POV-Ray : Newsgroups : povray.advanced-users : Problem with alpha rendering Server Time
1 Nov 2024 17:21:32 EDT (-0400)
  Problem with alpha rendering (Message 1 to 4 of 4)  
From: Roy Schulz
Subject: Problem with alpha rendering
Date: 1 Aug 2001 05:00:36
Message: <3b67c534@news.povray.org>
I tried rendering in two layers (backgorund and foreground) for
post-processing reasons (blurring background). For the foreground I used the
command line switch +ua +fn to enable transparency output to PNG. But the
result was not as expected. Only rays that directly hit the background plane
were transparent and there are problems with CSG. Reflected rays or those
going through semi-transparent objects produced an opaque alpha.
In BMRT  the transparency corresponds to how much of the background plane is
shining through or being reflected or whatever. Is there a way to achieve
this in POV-Ray?

Roy


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From: Warp
Subject: Re: Problem with alpha rendering
Date: 1 Aug 2001 07:25:27
Message: <3b67e727@news.povray.org>
AFAIK the alpha channel feature in 3.1 was more or less experimental and
far from perfect.
  POV-Ray 3.5 will have a much better support.

-- 
#macro N(D,I)#if(I<6)cylinder{M()#local D[I]=div(D[I],104);M().5,2pigment{
rgb M()}}N(D,(D[I]>99?I:I+1))#end#end#macro M()<mod(D[I],13)-6,mod(div(D[I
],13),8)-3,10>#end blob{N(array[6]{11117333955,
7382340,3358,3900569407,970,4254934330},0)}//                     - Warp -


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From: Roy Schulz
Subject: Re: Problem with alpha rendering
Date: 1 Aug 2001 17:19:33
Message: <3b687265@news.povray.org>
Sounds promising. What is the current status of povray 3.5? The last message
on www.povray.org is from 1st Sep 2000.

Roy


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From: Ron Parker
Subject: Re: Problem with alpha rendering
Date: 1 Aug 2001 17:30:17
Message: <slrn9mgt7c.vcf.ron.parker@fwi.com>
On Wed, 1 Aug 2001 23:07:59 +0200, Roy Schulz wrote:
>Sounds promising. What is the current status of povray 3.5? The last message
>on www.povray.org is from 1st Sep 2000.

Whatever it says is the current official status.

-- 
#local R=<7084844682857967,0787982,826975826580>;#macro L(P)concat(#while(P)chr(
mod(P,100)),#local P=P/100;#end"")#end background{rgb 1}text{ttf L(R.x)L(R.y)0,0
translate<-.8,0,-1>}text{ttf L(R.x)L(R.z)0,0translate<-1.6,-.75,-1>}sphere{z/9e3
4/26/2001finish{reflection 1}}//ron.parker@povray.org My opinions, nobody else's


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