TEST 1 CS728

Instructor Dr P Juell    NAID______________________ NAME__________________________

100 points, closed book                                  Feb. 11, 2003
  1. (10) The active LCD displays have a built in memory for each pixel. That gives them the effect of infinite persistence and yet allows instant change. Give two changes this would permit over the traditional CRT based systems.
  2. (10) Give the technical term for two uses of a pointer and an example of this use.



  3. (10) What is a "texture map" and how is it used?


  4. (15) A group is trying to do visualization of Wall Street stocks. They produce an image with a number of animals in it. Each animal has the identifier for a stock on it, e.g. IBM, Intel, Apple. There are three different animals: bulls, bears and sheep. Individual animals are colored from red to blue. The animals are each in one of three positions: sitting, standing, jumping. What are these properties (animal type, color etc.) being used for?


    Would you normally expect a consistent relationship between any two of these properties?
    Why or why not?


    What would you hope to be able to get out of this type of visualization?
  5. (10) The hardware for a monitor has a pallet lookup table. The table has 16 entries each with 30 bits. What does this tell us about the size of the display buffer memory and the number of colors that can displayed?


  6. (15) Two cones, A and B, are in 3D space with their centers at (13,6,0) and (13,2,0) respectively. The two cones have their tips touching. They are each 4 units hight, have a base radius of 2 units. They each have their center on the line from the center of the base circle to the point, at half way on the line. Specify the steps to change them so their bases are touching at the same locations. Object A is to be reduced to half size. Specify the string of transformations (T(x,y,z),S(x,y,z),Rx(a),Ry(a),Rz(a)) the the required changes. Use either a shorthand notation as given or specify the transformation matrix for each step. Do NOT multiply the matrices.
    If this is too hard, for 10 points do: A triangle is specified with a center point at (2,3). Turn the triangle 90 degree to the right ( _ | ) around the center point and double is size. Specify the transformations and matrices to perform this transformation. 
        starting state
|        \------/
|         \ .  /  . at (13,6,0) object A
|          \  /
|           \/
|           /\    touch point (13,4,0)
|          /  \
|         /  . \   . at (13,2,0) object B
|        /------\
+------------------

         final state
|           /\    . at (13,5,0) object A
|          /--\
|        \------/
|         \ .  /  . at (13,2,0) object B
|          \  /
|           \/
+------------------
  7. (10) If you are using OpenGL to show a scene that you are flying into, you run into a trade off bewteen image quality and display speed. Give an example that would have this type of problem.


    Give a way you could address this problem.


  8. (10) Characters can be stored in bit mapped and stroke notation. Give a good reason for wanting to use each.



  9. (10) You are presenting a moving scene in OpenGL. What do you as a programmer have to do to get a line displayed on the screen and when?