In article <3d9c9e40$1@news.povray.org>,
 "Dennis Miller" <dhm### [at] attbicom> wrote:

> So will the spline respond to CL and move through the entire set of points?

If the T values for your points go from 0 to 1. The spline parameter 
*is* the T value, if it is equal to one of the T values in the spline, 
the return value will be the vector for that T value.


> In other words, does CL override the real clock settings? I'm just not clear
> on how the "ctr" parameter in the docs actually works.

No. It doesn't have anything to do with the clock settings. The macros 
set the variable CL to a number in a certain range depending on the 
clock value. The value of clock itself is unaffected, nothing is 
overridden.
Splines have nothing to do with clock, values that depend on clock are 
just often used for the spline parameter in animations. You seem to have 
some confusion from the fact that the spline parameter indicating the 
point on the spline is often called time.

It is really very simple:
Say you have a spline which has a T value of 0.2 at point A, and 0.7 at 
point B, and no points in between. If you give the spline 0.2 as the 
input parameter, you get point A, if you give 0.7, you get point B. If 
you give 0.5, you get something in-between, what exactly you get depends 
on the type of spline. The spline points are essentially "goal points", 
they tell the spline "be here when the parameter reaches this value".
The start of the spline is the point with the lowest T value, the end is 
the point with the highest. When the parameter is equal to the lowest 
value, it will return the start, when it is the highest it will return 
the end. If it is outside that range...well, that is probably a Bad 
Thing, I don't recommend it. Nothing ever relies on a [0, 1] range, that 
is simply a convention that is used when there isn't a good reason to 
use a different range.

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: chr### [at] tagpovrayorg
http://tag.povray.org/

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