how about making pigment transparency dynamic based on the distance the ray
travels through the object, or are fogs intended for this function?

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xoxos <nomail@nomail> wrote:
> how about making pigment transparency dynamic based on the distance the ray
> travels through the object, or are fogs intended for this function?

Use fade_power, fade_distance and fade_color in the 'interior' block of
the object.

-- 
                                                          - Warp

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> how about making pigment transparency dynamic based on the distance the ray
> travels through the object, or are fogs intended for this function?
>
>
The easiest way, and fastest to render, is to use fading (fade_distance, 
fade_power and fade_color) as Warp stated.

This will not realy obscure what is behind the object, just tint it.

You can also fill the object with some scattering media. It will 
significantly increase the render time, but will allow you to have 
non-uniform absorbtion. To enable an object to contain media, you need 
to add "hollow" to that object.

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Alain wrote:

> To enable an object to contain media, you need 
> to add "hollow" to that object.

This has always struck me as somewhat strange. I think it would
be reasonable to have container objects (those that actually specify
use of media in their own interior) hollow by default.

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Alain <kua### [at] videotronca> wrote:
> The easiest way, and fastest to render, is to use fading (fade_distance,
> fade_power and fade_color) as Warp stated.
>
> This will not realy obscure what is behind the object, just tint it.
>
> You can also fill the object with some scattering media. It will
> significantly increase the render time, but will allow you to have
> non-uniform absorbtion. To enable an object to contain media, you need
> to add "hollow" to that object.


It sounds easy to use...
I didn't use these features.

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> Alain <kua### [at] videotronca> wrote:
>> The easiest way, and fastest to render, is to use fading (fade_distance,
>> fade_power and fade_color) as Warp stated.
>>
>> This will not realy obscure what is behind the object, just tint it.
>>
>> You can also fill the object with some scattering media. It will
>> significantly increase the render time, but will allow you to have
>> non-uniform absorbtion. To enable an object to contain media, you need
>> to add "hollow" to that object.
>
>
> It sounds easy to use...
> I didn't use these features.
>
>

Easy to use, yes.

Be warned that if you scale an object using those features it's aspect 
WILL change as the distance a ray travel through the object will change.

For the media, it's the fine tuning that can be tricky.
The defaults for media are:
sampling method: 3 (adaptive sampling)
intervals: 1 (MUST be kept at that value, larger values hugely increase 
the rendering time)
samples: 10 (must be at least 3 for the adaptive feature to work)
samples use ONLY 1 value (the two values syntax is for sampling method 1 
and 2). If a second value is provided, it will be silently ignored.

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Alain <kua### [at] videotronca> wrote:
> Easy to use, yes.
>
> Be warned that if you scale an object using those features it's aspect
> WILL change as the distance a ray travel through the object will change.
>
> For the media, it's the fine tuning that can be tricky.
> The defaults for media are:
> sampling method: 3 (adaptive sampling)
> intervals: 1 (MUST be kept at that value, larger values hugely increase
> the rendering time)
> samples: 10 (must be at least 3 for the adaptive feature to work)
> samples use ONLY 1 value (the two values syntax is for sampling method 1
> and 2). If a second value is provided, it will be silently ignored.

Uh...thanks for this old hand response. I am just fascinate with POV-Ray for
some time, and can study it a while.

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