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chief
10-28-2002, 10:45 PM
Any one know a good code in order to compute the near point in a spline to a given point?
Thanks in advance

V-man
10-29-2002, 07:29 AM
mmm... perhaps finding the closest point on the polyline hull will work or give a reasonably close result in some cases.

Ask in a comp.algorithms group

V-man

martin_marinov
10-29-2002, 08:02 AM
Hi,

Please see my reply in this thread: http://www.opengl.org/discussion_boards/ubb/Forum3/HTML/002519.html
it gives the basic way to find an exact solution of the problem. It is usually faster than the approximation approach.

Regards
Martin

martin_marinov
10-29-2002, 08:09 AM
Hi,

Sorry, you actually asked for a solution in the general spline case. So for it you can use the fact that the spline is a polynomial between every two succesive control points/knots. Then you use the numerical method described in the thread which I mentioned above.
If the used basis are the BSplines, then finding this polynomial is usually trivial - depending of the spline order. In case you use dont use compact functions basis, it is a bit harder...

Regards
Martin



[This message has been edited by martin_marinov (edited 10-29-2002).]