Computer Graphics Multiple choice Questions and Answers-Two Dimensional Viewing

61.	To set line width attributes in a PHIGS package, ................... function is used
a.	setLineWidthScaleFactor(lw)
b.	setLineThickness(lw)
c.	setPolylineWidth(lw)
d.	setLineWidth(lw)

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Answer: (a).setLineWidthScaleFactor(lw)

62.	The process of extracting a portion of a database or a picture inside or outside a specified region are called
a.	Transformation
b.	Projection
c.	Clipping
d.	Mapping

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Answer: (c).Clipping

63.	The rectangle portion of the interface window that defines where the image will actually appear are called
a.	View port
b.	Transformation viewing
c.	Clipping window
d.	Screen coordinate system

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Answer: (a).View port

64.	Coordinates of window are knows as ..............
a.	Screen coordinates
b.	World coordinates
c.	Device coordinates
d.	Cartesian coordinates

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Answer: (b).World coordinates

65.	Coordinates of viewport are known as ............
a.	World coordinates
b.	Polar coordinates
c.	Screen coordinates
d.	Cartesian coordinates

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Answer: (c).Screen coordinates

66.	The region against which an object is clipped is called a ..............
a.	Clip window
b.	Boundary
c.	Enclosing rectangle
d.	Clip square

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Answer: (a).Clip window

67.	............. identifies the picture portions that are exterior to the clip window
a.	Interior clipping
b.	Exterior clipping
c.	Extraction
d.	None of the above

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Answer: (b).Exterior clipping

68.	Identify line clipping algorithms from the following
a.	Cohen- Sutherland algorithm
b.	Liang-Barsky clipping
c.	Nicholl-Lee-Nicholl clipping
d.	All of the above

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Answer: (d).All of the above

69.	The region code of a point within the window is ............
a.	0000
b.	0001
c.	1000
d.	1111

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Answer: (a).0000

70.	According to Cohen-Sutherland algorithm, a line is completely outside the window if ............
a.	The region codes of line endpoints have a '1' in same bit position.
b.	The endpoints region code are nonzero values
c.	If L bit and R bit are nonzero.
d.	The region codes of line endpoints have a '0' in same bit position.

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Answer: (a).The region codes of line endpoints have a '1' in same bit position.