how to approximate a circle by s1356

[liufeijin]

we have 6 points want to approximate a circle by s1356 .
But seems get a b-spline curve not NURBS curve.
How can i to approximate NURBS curve?
I don't know how to set the weights for approximating a circle.

[tordokken]

Dear SISL user, When SISL was developed it was targeting curves and surfaces in Computer Aided Design and the approximation of a number of points to make a full circle represented as a NURBS curve was not a functionality requested. However, there is functionality to convert an ellipse to a NURBS, see: s1522 - Convert a 2D or 3D analytical ellipse to a curve. The curve will be geometrically exact. So you will have to first find the circle approximation yourself, and then s1522 can be used to make the rational expression. Tor From: liufeijin <[email protected]> Sent: fredag 26. oktober 2018 05.40 To: SINTEF-Geometry/SISL <[email protected]> Cc: Subscribed <[email protected]> Subject: [SINTEF-Geometry/SISL] how to approximate a circle by s1356 (#18) we have 6 points want to approximate a circle by s1356 . But seems get a b-spline curve not NURBS curve. How can i to approximate NURBS curve? I don't know how to set the weights for approximating a circle. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub<#18>, or mute the thread<https://github.com/notifications/unsubscribe-auth/AEJws1neTRz07roQm8RlO37L3hS009Pmks5uooQhgaJpZM4X7epp>.

[liufeijin]

Dear Tor
Many thanks for your explain.