Hello!
Could someone tell me the exact formula, by wich POV-Ray calculates the color
values, when filter and transmit values are specified?
For example I give the color values: R(O), G(O), B(O), F(O), T(O) (let "O" mean
object here), and the colors of the backgrounc is R(B), G(B), B(B). Now, how
can I calculate, wich colours will the object show? Thank you very much for any
help.

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"Silverlight2009" <nomail@nomail> wrote:
> Hello!
> Could someone tell me the exact formula, by wich POV-Ray calculates the color
> values, when filter and transmit values are specified?
> For example I give the color values: R(O), G(O), B(O), F(O), T(O) (let "O" mean
> object here), and the colors of the backgrounc is R(B), G(B), B(B). Now, how
> can I calculate, wich colours will the object show? Thank you very much for any
> help.

Just had a look at it in the code. I think it's bogus regarding how the filter
is applied to the object, but anyway, here it is (effectively; the algorithm is
a bit more complex):

    R = R(O) * [ 1 - T(O) - F(O) * max(R(O),G(O),B(O)) ]
      + R(B) * [     T(O) + F(O) * R(O) ]

and similarly for the other color channels.

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