1.The matrix representation for translation in homogeneous coordinates is
a) P’=T+P
b) P’=S*P
c) P’=R*P
d) P’=T*P
Answer
Answer: d [Reason:] The matrix representation for translation is P’=T*P.
2. The matrix representation for scaling in homogeneous coordinates is
a) P’=S*P
b) P’=R*P
c) P’=dx+dy
d) P’=S*S
Answer
Answer: a [Reason:] The matrix representation for scaling is P’=S*P.
3. The matrix representation for rotation in homogeneous coordinates is
a) P’=T+P
b) P’=S*P
c) P’=R*P
d) P’=dx+dy
Answer
Answer: c [Reason:] The matrix representation for rotation is P’=R*P.
4. What is the use of homogeneous coordinates and matrix representation?
a) To treat all 3 transformations in a consistent way
b) To scale
c) To rotate
d) To shear the object
Answer
Answer: a [Reason:] To treat all 3 transformations in a consistent way, we use homogeneous coordinates and matrix representation.
5. If point are expressed in homogeneous coordinates then the pair of (x, y) is represented as
a) (x’, y’, z’)
b) (x, y, z)
c) (x’, y’, w)
d) (x’, y’, w)
Answer
Answer: d [Reason:] If point are expressed in homogeneous coordinates then we add 3rd coordinate to the point (x, y), that is represented as (x’, y’, w).
6. For 2D transformation the value of third coordinate i.e. w=?
a) 1
b) 0
c) -1
d) Any value
Answer
Answer: a [Reason:] For 2D we have (x, y, 1) i.e. w=1.
7. We can combine the multiplicative and translational terms for 2D into a single matrix representation by expanding
a) 2 by 2 matrix into 4*4 matrix
b) 2 by 2 matrix into 3*3
c) 3 by 3 matrix into 2 by 2
d) Only c
Answer
Answer: b [Reason:] We can combine the multiplicative and translational terms for 2D into a single matrix representation by expanding 2 by 2 matrix representation into 3 by 3.
8. The general homogeneous coordinate representation can also be written as
a) (h.x, h.y, h.z)
b) (h.x, h.y, h)
c) (x, y, h.z)
d) (x,y,z)
Answer
Answer: b [Reason:] The general homogeneous coordinate representation can also be written as (h.x, h.y, h).
