Hi.
I have been running an egg crate pattern of two different IOR regions unioned
together.  It seems to nearly work, but it seems to max out the trace level
"256/256" when I up the frequency of the pattern.  This probably makes sense
since there will be more internal reflections depending on the freq. of my
pattern.  But, is there anyway to increase the max_trace_level to a value
larger than 256? Maybe there is a patch/hack of the source code?
Also, I notice that sometimes when the max trace level gets blown out I get
either a white or black spot.  I would prefer black, can I choose; what does
the difference correspond to?

Thanks,
Mike

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"Mike" <win### [at] hotmailcom> wrote in message 
news:web.49b5eb09eed67712cb45af7a0@news.povray.org...
> Hi.
> I have been running an egg crate pattern of two different IOR regions 
> unioned
> together.  It seems to nearly work, but it seems to max out the trace 
> level
> "256/256" when I up the frequency of the pattern.  This probably makes 
> sense
> since there will be more internal reflections depending on the freq. of my
> pattern.  But, is there anyway to increase the max_trace_level to a value
> larger than 256? Maybe there is a patch/hack of the source code?
> Also, I notice that sometimes when the max trace level gets blown out I 
> get
> either a white or black spot.  I would prefer black, can I choose; what 
> does
> the difference correspond to?

I'm not absolutely sure, but I believe it gets the background color.

cu!
-- 
#macro G(b,e)b+(e-b)*C/50#end#macro _(b,e,k,l)#local C=0;#while(C<50)
sphere{G(b,e)+3*z.1pigment{rgb G(k,l)}finish{ambient 1}}#local C=C+1;
#end#end _(y-x,y,x,x+y)_(y,-x-y,x+y,y)_(-x-y,-y,y,y+z)_(-y,y,y+z,x+y)
_(0x+y.5+y/2x)_(0x-y.5+y/2x)            // ZK http://www.povplace.com

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"Mike" <win### [at] hotmailcom> wrote:
> Also, I notice that sometimes when the max trace level gets blown out I get
> either a white or black spot.  I would prefer black, can I choose; what does
> the difference correspond to?

I have been told that you can control this with the background color. Never
tested it myself though.

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"clipka" <nomail@nomail> wrote:
> "Mike" <win### [at] hotmailcom> wrote:
> > Also, I notice that sometimes when the max trace level gets blown out I get
> > either a white or black spot.  I would prefer black, can I choose; what does
> > the difference correspond to?
>
> I have been told that you can control this with the background color. Never
> tested it myself though.

I just tried it:
_________________________________________________________

global_settings
{  assumed_gamma 1
   max_trace_level 5
}

background { rgb <0, 1, 1> } //bright cyan background ;-)

camera
{  location <-3, 2.5, -10>
   look_at <-0.3, 1.2, 0>
   angle 22
}

light_source { <-1, 3, -2> * 10000, rgb 1 }

plane { y, 0 pigment { rgb 1 } }

union
{  #declare I = 0;
   #while (I < 5)
      box { <-1, 0, I>, <1, 2, I + 0.5> }
      #declare I = I + 1;
   #end
   pigment { rgbf <1, 0.8, 0.6, 1> }
}
_________________________________________________________

It doesn't seem to work that way, at least not with my version (the backwards
vintage 2006 3.6.1c.icl8.win32).

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"Mike" <win### [at] hotmailcom> wrote:
> I have been running an egg crate pattern of two different IOR regions unioned
> together.  It seems to nearly work, but it seems to max out the trace level
> "256/256" when I up the frequency of the pattern.  This probably makes sense
> since there will be more internal reflections depending on the freq. of my
> pattern.  But, is there anyway to increase the max_trace_level to a value
> larger than 256? Maybe there is a patch/hack of the source code?

Just came across the answer to your first original question:

This is limited by the constant MAX_TRACE_LEVEL_LIMIT, defined in
configbackend.h; its only purpose seems to be to provide for a "sanity check"
of the max_trace_level setting, so basically it should be possible to pick any
other aribitrary value like, say, 1024, or remove the check altogether.
However, there will be *some* limit to it imposed by the memory available, and
POV will probably crach if it reaches this limit. It will also affect render
time, of course.

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"Cousin Ricky" <ric### [at] yahoocom> wrote:
> I just tried it:

Just took the time to have a look at the source code: It does indeed set the
color to a hard-coded <0,0,0> when hitting max_trace_level.

Post a reply to this message

"clipka" <nomail@nomail> wrote:
> Just took the time to have a look at the source code: It does indeed set the
> color to a hard-coded <0,0,0> when hitting max_trace_level.

Do you think that using the background color or sky_sphere pigment would be a
worthwhile suggestion for versions 3.7 and 4.0?

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"Cousin Ricky" <ric### [at] yahoocom> wrote:
> "clipka" <nomail@nomail> wrote:
> > Just took the time to have a look at the source code: It does indeed set the
> > color to a hard-coded <0,0,0> when hitting max_trace_level.
>
> Do you think that using the background color or sky_sphere pigment would be a
> worthwhile suggestion for versions 3.7 and 4.0?

I think it would be, yes.

Or, maybe even better, a max_trace_color.

Best if it could be specified on a per-texture basis.

Penultimate if it could be specified separately for reflection and refraction.

Then again, I guess in most cases a global max_trace_color would perfectly
suffice, and it would not waste too much memory.

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clipka nous illumina en ce 2009-03-10 12:37 -->
> "Mike" <win### [at] hotmailcom> wrote:
>> Also, I notice that sometimes when the max trace level gets blown out I get
>> either a white or black spot.  I would prefer black, can I choose; what does
>> the difference correspond to?
> 
> I have been told that you can control this with the background color. Never
> tested it myself though.
> 
> 
> 
Just tested.
With 3.6.1 windows: returns BLACK!
With 3.7 beta windows: increased the number of box to 12 and NO max_trace problem.

-- 
Alain
-------------------------------------------------
Believe those who are seeking the truth; doubt those who find it.

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Cousin Ricky nous illumina en ce 2009-03-12 09:58 -->
> "clipka" <nomail@nomail> wrote:
>> Just took the time to have a look at the source code: It does indeed set the
>> color to a hard-coded <0,0,0> when hitting max_trace_level.
> 
> Do you think that using the background color or sky_sphere pigment would be a
> worthwhile suggestion for versions 3.7 and 4.0?
> 
> 
> 
Non isue for plain transparency with 3.7, it just traces trough. Adding interior 
with fade_color also goes trough.
Adding some reflection and I get some black, but mixed with the reflected color 
in most places. Same result with both 3.6 and 3.7.
Returns black IF there is an interior with some ior.


-- 
Alain
-------------------------------------------------
A critic is a man who knows the way, but can't drive the car.

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