A lambertian object obeys Lambert’s cosine law.
Color of a surface is proportional to the cosine of the angle between surface normal and direction to light source
c ∝ cos θ
- If a surface points away from light, it should receive no light.
- Smaller angles -> higher chance that light is reflected back
- Larger angles -> reflection light gets weaker, it is likely shadowed/masked
- No dependence on camera angle
References: Tutorials Point