How to reposition control points along the curve?

adding a new control point to a bezier curve by Subdivide method results in having it in a fixed position. How can I reposition the control point (along the curve) not affecting the shape?

If you want to move a control point along the curve but keep the curve’s shape, that implies that all the curve’s control points would have to be scaled dynamically to maintain the shape…

Scalled dynamically you say, but what I need is to solve the problem in a few easy steps. :spin:

Sorry for not being precise.
The aim is to move the point that in its original position is indifferent for the shape! (it maybe a duplication of any existing point for example). Moving it I still wish to preserve its neutrality for the shape, I just want to change ratio between those keypoints. Let’s pretend this new point could be achieved by knife tool.

Reaction is correct. By definition, if you simply reposition a control point, the curve must change shape. You would have to adjust the handles on the moved point and other points to make the curve look as it did before, and it might well be impossible. Since curves are so efficient, why not just subdivide between exisiting points on the curve, then delete the points you don’t want? What are you trying to do?

I need to cut out a part of a given bezier circle that forms the precisely x degree turn.
By the way how long should I recursively divide the circle to get to the point where x is exactly 77 ? :wink:
Or maybe Blender has a specialized tool for bending …

PS. CD38, what is the definition? Because I can give you infinitely many control points to any curve and than move them not affecting the shape at all. But I need just one to prove your definition is out of tune, let’s imagine a curve that is a straight line… :slight_smile:

You can try Spin a vertex by 77 degrees


Make circle , select point , set pivot point to 3dCursor , duplicate point , turn what angle you want.
This works well only for circles.

Syziph: it is not a story about meshes, it’s about curve objects.
Jawra: It would be great but duplicated control points for some reason have no affect on the curve (or am I doing something wrong?)

Apologize for that.
In a hurry I didn’t see the point is not connected.
I think Syziph made good start and only you need is to use script Mesh>Scripts>EdgesToCurve to make curve object from mesh edges.
Now I’ve tested and it’s working.

There is a video floating around that shows how to do this using dupliverts. From what I remember, you use duplivert on the original curve to equally distribute objects along the curve, then you draw a new curve at those object points.

It has been a while, and I don’t have a link, sorry.

vertex on a curve are like for mesh you select and change the postion
that’s all

but if you subdivide between two verticies it will cut the edge in 2 so the new vertex is on the edge and not as per the shape of the curve which is also true for meshes!

Now you can change the resolution of your curve to add or delete verticie between control points !

i don’t know if that’s what your need can you show pic with details ?


The goal is to allow any spot on the curve to become the new control point.
Just like you can cut an edge in any place to make a new vertex.
Besides this meshes should have nothing to do with it algorithmically, imho.
(but thanks for the tip)