Surface Features
- Uses Phong shading (two params; specular base color and Phong coeff)
- Parameters include transparency, index of refraction, ambient lighting
(``default'' color, unaffected by rays), diffuse color
- Builtin textures include blotch, bump (random deltas to normal
vector), checker, cloud, fbm (fractional Brownian motion), gloss,
marble, wood
- Can map arbitrary images onto objects using one of four texture
mapping schemes: map uv (uses builtin mapping), linear,
cylindrical, spherical