How does one specify the no_reflection option to a fog?
I have a white, reflective plane with an object above it.
In the background is a blue "wall" of fog (ground fog that is rotated).
The shadow of the object on the white plane appears blue because the 
plane is reflecting the blue fog "wall".
I want the shadow to be gray as opposed to blue.
I was advised in the irc.freenode.net #povray channel to use 
no_reflection, but povray 3.6.1 complains when trying to use this in the 
fog.
In addition, object { fog { ... no_reflection } } causes an error 
because fog is not an object, I guess... which is probably why it 
doesn't accept the no_reflection option either.

I was thinking of having a second, transparent plane slightly above
the white, reflective plane that did not transmit blue light... but
this would have the unintended consequence of filtering the
blue light from the reflection of the object hoving above the plane too.

Any suggestions?

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mntorrent nous apporta ses lumieres ainsi en ce 2004-09-24 18:42... :

> How does one specify the no_reflection option to a fog?
> I have a white, reflective plane with an object above it.
> In the background is a blue "wall" of fog (ground fog that is rotated).
> The shadow of the object on the white plane appears blue because the 
> plane is reflecting the blue fog "wall".
> I want the shadow to be gray as opposed to blue.
> I was advised in the irc.freenode.net #povray channel to use 
> no_reflection, but povray 3.6.1 complains when trying to use this in 
> the fog.
> In addition, object { fog { ... no_reflection } } causes an error 
> because fog is not an object, I guess... which is probably why it 
> doesn't accept the no_reflection option either.
>
> I was thinking of having a second, transparent plane slightly above
> the white, reflective plane that did not transmit blue light... but
> this would have the unintended consequence of filtering the
> blue light from the reflection of the object hoving above the plane too.
>
> Any suggestions?

You can replace your fog by a media filled box, the box been given the 
no_reflection. The render time may be longer.

Alain

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You could try adding the metallic keyword to the reflection of the 
plane, like that: reflection { yourvalues metallic }
This will color the reflections in the color of the plane's pigment...

HTH,
Florian
-- 
The man who strikes first admits that his
ideas have given out. (Chinese Proverb)
[------------ http://www.torfbold.com - POV-Ray gallery ------------]

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I ended up adding another plane perpedicular to the floor
several units behind the object but very much in front of the
blue fog wall.
This plane is not rendered and does not cast shadows, but it
is reflected by other surfaces.

The definition of this plane is

plane
{
      locationv-look_atv, -6
      texture { pigment{color rgbft <0,0,1,1,1> } }
      no_image  // DON'T ACTUALLY RENDER THE PLANE
      no_shadow // DON'T EVEN LET THE INVISIBLE PLANE CAST SHADOWS
      // no_reflection // WE ARE GOING TO LET THE PLANE BE REFLECTED
}

The relfected pigment of this plane seemed to nearly cancel out
the blueness of the fog on the surface of the white plane...somewhat.




mntorrent wrote:
> How does one specify the no_reflection option to a fog?
> I have a white, reflective plane with an object above it.
> In the background is a blue "wall" of fog (ground fog that is rotated).
> The shadow of the object on the white plane appears blue because the 
> plane is reflecting the blue fog "wall".
> I want the shadow to be gray as opposed to blue.
> I was advised in the irc.freenode.net #povray channel to use 
> no_reflection, but povray 3.6.1 complains when trying to use this in the 
> fog.
> In addition, object { fog { ... no_reflection } } causes an error 
> because fog is not an object, I guess... which is probably why it 
> doesn't accept the no_reflection option either.
> 
> I was thinking of having a second, transparent plane slightly above
> the white, reflective plane that did not transmit blue light... but
> this would have the unintended consequence of filtering the
> blue light from the reflection of the object hoving above the plane too.
> 
> Any suggestions?

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