POV-Ray : Newsgroups : povray.beta-test : texture transparency and radiosity Server Time
30 Jul 2024 02:19:45 EDT (-0400)
  texture transparency and radiosity (Message 1 to 7 of 7)  
From: Dean
Subject: texture transparency and radiosity
Date: 6 Feb 2002 14:59:12
Message: <3C6188A6.B40A8CDE@twoalpha.net>
I have an object that I am  using a .gif texture for.  the reason for
this is to use the transparency of selected palette colors.  Is there a
way to have radiosity travel through the transparent colors?  Currently
I have been trying to use low intensity area lights to try and fake the
effect and the result is always much too bright.  I had the same
difficulty in V3.1 so I would not call it a bug per se.

Perhaps there would be something in programming to make this work
without too much difficulty..

any ideas would be helpful  thanks

Dean Johnson


Post a reply to this message

From: Christoph Hormann
Subject: Re: texture transparency and radiosity
Date: 6 Feb 2002 16:28:29
Message: <3C619FF2.268EFD34@gmx.de>
Dean wrote:
> 
> I have an object that I am  using a .gif texture for.  the reason for
> this is to use the transparency of selected palette colors.  Is there a
> way to have radiosity travel through the transparent colors?  Currently
> I have been trying to use low intensity area lights to try and fake the
> effect and the result is always much too bright.  I had the same
> difficulty in V3.1 so I would not call it a bug per se.

I have never had any problems with radiosity and transparent surfaces, if
you think there is something not working as it should, post a short
sample.

Christoph

-- 
POV-Ray tutorials, IsoWood include,                 
TransSkin and more: http://www.tu-bs.de/~y0013390/  
Last updated 06 Feb. 2002 _____./\/^>_*_<^\/\.______


Post a reply to this message

From: Dean
Subject: Re: texture transparency and radiosity
Date: 6 Feb 2002 22:14:23
Message: <3C61EE21.D5E6D02E@twoalpha.net>
Christoph,

A transparent surface like glass for example works fine.  What I am talking
about is a .GIF texture with an assigned color to be transparent, such as:

#declare mypigment =
pigment
{
 image_map
 {
   gif "lattice.gif"
  transmit 21, 0
 filter   21, 1}
 scale <1.000000, 1.000000, 1.000000>
 }

where color 21 is the transparent color that I want radiosity to go through.
Light sources will go through the transparent color but radiosity will not.
I will make a scene tonight to post to the binary section a bit later.

Dean


Christoph Hormann wrote:

> Dean wrote:
> >
> > I have an object that I am  using a .gif texture for.  the reason for
> > this is to use the transparency of selected palette colors.  Is there a
> > way to have radiosity travel through the transparent colors?  Currently
> > I have been trying to use low intensity area lights to try and fake the
> > effect and the result is always much too bright.  I had the same
> > difficulty in V3.1 so I would not call it a bug per se.
>
> I have never had any problems with radiosity and transparent surfaces, if
> you think there is something not working as it should, post a short
> sample.
>
> Christoph
>
> --
> POV-Ray tutorials, IsoWood include,
> TransSkin and more: http://www.tu-bs.de/~y0013390/
> Last updated 06 Feb. 2002 _____./\/^>_*_<^\/\.______


Post a reply to this message

From: Peter Popov
Subject: Re: texture transparency and radiosity
Date: 7 Feb 2002 05:57:08
Message: <esl46ucothumunlcm3shmuu6asq18ioddl@4ax.com>
>where color 21 is the transparent color that I want radiosity to go through.
>Light sources will go through the transparent color but radiosity will not.
>I will make a scene tonight to post to the binary section a bit later.

That's interesting. Have you tried increasing the recursion level?
Have you tried using hollow (not that it makes sense to, but that's
what beta-testing is for :) )? Try to pinpoint it if it is a bug, is
what I mean.


Peter Popov ICQ : 15002700
Personal e-mail : pet### [at] vipbg
TAG      e-mail : pet### [at] tagpovrayorg


Post a reply to this message

From: Tor Olav Kristensen
Subject: Re: texture transparency and radiosity
Date: 8 Feb 2002 16:49:58
Message: <3C644760.AADD997F@hotmail.com>
Dean wrote:
> 
> I have an object that I am  using a .gif texture for.  the reason for
> this is to use the transparency of selected palette colors.  Is there a
> way to have radiosity travel through the transparent colors?  Currently
> I have been trying to use low intensity area lights to try and fake the
> effect and the result is always much too bright.  I had the same
> difficulty in V3.1 so I would not call it a bug per se.
> 
> Perhaps there would be something in programming to make this work
> without too much difficulty..
> 
> any ideas would be helpful  thanks

I have a vague memory about removal
of GIF support from POV-Ray...

Can someone please refresh my memory ?


Tor Olav


Post a reply to this message

From: Thorsten Froehlich
Subject: Re: texture transparency and radiosity
Date: 8 Feb 2002 17:05:07
Message: <3c644b93$1@news.povray.org>
In article <3C644760.AADD997F@hotmail.com> , Tor Olav Kristensen 
<tor### [at] hotmailcom>  wrote:

> I have a vague memory about removal
> of GIF support from POV-Ray...
>
> Can someone please refresh my memory ?

Not in any official version.

    Thorsten

____________________________________________________
Thorsten Froehlich, Duisburg, Germany
e-mail: tho### [at] trfde

Visit POV-Ray on the web: http://mac.povray.org


Post a reply to this message

From: Dean
Subject: Re: texture transparency and radiosity
Date: 8 Feb 2002 20:08:42
Message: <3C6476B3.4CEB45F@twoalpha.net>
Guys,

I re-loaded a few 3.1 scripts that had given me problems this way in the past.
POV 3.5 has made a liar out of me, sorry for the alarm.  I think I am
interpreting a different problem now NOT related to the transparent color since,
coincidentally, that is a similar  appearance.  Sometimes it works and sometimes
it fails.

One other thing I did was to cut holes in a mesh2 object using a CSG
difference.  The messages said this is not allowed but the effect was
successful.  I find this as a useful operation and see no reason for making it
illegal. Please don't fix it ;).

The only thing that did was the not happen was the material didn't fill the
intersection like it often does for pure csg differences due to the surface
nature of the mesh2 object.  Perhaps this created leaks in the mesh and caused
the lighting problems for me.

Thanks for your suggestions and advice here.

Dean


Post a reply to this message

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