Constructing a Spherical Segment[br][br]The curve command: curve[ x(A) cos(t) + x(C) sin(t) , y(A) cos(t) + y(C) sin(t) , z(A) cos(t) + z(C) sin(t) , t, 0, angle[A,O,B]] [br][br]The screencast: [url]http://screencast-o-matic.com/watch/c2i0q2nJ5A[/url]