FINAL - CS458 Fall 2000

FINAL - CS458 

Instructor Dr P Juell                         NAME_______________________ 
CLOSED BOOK                                        Dec 21, 2000 10am-12pm
200 points
There are 220 points presented on this test. Work 200 points of problems. The first 200 points attempted will be graded. If a problem is not to be graded, put a line through it.

  1. (10) Why would you like a grey scale monitor even if the images are strictly of black and white items.
  2. (10) What is the odd-even rule for area filling?
  3. (20) A cone is centered at (3,2,1). Specify the string of transformations (T(x,y,z),S(x,y,z),Rx(a),Ry(a),Rz(a)) to turn this upside-down at this point in space. Then write the string of matrices corresponding to the transformations. Do NOT multiply the matrices. If this is too hard, for 15 points do: .br 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 transformations and matrices to perform this transformation.

    Transformations (in book order):

    Matrices (in book order):
  4. (10) What is the purpose of "intensity cueing" in a wire frame display?
    What is one technique that could be used for "intensity cueing"?

  5. (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.
  6. (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).
  7. (20) Specify numbers in order from 1 (fastest) to 10 (most computations) for each of the following items. 
    ___ ray tracing (with all objects opaque)

___ ray tracing (with transparent objects)

___ radiosity 

___ z-buffer with uniform color for each object

___ painters algorithm (using shading formula)

___ Phong shading (for all objects)

___ Gouraud shading (for all objects) 

___ wire frame

___ wire frame with hidden line removal

___ display of prepackaed image
  8. (20) For a normal viewing volume clipping, specify the various ways that nothing will be display of an object that exists in the world coordinates.
  9. (10) What does a green screen in TV or a blue screen in movies allow you to do?
  10. (20) Give a station reporting symbol (glyph) for 15 knot winds from the North with 75% cloud cover with a temperature of -5 and dewpoint of -10.

    Why are these glyphs used instead of just false coloring the information onto the weather map?
  11. (10) How could you tell if an animation film loop was used?

    Why does this effect not seem to bother the viewer?
  12. (10) Raytracing produces very nice specular highlights on objects. What additional effect do we use Radiosity for?
  13. (10) Give an example of applying a texture.
  14. (20) In HSV (0,1,1) is Red. Specify HSV and RGB values for the following colors:
    color (H,S,V) (R,G,B)
    pink
    _
    white
    _
    black
    _
    gray
    _
    dark red
    _

  15. (10) Give an important reason for fractals being used in creating images.