Date: Jan 7, 2013 12:36 AM
Author: Alexey
Subject: "Directional" light and ImageScaled coordinates (a bug?)


It seems that "Directional" light specification with the direction of the
light specified by a vector defined by two points
{"Directional", col, {pt1, pt2}}
ignores the second point 'pt2' when ImageScaled coordinates are used.
Compare:

Graphics3D[{White, Sphere[]},
Lighting -> {{"Directional", Green, ImageScaled[{0, 0, 1}]}}]
Graphics3D[{White, Sphere[]},
Lighting -> {{"Directional",
Green, {ImageScaled[{0, 0, 1}], ImageScaled[{0, 0, 0}]}}}]
Graphics3D[{White, Sphere[]},
Lighting -> {{"Directional",
Green, {ImageScaled[{0, 0, 1}], ImageScaled[{1, 0, 1}]}}}]

I see no difference between the outputs from above in the version 9.0.0. Is
it a bug?

Sincerely,
Alexey Popkov