I know the lightwave about 0.75
micrometer gives the color <1,0,0>,
(at least I think so) the lightwave
0.54 gives color <0,1,0> and lightwave
0.42 gives color <0,0,1>, but I need a
formula that can calculate the color
for ANY (visible) lightwaves. The result
would be if I used the formula with a
clock function or similar it would give
a smooth color blend. The lightwaves
don't need to be in micrometer units.
I need this so I can improve the CD
texture I posted earlier.

thanks,

Rune S. Johansen
http://hjem.get2net.dk/rsj

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"Rune S. Johansen" wrote:
> 
> I know the lightwave about 0.75
> micrometer gives the color <1,0,0>,
> (at least I think so) the lightwave
> 0.54 gives color <0,1,0> and lightwave
> 0.42 gives color <0,0,1>, but I need a
> formula that can calculate the color
> for ANY (visible) lightwaves. The result
> would be if I used the formula with a
> clock function or similar it would give
> a smooth color blend. The lightwaves
> don't need to be in micrometer units.
> I need this so I can improve the CD
> texture I posted earlier.

I will soon release a set of macros that will do exactly that among many
other light and color related things. If you are impatient, you can go
to http://www.fourmilab.ch/netpbm/ .  The cietoppm code contains the
needed (C) functions, which you can translate to POV without too much
trouble.  Incidentally, www.fourmilab.ch is a cornucopia of useful,
quirky and fascinating things created by John Walker, the founder of
Autodesk.  For color science background info, I also suggest that you
visit the Poynton colour faq at
http://www.inforamp.net/~poynton/Poynton-colour.html .

Jerry Anning
cle### [at] dholcom

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Jerry Anning wrote:
>I will soon release a set of macros that will do exactly that among many
>other light and color related things.

That sounds great! Macros in POV-code I hope?

>If you are impatient, you can go
>to http://www.fourmilab.ch/netpbm/ .  The cietoppm code contains the
>needed (C) functions, which you can translate to POV without too much
>trouble.

I'm not sure about that. I havn't even seen any C-code before. :(

>Incidentally, www.fourmilab.ch is a cornucopia of useful,
>quirky and fascinating things created by John Walker, the founder of
>Autodesk.  For color science background info, I also suggest that you
>visit the Poynton colour faq at
>http://www.inforamp.net/~poynton/Poynton-colour.html .


It looked a bit complicated to me and I wasn't able to find the
exact information I needed.

>
>Jerry Anning
>cle### [at] dholcom

I'm looking forward to the macros.
Please mail me or the newsgroup when they are ready :)

Rune S. Johansen
http://hjem.get2net.dk/rsj

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