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"Chris B" <nom### [at] nomail com> wrote:
> These are fairly arbitrary values that you can think of in a number of
> different ways. It's like a 4th dimension that you can use to index how far
> through the spline you are, but you can really choose what you consider this
> index to represent.
To be honest I cannot say these values are arbitrary ones because they have
strong impact on the spline shape. Besides, following spline is wrong and
povray returns an error: "Parse Error: Degenerate cylinder, base point = apex
point." It means I cannot define these values in whatever manner I like.
#declare mySpline = spline {
quadratic_spline
1, <0,0,0>,
2, <1,1,0>,
3, <2,1,0>,
}
> The help suggests thinking of it as time, which is handy when you do
> animations. I usually set it so that the first physical point on the spline
> starts at 0 and the last point ends at 1. This means that in animations it's
> easy to use it with the clock variable to step along the spline in equally
> sized time slices.
I can think of these values as a "timestamps", but they shouldn't change the
spline shape!
> When defining a curve in a scene (rather than when using it for animation)
> you can just consider it as an amount that represents how far through the
> spline definition you are. So if you still start the spline at 0 and end at
> 1, then 0.5 can represent half way through the spline definition, though
> it's important to realise that this is not a distance, so it may be nowhere
> near the physical mid-point of the spline.
?
> Any help?
Still confused...
> Regards,
> Chris B.
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