I am trying to remove all infinite objects from my source, but one object
keeps showing as infinite (found by commenting the code) which is a large
sphere that the entire scene and camera are inside.  I have tried to use
bounded_by statements but it still shows infinite.   Anybody know what I am
doing wrong?  I am trying to eliminate all the infinite objects to assist in
using the photon feature in Megapov.



#declare Globe =
object

   sphere {<0,0,0> , 2000.0
      texture {
         pigment {
            image_map {
               tga "img0053.tga"
               map_type 1
               interpolate 4
            }
          }
          finish {ambient 1 }
      }
      hollow
    //  bounded_by {sphere{<0,0,0>, 2000}}
   }
}


object {Globe
  bounded_by {sphere{<0,0,0>, 2000}}
}

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"Patrick Dugan" <pat### [at] usticom> wrote in message
news:3a00767a$1@news.povray.org...

I haven't tried it, but could it be that your bounding sphere is the same
radius as the globe - a coincident surface type problem?

Try making the bounding sphere a unit bigger? Also, shouldn't your globe be
"inverse"?

WARNING - I'm usually wrong.

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On Wed, 1 Nov 2000 21:59:32 -0000, Tom Melly wrote...
> I haven't tried it, but could it be that your bounding sphere is the same
> radius as the globe - a coincident surface type problem?
> 
> Try making the bounding sphere a unit bigger? Also, shouldn't your globe be
> "inverse"?
> 
> WARNING - I'm usually wrong.

You may be here, 'cos I think  the bounding sphere is commented out in 
the code he posted there...

Oh, and I have no idea what the problem may be, since I tried a similar 
scene through Moray and MeagPOV 0.6a, and nothing I did could get MegaPOV 
to tell me the sphere was infinite...  

<grasping at straws>
Maybe it's something to do with the image mapped texture?
</grasping at straws>

Bye for now,
     Jamie.

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"Jamie Davison" <jam### [at] dh70qdu-netcom> wrote in message
news:MPG.146aa3cb1a864ad2989830@news.povray.org...
> >
> > WARNING - I'm usually wrong.
>
> You may be here, 'cos I think  the bounding sphere is commented out in
> the code he posted there...
>

I don't think so - one version is commented out, but he's declared his globe
as an object and bound that.

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Patrick Dugan <pat### [at] usticom> wrote:
> I am trying to remove all infinite objects from my source, but one object
> keeps showing as infinite (found by commenting the code) which is a large
> sphere that the entire scene and camera are inside.  I have tried to use
> bounded_by statements but it still shows infinite.   Anybody know what I
am
> doing wrong?  I am trying to eliminate all the infinite objects to assist
in
> using the photon feature in Megapov.

POV-Ray will often report large spheres as infinite objects (after a quick
test, it seems anything over 1356 units in radius).  I'm not sure what (if
any) effect this has on the rendering, as the size you have is certainly
well below the upper visibility limit.  If the infinity of the sphere is
causing problems, a fix might be to reduce the radius to 1355 units...

Post a reply to this message

In article <3a00920c@news.povray.org>, "Tom Melly" <tom### [at] tomandlucouk> 
wrote:

> I haven't tried it, but could it be that your bounding sphere is the same
> radius as the globe - a coincident surface type problem?
> Try making the bounding sphere a unit bigger?

Bounding shapes don't check depth, they simply test whether an 
intersection is possible or not. Kind of a visibility test. It might be 
possible for a problem to occur at the edges if a ray happens to just 
graze the sphere(something which is practically impossible and unlikely 
to produce a visible artifact if it does), but in the center of the 
bounding sphere it wouldn't be a problem.
In this case, a bounding sphere that surrounds the camera, lights, and 
any transparent/reflective objects should as well as a sphere 
surrounding the whole sphere.


> Also, shouldn't your globe be "inverse"?

Or hollow. Inverse would make more sense, but neither is actually 
necessary unless you are using media or fog.

-- 
Christopher James Huff
Personal: chr### [at] maccom, http://homepage.mac.com/chrishuff/
TAG: chr### [at] tagpovrayorg, http://tag.povray.org/

<><

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Patrick Dugan wrote in message <3a00767a$1@news.povray.org>...
>I am trying to remove all infinite objects from my source, but one object
>keeps showing as infinite (found by commenting the code) which is a large
>sphere that the entire scene and camera are inside.  I have tried to use
>bounded_by statements but it still shows infinite.   Anybody know what I am
>doing wrong?  I am trying to eliminate all the infinite objects to assist
in
>using the photon feature in Megapov.


Any object where the volume of the bounding box is larger than 2.0x10^10 is
considered to be an infinite object.

Mark

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"Patrick Dugan" <pat### [at] usticom> wrote in message
news:3a00767a$1@news.povray.org...
> I am trying to remove all infinite objects from my source, but one object
> keeps showing as infinite (found by commenting the code) which is a large
> sphere that the entire scene and camera are inside.  I have tried to use

Just out of curiousity, is there any point in bounding a sphere in this
context?

Post a reply to this message

Chris Huff <chr### [at] maccom> wrote:
: Or hollow. Inverse would make more sense, but neither is actually 
: necessary unless you are using media or fog.

  I think there's a third case where there's difference between an inverted
and non-inverted sky sphere: If it has (for some reason) ior.

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

Post a reply to this message

Patrick Dugan <pat### [at] usticom> wrote:
: which is a large
: sphere that the entire scene and camera are inside.

  This is what's making povray to treat the sphere as infinite.
  And for a good reason. You will get no benefits from making povray to
believe that it's not infinite (povray has to test for the sphere in each
ray anyways).

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

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