CSCI 360

Fall 2013, Test 2

  1. Interpolation
    1. [4 points] Describe at least two different applications of interpolation in the graphics pipeline.
    2. [2 points] Given a value x and y, give a formula which will provide interpolation from the value x to y.
    3. [2 points] Describe how to apply the formula in part B.
  2. [5 points] An orthographic projection employs the following projection matrix: 
    | 1 0 0 0 |
| 0 1 0 0 |
| 0 0 0 0 |
| 0 0 0 1 |
    What happens when such a projection matrix is applied? Give a description in English, and possibly a picture.
  3. View Frustum
    1. [2 points] What is a view frustum?
    2. [1 point] How is the view frustum related to the view volume?
    3. [2 points] How are objects in the view frustum prepared for clipping?
  4. Lighting
    1. [9 points] Name and describe the three major components used in the illumination function.
    2. [2 points] Describe The difference between flat shading and smooth shading.
    3. [5 points] Describe the advantages and disadvantages to flat shading. Where is flat shading done in the openGL pipeline?
    4. [4 points] Describe the advantages and disadvantages of the way shading is approached in the current version of openGL.
    5. [4 points] What is a fragment and how is shading applied to fragments?
    6. [5 points] Describe the data associated with a surface necessary to compute shading.
    7. [3 points] Select the correct answer to the following: 
      The use of a halfway vector in the calculation of a specular term  is called.
        A. the Blin-Phong lighting model
	B. the Broken-Bragg lighting model.