Mike Horvath <mik### [at] gmailcom> wrote:
> I ended up using this:
>
>
> // This script assumes the depth effect is *linear* from near to far,
> which may not be the case.
>

The idea looks interesting! And your model proves that it works.

In the interim time, I had a brainstorm. I had to work it out graphically on
paper, discarding one idea after another, but finally came up with a solution.
It's more complex than your's, but it doesn't have any fudge factor that I know
of. I have to describe it in words; if you can put it into an equation, kudos
;-) (I'm really tired and the ol' brain is fizzling out...)

1) Choose a camera position; it can be anywhere. (So can the object.)

2) Get the bounding-box coordinates of the object-- the farthest and nearest
corner locations, whatever they happen to be.

3) find vlength from camera to nearest bounding-box corner. Call it L-1

4) find vlength from camera to farthest B-B corner. Call it L-2

5) L-1 / L-2 = S   This will be somewhere between 0.0 and 1.0-- it depends on
how far your object is from the camera. The farher apart, the larger this will
be.

6)  Then, (1.0 - S) = T

7) Using T, change your spherical color_map's original 0.0-to-1.0 index values
to a more 'squased' version, closer to the outer spherical 'surface'. (And don't
scale it up yet.)

     [0.0 BLUE] // outer radius of spherical pattern
     [.5*T WHITE]
     [T  RED ]  // what used to be the center point of the pattern; now father
                // out toward edge

8) Now scale-up the spherical pattern by L-2. That *should* put the outer
edge of the BLUE at or near the object's farthest bounding-box corner; and RED
should begin at or neat the closer corner.

CAVEAT: No guarantees are implied... :-P

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