1. Which of the following co-ordinates are NOT used in 2d viewing transformation?
a) modelling co-ordinates
b) viewing co-ordinates
c) vector co-ordinates
d) device co-ordinates
Explanation: Vector co-ordinates are used to denote vectors which are physical quantities having magnitude as well as direction. In 2d viewing transformations- Modelling co-ordinates, viewing co-ordinates, Normalised co-ordinates and Device co-ordinates are used.
2. The process of elimination of parts of a scene outside a window or a viewport is called _____________
a) cutting
b) plucking
c) clipping
d) editing
Explanation: Clipping is the process of cutting out extra material. In the context of computer graphics, clipping is a method to selectively enable or disable rendering operations within a defined region of interest.
3. For a 2d transformation viewing, in how many ways a clipping algorithm can be applied?
a) 3
b) 2
c) 1
d) 5
Explanation: Clipping algorithm can be applied in two ways for 2d transformation viewing. Two ways in which clipping algorithms can be applied are- 1) world co-ordinate clipping. 2) viewport clipping.
4. Which of the following is NOT a type of clipping algorithm used on the raster system?
a) line clipping
b) point clipping
c) area clipping
d) solid clipping
Explanation: Since clipping is done in 2 dimensional viewing and solid is a 3 dimensional object so clipping algorithm can’t be applied on a solid object. Instead of solid clipping, there is another type of clipping algorithm known as curve clipping.
5. What is the primary use of clipping in computer graphics?
a) adding graphics
b) removing objects and lines
c) zooming
d) copying
Explanation: The primary use of clipping in computer graphics is to remove objects, lines, or line segments that are outside the viewing pane.
6. A polygon can be clipped using clipping operations.
a) True
b) False
Explanation: A polygon can also be clipped by specifying the clipping window. Sutherland Hodgeman polygon clipping algorithm is used for polygon clipping.
7. Which type of clipping is used to clip character strings?
a) text clipping
b) line clipping
c) sentence clipping
d) word clipping
Explanation: Text clipping is the algorithm which is used to clip character strings. It depends on the methods which are used to generate original characters.
8. In polygon clipping, line clipping algorithms can be used.
a) True
b) False
Explanation: Polygon is a two dimensional shape formed by straight lines. So we can conclude, polygon’s basic components are lines, hence line clipping algorithm can be used for polygon clipping.
9. Which vertex of the polygon is clipped first in polygon clipping?
a) top right
b) bottom right
c) bottom left
d) top left
Explanation: In polygon clipping, first the polygon is clipped against the left edge of the polygon window to get new vertices of the polygon. So, it is the top left which is clipped first.
10. How many methods of text clipping are there?
a) 5
b) 4
c) 3
d) 2
Explanation: There are three methods for text clipping which are −
1) All or none string clipping 2) All or none character clipping 3) Text clipping.