Computer Graphics Questions and Answers Part-6

1. The algorithm which displays line-type attributes by plotting pixel spans is
a) Raster line algorithm
b) Raster scan algorithm
c) Random line algorithm
d) Random scan algorithm

Answer: a
Explanation: Raster line algorithm displays line-type attributes.

2. Pixel mask means
a) A string containing only 1's
b) A string containing only 0’s
c) A string containing 1 and 0
d) A string containing 0 and 0

Answer: c
Explanation: Inter span spacing can be specified in a pixel mask that contains digits 1 and 0.

3. A heavy line on a video monitor could be displayed as
a) Adjacent perpendicular lines
b) Adjacent parallel lines
c) Both a and b
d) Neither a nor b

Answer: b
Explanation: A heavy line displayed as adjacent parallel lines, while pen plotter might require pen changes.

4. To set the line-width attribute the following command is used.
a) SETLINEWIDTHSCALEFACTOR (lw)
b) Setlinewidth()
c) Setlinewidthscalefacto (lw)
d) setLineWidthScaleFactor (lw)

Answer: d
Explanation: setLineWidthScaleFactor (lw) function can be used to set line-width attribute.

5. The parameter to “setLineWidthScaleFactor (lw) “function specifies?
a) Standard width
b) Relative width of the line
c) Thickness of the line
d) All of the mentioned

Answer: b
Explanation: The positive value to lw indicates the relative width of the line.
Standard width, if Value=1
Thickness, if value>1.

6. We can adjust the shape of the line ends to give them a better appearance by using
a) Line spacing
b) More dots
c) Line caps
d) Round cap

Answer: c
Explanation: Line caps are obtained by adjusting the end points of the line.

7. Thick line drawn with
a) Butt caps
b) Round caps
c) Projecting square caps
d) All of the mentioned

Answer: d
Explanation: All of the mentioned

8. We set the line-color value in PHIGS with the function
a) setPolylineColorIndex (lc)
b) setline Color()
c) SETPOLYLINECOLORINDEX (lc)
d) Only b

Answer: a
Explanation: The setPolylineColorIndex (lc) function is used to set the line color.

9. If the angle between 2 connected line segments is very small then ________ can generate a long spike that distorts the appearance of the polyline.
a) Miter join
b) Round join
c) Bevel join
d) None of the mentioned

Answer: a
Explanation: Miter join provides long spikes that distort the appearance of the polyline.

10. A line drawn in the background color is
a) Visible
b) Invisible
c) Visible or Invisible
d) None of the above

Answer: b
Explanation: A line drawn in the background color is always invisible because both are same color.