Computer Science 455

Instructor: R. P. Burton

First Quiz

January 23-24,2006

Name _________________________________________ Score ____________/24

1. What first suggested the idea of using computers to do graphics?

   1. man’s natural yearning for pictures (rather than tables of numbers)

   2. the presence of television sets in virtually every household

   3. the presence of oscilloscopes (to keep early computers running)

   4. the search for an alternative for flight training

(c)

2. Graphics techniques were well understood during the 60s, but computer games using these techniques did not become popular until the late 70s. What was the principal reason?

   1. persistent popularity of pinball machines

   2. public ignorance of computer graphics

   3. it took that long for someone to think there was “a buck to be made” with computer games

   4. the cost of memory and processors

(d)

3. Graphics simulators are popular for modeling dock gantry cranes, but not skateboards. Why?

   1. skateboards are cheap; cranes are expensive

   2. skateboards pose less risk (or personal injury and/or property damage) than cranes

   3. it’s not cost-effective to simulate skateboards

   4. (all of the above)

(d)

4. Computer-aided architectural design can best be characterized as

   1. automating traditional architectural design

   2. automating and enhancing traditional architectural design

   3. substituting new (and different) activities for the traditional design activities

(b)

5. Why did the use of computer graphics for residential architecture not become commonplace until the early 90s?

   1. no one thought to use computers for drafting

   2. there was a housing slump throughout the 80s

   3. it was not cost effective to do so

   4. computer graphics techniques were not sufficiently advanced until the early 90s

(c)

6. How did Disney react to the suggestion that computers could be used to do animation?

   1. with excitement; hand-drawn animations had become too expensive to produce

   2. with disbelief (that computers could be used to produce pictures)

   3. with disinterest (or even disdain that an artistic endeavor could be done by a machine)

(c)

7. Since “a picture is worth a thousand words,” computer graphics is appropriate and desirable for teaching such concepts as circuit behavior, relativistic length contraction, and molecular behavior.

   1. true

   2. false

(a)

8. Due in large part to the risks to human subjects (and the resultant liability), computer graphics has minimal application in medical applications, especially invasive medical applications.

   1. true

   2. false

(b)

9. For consumption “by the common man,” computer graphics applications are limited to phenomena which the common man can observe in the natural world, cartoons and animations being the only significant exceptions.

   1. true

   2. false

(b)

10. One of the major contributions of computer graphics to society in general was the development of the CRT which subsequently made television possible.

    1. true

    2. false

(b)

11. Early CRTs used in graphics were monochrome. Hence, only with the development of multi-color monitors did it become possible to render colored scenes and scenarios.

    1. true

    2. false

(b)

12. The Sketchpad system developed by Ivan Sutherland in the early 60s was a point-plotting display. With the subsequent advent of vector graphics, the point-plotting techniques of the early 60s became permanently obsolete.

    1. true

    2. false

(b)

13. The disadvantage(s) of the CRT relative to other display devices is(are)

    1. weight

    2. voltage requirements

    3. both (a) and (b)

(c)

14. A full-color CRT has been built by providing

    1. three layers of phosphor – one red, one green, one blue

    2. triads of red, green, and blue phosphors

    3. both (a) and (b)

(b)

15. The image to be displayed on a Direct View Storage Tube (marketed by Tektronix) is stored

    1. in a frame buffer

    2. in a display file in a separate refresh computer

    3. in a storage grid which is part of the display

    4. in a high persistence phosphor

(c)

16. Motion pictures are presented flicker-free at 24 frames/second. There is no practical advantage to refreshing (nonstereo) graphics images more than 24 times/second.

    1. true

    2. false

(b – graphic images fade)

17. The DDA algorithm is to be used to draw a line from (200,100) to (800,900). Approximately how many steps are taken?

    1. 600

    2. 800

    3. Sqrt(600² + 800²)

    4. 600 + 800

(b)

18. A properly written DDA algorithm likely will contain a _____ operation.

    1. trunc

    2. round

(a)

19. A DDA that takes 127 steps will always run faster than a DDA that takes 128 steps.

    1. true

    2. false

(b)

20. To do a scan-line fill using a bucket which stores all the intersections of all the scan lines with all the edges, vertices should be treated as

    1. no intersection

    2. one intersection

    3. two intersections

    4. (it depends)

(d)

21. Suppose you wish to do a scan-line fill using an active edge list. Suppose two edges AB and BC are associated with vertex B. The coordinates of vertex C are (100, 300), the coordinates of B are (200, 700), and the coordinates of A are (250,100). Which edge goes on the active edge list first?

    1. AB

    2. BC

    3. It makes no difference

(b)

22. Plasma panels started out with one color (orange), one intensity of that color, and a resolution of about 60/inch. Plasma panel displays are still monochrome, still one intensity, and still low resolution.

    1. true

    2. false

(b)

23. Thin-film electroluminescent displays are most similar in concept to

    1. CRTs

    2. DVSTs

    3. Plasma panels

    4. LCD displays

    5. LED displays

(c)

24. Which of the following represents or produced true, simultaneous 3D output?

    1. MIT’s rotating LED panel

    2. A hologram

    3. A Viewmaster®

    4. None of the above

(d)