Assignment 4

Part 2

Question 1

asdf

Part 3

Question 2

There is less noise in regions of the floor where the specular highlight is very likely to reflect the yellow light source. Since the yellow light source is very large, in the area of floor where specular rays tend to reflect towards the yellow light, these rays are quite likely to intersect the yellow light. It's reflection is therefore consistently visible and noise is low.

The area of the floor whose specular highlight is very likely to reflect the blue light, however, has severe noise. Because the blue light is very small, few rays which reflect towards it actually intersect it and the blue light's reflection appears in few samples.

Question 3

When sampling only the light source in this scene, the worst case noise from the bsdf-only render becomes the best case and the best case from the bsdf-only render becomes the worst case.

The blue light's reflection, which formerly appeared as sparse noise, looks nearly perfect. Since the light is quite physically small, consecutive sample rays strike at similar locations and give extremely consistent results.

However, the yellow light's reflection is fairly noisy due to the large surface area being sampled over. The variance of angle and distance between consecutive sample rays is large enough to show significant noise.