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TEST 1 - CS528 
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Instructor Dr P Juell                   NAME_______________________ 
OPEN BOOK                                        March 26, 1992
100 points         
                          This sheet is to be turned in with the test
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1. (20)
Explain why Bresenham's line algorithm is important in the
current state of computer graphics.  This question asks to talk about the
field of computer graphics, not just drawing lines.

2. (20)
Two ways to store information are in raster and polyline forms.
Present two good reasons that information such as a outline of the US
would be better stored in a polygon rather than a raster form.

Present two good reasons for using raster over a polygon.

3. (20)
Write a routine (not a full program)
called SawTooth(x1,y1,x2,y2,Number_of_teeth) using any
routines you want from the book.  The points (x1,y1) represent the
start of a line and (x2,y2) the end.  The parameter Number_of_teeth will
specify how many teeth, or points will be drawn.  The points are to
be 10% of the line's length from the line.
For example SawTooth(0,0,1,0,3) would cause a line like:

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   /\\    /\\
  /  \\  /  \\
      \\/
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4. (20)
Wide screen movies are recorded as about 4 times wider than they are high.
This is often displayed in 'letter box' format.  That is enough space added
above and below the image left blank to allow the full image to go
from edge to edge.
Assume your display is 8 inches high and 10 inches wide.
Specify NDC for the screen boundaries, the viewport and the window for
displaying in letter box format.

screen

viewport

window

5. (20)
For a hypothetical fighter jet, the pilot has a joystick (J) and two
switches (A and B).  Moving the joystick forward and back causes the
plane's nose to go down and up.  Moving the stick left and right cause
the plane to turn in the same direction.  
One press of switch A (in three seconds)
selects  altitude, 2 presses selects fuel and three speed.
Pressing switch B for N seconds causes 
the status of the item selected by switch A to be spoken by
by the onboard computer every N seconds.

Classify each of J, A and B as: 
locator, stroke, string, valuator, choice or pick.
Also give a short reason for the choice.

J

A

B