POV-Ray : Newsgroups : povray.binaries.images : Example of potential pattern use with emitting media. : Re: Example of potential pattern use with emitting media. Server Time
30 Apr 2024 10:03:23 EDT (-0400)
  Re: Example of potential pattern use with emitting media.  
From: William F Pokorny
Date: 12 Oct 2016 03:45:38
Message: <57fdea22$1@news.povray.org>
On 10/11/2016 03:30 PM, omniverse wrote:
> William F Pokorny <ano### [at] anonymousorg> wrote:
>> Experimenting with the new potential pattern and emitting media. In this
>> image both the media and container are blob based.
>>
>> Existing media boundary issues remain, requiring some care in set up.
>
> Tried it now too after seeing this.
> Something going on at edges that I noticed during animation, maybe like you.
> Only slightly visible as a tiny red curve along the surface near middle-right,
> where the blob overlaps itself.
> I didn't try 'frequency' yet.
>
> This media uses mostly emission 0.4 and a little absorption 0.1, along with
> scattering type 1, amount 0.6. Simple density_map of red green and blue, all
> values of 1.
>
I've never tried to use emitting with scattering. I do find myself using 
absorption at a value about equal to the emission value to keep the 
emitting media under some control where the ray path gets long in the 
media - and so brighter. Such brightening is realistic for an emitting 
media/gas to a point.

In an animation I suspect it is changing path length(s) through emitting 
media that you are seeing more than blob container fringe, speckling, 
effects. Especially as it looks to me like you are using some focal blur 
which acts like strong AA with respect to all sorts of speckles and noise.

I went with multiple density based medias with set emission/absorption 
colors which I then mixed at particular locations by using different 
set-color blob components to get additional colors. In other words, 
where white is seen there are really three overlapping medias of Red 
Green and Blue. The containing blob for all the medias was constructed 
to contain the blobs of each of the set-color medias.

Bill P.


Post a reply to this message

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