02/04/2003
15-462 Graphics I
20
Lambert’s Law
•Intensity
depends on angle of incoming light
•Recall
l
= unit vector to light
n
= unit surface normal
q = angle to normal
•cos q = l ˘
n
•Id = kn (l ˘ n) Ld
•With
attenuation:
q = distance to light source,
Ld = diffuse
component of light
