MCQ | Line Drawing Algorithms in Computer Graphics

Multiple choice questions and answers (MCQ) based on the Line Drawing Algorithms in computer graphics with 4 choices, correct answer and explanation.
Submitted by Monika Sharma, on October 12, 2020

Question 1: What is the formula for calculating the slope 'm' of a line?

m = dx / dy
m = dy / dx
y = mx + c
None of the above

Answer: b. m = dy / dx

Explanation:

The slope of a straight line is calculated using the following:

m = (y2 – y1) / (x2 – x1)
m = dy / dx

Question 2: Which of the following is a line drawing algorithm?

Line equation algorithm
Digital Differential Analyzer (DDA) algorithm
Bressenham's algorithm
All of the above

Answer: d. All of the above

Explanation:

All the mentioned algorithms: Line equation algorithm, the DDA algorithm and the Bressenham's line drawing algorithm are used for line drawing in computer graphics.

Question 3: Which of the following statements is not true with respect to the Digital Differential Analyzer (DDA) algorithm?

It is an incremental method of scan conversion of line
In this method, calculation is performed at each step but by using the results of previous steps.
This algorithm can also be used to draw circle
None of the above

Answer: c. This algorithm can also be used to draw circle.

Explanation:

The DDA algorithm is applicable only for line drawing. Circle cannot be drawn using this algorithm. For circle drawing, there are other algorithms available like the mid-point circle drawing algorithm, etc.

Question 4: Which of the following options is not correct according to the definition of Bresenham's line drawing algorithm?

It gives a close approximation of points of line by determining n-dimensional raster that should be selected.
It is an incremental error algorithm.
It gives exact line points.
None of the above

Answer: c. It gives exact line points

Explanation:

It gives a close approximation of points of line by determining n-dimensional raster that should be selected.

Question 5: "The Digital Differential Analyzer (DDA) algorithm is an incremental method of scan conversion of line."
Based upon the above statement, determine whether the following condition is true or false.
"The DDA algorithm uses the results of previous step for determining the value of the next step."

True
False

Answer: a. True

Explanation:

As the DDA algorithm is an incremental algorithm, it uses the previous values for determining the next values.