Problem 1: Light sources are required to define shading effects, what are the other three components?
Problem 2: In the Phong model, what are the three types of lighting Ia, Id, Is?
Problem 3: This graph shows the vectors of a point P on a surface: n is the surface normal, l is the direction to a light source, v is the direction to a viewer, what is r? And how to compute 'r'?
Problem 4: Write down the equation used to compute the intensity at P with Phong shading model (explain the meaning of the new vectors or coefficients).
Problem 5: Blinn modified the Phong model. What is the equation with Blinn model? (Explain the meaning of the new vectors or coefficients). What is the benefit of this modification?