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?

Greetings,

Rune

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