Also have a look at http://news.povray.org/povray.binaries.images/19254/
Code here: http://news.povray.org/povray.binaries.scene-files/19278/

--
#local j=text{ttf"arial""JRG".2,0}#local J=0;#while(J<10)#local R=0;#while
(R<2)#local G=0;#while(G<1)#if(inside(j<R,G.1>))object{j scale.025translate
<R-1G-J/20J/-40+2>pigment{rgb<9J>}}#debug"O"#else#debug" "#end#local G=G+
.025;#end#local R=R+.05;#debug"\n"#end#local J=J+1;#end// JRG

Home: http://digilander.iol.it/jrgpov  //New: Kitchen scene WIP

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Nice effect. You forgot the filtering, but otherwise looks good. I will try it with
my candle shape when I have some time.

--
#local j=text{ttf"arial""JRG".2,0}#local J=0;#while(J<10)#local R=0;#while
(R<2)#local G=0;#while(G<1)#if(inside(j<R,G.1>))object{j scale.025translate
<R-1G-J/20J/-40+2>pigment{rgb<9J>}}#debug"O"#else#debug" "#end#local G=G+
.025;#end#local R=R+.05;#debug"\n"#end#local J=J+1;#end// JRG

Home: http://digilander.iol.it/jrgpov  //New: Kitchen scene WIP

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In article <3c49ca75@news.povray.org>, "JRG" <jrg### [at] hotmailcom> 
wrote:

> Nice effect. You forgot the filtering, but otherwise looks good.

I didn't forget any filtering...

I very rarely use partially transparent textures. If I want something 
transparent or translucent, I use "rgbf 1" and use media (absorbing for 
clear objects, absorbing and scattering for translucent ones) or 
fade_color to color it. This gives the most realistic results: thin 
parts are nearly colorless. It is how things work in reality...a colored 
block of glass isn't a colored, infinitely thin surface that transmits 
light the same no matter how much glass it passes through.

-- 
 -- 
Christopher James Huff <chr### [at] maccom>

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>    // replace with "rgb 1" to see effect without translucence
>    texture {pigment {color rgb 1}}
                                           ^^^^
Ahem... ;)

--
#local j=text{ttf"arial""JRG".2,0}#local J=0;#while(J<10)#local R=0;#while
(R<2)#local G=0;#while(G<1)#if(inside(j<R,G.1>))object{j scale.025translate
<R-1G-J/20J/-40+2>pigment{rgb<9J>}}#debug"O"#else#debug" "#end#local G=G+
.025;#end#local R=R+.05;#debug"\n"#end#local J=J+1;#end// JRG

Home: http://digilander.iol.it/jrgpov  //New: Kitchen scene WIP

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The only program that seems to implement subsurface scatering not by a
fake seems to be finalrender a new plugin renderer for 3dsmax4.2.

I felt upon the van jensen paper some time ago, I have been really
impressed with the human skin he could obtain.

If POV would implement BSSRDF model it would clearly maintain it in
the top renderers... Whisfull thinking...





"Patrick Elliott" <sel### [at] rrazcom> wrote in message
news:1104_1011391405@selliot...
> On Fri, 18 Jan 2002 10:25:28 +0100, "Claude Mench"
<c.m### [at] adilinstrumentscom> wrote:
> > I just wanted to now if in all the unoficial
> > versions of pov there could be a version that
> > allow me to do theses two things:
> >
> >
> >     - SubSurface scaterring. Very nice effects possible with it.
>
> Someone else posted this link
 http://graphics.stanford.edu/~henrik/papers/bssrdf/ )
> reffering to an article on this and using it to make a lot of things look
more real. It can possibly
> be faked (though not in any eay fashion), but at this point I don't think
it is directly supported yet.
>
> Someone may create a patch for it once 3.5 is completed. I hope so at
least, since I have seen
> many posts on sites like www.renderosity.com and none of the programs they
use seem to
> support it, or at least they have never used it on any models. It would be
a very nice addition to
> POV, especially for organics where realism is dependant as much on fine
detail, as the way light
> normally interects with say human skin. You could probably tweak existing
features all you like
> and never end up with something that is truly accurate. But then I am no
where near as good
> as most of the other people that use POV all the time. ;)
>

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Claude Mench wrote:
> 
> The only program that seems to implement subsurface scatering not by a
> fake seems to be finalrender a new plugin renderer for 3dsmax4.2.
> 

It seems you have not completely understood this, 'real' subsurface
scattering with the model explained in the van Jensen paper is in fact
much more fake than participating media, of course it's much faster than
media without serious quality problems due to some neat approximations.

Christoph

-- 
Christoph Hormann <chr### [at] gmxde>
IsoWood include, radiosity tutorial, TransSkin and other 
things on: http://www.schunter.etc.tu-bs.de/~chris/

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On Mon, 21 Jan 2002 18:38:29 +0100, Christoph Hormann <chr### [at] gmxde> wrote:
> 
> 
> Claude Mench wrote:
> > 
> > The only program that seems to implement subsurface scatering not by a
> > fake seems to be finalrender a new plugin renderer for 3dsmax4.2.
> > 
> 
> It seems you have not completely understood this, 'real' subsurface
> scattering with the model explained in the van Jensen paper is in fact
> much more fake than participating media, of course it's much faster than
> media without serious quality problems due to some neat approximations.
> 
> Christoph
> 
> -- 
> Christoph Hormann <chr### [at] gmxde>
> IsoWood include, radiosity tutorial, TransSkin and other 
> things on: http://www.schunter.etc.tu-bs.de/~chris/

That may be true, but using media requires a number of things. Like a clear 'inside'
and
'outside' for object. In some circumstances, including using meshes, the method of
employing media could be probamatic at the very least. Not to mention that there is a
major difference between adding a single keywork like 'sub_scatter .5'  and fiddling
with
media settings, which I for one don't have a clue about. I want to be able to
realistically
model a human, but would definitely prefer not to have to spend 4 times longer trying
to
learn how to do it the hard way and getting a useful set of media to produce the
desired
effect, than I would just dropping in one or two keywords. I am not that good at
either
model buidling or the complexities of things like media. Nor being somewhat lazy am I
going to spend a lot of time playing with them to figure out how they work. Also for
those
that do 'need' it, for professional work, the extra time needed to tweak media and
render
can become expensive in terms of time needed to complete a project.

I could be wrong about it not being functionally possible in a mesh though, since I am
by no means an expert. ;)

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On Mon, 21 Jan 2002 22:16:22 GMT, Patrick Elliott wrote:
> 
> That may be true, but using media requires a number of things. Like a clear 'inside'
and
> 'outside' for object. 

This is a commonly held, though erroneous, belief.


-- 
#macro R(L P)sphere{L F}cylinder{L P F}#end#macro P(V)merge{R(z+a z)R(-z a-z)R(a
-z-z-z a+z)torus{1F clipped_by{plane{a 0}}}translate V}#end#macro Z(a F T)merge{
P(z+a)P(z-a)R(-z-z-x a)pigment{rgbf 1}hollow interior{media{emission 3-T}}}#end 
Z(-x-x.2x)camera{location z*-10rotate x*90normal{bumps.02scale.05}}

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In article <slr### [at] fwicom>,
 Ron Parker <ron### [at] povrayorg> wrote:

> This is a commonly held, though erroneous, belief.

Not so erroneous, unless you're talking about media without a container. 
As I understand it, you can use it in meshes, but it uses the number of 
intersections it has encountered to decide whether or not it is inside. 
Meshes with holes or other "odd" formations will not render as expected, 
because they don't have defined boundaries for the media sampling.

-- 
 -- 
Christopher James Huff <chr### [at] maccom>

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Christopher James Huff wrote:
> 
> Not so erroneous, unless you're talking about media without a container.
> As I understand it, you can use it in meshes, but it uses the number of
> intersections it has encountered to decide whether or not it is inside.
> Meshes with holes or other "odd" formations will not render as expected,
> because they don't have defined boundaries for the media sampling.

And 'real' subsurface scattering will have the same problems with such
meshes.  You simply can't expect 'odd' meshes to render correctly, in
addition other intrinsic problems like shadow line artefacts have their
influence too.  

Christoph

-- 
Christoph Hormann <chr### [at] gmxde>
IsoWood include, radiosity tutorial, TransSkin and other 
things on: http://www.schunter.etc.tu-bs.de/~chris/

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