6
$\begingroup$

I have been trying for some time with geometry nodes to detect the angle between two edges that are connected by a vertex.

My intention is to use that to spawn cubes or spheres at each vertex depending on whether or not the connecting two edges are convex or concave like the example in my image.

example vertex group

$\endgroup$
4
  • $\begingroup$ I've asked this specific question in several forums, and the only answer that seems to work at all involves extruding all the edges and then using a node to get the angles between the faces you've extruded. I hope someone here has a better one. $\endgroup$ Apr 4, 2022 at 20:12
  • $\begingroup$ @MartyFouts oh interesting, I haven't come across that info. If you can could you point me to some of them forum posts ? $\endgroup$
    – SarahLee
    Apr 4, 2022 at 21:51
  • $\begingroup$ Looks like someone has just posted an example. If that's not enough let me know and I'll dig things up. $\endgroup$ Apr 4, 2022 at 23:43
  • $\begingroup$ If your question was solved, please be so kind and mark the answer that contributed to the solution as "Accepted Answer". This will make it easier for others to see which way leads to the solution, and the question will no longer appear as unsolved. Thank you! Here you can find more information: What should I do when someone answers my question?. If you still didn't get a solution to your question, please be kind enough to address it. $\endgroup$
    – quellenform
    Aug 28, 2022 at 10:41

1 Answer 1

13
$\begingroup$

It depends a bit on how you generate the edges, with a clean mesh like that you could transfer the angle of some adjacent edge to each vertex and use 'Signed Angle' to pick an instance object... if you have only the edges it's more difficult, besides it's somehow arbitrary what's a 90 or a 270 angle

node setup

first blend file


Here's another option with pure edges, it checks against a vertical vector, normal to the edges plane. I tried converting edges to curves to be able to use L/R handles for each point, it also orders indexes as a bonus...

node setup

second blend file

and if you need the angles as the title suggests something like this could help...
maybe combine both setups to get signed angles

node setup

$\endgroup$

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .