In article <39609879@news.povray.org>, "Philippe Debar" 
<phi### [at] hotmailcom> wrote:

> Great. I suppose the corrected-map solution would be the quickest 
> (render-time-wise). For the function pattern, I suppose you mean 
> wrapping an "adapter" function around the noise/bumps.

I'm not sure what you mean...I meant something like this:

#declare oldBozo = function {max(0, min(1, noise3d(x,y,z)*1.5 - 0.25))}

This should be pretty close to the original bozo, though I was just 
guessing at the range(this one goes from -0.25 to 1.25 before clipping 
to create the plateaus, I don't know how far the original went). And it 
should also be quite fast...I rarely notice any speed difference with 
functions this simple.


> Just for interest's sake: is it possible to re-write the old noise/bumps
> function from scratch in povscript? Isn't the noise function iterative? 
> Is it possible to write iterative functions for the function pattern 
> or isosurface?

You could...but it would be a huge pain and would parse slowly. This was 
why I added noise3d() for use outside isosurfaces, and the eval_*() 
functions. And I wouldn't be able to, I don't know anything about noise 
and hash functions except for what they do.
BTW, what do you mean by "iterative function"? Do you mean recursive or 
looping?

-- 
Christopher James Huff - Personal e-mail: chr### [at] maccom
TAG(Technical Assistance Group) e-mail: chr### [at] tagpovrayorg
Personal Web page: http://homepage.mac.com/chrishuff/
TAG Web page: http://tag.povray.org/

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Chris Huff wrote:
> BTW, what do you mean by "iterative function"? Do you mean recursive or
> looping?

An iterative function is a function that uses a previous result
of itself at each step : 

Any fractal function is iterative.

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Hi again!

"Chris Huff" <chr### [at] maccom> wrote in message
news:chrishuff-DB8295.09271003072000@news.povray.org...
> I'm not sure what you mean...I meant something like this:
>
> #declare oldBozo = function {max(0, min(1, noise3d(x,y,z)*1.5 - 0.25))}

That's exactly what I meant... I guess I am too lazy - and maybe I like to
much being cryptic ;-)



<snip>
> BTW, what do you mean by "iterative function"? Do you mean recursive or
> looping?


Yes that's what I was trying to say. You are getting very good at reading
minds... now, let's do telekinesis :-)



Povingly,


Philippe

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