I recall a discussion sometime last year about a bug in the random number
generator
that resulted in 'flat' areas in the bozo and spotted patterns.

I've just run across and example and my question is: Is there a
workaround/solution for this. I'm working on a scene where I need most of
the objects covered with soot and the flat areas really look bad. The
texture I'm working with is :

 pigment {
  spotted
  color_map {
   [0.0 rgbt<0.2,0.2,0.2,0.2>]
   [0.8 rgbt<0.3,0.3,0.3,0.4>]
   [0.85 rgbt<0.4,0.4,0.4,0.5>]
   [1.0 rgbt<0.5,0.5,0.5,0.6>]
  }
  turbulence 0.4
  translate x*5
  scale 0.1
 }

Thanks for any help

Gail
*******************************************************************
* gsh### [at] monotixcoza              * ERROR: COFFEE.COM not found  *
* http://www.rucus.ru.ac.za/~gail/ * Insert cup and press any key *
*******************************************************************
* Definition of an upgrade: Take the old bugs out, put new ones in*
*******************************************************************

Post a reply to this message

In article <38743b32@news.povray.org>, "Gail Shaw" 
<gsh### [at] monotixcoza> wrote:

> I recall a discussion sometime last year about a bug in the random number
> generator
> that resulted in 'flat' areas in the bozo and spotted patterns.
> 
> I've just run across and example and my question is: Is there a
> workaround/solution for this.

There are no workarounds that I know of. Apparently the problem can be 
fixed, but it would change the pattern. It would still look like bozo or 
spotted(minus the big flat areas), but scenes rendered with the new 
version would appear slightly different.
This doesn't matter for the vast majority of scenes(only for those where 
a specific portion of the pattern was focused on), and I think the 
benefits outweigh this slight incompatibility. But I don't know how to 
fix it, I just know that there is a fix.

-- 
Chris Huff
e-mail: chr### [at] yahoocom
Web page: http://chrishuff.dhs.org/

Post a reply to this message

Chris Huff wrote in message ...

>There are no workarounds that I know of. Apparently the problem can be
>fixed, but it would change the pattern. It would still look like bozo or
>spotted(minus the big flat areas), but scenes rendered with the new
>version would appear slightly different.
>This doesn't matter for the vast majority of scenes(only for those where
>a specific portion of the pattern was focused on), and I think the
>benefits outweigh this slight incompatibility. But I don't know how to
>fix it, I just know that there is a fix.
>


Guess I'll have to wait until someone gets around to fixing it.  For my
current
image, it turns out that wrinkles looks better, and it doesn't seem to be
affected
by the flat area bug.

Gail
*******************************************************************
* gsh### [at] monotixcoza              * ERROR: COFFEE.COM not found  *
* http://www.rucus.ru.ac.za/~gail/ * Insert cup and press any key *
*******************************************************************
* Definition of an upgrade: Take the old bugs out, put new ones in*
*******************************************************************

Post a reply to this message

Wasn't sure exactly which way you were arguing.

I would clarify:
The benefits [of changing the unorthodoxy noise definition would] outweight
this slight incompatibility.

Chris Huff wrote:

> This doesn't matter for the vast majority of scenes(only for those where
> a specific portion of the pattern was focused on), and I think the
> benefits outweigh this slight incompatibility. But I don't know how to
> fix it, I just know that there is a fix.
>
> --
> Chris Huff
> e-mail: chr### [at] yahoocom
> Web page: http://chrishuff.dhs.org/

Post a reply to this message

In article <387A0962.EA59760B@my-dejanews.com>, 
gre### [at] my-dejanewscom wrote:

> Wasn't sure exactly which way you were arguing.
> 
> I would clarify:
> The benefits [of changing the unorthodoxy noise definition would] 
> outweight this slight incompatibility.

Yes, that is what I meant. It would also allow using bozo for height 
fields, which it currently is not useful for(because of the plateus).
The only place I can think of which could be a problem is with height 
fields generated with POV using a pattern based on the noise 
function(like wrinkles or several others, or anything with turbulence).
And this only applies in some of those cases.

-- 
Chris Huff
e-mail: chr### [at] yahoocom
Web page: http://chrishuff.dhs.org/

Post a reply to this message

All you have to do is fix it, and toss in a "version" thingy to get it to
work like it used to. Simple as that.

Post a reply to this message