is there *any* interest in being able to use
".df3" media density files as input for the
dat_3d_3, dat_2d_1, (etc) SuperPatch
functions?
Like, are there many (any?) of these files
laying around looking for some purpose in life?

I just 'fixed' my copy of MegaPov to accept them
and they seem to work fine now, but is there a
*reason* to put this functionality into MegaPov?
I mean, its not like one is likely to make df3 files
for this purpose since the other formats are quite
adequate as far as I can see, except for the single
fact that .df3 contain their own sample dimensions,
while to use the files already accepted by the dat_?D_?
functions, one has to specify the sampling dimensions,
but that does not seem like much of a big deal to me.

Post a reply to this message

I think we've got some duplicate work  going on here. Smellenbergh wrote
some code so that libraries, such as the dat_3d stuff, can be compiled
directly into MegaPov (which is incorporated into my current working code).
If you want to submit any modifications to the isosurface code (such as the
ability to read d3f files), let him know.  I do think it would be good for
POV to accept 3d data in a single consistent format for both media and
isosurfaces.

-Nathan


david sharp <dsh### [at] interportnet> wrote...
> is there *any* interest in being able to use
> ".df3" media density files as input for the
> dat_3d_3, dat_2d_1, (etc) SuperPatch
> functions?
> Like, are there many (any?) of these files
> laying around looking for some purpose in life?
>
> I just 'fixed' my copy of MegaPov to accept them
> and they seem to work fine now, but is there a
> *reason* to put this functionality into MegaPov?
> I mean, its not like one is likely to make df3 files
> for this purpose since the other formats are quite
> adequate as far as I can see, except for the single
> fact that .df3 contain their own sample dimensions,
> while to use the files already accepted by the dat_?D_?
> functions, one has to specify the sampling dimensions,
> but that does not seem like much of a big deal to me.
>
>

Post a reply to this message

david sharp wrote:

>is there *any* interest in being able to use
>".df3" media density files as input for the
>dat_3d_3, dat_2d_1, (etc) SuperPatch
>functions?

I don't know. Would there be a difference in result wether you use a .df3 in 
dat_3d_3 or use it in a pigment based isosurface? If so, what is the 
difference?

Ingo

-- 
Photography: http://members.home.nl/ingoogni/
Pov-Ray    : http://members.home.nl/seed7/

Post a reply to this message

What I would want to be able to do is to create df3 density maps
inside povray itself, without external files. Just like it's possible to
create a heightfield without an external file in megapov.
  Is this already possible in megapov?

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

Post a reply to this message

ingo  wrote
> david sharp wrote:
>
> >is there *any* interest in being able to use
> >".df3" media density files as input for the
> >dat_3d_3, dat_2d_1, (etc) SuperPatch
> >functions?
>
> I don't know. Would there be a difference in result wether you use a .df3
in
> dat_3d_3 or use it in a pigment based isosurface? If so, what is the
> difference?

there should not be much difference except that .df3 has a maximum
of 8 bit precision in its values, while you can get up to 64 bits
precision with a couple of the dat_3d_3 file formats.

Post a reply to this message

Nieminen Juha <war### [at] punarastascstutfi> wrote in message
news:385a1d52@news.povray.org...
>   What I would want to be able to do is to create df3 density maps
> inside povray itself, without external files. Just like it's possible to
> create a heightfield without an external file in megapov.
>   Is this already possible in megapov?

I am not sure what you mean, but with MegaPov or SuperPatch
I think you can use an isosurface function as a density, as in:

#declare densfn=function{x^3+y-z^2}

sphere{0,.5
 texture{
   pigment{rgbt 1}
 }
 interior{
     media{
       emission 1
       density{
         function{densfn}
         color_map{
            [0     rgb<1,1,1>]
            [.1    rgb<0,0,1>]
            [1     rgb<0,0,0>]
         }
       }

    }
 }
 hollow
}

(I am *not* saying that this snippet is good example!
It is just to show syntax)

Post a reply to this message

No, I really mean df3 density data, not a function (unless the function can
read an array...).

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

Post a reply to this message

Nieminen Juha wrote:
> No, I really mean df3 density data, not a function (unless the function
can
> read an array...).

So you are asking if one can create data for dat_3d_3
inside the scene file? Like maybe using a #macro ?
So far as I can tell, the function{} can't use arrays or #macros.
I would like to use data arrays that are more complex than is
practical to get from what fits in a function{} declaration.
For example, all kinds weird recursive stuff, integral transforms,
fractals, etc etc. POV script language being more complex than what
is accepted inside function{}.
What I have been playing with  is using the POV-Ray scene
script language to #fopen a data file and fill that file with data,
#fclose, then somewhere below that in the scene file just call
dat_3d_3 on the just created data file. It works OK, but it is not
very efficient, since that data "should" just be put into an array
in memory which dat_3d_ "should" be able to read.
Is that what you mean?

Post a reply to this message