I'm not sure if anyone actually uses these macros
of mine, but I've updated my Bezier-Splines macros,
which (from my point of view) provide a very intuitive
approach on spline-modelling.

The update introduces 2. Order continuancy, meaning
that tangential forces may vary for different sections of
a spline.

What does that mean?
Actually, one section is built with 4 vectors: 2 nodes defining
beginning and end point, and 2 directions defining tangents
for each point.
The Macros would take always a pair of 4 vectors and calculate
a section off of that. So, adding another 2 (1 node + 1 direction)
to the already existing four, the macro would create a section
curving from the end-point of the last section with its tangent to
the new one.
But the tangential force (its length) defines a very essential part
of the curving, and when using a strong force for one section,
it would have impact on the next.
So just yesterday I read a paragraph about the Bezier-Splines,
and stumbled upon this 2. Order continuancy. Basically, it states
that the splines' sections will still join smoothly if the tangent
stays the same, even though its force changes. That what I
implemented with the 4th component of the vectors.

Well, enough rambling. If anyones interested, its uploaded on
my homepage, if not, well... Don't know. Go play! :-)

Regards,
Tim
--
Tim Nikias
Homepage: http://www.digitaltwilight.de/no_lights/index.html
Email: Tim### [at] gmxde

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Hi. Could you post an example scene that used your spline macro to translate
the position of the camera?
thanks much,
Dennis
"Tim Nikias" <tim### [at] gmxde> wrote in message
news:3e515931@news.povray.org...
> I'm not sure if anyone actually uses these macros
> of mine, but I've updated my Bezier-Splines macros,
> which (from my point of view) provide a very intuitive
> approach on spline-modelling.
>
> The update introduces 2. Order continuancy, meaning
> that tangential forces may vary for different sections of
> a spline.
>
> What does that mean?
> Actually, one section is built with 4 vectors: 2 nodes defining
> beginning and end point, and 2 directions defining tangents
> for each point.
> The Macros would take always a pair of 4 vectors and calculate
> a section off of that. So, adding another 2 (1 node + 1 direction)
> to the already existing four, the macro would create a section
> curving from the end-point of the last section with its tangent to
> the new one.
> But the tangential force (its length) defines a very essential part
> of the curving, and when using a strong force for one section,
> it would have impact on the next.
> So just yesterday I read a paragraph about the Bezier-Splines,
> and stumbled upon this 2. Order continuancy. Basically, it states
> that the splines' sections will still join smoothly if the tangent
> stays the same, even though its force changes. That what I
> implemented with the 4th component of the vectors.
>
> Well, enough rambling. If anyones interested, its uploaded on
> my homepage, if not, well... Don't know. Go play! :-)
>
> Regards,
> Tim
> --
> Tim Nikias
> Homepage: http://www.digitaltwilight.de/no_lights/index.html
> Email: Tim### [at] gmxde
>
>

Post a reply to this message

Little scene uploaded, its in the ZIP-File.

Regards,
Tim

--
Tim Nikias
Homepage: http://www.digitaltwilight.de/no_lights/index.html
Email: Tim### [at] gmxde

> Hi. Could you post an example scene that used your spline macro to translate
> the position of the camera?
> thanks much,
> Dennis

Post a reply to this message

Ya, I did see that, but it doesn't apply the spline to camera movement so I
wonder which declaration I would use, for example, in a camera translate
statement, or is that the right approach?
best,
d.

"Tim Nikias" <tim### [at] gmxde> wrote in message
news:3e52214c@news.povray.org...
> Little scene uploaded, its in the ZIP-File.
>
> Regards,
> Tim
>
> --
> Tim Nikias
> Homepage: http://www.digitaltwilight.de/no_lights/index.html
> Email: Tim### [at] gmxde
>
> > Hi. Could you post an example scene that used your spline macro to
translate
> > the position of the camera?
> > thanks much,
> > Dennis
>
>

Post a reply to this message

No, I meant, I've added a new little scene in there, cam_spl.pov,
along with the old bspline_ex.pov.

What you actually do is access the spline using
BSpline_Pos( Spline, Mover)
with Spline being the identifier of the spline-array,
and Mover being a value ranging from 0 to 1 (beginning
to end of spline).
BSpline_Pos returns a simple <x,y,z>-vector, so you may
use it like this:

camera{
 location BSpline_Pos(My_Spline, clock)
 look_at <0,0,0>
}

(Just an example)

Regards,
Tim

--
Tim Nikias
Homepage: http://www.digitaltwilight.de/no_lights/index.html
Email: Tim### [at] gmxde
"Dennis Miller" <dhm### [at] attbicom> schrieb im Newsbeitrag
news:3e525c42$1@news.povray.org...
> Ya, I did see that, but it doesn't apply the spline to camera movement so I
> wonder which declaration I would use, for example, in a camera translate
> statement, or is that the right approach?
> best,
> d.
>
> "Tim Nikias" <tim### [at] gmxde> wrote in message
> news:3e52214c@news.povray.org...
> > Little scene uploaded, its in the ZIP-File.
> >
> > Regards,
> > Tim
> >
> > --
> > Tim Nikias
> > Homepage: http://www.digitaltwilight.de/no_lights/index.html
> > Email: Tim### [at] gmxde
> >
> > > Hi. Could you post an example scene that used your spline macro to
> translate
> > > the position of the camera?
> > > thanks much,
> > > Dennis
> >
> >
>
>

Post a reply to this message