[mg14724] Mathematica Lightning Model?

[Alexander Otte]

Hi!

How can it be, that the shading of an object depends on the distance
between object and viewer?

The following line of code shows the problem:

Plot3D[Sin[x] Cos[y],{x,0,2 Pi},{y,0,2 Pi},

LightSources->{{{1,0,1},RGBColor[1,0,0]}},ViewPoint->1000{1.3,-2.4,2.0}]

The surface is rendered with a single color. Even if an object is far
away - should't the intensity of diffuse reflected light depend on the
angle between the surface normals and the direction of light?

So what kind of lightning model (lightning equation) does Mathematica
use?

Thanks

Alex