POV-Ray : Newsgroups : povray.advanced-users : SDL for a smooth spline? Server Time
3 Jul 2024 05:56:13 EDT (-0400)
  SDL for a smooth spline? (Message 1 to 5 of 5)  
From: gregjohn
Subject: SDL for a smooth spline?
Date: 28 Jan 2008 19:20:00
Message: <web.479e70a4e6e20bc934d207310@news.povray.org>
I'd like a way to generate a spline that is smooth, unlike linear_spline (uh,
and quadratic_spline), and defined across its entire range, unlike
cubic_spline.   Akima spline in the patched version does this well, but isn't
available to me in linux.

Can anyone show me how to make a smooth spline in SDL? thanks.


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From: Jim Charter
Subject: Re: SDL for a smooth spline?
Date: 28 Jan 2008 21:48:50
Message: <479e9412$1@news.povray.org>
gregjohn wrote:
> I'd like a way to generate a spline that is smooth, unlike linear_spline (uh,
> and quadratic_spline), and defined across its entire range, unlike
> cubic_spline.   Akima spline in the patched version does this well, but isn't
> available to me in linux.
> 
> Can anyone show me how to make a smooth spline in SDL? thanks.
> 
> 
> 
Isn't natural_spline that?  Else maybe something in Chris Colefax's 
spline kit would work?


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From: Meothuru
Subject: Re: SDL for a smooth spline?
Date: 29 Jan 2008 01:05:00
Message: <web.479ec15c745594d75a73e3b40@news.povray.org>
"gregjohn" <pte### [at] yahoocom> wrote:
> I'd like a way to generate a spline that is smooth, unlike linear_spline (uh,
> and quadratic_spline), and defined across its entire range, unlike
> cubic_spline.   Akima spline in the patched version does this well, but isn't
> available to me in linux.
>
> Can anyone show me how to make a smooth spline in SDL? thanks.


 www.f-lohmueller.de/pov_tut/animate/anim21e.htm


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From: gregjohn
Subject: Re: SDL for a smooth spline?
Date: 29 Jan 2008 07:30:00
Message: <web.479f1b43745594d734d207310@news.povray.org>
Jim Charter <jrc### [at] msncom> wrote:
> Isn't natural_spline that?  Else maybe something in Chris Colefax's
> spline kit would work?


Thanks, I had overlooked that one, didn't notice it in the docs.  It gets me
most of the way there, but it appears to give a straight line for the first and
last segment if one only defines a first and last point, no controls points.
Akima didn't do that.


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From: Alain
Subject: Re: SDL for a smooth spline?
Date: 29 Jan 2008 09:14:56
Message: <479f34e0@news.povray.org>
gregjohn nous apporta ses lumieres en ce 2008/01/29 07:25:
> Jim Charter <jrc### [at] msncom> wrote:
>> Isn't natural_spline that?  Else maybe something in Chris Colefax's
>> spline kit would work?
> 
> 
> Thanks, I had overlooked that one, didn't notice it in the docs.  It gets me
> most of the way there, but it appears to give a straight line for the first and
> last segment if one only defines a first and last point, no controls points.
> Akima didn't do that.
> 
> 
> 
> 
Any spline using only 2 points can only be straight. Any attempt to have such a 
spline curved would be uncontrolable.

-- 
Alain
-------------------------------------------------
Experience hath shewn, that even under the best forms of government those
entrusted with power have, in time, and by slow operations, perverted it
into tyranny.
Thomas Jefferson


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