Optional features for project 6

Optional Features for Project 6

10 pts: Implement a point light source and the distance attenuation factor in the lighting model. You might add a lamp to your picture.
10 pts: Add a specular component to the lighting model to get hilights.
15 pts: Implement transparency by casting refraction rays. A picture of the traditional glass sphere is fine, or be imaginative. The index of refraction of glass is about 1.5.

These features complete the following, more accurate, lighting model:

Here is what the new symbols mean:

phi is the angle between r and the reflection of the ray from light source i at p

specm is the specular reflectance of the surface (scalar)

shine controls how sharp the specular hilight is (usually > 1)

transparencym is the transparency of the surface

rt is the transmitted ray through the surface (a ray)

Some more, non-lighting oriented features:

10 pts: Antialiasing. Fire multiple rays through each pixel to get a much more realistic image. Try four.
5 pts: Make some interesting objects by combining convex objects.
15 pts: Build some interesting convex objects by intersecting simpler convex objects.
15 pts: Use an image as a texture on a plane or cylinder. It's fun to reflect the texture in a surface like a sphere.

While it's tempting to read the scene in from a file, I'd rather you work on graphics-related features, so I will give no extra credit for that.