POV-Ray : Newsgroups : povray.general : Alpha and background Server Time
30 Jul 2024 18:12:41 EDT (-0400)
  Alpha and background (Message 1 to 10 of 10)  
From: Lilith
Subject: Alpha and background
Date: 28 May 2008 17:00:35
Message: <1ihr34tffecjbhdp73d79mqqpgdvoril7k@4ax.com>
I'm doing some rendering using the +FN +AU for transparency.  I'm not
sure yet if this will even work the way I want it to but.... I prefer
that there be no back ground whatsoever, so hopefully only the
rendered image will appear in an application I'm working on.  What do
I need to set as the background color, if any?  I believe I'd managed
to generate an image with only the checkered field showing behind the
object in the render window before but I don't seem to recall how I
managed it.

-- 
Lilith


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From: Stephen
Subject: Re: Alpha and background
Date: 28 May 2008 17:21:29
Message: <o4jr34l36lt496skfl3kf721ijk8suolce@4ax.com>
On Wed, 28 May 2008 16:00:35 -0500, Lilith <lil### [at] dcccdedu> wrote:

> What do
>I need to set as the background color, if any?

In the documents
3.3.2.2  Background

e.g for a black background

background { color rgb <0.000,0.000,0.000> }

-- 

Regards
     Stephen


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From: Lilith
Subject: Re: Alpha and background
Date: 28 May 2008 17:49:47
Message: <8qkr34df9t3489m1b1gqbd5mdonn65i63p@4ax.com>
On Wed, 28 May 2008 22:20:58 +0100, Stephen <mcavoysAT@aolDOTcom>
wrote:

>On Wed, 28 May 2008 16:00:35 -0500, Lilith <lil### [at] dcccdedu> wrote:
>
>> What do
>>I need to set as the background color, if any?
>
>In the documents
>3.3.2.2  Background
>
>e.g for a black background
>
>background { color rgb <0.000,0.000,0.000> }

I'm not sure you understand.  I need the background to ultimately be
transparent in the rendered PNG file.

-- 
Lilith


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From: Zeger Knaepen
Subject: Re: Alpha and background
Date: 28 May 2008 17:54:14
Message: <483dd486$1@news.povray.org>
"Lilith" <lil### [at] dcccdedu> wrote in message 
news:8qkr34df9t3489m1b1gqbd5mdonn65i63p@4ax.com...
> On Wed, 28 May 2008 22:20:58 +0100, Stephen <mcavoysAT@aolDOTcom>
> wrote:
>
>>On Wed, 28 May 2008 16:00:35 -0500, Lilith <lil### [at] dcccdedu> wrote:
>>
>>> What do
>>>I need to set as the background color, if any?
>>
>>In the documents
>>3.3.2.2  Background
>>
>>e.g for a black background
>>
>>background { color rgb <0.000,0.000,0.000> }
>
> I'm not sure you understand.  I need the background to ultimately be
> transparent in the rendered PNG file.

with +ua it will be, no matter what your background-color is

cu!
-- 
#macro G(b,e)b+(e-b)*C/50#end#macro _(b,e,k,l)#local C=0;#while(C<50)
sphere{G(b,e)+3*z.1pigment{rgb G(k,l)}finish{ambient 1}}#local C=C+1;
#end#end _(y-x,y,x,x+y)_(y,-x-y,x+y,y)_(-x-y,-y,y,y+z)_(-y,y,y+z,x+y)
_(0x+y.5+y/2x)_(0x-y.5+y/2x)            // ZK http://www.povplace.com


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From: stbenge
Subject: Re: Alpha and background
Date: 28 May 2008 18:39:56
Message: <483ddf3c$1@news.povray.org>
Lilith wrote:
> On Wed, 28 May 2008 22:20:58 +0100, Stephen <mcavoysAT@aolDOTcom>
> wrote:
>> e.g for a black background
>>
>> background { color rgb <0.000,0.000,0.000> }
> 
> I'm not sure you understand.  I need the background to ultimately be
> transparent in the rendered PNG file.
> 

Stephen's suggestion won't work if you are using the beta version of 
POV-Ray. You will have to explicitly add transparency to the background, 
like so:

background{ rgb 0 transmit 1}

Sam


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From: Warp
Subject: Re: Alpha and background
Date: 28 May 2008 19:40:51
Message: <483ded83@news.povray.org>
stbenge <stb### [at] hotmailcom> wrote:
> Stephen's suggestion won't work if you are using the beta version of 
> POV-Ray. You will have to explicitly add transparency to the background, 
> like so:

> background{ rgb 0 transmit 1}

  Did you actually test that it works like that?

-- 
                                                          - Warp


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From: Warp
Subject: Re: Alpha and background
Date: 28 May 2008 19:41:41
Message: <483dedb5@news.povray.org>
Lilith <lil### [at] dcccdedu> wrote:
> I'm doing some rendering using the +FN +AU for transparency.  I'm not
> sure yet if this will even work the way I want it to but....

  Just use those parameters (well, +ua, not +au). The background will
be transparent.

-- 
                                                          - Warp


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From: stbenge
Subject: Re: Alpha and background
Date: 28 May 2008 20:33:57
Message: <483df9f5$1@news.povray.org>
Warp wrote:
> stbenge <stb### [at] hotmailcom> wrote:
>> Stephen's suggestion won't work if you are using the beta version of 
>> POV-Ray. You will have to explicitly add transparency to the background, 
>> like so:
> 
>> background{ rgb 0 transmit 1}
> 
>   Did you actually test that it works like that?

Yes, I did. Why? +ua was also added to the command line.

These also work:

background{ 0 transmit 1}

background{ <0,0,0,0,1>}

Sam


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From: Warp
Subject: Re: Alpha and background
Date: 29 May 2008 04:47:12
Message: <483e6d90@news.povray.org>
stbenge <stb### [at] hotmailcom> wrote:
> Warp wrote:
> > stbenge <stb### [at] hotmailcom> wrote:
> >> Stephen's suggestion won't work if you are using the beta version of 
> >> POV-Ray. You will have to explicitly add transparency to the background, 
> >> like so:
> > 
> >> background{ rgb 0 transmit 1}
> > 
> >   Did you actually test that it works like that?

> Yes, I did. Why? +ua was also added to the command line.

  Ah, I missed that change in the changelog. Sorry.

-- 
                                                          - Warp


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From: Lilith
Subject: Re: Alpha and background
Date: 29 May 2008 16:37:41
Message: <av4u34h9i8b3bn3tlqbinoj01jpn4n4g5c@4ax.com>
On 28 May 2008 19:41:41 -0400, Warp <war### [at] tagpovrayorg> wrote:

>Lilith <lil### [at] dcccdedu> wrote:
>> I'm doing some rendering using the +FN +AU for transparency.  I'm not
>> sure yet if this will even work the way I want it to but....

>  Just use those parameters (well, +ua, not +au). The background will
>be transparent.

Achh!  There we go.  Brain f*rt I guess.

Many thanks.  You're now in my will.

-- 
Lilith


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