I have been studying lathes/prisms/sors recently, and have come across an
inconsistency.

For Quadratic and Cubic splines, I have discovered that the only points that
are allowed to have -x values are the control points. That makes sense!

But for the bezier spline, while I cannot make the control points negative,
I CAN make the non-control points negative... why the inconsistency?
Shouldn't the points that are actually on the spline not be allowed -x
values, and the control points to be allowed -x values?

Ex. (Doesn't generate error)
lathe {
   bezier_spline
   4
   <-27.5,77.5>,
   <.5,30.5>, //Control Point!
   <.5,-65.5>, //Control Point!
   <-25.5,-79.5>
    sturm
   pigment {color rgb<1, 0, 0>}
 }

Ex. 2 (Does generate error)

lathe {
   bezier_spline
   4
   <27.5,77.5>,
   <-.5,30.5>, //Control Point!
   <-.5,-65.5>, //Control Point!
   <25.5,-79.5>
    sturm
   pigment {color rgb<1, 0, 0>}
 }


I dont belive I have my control points mixed up: (Povray Help)

    The bezier_spline is an alternate kind of cubic spline. Points 1 and 4
specify the end points of a segment and points 2 and 3 are control points
which specify the slope at the endpoints. Points 2 and 3 do not actually lie
on the spline.

By the way, this isnt an error report, but im using Beta 14 :-)

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