I'm trying to create a static noise effect, like when your TV seems to fail.
I've allready tried MegaPOV's noise-pigment (monochromic) but the result
still isn't what I'm looking for, can anybody give me some advise?
Thanks

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iceqb nous apporta ses lumieres en ce 2005-11-14 15:32:
> I'm trying to create a static noise effect, like when your TV seems to fail.
> I've allready tried MegaPOV's noise-pigment (monochromic) but the result
> still isn't what I'm looking for, can anybody give me some advise?
> Thanks
> 
> 
You may try a cells pattern scaled relatively small and using a relatively sharp
colour_map.
Something like:
pigment{cells colour_map{[0.3 rgb 0][0.7 rgb 1]} scale 0.01}
Adjust the colour_map and scale to your needs.
-- 
Alain
-------------------------------------------------
'Honesty is the best policy, but insanity is a better defense'

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Alain <ele### [at] netscapenet> wrote:
> You may try a cells pattern scaled relatively small and using a relatively sharp
colour_map.
> Something like:
> pigment{cells colour_map{[0.3 rgb 0][0.7 rgb 1]} scale 0.01}
> Adjust the colour_map and scale to your needs.
> --
> Alain
> -------------------------------------------------
> 'Honesty is the best policy, but insanity is a better defense'

thanks, i'll try that, can i also use cells in media, or is it strictly a
pigment and normal-pattern?

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iceqb <web.43790d9160c7a1428323aad0@news.povray.org> Monday 14 of November
2005 23:20

> thanks, i'll try that, can i also use cells in media, or is it strictly a
> pigment and normal-pattern?

Hmm, I _think_ the goal is to remember that TV texture is discreet with
limited resolution of about 700x500 pixels, while normal POVray pigments
have almost "infinite accuaraycy".

Perhaps you shold created image texture, hmm I forgot the syntax (someone
can remind me?) but it was like

pigment 700,500 {
  bozo ...
  scale ...
}


-- 

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iceqb wrote:

> I'm trying to create a static noise effect, like when your TV seems to fail.
> I've allready tried MegaPOV's noise-pigment (monochromic) but the result
> still isn't what I'm looking for, can anybody give me some advise?
> Thanks

I simply use a bumps pattern, scaled down so taht it looks like snow on 
the tv screen.  A color map color_map { [.4 rgb 0][.6 rgb 1] } will work 
fine.

Make sure you translate the pattern with the clock, in a direction 
perpendicular to the TV screen, so that the snow appears to randomly 
change over time.

Regards,
John

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Raf256 <spa### [at] raf256cominvalid> wrote:
> iceqb <web.43790d9160c7a1428323aad0@news.povray.org> Monday 14 of November
> 2005 23:20
>
> Hmm, I _think_ the goal is to remember that TV texture is discreet with
> limited resolution of about 700x500 pixels, while normal POVray pigments
> have almost "infinite accuaraycy".
>
> Perhaps you shold created image texture, hmm I forgot the syntax (someone
> can remind me?) but it was like
>
> pigment 700,500 {
>   bozo ...
>   scale ...
> }
>
>
> --


Thanks for the tip, but I'm actually trying to achieve a realistic
light-emission from the tv, it's supposed to be the only light_source in
the scene. I thought about a light_source behind a transparenc map, but
that didn't work out. So I'm using or a high ambient value in combination
with radiosity, or emmisive media.

The suggestion about an image_map is good, because the texture didn't seem
quite wright.

thanks

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iceqb <web.4379e6ca60c7a1428323aad0@news.povray.org> Tuesday 15 of November
2005 14:46

> light-emission from the tv, it's supposed to be the only light_source in
> the scene. I thought about a light_source behind a transparenc map, but
> that didn't work out. So I'm using or a high ambient value in combination
> with radiosity, or emmisive media.

If You are using MegaPov (PovRAY + more-futures-patch) then keywords like 
no_image no_reflection no_radiosity will be helpfull

> The suggestion about an image_map is good, because the texture didn't seem
> quite wright.

-- 

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Raf256 <spa### [at] raf256cominvalid> wrote:
> iceqb <web.4379e6ca60c7a1428323aad0@news.povray.org> Tuesday 15 of November
> 2005 14:46
>
> If You are using MegaPov (PovRAY + more-futures-patch) then keywords like
> no_image no_reflection no_radiosity will be helpfull
>
> --


I mostly use MegaPOV instead of POV-Ray, thanks for the tip.

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iceqb nous apporta ses lumieres en ce 2005-11-14 17:20:
> Alain <ele### [at] netscapenet> wrote:
> 
>>You may try a cells pattern scaled relatively small and using a relatively sharp
colour_map.
>>Something like:
>>pigment{cells colour_map{[0.3 rgb 0][0.7 rgb 1]} scale 0.01}
>>Adjust the colour_map and scale to your needs.
>>--
>>Alain
>>-------------------------------------------------
>>'Honesty is the best policy, but insanity is a better defense'
> 
> 
> thanks, i'll try that, can i also use cells in media, or is it strictly a
> pigment and normal-pattern?
> 
> 
> 
> 
You can use it about anywhere: normal, pigment, texture, material, density.

-- 
Alain
-------------------------------------------------
Get a new car for your spouse. It'll be a great trade!

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