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TEST 1 - CS528 
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Instructor Dr P Juell                   NAME_______________________ 
OPEN BOOK                                        May 7, 1992
100 points         
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1. (20)
A polyline is specified as points (0,-1), (1,0), (1,1), (-1,0), (0,-1).
Use these as the control points for a Bezier curve. Hand draw the 
coordinate system, the control points and then sketch in the Bezier curve.
The end points are as specified.  You do not have to calculate the  values
for the Bezier, but make sure that the curve has the correct overall shape
and goes in the appropriate regions.

2. (20)
The synthetic camera model does not have a center of interest specified.
Why does it not need it?

Specify the sequence of parametric form matrixes to adjust the synthetic
camera for viewing.  You do not have to specify, or work out, any numbers.
Do specify after the matrixes, the meaning of any variables you have used.

3. (20)
Specify true or false:

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_________ All points (other than black) in a color cube based on 
          a visible red, green and blue are visible.

_________ The point (0,1,0) in HSV is white.

_________ The points (0,0,0), (1,0,0), (1,.5,.5), (1,1,1) in a RGB
          color cube are increasing order of L in the HLS  system.

_________ You would expect that diffuse shading of a sphere from a
          single light source with a very few gray levels would
          cause a viewer to see Mach banding.

_________ For a single object fully in the view window, meeting the
          requirements for a convex polyhedron, simple back removable 
          is sufficient for hidden surface removal.
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4. (20)
Why is the scan-line hidden surface elimination technique presented
if the z-buffer technique produces correct answers.

Explain based on the two algorithms and the image complexity why
your answer is correct.

5. (20)
System A uses Phong shading and system B uses the true 
surface normal in the calculation.
Under what conditions might you notice a difference in the image of
the same object rendered by system A and B?
(Everything else is the same about the two systems).