare the computation done in Digital Differential Analyzer (DDA) algorithm with
Bresenham’s line drawing algorithm.
Or
Compare digital differential analyzer with Bresenham’s line drawing algorithm.
7. Explain Bresenham’s algorithm for line drawing.
Or
Write integer Bresenham’s algorithm and show how it draws a line whose end point is (4,4
and start point is (-3,0).
8. Explain DDA with suitable example.
9. What are raster scan displays? Explain generating a raster image.
10. What do you understand by the term “corruption of display files”? Discuss how to avoid it.
11. Draw and explain the architecture of a raster graphics system with a display processor.
12. Determine the resolution (pixel per centimeter) in the x and y directions for the video
monitor in use on your system. Determine the aspect ratio, and explain how relative
proportions of object can be maintained on your system.
13. Explain vector generation.
Or
Discuss the criteria that should be satisfied by a good line drawing algorithm to have
computer generated line.
14. What are logical interactive devices? Explain some of the logical functions with examples.
15. List and explain the principles behind the working of output devices.
16. Describe the construction and functioning of Beam Penetration CRT. Discuss its merits and
demerits.
17. What do you understand by the terms interlaced and non-interlaced scans?
18. How can weighted and unweighted sampling be used to remove aliasing effects.
19. For the points P1(1,1), P2(4,5) and P3(6,2), find the distance between P1 and line passing
through P2 and P3.
20. Attempt any four Questions.
a. Describe the construction and functioning of Beam Penetration CRT. Discuss its
merits and demerits.
b. What do you understand by the terms Interlaced Non-interlaced scans?
c. Consider two raster systems with resolution of 640 x 480 and 1280 x 1024. 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?
d. Is Rotation concatenation additive? If yes, justify.
e. What is Shear transformation? Explain it in detail.
f. Explain the role of pixel and frame buffer in graphics devices.
21. Attempt any two Questions.
a. Discuss the criteria that should be satisfied by a good line drawing algorithm to have
computer generated lines.
b. Describe Mid-point Method for Circle generation in detail.
c. Write integer Bresenham Algorithm and show how it draws a line whose end-point is
(4, 4) and start-point is (-3, 0).
22. Attempt any two Questions.
a. What do you understand by the term “Concatenation of Transformations”? What are
its advantages? If A and B are two different transformations, illustrate with suitable
example that A.B  B.A .
b. What are homogeneous coordinates? If a line whose end-points are
 x2 , y2 
 x1, y1 
and
exists in 2 D space, then write the concatenation of matrices that will rotate
the mirror image of the line about mid-point of the line by an angle 60 counterclockwise. Each of the transformations has to be in homogeneous coordinate system.
c. Write procedure for rotation and translation transformation. Derive reflection
matrices for reflection about the x-axis.
23. Define.
a. Vanishing points.
b. Center of Projection.
d.
Window
e.
Viewport
c. Windowing & clipping
24. Explain Viewing pipeline in detail.
25. What is window-to-viewport point coordinate transformation?
26. Explain Axonometric projection and Oblique projection.
27. Explain 3 D clipping.
28. Explain Text Clipping.
29. A cube is placed at the origin of 3 D system. Such that all its vertices have positive
coordinate values and sides are parallel to the three principal axes. Indicate a convenient
position of a viewer at which he can see a 2-point perspective projection. Verify that such a
view is generated.
30. Show that the perspective projection matrix
P=
-ZC
0
0
0
1
0
0
0
0
-ZC
0
0
0
1
0
0
XC
YC
0
1
-XC / ZC
-YC / ZC
0
-1 / ZC
0
0
0
-ZC
0
0
0
1
is equivalent to
31. Derive 3 D homogeneous transformation matrix for rotating a point (x, y, z) by π/4 about the
x-axis (y into z).
32. Write the steps for clipping the polygon given in figure using the Sutherland-Hodgman
polygon clipping algorithm.
B
A
C
D
33. Use the Liang-Barsky line clipping algorithm to clip the line P1 (-15, -30) – P2 (30, 60)
against the window having diagonally opposite corners as (0, 0) and (15, 15).
34. Find the normalization transformation for window to viewport which uses the rectangle
whose lower left corner (2, 2) and upper right corner (6, 10) as a window and the viewport
that has lower left corner at (0, 0) and upper right corner at (1, 1).
35. A clipping window PQRS has left corner at (3, 4) and upper right corner at (10, 9). Find the
section of the clipped line AB, CD and EF using the Cohen-Sutherland line clipping
algorithm.
A (2, 11)
E (7, 11)
D (4, 6)
F (11, 7)
C (1, 4)
B (9, 2)
36. Derive the transformation matrix for rotating any object by 45º about an axis passing through the
origin and point (10, 0, 10).
37. Demonstrate local scaling taking scaling factors along the x, y and z axes as 2, 3, and 1
respectively, for a cube with homogeneous position vectors. Next reflect the resultant about
xy plane.