I realized that I can just substitute
the actual picture (_color) with a plain color
Included are two pictures. The goal here
is to have a room with a light in the center of it
with proper speculars on the walls.
In picture "1" you can see a light in the
center af a room. In picture "2" you can see the
speculars are not similar between the walls.
One solution might be to disable the effects
of the light for my walls, since (in my case) the walls
and the light aren´t moving. There will be objects in the
room that cast shadows to the walls, though.
There is practically no use of computing the
walls apart the shadows.
If you figure out how to have proper speculars
to my walls that would be a fine thing.