I'm writing a graphical spline editor for POV's splines and I'm having 
some difficulties to get my splines behave like POV's (POV 3.5 to be 
specific):

The main problem is the fact that splines from spline-identifiers like

#local myspline = spline {
	quadratic_spline
	0, <2,3>
	...
}

behave totally different from the ones used in lathe/prism It's not only 
that the syntax is different: If you've got a quadratic spline lathe 
with 3 points, it will only evaluate between points 2 and 3. Quadratic 
splines from spline identifiers will, in contrast, evaluate between all 
three points. Whereas if you're using a cubic spline with 4 points both 
types behave the same way (which is they evaluate only between points 2 
and 3).

So: What is the idea behind this? Will the concept of splines be changed 
to a more uniform one in POV 4.0 (yes, I did read the output on the 
message window telling me that splines are a experimental feature :)?

And I got another 2 questions (which are unrelated to the questions above):
- Why isn't it possible to use bezier_spline in spline identifiers?
- How are the clock values for the splines of lathe/prism computed? I 
guess they are chosen proportional (?) to the distance of the points, is 
this right?

Thanks for any hints
Florian

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