Z-buffer hidden surface elimination algorithm

Question

Q1. Write down the transformation matrix to get top view of the object on XY plane of the screen.

Q2. The four control points P₁(x₁,y₁), P₂(x₂, y₂), P₃(x₃, y₃), P4(x₄, y₄), are given work out the starting slope of the cubic Bezier curve.

Q3. While performing the polygon scan conversion, explain how do you treat the case if a scan line passes via a vertex of the polygon?

Q4. Define the terms:

a) Foreshortening factor                                                                                                  
b) Floating Horizon
c) B-spline curve

Q5. Describe the relative advantages and disadvantages of Z-buffer hidden surface elimination algorithm over the scan line Z-buffer algorithm.

Q6. Explain the diffuse and specular light reflection modeling in the computer graphics.

Q7. Write brief notes on:

a) Half-toning
b) CSG models