Y
ITEC2110 Fall 2007 Test 2, Dr. Jim Rowan
Name________________________________
3
2
1
22
24
90
15
89
79
17
43
94
75
77
47
45
72
33
1 2 3 4 5
X
1) In the above table, what number is in the cell (4,2)?
Y
2
1
0
1 2 3
2) In the vector shown above, what is the (x,y) displacement?
X

(0,0) computer screen
(350,210) application window
Y
(1024, 768)
3) In the diagram above a computer screen is shown with an open application window.
What are the absolute coordinates of the upper left corner of the application window?
4) What are the relative coordinates of the upper left corner of the application window?
(0,0) computer screen
503 713 835
X
210
375
410
Y
(1024,768)
The diagram above shows a number-8-shaped object (at an angle) that is displayed on a computer screen.
5 & 6) Give the pair of (x,y) coordinates of the bounding box that contains that object.

(0,0) computer screen
X
(0,0) computer screen
Y
(0,0) computer screen
A
A
(1024,768)
X
Y
(0,0) computer screen
B
A
Y
A
Y
A
C
(1024,768)
D
7) Which of the diagrams above shows the object (labeled “A”) translated to a different position?
8) Which of the diagrams above shows the object (labeled “A”) reflected across a line that is parallel to the X axis?
9) Which of the diagrams above shows the object (labeled “A”) that was first rotated around the center of its bounding box and then translated?
10) Which of the diagrams above shows the object (labeled “A”) reflected across a line that is parallel to the Y axis?
X
X
(1024,768)
(1024,768)

A
B
A
B
D
E
Constructive solid geometry is one form of 3D modeling. The image above shows 5 objects labeled A, B, C, D & E.
11) Which object best represents an object that was created by forming the intersection of objects A and B?
12) Which object best represents an object that was created by forming a union of objects
A and B?
13) Which object best represents an object that was created by forming a difference of objects A and B?
In this class we discussed the three different forms of 3-D Modeling: Procedural
Modeling, Free Form Modeling and Constructive Solid Geometry.
14) Extrusion is a version of one of these forms. Which one?
15) Particle systems are a version of one of these forms. Which one?

16) Using an object’s structural hierarchy is one means of coping with complexity.
Explain what structural hierarchy is and give an example. (use the back of the page if more room is needed)
17) Lighting a 3-D object realistically is complex. Ray tracing is one way to light a scene that produces photo realistic results even when there are multiple objects in the scene.
What does ray tracing take into account allowing it to produce these photorealistic results?
The image above measures 3 pixels by 3 pixels.
18) Without data compression, how many bytes would be required to represent this image using RGB encoding?
19) If that same image were compressed using RLE data compression, write out the string of bytes that this compression would produce.
20) Why would a JPEG compression routine be a poor choice to compress a file that contains scientific data (other than the obvious “it’s not an image”)?
21) What is it about human vision that JPEG image compression takes advantage of in order to compress a file?
22) What is one artifact of compression that an image file can exhibit when using JPEG compression?

Convolution is one method that can be used to create an image filter. It allows the pixels surrounding a pixel have an effect a that pixel. It accomplishes this task using a convolution mask.
23) Fill out the convolution mask below so that only the pixels to the immediate right and to the immediate left ---but not the pixels above or below-- will evenly affect the computation.
24) Can a 1 bit mask provide levels of transparency? Why or why not?
25) Given the Convolution Mask and the Original Image below, what would the new value of the pixel that is marked with an X in the New Image? Show your work to get partial credit!
X
New Image
255
255
195
135
255
63
0
45
205
250
45
72
27
201
202
0
144
126
0
230
Original Image
190
10
20
90
0
1/9 1/9 1/9
1/9 1/9 1/9
1/9 1/9 1/9
Convolution
Mask

Finally, I am requesting your help to make this class better for future students...
Please circle your choices below
This will not affect your grade at all. In fact, do not write your name on the last page and tear off this back sheet before you turn this test in.
If you don’t care to participate, just tear off the last page and turn it in unmarked.
Statement 1:
I have found that the book has been helpful in studying for the tests taken thus far in this class.
(circle one)
Disagree Strongly Disagree Neither agree or disagree Agree Agree strongly
Statement 2:
I have found that the posted powerpoint presentations have been helpful in studying for the tests taken thus far in this class.
(circle one) you?
Disagree Strongly Disagree
Statement 3:
Neither agree or disagree Agree Agree strongly
I have found that accessing and listening to the in-class-recorded powerpoint presentations has been helpful in studying for the tests taken thus far in this class.
(circle one)
Disagree Strongly Disagree Neither agree or disagree Agree Agree strongly
And finally...
In your own words, can you think of something that I can do to make this class better for

;-)
Thanks!