Computer graphics assignment questions and answers

Computer Science Graphics Assignment

Individual Final Assignment 2019 - 2020

Module Title Computer Graphics

Module Leader Prof. Dr. Samir El-Seoud Semester: Two

Assessment Weight 60% of the total course mark

Due Date Tuesday, 9.6.20 at 10:00 pm

Instructions to Students:

• This exam is 3 pages long and contains 5 questions

• Answer all questions.

• This assignment is only 12 hrs long.

• The total mark of the exam is 100 marks. The approximate allocation of

marks is shown in brackets by the questions.

• The word “Drive” indicates you MUST prove.

• The word "Describe” indicates you should only write down without prove.

• You must show explicitly your calculations and not only final results,

especially in matrix multiplications.

• Submission:

o Use the answer booklet provided on the e-learning, then append

your answers starting the following page.

o Use Ariel 12 font, justified text and 1.5 spacing.

o Save the file as a pdf, the file name is:

GraphicsFinal_YournameYouID.pdf

(e.g GraphicsFinal_Omar123456.pdf)

o Upload the assignment to E-Learning by the deadline. Answer,

MUST be submitted online on the e-Leaning website. No e-mails.

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• Academic Honesty:

o Copying of text from any source, or getting help from any person

is a plagiarism. If any plagiarism case is detected, a misconduct

report will be filled and BUE regulations will be applied.

o Copy and paste will be considered as plagiarism, even from our

textbook or posted slides. Use your own words and your own

text.

o Plagiarism will NOT be tolerated, and zero grade will be

assigned.

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Q1 Define Briefly each of the following items: [2 marks each]

Use your own words to define briefly each of the following items. Copy and

paste from a source will be considered plagiarism and zero mark will be

assigned.

1. Display Controller

2. Animation

3. Graphics Processing Unit (GPU)

4. Rendering

5. Transformation

6. Vanishing Point

7. Image processing

8. Clipping

9. Composite Transformation

10. Perspective foreshortening

[Q1: Total 20 Marks]

Q2

Show all matrix multiplications. Use your own work.

1. Describe the transformation that rotates an object point, Q(x, y),  degrees

about a fixed center of rotation P(h, k). [3 Marks]

2. Drive the general form of the matrix for rotation about a point P(x, y).

[4 Marks]

3. Use a homogeneous matrix transformation to perform a 300 rotation of

triangle A(0,0), B(1,3), C(5,2) about P(-1,-1). [5 Marks]

4. Determine the new coordinates of the rotated triangle. [4 Marks]

5. Draw the original and the rotated triangle. [4 Marks]

[Q2: Total 20 Marks]

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Q3

1. Describe the transformation ML which reflects an object about a line L. [3 Marks]

2. Drive the explicit form of the matrix ML for reflection about a line L with slope m and y intercept (0, b). [7 Marks]

3. a. Reflect the L-shape whose vertices are A(-6,3), B(-4,3), C(-4,1),

D(-2,1), E(-2,0), and F(6,0) about the line y=x [8 Marks]

b. What are the new coordinates of the reflected object? [2 Marks]

[Q3 Total: 20 Marks]

Q4

Show that the order in which transformations are performed is important by the

transformation of the triangle A(1,0), B(0,1), C(1,1), by:

a. rotating 450 about the origin and then translating in the x-axis direction

one unit, and [8 Marks]

b. translating and then rotating. [8 Marks]

In each case, find the new coordinates of the transformed triangle ABC

[4 Marks]

[Q4 Total: 20 Marks]

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Q5

Let an axis of rotation L be specified by a direction vector V= 2J and a location

point P(0,1,0).

Used 2 different methods (short and long method) to find the

transformation matrix for a rotation of 450 about L.

Refer to the figure below for a general vector V=aI+bJ+cK, a point P(x,y,z), and

object rotation of angle θ0 about L.

a. Short method [8 Marks]

b. Long method [12 Marks]

[Q5 Total: 20 Marks]

Z

V L

•P

K Q θ Q′

Y

X