Angle of point on bspline


How might I work out the rotation that should be applied (in 2d) to an object on a bspline so that it faces perpendicular to the direction of that point of the spline, like a normal would on a surface.

Have tried tangent without much luck. Lookat works but seems overkill.


Ok, I’ve just had a look inside Deform By Spline and see that the out’ and out" used with moving triad can kind of achieve this. Problem is, The rotation of the object around the bspline varies depending on the ‘bend’ of the curve but I want it not to, so that the object will always be on one ‘side’ of the curve.

Any ideas?

I meant Deform By Curve above…

I suppose I want to know how to convert DBC so that the input points do not rotate around the curve when the curve shape changes. Git meh?

I am not sure about your trouble, but you can try to stop the glitching/jumping by applying a filter.

Read here: (Tricks With Cyclic Filters)

Good luck!!

Cheers West.

Have solved the problem. Will try to post a patch

Hi I am also looking how to get the direction/rotation of elements along a b-spline. How did you solve it?

@mrboni : you have derivative output on b-spline, that’s what you need for this.

OK easily accomplished with moving triad…