How do you split 3D curves?

bruce_williams

@MBartlett21 did a great job with 3D Point to add points to 3D curves.  And composite is great for adding curves together.  How to split a 3D curve though?  Hoping someone has created a FS for that.

NeilCooke

Couldn't resist - here you go:
https://cad.onshape.com/documents/2731f42f4ae1c116a9d4a327/w/9376cec638160648b96a57c6/e/7d0f0f820add2c73886e2f92

The entities used for split do not have to intersect the curve, it just finds the nearest point. Let me know if you find any bugs.

bruce_williams

Really great to see this @NeilCooke   Thanks!

I did some testing and it seems to fail on other types of 'created' 3D curves - examples of Bridge, Project are in the copy document here.  There is an error on a surface boundary but that may be the underlying curve.

It does not seem to accept a Composite curve but I do not think that is a must since we can split the individual curves and then make new composite.

This is going to be a handy feature.

NeilCooke

I only did minimal testing so glad to fix it up for you. 

bruce_williams

@NeilCooke
looking forward to it.  I am in middle of tool design for automotive project and splitting curves is very helpful when working with imported geometry.  And I hope others besides me will benefit. 

btw the 'Highlight Boundary Edges' is working great.  Makes all the difference while repairing models.

NeilCooke

@bruce_williams - please give it another go. Existing features will fail because I've made so many changes, but you can edit and reselect the "curve to split" and it should fix itself. You can now add more than one curve/edge to the "edges or curves to split" and also split and split with curves (including composite curves).

For composite curves, only the underlying edge is split - so for example, if a CC is made up of 3 edges and the middle edge is split, the result would be two curves over the split edge, not two composite curves spanning the entire original CC, if that makes sense. I can't think of any way around this.

bruce_williams

Excellent!  Everything I try works including boundary edges, created curves, split by plane or surface face.  Sweet!  Thanks for getting this done so well & quickly.  Nice it takes more than one edge also.

Only thing I see - it seems to need the splitting entity to be on or intersect.  I tried points within .5mm and not working for that.  

NeilCooke

True - there was an issue with curves being split in strange places, so I had to change it to exact intersection - is that a big problem?

bruce_williams

@NeilCooke
No problem; just noticed the behavior was different.  Works fine - Considering you can use planes, faces, and 3Dpoint FS to get exact locations.