TEST 2 CS458

Instructor Dr P Juell    NAID______________________ NAME__________________________

100 points, closed book                                  Oct. 26, 2004
  1. (10) Give two examples where displaying a field of vectors would be useful.
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  2. (10) Assume a Bezier curve. Draw points to make a fairly reasonable script (or cursive) version of the word "cat". Everything is one line except the crossing of the t. It might help to put numbers by the points. (You are only to use enough points to control the curve, not to fully specify it.)
  3. (10) There are two different right hand rules we use. Both may give the same surface normal, but they come from different sources. What are they?
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  4. (15) I would like a nice cup, with insides and a handle. How you suggest creating such a thing? Do not make the process too complex or an extreme number of parts. Specify in some detail. You might want to draw to make your explanation clearer.
  5. (10) You are supplying computer graphic images for a horror movie and the director decides she wants curves GUARANTEED NOT to have type 2 continuity. (She says this will make sick looking skin). How could you do this? Remember, you needed to GUARANTEE the curve does not have type 2 continuity, not just that it might not.
    HINT: In Zero order (parametric) continuity, the curves meet. Type 1 continuity tangents are equal at the joining point. Type 2 continuity both first and second derivatives are the same at the joining point.
  6. (10) If your pointer device supported only event input, give an example of something common that would be easy to do.
    Give an example of something that could not be done, or would be very hard.
  7. (10) Give an example of something that would be easy to build using CSG. Also, why would it be easy?
    Give an example of something that would NOT be easy to build using CSG. Also, why would it not be easy?
  8. (15) When we display close to the viewer we need more details for it to look good than for distant items. Since the amount of detail can also effect the the amount of computer time required to display the item, we may well want to save time in rendering distant items. Pick a technique presented in class and say how we could get this tradeoff using that technique. (This is called level of detail (LOD)).
  9. (10) The attached page has a surface weather map for Oct 27,2002. What is the difference in weather at Grand Forks (GFK) and Fargo (FAR) shown on the map?

    region surface weather map

    close up of ND detail of the Red River Valley