The design of framework references "Realistic Ray Tracing" by Peter Shirley and R. Keith Morley

First I generated images as on the Webpage: using the 200-face bunny model
twoandOne.png   Running time: 12 seconds or so

This one is after interpolating the normal(I don't think it looks exactly the same as the one on the webpage)
interpolate.png   Running time: 12 seconds

This one has two spheres(parametric) and one 1k bunny and one 200-face bunny with the same shading parameters under one white light twobunnies.png   Running time: 68 seconds

This one has two spheres(parametric) and one 1k bunny and one 200-face bunny with the different shading parameters(kd, ks, ka, n) under one white light:
red ball: color(1.0, 0.0, 0.0), shading parameters(0.7, 0.3, 0.2, 30)
green ball: color(0.0, 1.0, 0.0), shading parameters(0.5, 0.5, 0.1, 3)
white bunny: color(1.0, 1.0, 1.0), shading paratmers(0.4, 0.6, 0.3, 2)
yellow bunny: color(1.0, 1.0, 0.0), shading parameters(0.3, 0.2, 0.5, 3)
differentParam.png   Running time: 64 seconds

After implemented sampling:
sampled-output.png   This one is given original input 512x512. Running time: 64 seconds

Another image of super sampling:
sampled-output1.png   This one is given original input 1024x1024. Running time: 254 seconds