[QUESTION] How to keep this point after Group Combine?

[neblina]

Please see screenshots attached. After running a Voronoi Fracture, I use the original shape's points as the first group, and try to intersect with a second one.

The problem is, whenever one of the fractured pieces' points land on the same position as the original corner points, I can't separate them anymore. In this case, in the same position are points 7 and 15, but both of them get unselected when I group combine. Is this SOP solely based on Position attribute?

I'm trying to find a way to always extract only the 'internal' curves, any ideas? Thanks in advance.

[Noobini]

i'm not even sure if i fully understood your question...but just reading the last line...if you want to select the internal edges...then why not select all the borders (damn easy)...then 'invert'...voila....?

Sample here...tho playing around with it...there are some cases it doesn't work ...still investigating...

Ahh..found it...have to enable Fix Overlaps

 

internalEdges.hipnc

Edited November 19, 2017 by Noobini

[neblina]

First off thank you, and sorry for it being a bit confusing.

This solution works great in your file. My problem I think is that on my Voronoi Fracture I don't have 'Create Inside Surface' nor 'Connect Inside Edges' enabled (this somehow yielded the best results so far in terms of amount of edges I wanted and their configuration). Is there a way to make it work without those selected? If not, I'll have to figure out something else.

Great technique with the Edge grouping, thanks. Learned another one.

Edited November 19, 2017 by neblina

[Noobini]

I've just tested mine by disabling both Create Inside surface and Connect Inside Edges....still works fine...is it possible that you upload your scene for examination ?