Computer Graphics Questions and Answers Part-30

1. In cabinet projection, what is the projected length of the lines that are perpendicular to the viewing plane?
a) Same length as the original
b) Double the length of the original
c) Half the length of the original
d) Projected length does not depend on the original length

Answer: c
Explanation: In cabinet projection, the projected length of the lines that are perpendicular to the viewing plane is half the length of the original. It gives a more realistic view of the object than the cavalier projection.

2. In which of the following projection, the object size differs when look from different distances?
a) Parallel Projection
b) Cavalier Projection
c) Perspective projection
d) Cabinet Projection

Answer: c
Explanation: In perspective projection, the size of the image differs when look from different distances. This happens due to the size of image is inversely proportional to the distance between the projection plane and the centre of projection.

3. What is the distance of centre of projection from the projection plane in perspective projection?
a) There is an infinite distance
b) There is a finite distance
c) Point of projection lies on the projection plane itself
d) Distance between centre of projection and projection plane cannot be told

Answer: b
Explanation: In Perspective Projection the centre of projection is at finite distance from projection plane. This projection produces realistic views but does not preserve relative proportions of an object dimensions.

4. Perspective projection can be divided into how many categories?
a) 3
b) 4
c) 5
d) 6

Answer: a
Explanation: Perspective projection can be divided into three parts. These are One-point perspective, Two-point perspective and Three-point perspective.

5. In perspective projection, what happens to the size of the image when the object moves far from the projection plane?
a) There is no change in size of image
b) Size of image gets bigger
c) Size of image gets smaller
d) There is no image in perspective projection

Answer: c
Explanation: In perspective projection, images of distant object are smaller than images of objects of same size that are closer to projection plane. More we increase the distance from the centre of projection, smaller will be the object appear.

6. In perspective projection, which of the following is the point where all lines will appear to meet?
a) Projectors
b) Projection Plane
c) Point of Projection
d) Vanishing Point

Answer: d
Explanation: In Perspective projection, Vanishing point is the point where all lines appear to meet at some point in the view plane. Classification of perspective projection is on basis of vanishing points, vanishing point is a point where projection line intersects view plane.

7. Which of the following type of perspective projection is used in drawings of railway lines?
a) One-point
b) Two-point
c) Three-point
d) Perspective projection is not used to draw railway lines

Answer: a
Explanation: The One Point projection is mostly used to draw the images of roads, railway tracks, and buildings. A One Point perspective contains only one vanishing point on the horizon line which helps in the making of railway tracks.

8. Which of the following type of perspective projection is also called as “Angular Perspective”?
a) One-point
b) Two-point
c) Three-point
d) Four-Point

Answer: b
Explanation: Two Point is also called “Angular Perspective.” A Two Point perspective contains two vanishing points on the line, the two points make a angle in between them which is why it is also called as angular perspective.

9. In perspective projection, at which of the following point the eyes of the observer are located?
a) Vanishing Point
b) Perspective Point
c) Observer Point
d) Station Point

Answer: d
Explanation: A station point is the location from which an artist intends the observer to view an artwork or picture. It is where the eyes of the observer are located. In photography, the station point is the location of the camera when it captures a picture.

10. How many axis intersects with the projection plane in the three-point perspective projection?
a) One
b) Two
c) Three
d) No axis intersects the projection plane

Answer: c
Explanation: In three point perspective projection, three axis intersects with the projection plane. This type of projection has 3 different vanishing points. Every axis intersects the projection plane and none of the axis is parallel to the plane.