Question

Given below are different properties of 3D projections from A-D. Identify the correct order on the basis of property true of (i) a perspective projection only, (ii) an orthographic projection only, (iii) both orthographic and projective transformations and (iv) neither orthographic nor projective transformation, respectively.

(A) Straight lines are mapped to straight lines.

(B) Distances and angles are (in general) preserved.

(C) Far away objects appear the same size as closer ones

(D) Requires homogeneous coordinates in order for it to be encoded into a linear transformation.

Choose the correct answer from the options given below: 

1. D, C, B, A
2. B, C, D, A
3. D, C, A, B
4. C, D, B, A

Answer 1

Correct Answer - Option 3 : D, C, A, B

The correct answer is option 3.

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	3D projections		Properties
(i)	a perspective projection only	(D)	Requires homogeneous coordinates in order for it to be encoded into a linear transformation
(ii)	an orthographic projection only	(C)	Far away objects appear the same size as closer ones (as orthographic projection  preserve dimensions)
(iii)	both orthographic and projective transformations	(A)	Straight lines are mapped to straight lines (in both)
(i)v	neither orthographic nor projective transformation.	(B)	Distances and angles are (in general) preserved

 

∴ Hence the correct answer is D, C, A, B.