Hi,

  I have a question about the bounded_by statement or better the warning
that I get when I use it.
When I included a bounded_by statement I got this warning:

h4_rastep.pov:117: warning: Unnecessary bounding object removed.

However, povray works well and is about 20 times faster than without the
bounded_by statement.
Therefore I assume it is not removing the 'unnecessary bounding object'
after all.
Should I simply ignore this warning or is there something I can do about
it.
(Sorry, I am still using POV-Ray 3.02)
Here is some of the input:

 quadric { <  3.5476,  6.8899,  7.7222 >, <  1.3424,  1.4042,  0.0504 >
                 <  0.0000,  0.0000,  0.0000 >, -0.0065
    translate < -0.4672, -0.0366, -0.0209 >
    bounded_by {sphere {<-0.4672, -0.0366, -0.0209>,  0.0520 } }
    texture { pigment { rgb < 0.7906, 0.7906, 0.7906 > }
    finish { SPHE_FINISH }
}

Thanks,

   Lothar Esser

------------------------------------------------------------------
Dr. Lothar Esser
UT Southwestern Medical Center Dallas
5323 Harry Hines Blvd.
Dallas Texas 75235-9050
E-mail : ess### [at] chopswmededu
------------------------------------------------------------------

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On Wed, 03 Nov 1999 11:52:29 -0600, Lothar Esser wrote:
>Should I simply ignore this warning or is there something I can do about
>it.

You can specify -UR on the command line to turn off unnecessary bounds 
removal but it's a bug that POV tries to remove it in the first place,
and it might be considered a bug that it doesn't entirely succeed.
I've crossposted this message to .bugreports, with followups back to
..general.

POV will remove the bounds on all objects except unions, intersections,
merges, polys, and texts.  Obviously quadrics and quartics should be in
this list, too, unless they were among the handful of quadrics that 
POV can bound automatically (ellipsoids and axis-aligned cones, cylinders, 
paraboloids, hyperboloids, etc.)

The reason it still renders faster even after the bounding volume is 
removed is that the bounding box of the bounding volume gets assigned
to another variable in the quadric object [1] before the bounding 
volume gets nuked [2].  This bounding volume remains because the 
"computed" volume is "larger."  Thus, just destroying the bounding 
object doesn't entirely remove the effects of the bounded_by statement.

[1] POV computes bbox at the end of Parse_Object_Mods
[2] in Link_To_Frame, called by Parse_Frame after the object is completely 
    parsed
-- 
These are my opinions.  I do NOT speak for the POV-Team.
The superpatch: http://www2.fwi.com/~parkerr/superpatch/
My other stuff: http://www2.fwi.com/~parkerr/traces.html

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In povray.general Ron Parker <ron### [at] povrayorg> wrote:
: it's a bug that POV tries to remove it in the first place,

  Or at least a design flaw. If I specify a bounding box, that means that
I really want to use that bounding box and don't want povray to remove it.

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

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On 4 Nov 1999 04:27:18 -0500, Nieminen Juha wrote:
>In povray.general Ron Parker <ron### [at] povrayorg> wrote:
>: it's a bug that POV tries to remove it in the first place,
>
>  Or at least a design flaw. If I specify a bounding box, that means that
>I really want to use that bounding box and don't want povray to remove it.

In that case, specify -UR.  I don't consider that a design flaw, as it can
be useful in removing unnecessary ray-intersection tests.  My point was that 
even if you want POV to remove unnecessary bounds, it shouldn't try to remove 
a manual bounding object for an object it can't find a better bound for.

-- 
These are my opinions.  I do NOT speak for the POV-Team.
The superpatch: http://www2.fwi.com/~parkerr/superpatch/
My other stuff: http://www2.fwi.com/~parkerr/traces.html

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Ron Parker wrote:

> On Wed, 03 Nov 1999 11:52:29 -0600, Lothar Esser wrote:
> >Should I simply ignore this warning or is there something I can do about
> >it.
>
> You can specify -UR on the command line to turn off unnecessary bounds
> removal but it's a bug that POV tries to remove it in the first place,
> and it might be considered a bug that it doesn't entirely succeed.
> I've crossposted this message to .bugreports, with followups back to
> ..general.
>
> [1] POV computes bbox at the end of Parse_Object_Mods
> [2] in Link_To_Frame, called by Parse_Frame after the object is completely
>     parsed
> --
>
    Thanks for the excellent comment. BTW, if this behavior is a glitch, then
it is also
present in POV-Ray 3.1. (I tested my code in POV-Ray  3.1 (SGI) but with the
+MV3 option
to indicate that it is old-style input ).
Thanks again.

>
>    Lothar Esser
>
> ------------------------------------------------------------------
> Dr. Lothar Esser
> UT Southwestern Medical Center Dallas
> 5323 Harry Hines Blvd.
> Dallas Texas 75235-9050
> E-mail : ess### [at] chopswmededu
> ------------------------------------------------------------------

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On Fri, 05 Nov 1999 09:30:54 -0600, Lothar Esser wrote:
>    Thanks for the excellent comment. BTW, if this behavior is a glitch, then
>it is also
>present in POV-Ray 3.1. (I tested my code in POV-Ray  3.1 (SGI) but with the
>+MV3 option
>to indicate that it is old-style input ).

Thanks; I failed to mention that my observations were based on the 3.1g 
code.

-- 
These are my opinions.  I do NOT speak for the POV-Team.
The superpatch: http://www2.fwi.com/~parkerr/superpatch/
My other stuff: http://www2.fwi.com/~parkerr/traces.html

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