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TEST 1 - CS528 
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Instructor Dr P Juell                   NAME_______________________ 
OPEN BOOK                                        April 20, 1990
100 points         
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1. (20)
For a B-spline curve give control points to approximate 
a circle with radius 1 and origin at (0,0).
Use as few control points as reasonable while giving the best curve possible.
(No, you do not have to have the exact values, give good estimates).

2. (20)
A triangle is specified with a center point at (2,3).
Turn the triangle 90 degree to the right ( _     |  )
around the center point.
Specify the matrix to perform this transformation.
Show and label your work.

3. (20)
One way to erase a segment from the screen is to perform an area fill
of the background color.
With multiple segments on the screen this creates a problem.
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What is the problem?
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What is simple (but possibly slow) solution?

4. (30)
[HARD BE THOROUGH]
Explain (in English) an algorithm to describe creation of a new
polygon C that is the result of subtracting polygon B from 
polygon A.
You are given polygons A and B as point lists.
(You can shorten the description by naming procedures and algorithms).

5. (10)
List the types of uses of the devices in the following.
First (a) the routine is selected from a menu,
then (b) the person signs their name,  finally (c) the user
selects which line is the start of their last name.

(a)

(b)

(c)