Geoff Levner (geoff++at++mclink.it)
Tue, 15 Sep 1998 10:57:26 +0200
MultiGen allows you to choose from Bezier, B-splines or Cardinal
splines, so reproducing the same curve from the control points should
not be a problem. The problem is, MultiGen will not save them for you.
Apparently the only thing you can do is to make a polygon out of the
control points and save that. But if you want to modify the spline later
in MultiGen, you have to make a new spline by hand, using the points you
saved. Not very user-friendly.
I have not found anything better, however, so I think we will either
work that way or make our own spline editor.
> One final word about splines. If you are using splines for motion description,
> most splines, unlike linear interpolation, are not uniformly spaced, that is if
> you evaluate the spline at 4 different places but using the same delta u, you
> won't get the same delta distance ...
Yes, that is a problem. My original intention was to allow splines to be
"deparameterized", by subdividing them into nearly linear segments and
calculating the distance travelled, as you suggest. But if you do still
have those papers about redefining a spline for constant speed, I would
be interested in reading them....
Thanks,
Geoff
-- Geoff Levner -- geoff++at++mclink.it OR glevner++at++hotmail.com ACS Studio, Via Aurelia 58, 00165 Rome, Italy
This archive was generated by hypermail 2.0b2 on Tue Sep 15 1998 - 01:48:13 PDT