Computer Science 455

Instructor: R. P. Burton

First Quiz

January 22-23, 2007

Name _________________________________________ Score ____________/29

1. Which of the following provided the greatest impetus for using computers to draw pictures?

   1. televisions which became commonplace during the preceding decade

   2. oscilloscopes which commonly were present to repair and maintain computers

   3. the need to depict the trajectories of projectiles

   4. the desire to reduce the tedium and repetition of the drafting process

   5. the desire to eliminate the tedium of the “in betweening” process required for animation

(b)

2. Immediately following Ivan Sutherland’s work in the early 1960s, computer graphics sprang into widespread and enthusiastic use by a wide variety of users.

   1. ture

   2. false

(b)

3. The application of computer graphics to architectural design began with ______ and progressed ultimately to ______.

   1. simple residences, large office buildings

   2. large office buildings, simple residences

(b)

4. The automated weaving of rugs and tapestries _______ the advent of computer graphics.

   1. preceded

   2. followed on the heels of

(a)

5. Accurate manifestation of the laws of physics is ________ to the developers of video games ________ it is for the developers of vehicle and accident simulations.

   1. as important, as

   2. much less important, than

(b)

6. Scientific phenomena which are not visible to the natural eye cannot be presented graphically with any real expectation that the typical high school graduate will understand them.

   1. true

   2. false

(b)

7. What is a cathode ray?

   1. a stream of electrons

   2. a stream of protons

   3. a stream of neutrons

   4. a steam of photons

(a)

8. What is the aiming mechanism in a cathode ray tube?

   1. the cathode

   2. the control grid

   3. the focusing system

   4. the deflection system

(d)

9. Which occurs second (relative to the other two)

   1. fluorescence

   2. phosphorescence

   3. refresh

(b)

10. High persistence phosphors are not used primarily because of the cost of the required materials.

    1. true

    2. false

(b)

11. The density of points on a display surface of a CRT should be such that the next “point” begins when its neighbor’s intensity has dropped to ____ of the intensity at its center.

    1. 90%

    2. 60%

    3. 10%

    4. 0%

(b)

12. Assuming one byte for red, one byte for green, one byte for blue, and a 480 x 525 display, how big does the frame buffer need to be?

    1. about 250 KB

    2. about 500 KB

    3. about 750 KB

    4. about 1 MB

    5. about 3 MB

(c)

13. What is scan conversion?

    1. interlacing so all the odd scan lines are drawn, then all the even scan lines, then all the odd scan lines …

    2. drawing calligraphically (each element in its entirety before proceeding to the next screen element)

    3. determining a screen representation from a geometric representation

(c)

14. The principal limitation of a beam-penetration CRT is

    1. speed

    2. no erasure

    3. limited color

    4. limited resolution

(c)

15. A shadow-mask CRT has more than one

    1. electron gun

    2. deflection system

    3. focusing system

    4. (all of the above)

(a)

16. A direct view storage tube has more than one

    1. electron gun

    2. deflection system

    3. focusing system

    4. (all of the above)

(a)

17. The principal limitation of a plasma panel is

    1. speed

    2. no erasure

    3. limited color

    4. limited resolution

(a)

18. Plasma TVs, of the type you might buy from an electronics store, are filled with

    1. neon-based gas

    2. a doped, liquid plasma

    3. a phosphor (such as zinc sulfide)

(c)

19. Liquid crystal (as in an LCD display) is transparent when the molecules are

    1. aligned so the light is not twisted

    2. not aligned so the light is twisted

(b)

20. Which of the following produce true 3D output?

    1. polarized glasses and bimodal projection

    2. colored lenses and colored images

    3. shuttered images

    4. all of the above

    5. none of the above

(e)

21. There is no such thing as a true 3D output device, even though some output devices create the illusion of 3D.

    1. true

    2. false

(b)

22. Why is there an LED display, but no display made of incandescent lights?

    1. lower power requirements (for LEDs)

    2. faster on/of times (for LEDs)

    3. greater durability (of LEDs)

    4. all of the above

(d)

23. Why are Trinitron screens flat, top to bottom?

    1. they aren’t!

    2. the deflection mechanism is designed for a sphere of effectively infinite radius

    3. they use bands of color rather than triads of color

(c)

24. Laser display devices write

    1. directly on the screen

    2. on photochromic film, producing images which can be projected onto the screen

    3. either (a) or (b)

(c)

25. What sort of “glasses” are needed to see 3D in random dot autostereograms?

    1. polarized glasses

    2. colored glasses

    3. shuttered glasses

    4. no glasses

(d)

26. If a particular scene consists largely of rectangles of constant color, which of the following would be more efficient in terms of storage?

    1. cell encoding

    2. run-length encoding

    3. (a) and (b) would be equivalently efficient

(a)

27. To determine movement, the mice of today no longer need wheel or a ball, nor do they need a surface with grid lines. But, at a minimum, they require a surface with detectable texture; without such a surface even the most sophisticated mice cannot function.

    1. true

    2. false

(b)

28. The spaceball is limited in the range of values it can produce in x, y, and z because the ball cannot be move arbitrarily far in each of those directions.

    1. true

    2. false

(b)

29. What is the dimensionality of an image received by a human retina?

    1. one

    2. two

    3. two and a half

    4. three

    5. four

(b)