POV-Ray : Newsgroups : povray.newusers : Use of radiosity negates effect of normals.... Server Time
30 Jul 2024 14:29:26 EDT (-0400)
  Use of radiosity negates effect of normals.... (Message 1 to 10 of 10)  
From: Greg M  Johnson
Subject: Use of radiosity negates effect of normals....
Date: 27 Mar 2004 22:03:17
Message: <40664075$1@news.povray.org>
...is this correct?   It's what I'm observing and goes along with what I
think I understand of the normal process-- just want to see if there's a
trick to get around it.


Post a reply to this message

From: Jaime Vives Piqueres
Subject: Re: Use of radiosity negates effect of normals....
Date: 28 Mar 2004 03:40:33
Message: <40668f81$1@news.povray.org>

> ...is this correct?   It's what I'm observing and goes along with what I
> think I understand of the normal process-- just want to see if there's a
> trick to get around it.
> 
> 

hmmm... radiosity{normal on}? :)

--
Jaime


Post a reply to this message

From: Christopher James Huff
Subject: Re: Use of radiosity negates effect of normals....
Date: 28 Mar 2004 11:56:11
Message: <cjameshuff-B028BD.11563428032004@news.povray.org>
In article <40664075$1@news.povray.org>,
 "Greg M. Johnson" <gregj;-)565### [at] aolcom> wrote:

> ...is this correct?   It's what I'm observing and goes along with what I
> think I understand of the normal process-- just want to see if there's a
> trick to get around it.

It doesn't negate normals, it just doesn't take them into account for 
radiosity lighting. Using "normal on" in the radiosity block will cause 
it to take the normals into account, giving slower but more accurate 
results.

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: <chr### [at] tagpovrayorg>
http://tag.povray.org/


Post a reply to this message

From: Severi Salminen
Subject: Re: Use of radiosity negates effect of normals....
Date: 28 Mar 2004 12:56:29
Message: <406711cd$1@news.povray.org>
Christopher James Huff wrote:

>>...is this correct?   It's what I'm observing and goes along with what I
>>think I understand of the normal process-- just want to see if there's a
>>trick to get around it.
> 
> 
> It doesn't negate normals, it just doesn't take them into account for 
> radiosity lighting. Using "normal on" in the radiosity block will cause 
> it to take the normals into account, giving slower but more accurate 
> results.

It is quite odd that they are turned off by default. I'd guess that 
people using normals would also like to see them regardless of the 
source of the light...

Severi S.


Post a reply to this message

From: Greg M  Johnson
Subject: Re: Use of radiosity negates effect of normals....
Date: 28 Mar 2004 22:50:04
Message: <40679cec$1@news.povray.org>
Okay but then does radiosity totally ignore both interior{fade_distance} and
media scattering?
I'm doing an architectural scene with a pool in it.  With radiosity on, the
pool bottom is completely white for a pigment {rgb 1} no matter how hight I
crank up the absorption, scattering, or fade distance negative exponent.




"Christopher James Huff" <cja### [at] earthlinknet> wrote in message
news:cjameshuff-B028BD.11563428032004@news.povray.org...
> In article <40664075$1@news.povray.org>,
>  "Greg M. Johnson" <gregj;-)565### [at] aolcom> wrote:
>
> > ...is this correct?   It's what I'm observing and goes along with what I
> > think I understand of the normal process-- just want to see if there's a
> > trick to get around it.
>
> It doesn't negate normals, it just doesn't take them into account for
> radiosity lighting. Using "normal on" in the radiosity block will cause
> it to take the normals into account, giving slower but more accurate
> results.
>
> -- 
> Christopher James Huff <cja### [at] earthlinknet>
> http://home.earthlink.net/~cjameshuff/
> POV-Ray TAG: <chr### [at] tagpovrayorg>
> http://tag.povray.org/


Post a reply to this message

From: Greg M  Johnson
Subject: Re: Use of radiosity negates effect of normals....
Date: 28 Mar 2004 22:55:41
Message: <40679e3d$1@news.povray.org>
Nevermind.  Media worked with hollow inserted in there.


Post a reply to this message

From: Christopher James Huff
Subject: Re: Use of radiosity negates effect of normals....
Date: 28 Mar 2004 23:05:22
Message: <cjameshuff-96E5C3.23054728032004@news.povray.org>
In article <40679cec$1@news.povray.org>,
 "Greg M. Johnson" <gregj;-)565### [at] aolcom> wrote:

> Okay but then does radiosity totally ignore both interior{fade_distance} and
> media scattering?
> I'm doing an architectural scene with a pool in it.  With radiosity on, the
> pool bottom is completely white for a pigment {rgb 1} no matter how hight I
> crank up the absorption, scattering, or fade distance negative exponent.

Media will work if "media on" is included in the radiosity block. Again, 
the default is off for speed. Interior attenuation should just work.

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: <chr### [at] tagpovrayorg>
http://tag.povray.org/


Post a reply to this message

From: Christopher James Huff
Subject: Re: Use of radiosity negates effect of normals....
Date: 28 Mar 2004 23:08:01
Message: <cjameshuff-11183E.23082628032004@news.povray.org>
In article <40679e3d$1@news.povray.org>,
 "Greg M. Johnson" <gregj;-)565### [at] aolcom> wrote:

> Nevermind.  Media worked with hollow inserted in there.

That must be the most common error with media. And it doesn't even need 
to be that way...it would be better if the interior of an object were 
always filled with the media specified for that object, and hollow only 
controlled whether external media could permeate the object.

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: <chr### [at] tagpovrayorg>
http://tag.povray.org/


Post a reply to this message

From: Christopher James Huff
Subject: Re: Use of radiosity negates effect of normals....
Date: 28 Mar 2004 23:10:14
Message: <cjameshuff-05157F.23103928032004@news.povray.org>
In article <406711cd$1@news.povray.org>,
 Severi Salminen <sev### [at] NOT_THISsibafi> wrote:

> It is quite odd that they are turned off by default. I'd guess that 
> people using normals would also like to see them regardless of the 
> source of the light...

Well, much of the time, the effects of normals + radiosity don't 
contribute much to the scene, and taking them into account makes things 
slower. As I recall, the earlier versions of radiosity never took 
normals into account, it was an added feature, so backwards 
compatibility may have been some part of the decision.

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: <chr### [at] tagpovrayorg>
http://tag.povray.org/


Post a reply to this message

From: Greg M  Johnson
Subject: Re: Use of radiosity negates effect of normals....
Date: 29 Mar 2004 22:04:12
Message: <4068e3ac$1@news.povray.org>
Golly, I wish all my questions based on failure to understand the docs
resulted in senior members saying that povray ought to work the way I think.
;-)


Post a reply to this message

Copyright 2003-2023 Persistence of Vision Raytracer Pty. Ltd.