On Mon, 19 Nov 2001 14:05:38 +0100, "Thorsten Froehlich" <tho### [at] trfde>
wrote:
> > No, it only changes your max_gradient.  The reported found maximum gradient
> > value is still correct.

But I didn't wrote about 'found' value but about initial value!!!

ABX
--
#declare _=function(a,b,x){((a^2)+(b^2))^.5-x}#default {pigment{color rgb 1}}
union{plane{y,-3}plane{-x,-3}finish{reflection 1 ambient 0}}isosurface{ //ABX
function{_(x-2,y,1)|_((x+y)*.7,z,.1)|_((x+y+2)*.7,z,.1)|_(x/2+y*.8+1.5,z,.1)}
contained_by{box{<0,-3,-.1>,<3,0,.1>}}translate z*15finish{ambient 1}}//POV35

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Skiba <abx### [at] babilonorg>  wrote:

>> > No, it only changes your max_gradient.  The reported found maximum gradient
>> > value is still correct.
>
> But I didn't wrote about 'found' value but about initial value!!!

Yes, I say it "changes your max_gradient", so if it *changes* your
max_gradient, how can it report *your* max_gradient? - It cannot and thus it
will report the *changed* max_gradient!

Anyway, just take my word for it:  This has long ago been fixed for the
_next_ beta.

    Thorsten

____________________________________________________
Thorsten Froehlich, Duisburg, Germany
e-mail: tho### [at] trfde

Visit POV-Ray on the web: http://mac.povray.org

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Skiba <abx### [at] babilonorg>  wrote:

>> > No, it only changes your max_gradient.  The reported found maximum gradient
>> > value is still correct.
>
> But I didn't wrote about 'found' value but about initial value!!!

BTW, why do you try to convince me that it is a bug when I have already
*acknowledged* that it is a bug? (Rhetoric question only, no answer
expected!)  Somehow communication failed completely...

    Thorsten

____________________________________________________
Thorsten Froehlich, Duisburg, Germany
e-mail: tho### [at] trfde

Visit POV-Ray on the web: http://mac.povray.org

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On Mon, 19 Nov 2001 14:16:26 +0100, "Thorsten Froehlich" <tho### [at] trfde>
wrote:
> Yes, I say it "changes your max_gradient", so if it *changes* your
> max_gradient, how can it report *your* max_gradient?

Can't it be remembered in local variable? It can report isosurface line within
source. Why it can't remember initial value? It shows line and then says 'value
was set to ...'

> Anyway, just take my word for it:  This has long ago been fixed for the
> _next_ beta.

Ok. I don't like bothering so sorry for this long bothering :-)

ABX
--
#declare _=function(a,b,x){((a^2)+(b^2))^.5-x}#default {pigment{color rgb 1}}
union{plane{y,-3}plane{-x,-3}finish{reflection 1 ambient 0}}isosurface{ //ABX
function{_(x-2,y,1)|_((x+y)*.7,z,.1)|_((x+y+2)*.7,z,.1)|_(x/2+y*.8+1.5,z,.1)}
contained_by{box{<0,-3,-.1>,<3,0,.1>}}translate z*15finish{ambient 1}}//POV35

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On Mon, 19 Nov 2001 14:22:52 +0100, "Thorsten Froehlich" <tho### [at] trfde>
wrote:
> BTW, why do you try to convince me that it is a bug when I have already
> *acknowledged* that it is a bug?

Becouse I thought all the time you're talking about different thing.

> (Rhetoric question only, no answer expected!)

Please don't read  above answer ;-)

> Somehow communication failed completely...

The easiest explanation for me is my english
but I don't know if it is good enough :-(

Sorry again for bothering, really sorry.

ABX
--
#declare _=function(a,b,x){((a^2)+(b^2))^.5-x}#default {pigment{color rgb 1}}
union{plane{y,-3}plane{-x,-3}finish{reflection 1 ambient 0}}isosurface{ //ABX
function{_(x-2,y,1)|_((x+y)*.7,z,.1)|_((x+y+2)*.7,z,.1)|_(x/2+y*.8+1.5,z,.1)}
contained_by{box{<0,-3,-.1>,<3,0,.1>}}translate z*15finish{ambient 1}}//POV35

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Skiba <abx### [at] babilonorg>  wrote:

> Can't it be remembered in local variable?

Because it is a ***bug*that*it*changes*the*user*supplied*max_gradient***!!!
It was never supposed to change it the way it does and then output that as
the user supplied max_gradient!!!

> It can report isosurface line within
> source. Why it can't remember initial value? It shows line and then says
> 'value was set to ...'

It has nothing to do with the *algorithm*, but a ***bug*** in the
*implementation* of the algorithm.  This obviously has to be fixed by
changing the *implementation* of the algorithm, not by *changing* the
*algorithm* itself!!!  And as I said:  It *has* been fixed this way already,
so any suggestion on how to change the *algorithm* to fix it is completely
unnecessary because the *algorithm* is correct, only its *implementation* is
*not* correct in beta 7!!!

    Thorsten

____________________________________________________
Thorsten Froehlich, Duisburg, Germany
e-mail: tho### [at] trfde

Visit POV-Ray on the web: http://mac.povray.org

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Skiba <abx### [at] babilonorg>  wrote:

> The easiest explanation for me is my english
> but I don't know if it is good enough :-(

Try reading more English and using it actively whenever you a chance.  It
really helps!

> Sorry again for bothering, really sorry.

No problem.

    Thorsten

____________________________________________________
Thorsten Froehlich, Duisburg, Germany
e-mail: tho### [at] trfde

Visit POV-Ray on the web: http://mac.povray.org

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: I don't like bothering but there is nothing about difference between typed value
: and outputed value. in that thread :-(

  Really? Did you actually read the whole thread? More precisely, this
article of mine:

From war### [at] tagpovrayorg Mon Nov 19 16:05:26 2001
Message-ID: <3be0175a@news.povray.org>
From: Warp <war### [at] tagpovrayorg>
Subject: Re: Isosurfaces *much* slower in beta 7?
Newsgroups: povray.beta-test

Thorsten Froehlich <tho### [at] trfde> wrote:
: * Warp: Do a sync (get change 1235) to try it.

  Ok, I did it, and there clearly is a difference.
  I tested with this small example:

#include "functions.inc"

camera { location -z*5 look_at 0 angle 35 }
light_source { <100,200,-300>, 1 }

isosurface
{ function { x^2+y^2+z^2-(1-.2*f_noise3d(x*8,y*8,z*8)) }
  contained_by { sphere { 0,1 } }
  max_gradient 2
  evaluate 1,10,.99
  pigment { rgb x } finish { specular .5 }
}


  The older version (ie. beta7) rendered that in 1 min 30 seconds in this
computer. The report was a bit odd:

Warning: The maximum gradient found was 3.555, but max_gradient of
the isosurface was set to 310.201. Adjust max_gradient to
get a faster rendering of the isosurface.

  The newer version renders the example above in 13 seconds, which is a clear
improvement.

Warning: The maximum gradient found was 3.477, but max_gradient of the
isosurface was set to 2.000. The isosurface may contain holes!
Adjust max_gradient to get a proper rendering of the isosurface.

  The max_gradient value of 3.477 seems to be correct. When I set max_gradient
to that, the isosurface renders ok.

  It seems that now 'evaluate' doesn't actually change the max_gradient, but
just calculates the correct one and reports it. The example above renders
equally whether or not the 'evaluate' is there.
  This behaviour seems logical to me.

-- 
#macro N(D,I)#if(I<6)cylinder{M()#local D[I]=div(D[I],104);M().5,2pigment{
rgb M()}}N(D,(D[I]>99?I:I+1))#end#end#macro M()<mod(D[I],13)-6,mod(div(D[I
],13),8)-3,10>#end blob{N(array[6]{11117333955,
7382340,3358,3900569407,970,4254934330},0)}//                     - Warp -

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Skiba <abx### [at] babilonorg>  wrote:

> I can't agree. When there are more then one isosurfaces simetimes initial
value
> is only way to recognize where founded value shuold be applied.

You do realize that it outputs the line number of the isosurface, don't you?
So there is absolutely no need to use the max_gradient to identify different
isosurfaces...

    Thorsten

____________________________________________________
Thorsten Froehlich, Duisburg, Germany
e-mail: tho### [at] trfde

Visit POV-Ray on the web: http://mac.povray.org

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On Mon, 19 Nov 2001 15:08:52 +0100, "Thorsten Froehlich" <tho### [at] trfde>
wrote:
> You do realize that it outputs the line number of the isosurface, don't you?

Yes, before I missed this.

> So there is absolutely no need to use the max_gradient to identify different
> isosurfaces...

Yes, I agree now. Congratulations of your patience :-)

ABX
--
#declare _=function(a,b,x){((a^2)+(b^2))^.5-x}#default {pigment{color rgb 1}}
union{plane{y,-3}plane{-x,-3}finish{reflection 1 ambient 0}}isosurface{ //ABX
function{_(x-2,y,1)|_((x+y)*.7,z,.1)|_((x+y+2)*.7,z,.1)|_(x/2+y*.8+1.5,z,.1)}
contained_by{box{<0,-3,-.1>,<3,0,.1>}}translate z*15finish{ambient 1}}//POV35

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