Barron Gillon wrote in message <3cacf454@news.povray.org>...
>Is there any built in way to find the exact length of a spline in POV 3.5?

Mark Wagner <mar### [at] gtenet> replied:
> POV-Ray doesn't know or care about the length of a spline.  In fact, I
don't
> know if it's even possible to calculate the exact length of a cubic or
> natural spline.

I don't believe it is - from my studies of splines a while back it seems the
integration of the relevant functions just isn't possible.  The easiest way
to find a spline's length, then, is probably sampling linear distances at
steps along the spline.  Also, a rough approximation can be calculated using
the bezier hull length.  My own Spline Macro File
(http://www.geocities.com/ccolefax) uses both methods to allow returning the
length of splines and other features like constant-speed traversing of
spline paths.

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