Quiznetik

Computer Graphics | Set 1

1. An -------------test is used to check whether a point is inside or outside of the polygon.

Correct : A. inside

2. In an inside test if number of intersections are ---------------- then point is inside of the polygon. Note : intersection point is not a vertex.

Correct : B. odd

3. In an inside test if number of intersections is odd then point is ---------------- of the polygon. Note : intersection point is not a vertex

Correct : A. inside

4. In an inside test if intersections point is a vertex and edges meeting at that vertex lies on same side of constructed horizontal line then the number of intersections are considered as ----------. Note : intersection point is a vertex

Correct : A. even number

5. In an inside test if intersections point is a vertex and edges meeting at that vertex lies on ------------- side of constructed horizontal line then the number of intersections are considered as even number . Note : intersection point is a vertex

Correct : A. same

6. Two inside polygon test methods are __________ and ________

Correct : A. even odd method , winding number method

7. The 8-Fill Polygon technique will correctly fill the triangle shown below when seeded at the position shown with an X.

Correct : B. false

8. Following is the method for inside test of the polygon.

Correct : A. even-odd method

9. Every side in winding number method has given a number called

Correct : A. winding number

10. The total of the winding no. in winding number method of inside test is called as

Correct : C. net winding.

11. Winding number method always gives correct answer for overlapping polygons

Correct : B. false

12. Inside tests of polygon are useful in --------

Correct : A. polygon filling

13. Even-odd method of inside test counts ----- to decide the position of a point.

Correct : C. intersections

14. In winding number method an ------------------ edges ------ considered

Correct : A. horizontal , not

15. Even-odd method of inside test is suitable for------

Correct : A. polygons

16. In winding number method an edge can have winding number as -----

Correct : B. +1 or -1

17. If the pixel is already filled with desired color then does nothing, otherwise fills it. This is called

Correct : B. boundary fill algorithm

18. The algorithm used for filling the interior of a polygon is called

Correct : A. flood fill algorithm

19. ___________ procedure accepts the coordinates of an internal point.

Correct : B. boundary fill.

20. In 8 connected region by knowing one pixel we can get remaining ---------------- neighboring pixels.

Correct : A. 8

21. Following statement(s) is/are true about flood fill algorithm

Correct : D. all of above

22. Following statement(s) is/are false about flood fill algorithm

Correct : A. it doesn’t need a seed pixel

23. Seed pixel in flood fill Algorithm is an

Correct : A. an interior pixel

24. In Boundary Fill method ____________ Data Structure is used.

Correct : A. stack

25. The 4-connected Polygon filling technique has disadvantage(s) as

Correct : D. all of above

26. In --------------algorithm edges can be specified in different color.

Correct : A. flood fill

27. The process of coloring the area of a polygon is called

Correct : A. polygon filling

28. Boundary fill algorithm uses -------- call to the fill function.

Correct : A. recursive

29. Boundary fill algorithm needs–

Correct : C. boundary color (bc), fill color (fc) and (x,y) coordinates of seed point.

30. Which polygon fill algorithm needs following information - 1.Boundary Color (BC), 2. Fill Color (FC) and 3. (x,y) coordinates of seed point.

Correct : A. boundary fill

31. Which polygon fill algorithm needs following information - 1. Region Color (RC), 2. Fill Color (FC) and 3. (x,y) coordinates of seed point.

Correct : A. flood fill

32. Horizontal lines are not considered in scan line fill algorithm.

Correct : A. true

33. Scan line fill algorithm is more efficient than flood fill algorithm.

Correct : A. true

34. Which statement is true about the 4 connected region.

Correct : C. both a and b

35. The function of scan line polygon fill algorithm are :

Correct : A. find intersection point of the boundary of polygon and scan line

36. The edge table contains pointers back to the ______________ to identify vertices for each polygon edge.

Correct : A. vertex table.

37. Scan line polygon filling method uses

Correct : D. both a and b

38. Scan-line coherence property is used in

Correct : B. scan line polygon filling algorithm

39. Which of the following is true about scan line algorithm?

Correct : C. it uses scan lines to fill the polygon

40. In scan line algorithm the intersection points are

Correct : A. sorted in ascending order

41. Which of the following algorithms to fill polygons was the one used by real rasterizers?

Correct : B. scan-line polygon

42. Active edge table is used in following algorithm

Correct : C. scan line

43. Scan line polygon filling algorithm uses series of ……………. To fill the polygon.

Correct : A. scan lines

44. In scan line algorithm, Scan lines are processed in increasing (upward) / decreasing (downward) --------------------------.

Correct : A. y order

45. When the current scan line in Scan line polygon fill algorithm moves above the upper / below the lower endpoint, the edge

Correct : A. becomes inactive

46. The edges crossed by current scan line in Scan line polygon fill algorithm are called as

Correct : A. active edges

47. Scan line Fill Approach works at the

Correct : C. polygon level

48. Following are the data structures used in Scan line algorithm to increase the efficiency.

Correct : C. both a and b

49. Scan line polygon filling algorithm starts from

Correct : A. either ymax or ymin

50. Scan line polygon filling algorithm can be used for filling Convex polygon.

Correct : A. true

51. Using Cohen-Sutherland line clipping, it is impossible for a vertex to be labeled 1111

Correct : A. true

52. Which one is not valid out code to perform trivial accept / reject test in line clipping

Correct : A. 1101

53. Why the Cohen-Sutherland Line-Clipping Algorithm involves much more calculations than the other line clipping algorithms?

Correct : B. need to perform trivial accept / reject test for every point on the line.

54. If the x coordinate boundaries of the clipping rectangle are Xmin and Xmax, and the y coordinate boundaries are Ymin and Ymax, then ___________ must be satisfied for a point at (X,Y) to be inside the clipping rectangle

Correct : C. xmin < x < xmax and ymin < y < ymax

55. determine whether points (P1, P2 and P3) are clipped away or visible after clipping by applying the rules

Correct : D. p1: clipped away, p2:visible, p3:clipped away

56. Outcode / Region Code used in Line Clipping is of size ____ bits.

Correct : A. 4

57. In Line Clipping algorithm, the two dimensional space is divided into ___ regions.

Correct : C. 9

58. Is 0011 valid region code / outcode used in Line Clipping algorithm?

Correct : B. no

59. Cohen – Sutherland line clipping algorithm was developed in ____

Correct : A. 1967

60. Primitive types of clipping algorithms are

Correct : D. all of above

61. In ________ operation eliminates objects or portions of objects that are not visible through the window to ensure the proper construction of corresponding image

Correct : A. clipping

62. The region against which an object is clipped is called as ____________

Correct : A. clip window

63. Cohen – Sutherland Line Clipping Algorithm is also called as ____________________

Correct : B. cohen - sutherland outcode algorithm

64. Following are coordinates of clipping window : Lower Left Corner (20,20) and Upper Right Corner (200,200). What is the outcode of point (150,50)?

Correct : C. 0

65. The selection and separation of a part of text or image for further operation are called

Correct : D. clipping

66. The complex graphics operations are

Correct : B. clipping

67. The process of extracting a portion of a database or a picture inside or outside a specified region are called

Correct : D. clipping

68. The rectangle space in which the world definition of region is displayed are called

Correct : B. clipping window or world window

69. ............. identifies the picture portions that are exterior to the clip window

Correct : B. exterior clipping

70. The region code of a point within the window is ............

Correct : B. 0

71. According to Cohen-Sutherland algorithm, a line is completely outside the window if ............

Correct : A. the region codes of line endpoints have a \1\ in same bit position.

72. The region code of a point is 11. The point is in the ................. region of window.

Correct : A. top left

73. The result of logical AND operation with endpoint region codes is a nonzero value. Which of the following statement is true?

Correct : B. the line is completely outside the window

74. The left (L bit ) bit of the region code of a point (X,Y) is '1' if ......................

Correct : B. x< xwmin

75. The right bit (R bit)of the region code of a point (X,Y) is '1' if ......................

Correct : D. x>xwmax

76. The Most Significant Bit of the region code of a point (X,Y) is '1' if ......................

Correct : D. y>ywmax

77. The bottom bit of the region code of a point is '0' if .......................

Correct : D. y>ywmax

78. The ...................... algorithm divides a 2D space into 9 regions, of which only the middle part (viewport) is visible.

Correct : A. cohen-sutherland

79. Sutherland Hodgeman algorithm works well for...........

Correct : B. convex polygons

80. A line with endpoints codes as 0000 and 01 is ?

Correct : A. partially invisible

81. In a clipping algorithm of Cohen & Sutherland using region codes, a line is already clipped if the ?

Correct : D. only a

82. Sutherland – Hodgman algorithm is used for _______________.

Correct : B. polygon clipping

83. Which polygon clipping algorithm executed by clipping all polygon edges against the viewing screen edges one viewing screen edge at a time?

Correct : B. sutherland hodgman

84. In Sutherland – Hodgman algorithm for polygon clipping , assume P (present point ) lies inside the window and S ( Previous point) lies outside the window. Then while processing through that window boundary we should

Correct : B. store point p and s’

85. In Sutherland – Hodgman algorithm for polygon clipping , assume P (present point ) lies outside the window and S ( Previous point) lies outside the window. Then while processing through that window boundary we should

Correct : D. store nothing

86. In Sutherland – Hodgman algorithm for polygon clipping , assume P (present point ) lies outside the window and S ( Previous point) lies inside the window. Then while processing through that window boundary we should

Correct : A. store interaction point of line ps (s’) only

87. In Sutherland – Hodgman algorithm for polygon clipping , assume P (present point ) lies inside the window and S ( Previous point) lies inside the window. Then while processing through that window boundary we should

Correct : C. store point p only

88. In Sutherland – Hodgman algorithm for polygon clipping, clipping along boundaries sequence is used as

Correct : A. left -> right -> top -> bottom

89. Polygon-Clipping algorithms include the:

Correct : D. all of above

90. _______ is a ordered list of vertices where each vertex connected with the next in the list.

Correct : B. polygon

91. Types of polygon :

Correct : D. all of above

92. Concave and Convex are types of _______

Correct : C. polygon

93. In convex Polygon all interior angles are

Correct : B. less than 180

94. In concave Polygon atleast one interior angle is

Correct : C. greater than 180

95. A region S is ____ , iff for any x1 and x2 in S, the straight line segment connecting x1 and x2 is also contained in S.

Correct : B. convex

96. _____ may not always be Convex .

Correct : C. polygon

97. __________ is represented as a number of line segments connected end to end to form a closed figure.

Correct : C. polygon

98. ___________ is not a Type of polygon

Correct : C. linear

99. Right angled Triangle is an example of ____ Polygon

Correct : B. convex

100. Square is an example of ____ Polygon

Correct : A. convex