CSC 461: Computer Graphics I
(Fall 2006)
Assignment 5
Due December 8, 2006
- (Ex.
6.2) Often, when a large polygon is shaded by OpenGL, it is rendered
brightly in one area and more dimly in others. Explain why the image is uneven.
Describe how you can avoid this problem
- (Ex.
6.3) In the development of the Phong reflection
model, why do we not consider light sources being obscured from the
surface by other surfaces in our reflection
model?
- (Ex.
6.4) How should the distance between the viewer and the surface enter the
rendering calculations?
- (Ex.
6.19) As geometric data pass through the viewing pipeline, a sequence of
rotations, translations, scaling, shearing, and a projection
transformation is applied to the vectors that determine the cosine terms
in the Phong reflection model. Which, if any, of
these operations preserve the angles between the vectors? What are the
implications of your answer for implementation of shading?