I've got what I believe should be a working POV macro for Perlin noise (2D
only, currently). After fixing a number of typographical errors, it now
crashes whenever I try to use it.

I was wondering if someone would be willing to look at the code for me.

If you're up to it, either post here, or write me at kil### [at] homecom.

Thanks a ton,
Lonnie

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Lonnie Ezell wrote:
> 
> I've got what I believe should be a working POV macro for Perlin noise (2D
> only, currently). After fixing a number of typographical errors, it now
> crashes whenever I try to use it.
> 
> I was wondering if someone would be willing to look at the code for me.
> 
> If you're up to it, either post here, or write me at kil### [at] homecom.

[whispered voice] If you post it, they will come!

Seriously, post the code in povray.text.scene-file and I'm sure someone
will have a looksie.
-- 
Francois Labreque | Unfortunately, there's no such thing as a snooze
    flabreque     | button on a cat who wants breakfast.
        @         |      - Unattributed quote from rec.humor.funny
   videotron.ca

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In article <3a5a5aec@news.povray.org>, "Lonnie Ezell" 
<kil### [at] homecom> wrote:

> I've got what I believe should be a working POV macro for Perlin noise (2D
> only, currently). After fixing a number of typographical errors, it now
> crashes whenever I try to use it.

Well, not an answer to your quesion, but MegaPOV has the noise3d() 
function available in ordinary scene code. This is the same function 
that is used for the bozo pattern, and may do what you want.
MegaPOV is available here: http://nathan.kopp.com/patched.htm


> I was wondering if someone would be willing to look at the code for me.

You'll have to post it for anyone to do that... ;-)

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

<><

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Lonnie Ezell wrote:
> 
> I've got what I believe should be a working POV macro for Perlin noise (2D
> only, currently). After fixing a number of typographical errors, it now
> crashes whenever I try to use it.
> 
> I was wondering if someone would be willing to look at the code for me.
> 
> If you're up to it, either post here, or write me at kil### [at] homecom.
> 
> Thanks a ton,
> Lonnie

Well, I got it parsing after some modifications, but it doesn't seem to
produce correct output. I've no time to examine it more closely, but
seems like macro ED_NOISE_Rand_2D doesn't produce what it should be (see
below).
I made following changes in 8D_noise.inc:
line 82:
   ( ( (rand(ED_NOISE_RandArray[octave])*m_x) + (
(rand(ED_NOISE_RandArray[octave]) * m_y) ) ) / 2.0 )   
(you had x and y instead of m_x and m_y, so returned value was vector
instead of float and parser chocked on it. But seems like you have
semantical problem there as well, as you multiply random value with
input value (evaluation point) and thus returned value is not between 0
and 1, but grows with x or y.  Additionally, code in Elias homepage
assumes, that generated value is between -1 and 1, so if you add
different octaves together, then some of them actually decrease total
value. I'd suggest to work with this generator and get it working
correctly, everything else will come afterwards...

line 98: "sides" is keyword in MegaPov, so if you use MegaPov or its
derivate, then change this name.
Macro ED_NOISE_Noise_2D should return ED_total (line 153) instead of
total.
additionally, lines 146 and 147 miss the terminating semicolon.

I don't understand though, why your POVRay crashed on it. Which version
do you use?

HTH,
Vahur

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I'm using 3.1g. I just uninstalled, downloaded the latest and reinstalled.

Still no luck. It crashes on parsing, although it doesn't on some clock
macros I'm working on.

It says it has in invalid Page Fault in PVENGINE.

Might need to reinstall Windows. (95 OSR2)

Thanks for your help, I'll make the changes when I get this working again,
since I can't get it to run to debug the crazy thing.

Anyways, thanks for looking at it...
Lonnie

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Lonnie Ezell wrote:
> 
> I've got what I believe should be a working POV macro for Perlin noise (2D
> only, currently). After fixing a number of typographical errors, it now
> crashes whenever I try to use it.
> 
> I was wondering if someone would be willing to look at the code for me.
> 
> If you're up to it, either post here, or write me at kil### [at] homecom.

I have just posted a modified version of your Perlin 
Noise code to povray-text.scene-files:

news://news.povray.org/3A679CD3.CB5F8C27%40online.no


I have tried to keep things simple and in one file only.

Some modifications has also been done to the macros so
that they only modifies arguments that are passed them.

I'll have to agree with Vahur that the main problem 
seems to be your ED_NOISE_Rand_2D macro. It needs to 
be rewritten.

But I'm not sure if the built in noise3d() is suitable 
for this purpose (i.e. to be used within ED_NOISE_Rand_2D).

It might be that your ED_Noise_Init macro also needs to 
be rewritten.


-- 
Best regards,

Tor Olav

mailto:tor### [at] hotmailcom
http://www.crosswinds.net/~tok/tokrays.html

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