Oops, my mistake.  Wasn't thinking "post-process" entirely.
I got it in my mind this was a type of thing where
you specify color mapping to apply the effect.  Akin to HF and such things
where the color value makes the change.
What I'm confused about is about the contribution the scene itself makes.
That only gets affected it appears and does not do the actual effect?
If I'm not confusing you now, what I see when looking at it seems
to be using a normal on a plane having the 'spotted' pattern and a ior in
just those few places instead of throughout.  I realize this isn't the case.

Bob

"Chris Huff" <chr### [at] yahoocom> wrote in message
news:chrishuff_99-E27878.11505828042000@news.povray.org...
| In article <3909babb@news.povray.org>, "Bob Hughes"
| <per### [at] aolcom?subject=PoV-News:> wrote:
|
| > Is this on a separate plane between the camera and scene?
|
| I'm not sure what you mean...it is a post_process filter, not a part of
| the scene, it is applied to the image itself.
| What it does is evaluate the the pigment as though the upper-left corner
| is <0,0,0> and the lower right is <1,1,0>.(that should probably be
| changed to <0,1,0> and <1,0,0> though, to make image_maps easier to use)
|
| --
| Christopher James Huff - Personal e-mail: chr### [at] yahoocom
| TAG(Technical Assistance Group) e-mail: chr### [at] tagpovrayorg
| Personal Web page: http://chrishuff.dhs.org/
| TAG Web page: http://tag.povray.org/

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