Wasn't it Rune who wrote:
>Mike Williams wrote:
>>Wasn't it Rune who wrote:
>
>>>I'm trying to make a long neck-like thing. I must be able
>>>to set the point where the neck starts and ends. Also the
>>>normal of the neck in these two points. ("normal" is
>>>probably not the right word. "Vector" or "direction" is
>>>probably better, but I'll just use "normal" here) I also
>>>want to control the length of the neck and the number of
>>>"links" or segments it is made of. ( The length of each
>>>"link" would then be [length-of-neck] / [number-of-links] )
>
>>Unfortunately, also, there's nothing that restrains the first and last
>>links to remain oriented along the specified vector, and the "pull" from
>>the other links causes them to be drawn noticeably off line. (I guess
>>that if you tweak the code to restrain the first and last link, then
>>you'd get a kink at link 2 and link n-1.)
>
>Yes, that's a problem.
>
>>I also guess that the curve to which this converges is actually the same
>>shape as a spline, but with equidistant points. You say that a spline
>>doesn't give you a very realistic neck bend, but I reckon that that's
>>the shape you'll end up with if you ever get this working.
>
>OK, I'll drop my original idea about adding forces to points in a spline.
>
>
>Instead I'll calculate the spline with the right total length and then try
>to use Peter Popov's method to figure equidistant points.
>
>However, I don't know yet how to calculate the spline with the right total
>length.
>
>>It's fairly easy to calculate the spline with the right total
>>length (performing a binary chop on the value I just tweaked above),
>
>Could you explain this in greater detail?

I'll post some code that does this to povray.binaries.scene-files.



-- 
Mike Williams #
Gentleman of Leisure

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