@sugolini said:
Thank you!
Now I've a strange problem with splines. I select, for example, uniform B-spline. Then I click one point in my drawing. It seems that I can move the pointer in each direction except directions with angle less than 15 degrees or so on with respect to x and y axis. I hope you got the point. It's quite unnerving, because if I want to connect a point A with a point B and such a segment forms an angle smaller than nearly 15° with the x-axis, then the pointer is attracted by a point on the x-axis!
In BezierSpline, I use the default snapping and inferencing of Sketchup.
So the best is to follow the method given by Mitcorb.
Fredo