> Just follow up the thread. I gave a clear description.
> The problem is i am looking for a good method to simulate this "foggy milk
> glass effect" without adding too much complexity. Maybe it is not possible
> but as long there are specialists I can ask them, right?
> I don't have a specific problem like artefacts or error messages or
> whatever. I'm just looking for solutions.
> 
> Thanks and regards,
> SY

You know.. Isn't it funny when a week after having the idea of subsurface scattering
simulation shot down as not needed because you can use media someone comes
along with a problem that can't be solved without 'serious' problems using only media.
This is exactly the kind of situation that I was talking about on that thread, though
I
can't seem to remember which one... lol It has been brought up on quite a few
occations. Earliest I could find was Aug 31 2001, but my mail reader won't pull, it up
and the http site doesn't give message headers... :p) No one has tried to do it yet as
far as I know and unfortunately I have trouble wrapping my mind around the other
math used in raytracing, so a patch for it is beyond me. :p

It would however probably do exactly what you need.

The paper on it is at http://www-graphics.stanford.edu/~henrik/papers/bssrdf/

This being probably the 30th time someone has posted it. ;) lol

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Umm... Dummy me.. Didn't think to look at the link name. lol

One thread is in pov.general #17855

Another thread starts in povray.advanced-users #16814

I still haven't found the one I posted too. :p

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Patrick Elliott wrote:
> 
> [...]
> 
> You know.. Isn't it funny when a week after having the idea of subsurface scattering
> simulation shot down as not needed because you can use media someone comes
> along with a problem that can't be solved without 'serious' problems using only
media.

To make it short, this kind of problem can't be solved with subsurface
scattering techniques either, the methods used for this are subject to the
same restrictions as scattering media.

Christoph

-- 
POV-Ray tutorials, IsoWood include,                 
TransSkin and more: http://www.tu-bs.de/~y0013390/  
Last updated 21 Feb. 2002 _____./\/^>_*_<^\/\.______

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> Not everyone reads messages online; some of us download the entire group
and
> read it offline.  We don't necessarily get a choice of which messages to
> download.

I know and therefore things like size filters exist. But I'll stop this now
since it is not my point of interest and this discussion will not lead to
anywhere.

However, thank you very much for your valuable hints and explanations. I
didn't know the special role of the 2-dimensional primitives like triangles
and their relatives in terms of interiors.
I'm sorry about the direct e-mail instead of the newsgroup post. This
happens to me at least once a week since I use too many different but
similar OS, PC's and installed software. Currently I have to use 3 of them
the hole day.... *g*

best regards
SY

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> You know.. Isn't it funny when a week after having the idea of subsurface
scattering

Thank you for your interesting link.
Unfortunately I am not talking about subsurface scattering. I need a think
which is like thick fog but blurres the background heavily so that no
contours come through unless they are very very close to the surface.
Additionally it should emit light when lit from the background.
All this (beside blurring) matches good on scattering media. The only
problem I have is, that the object is very thin. It is so thin that I
currently modelled it by using a mesh/triangles. To make it realistic it
must stay very thin (in reality approx. 1/10 to 1/8 mm). Having a scattering
media in such a small object forces me to make it very, very thick to be
visible at all. However, this blows up my PC's processing capacity so I
decided not to use it.
Maybe it will come up again when I model thicker objects. But up to now I'll
use filtering on the texture as it was up to now.
Due to the explanations of Ron I could make it run and it was quite
realistic. Unfortunately the interior doesn't work on triangles of meshes,
just on unions of triangles which would increase memory usage and slow down
rendering.

 > This being probably the 30th time someone has posted it. ;) lol

Sorry, still 29 times since the subject was just unluckily chosen. Sorry.
regards
SY

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> Due to the explanations of Ron I could make it run and it was quite
> realistic. Unfortunately the interior doesn't work on triangles of meshes,
> just on unions of triangles which would increase memory usage and slow down
> rendering.

It does work on the interiors of meshes; it just doesn't make any sense for
individual triangles in meshes to have separate interiors.

-- 
#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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> It does work on the interiors of meshes; it just doesn't make any sense
for
> individual triangles in meshes to have separate interiors.

but for some of the triangles. Just ALL or NONE is less usable than a way to
define a GROUP within a mesh. Why should have a mesh a homogenous interior
regardless of it's structure?

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In article <1103_1014761637@selliot>,
 Patrick Elliott <sel### [at] rrazcom> wrote:

> You know.. Isn't it funny when a week after having the idea of 
> subsurface scattering simulation shot down as not needed because you 
> can use media someone comes along with a problem that can't be solved 
> without 'serious' problems using only media.

But it can be solved with media, without serious problems. Exactly how 
to do this has been explained many times in this thread.

-- 
Christopher James Huff <chr### [at] maccom>
POV-Ray TAG e-mail: chr### [at] tagpovrayorg
TAG web site: http://tag.povray.org/

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In article <3c7cf5cf@news.povray.org>,


> but for some of the triangles. Just ALL or NONE is less usable than a way to
> define a GROUP within a mesh. Why should have a mesh a homogenous interior
> regardless of it's structure?

Because it is a single object, and thus only has one interior.
But you are only restricted to a single interior, it does not have to be 
homogenous. Media can have its density vary according to a pattern. The 
thing that doesn't make any sense would be for individual triangles of a 
mesh to have their own interiors. This has been explained many times, 
and is for fairly obvious reasons, I don't know why you don't understand 
it.
If different parts of your object are composed of different materials, 
you should probably be using a union of several meshes.

-- 
Christopher James Huff <chr### [at] maccom>
POV-Ray TAG e-mail: chr### [at] tagpovrayorg
TAG web site: http://tag.povray.org/

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> and is for fairly obvious reasons, I don't know why you don't understand
> it.
> If different parts of your object are composed of different materials,
> you should probably be using a union of several meshes.

Just because you can't imagine an object whose inner structure is
defined/influenced by it's outer shape it doesn't mean that I don't
understand the limitations implemented in the code.

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