# Split edgeGeometry in fiber?

Hi,

How I can split an mesh having an “edgeGeometry” type of geometry in several mesh with fiber ?

Thank you

What is your criteria for splitting the geometry?
Without knowing that, I would say there is no way.
If you’re just trying to get nicely shaded objects from a crappy format without normals, Might I suggest the EdgeSplit modifier.

I would like to be able to split the edges of the white camembert into several edges and to move the m appart like the camembert is exploding.

Hmm still a bit vague. You want to split a geometry of 3000 vertices, into 3, 1000 vertex geometries?

What are you trying to implement on a high level? I can provide better answers with that info

I would like to be able to split the edges of the white camembert into several edges and to move the m appart like the camembert is exploding.

What you are describing sounds like pulling wedge slices out of a cylinder? Like slices of pizza or cake?

Splitting the geometry isn’t enough for that case, because there will be no interior faces.

However you can accomplish these kinds of things with a CSG tool… like three-bvh-csg:

or my library:

GitHub - manthrax/THREE-CSGMesh: Conversion of a CSG library for use with modern THREE.js (slower and older, but may have different material handling that is useful)

The approach here is you have your cylindrical object, and a triangular wedge/pie slice mesh… and you Subtract the wedge from the cylinder… that gives u your cake with the piece removed…( the interior faces then come from the wedge piece you used in the Subtract…)
then you do a union(?) or other operation on the wedge and the cake, to get the piece itself to move out…

ok I will have a look. The sandbox should be visible now. For my problem, I don’t understand than a edge geometry seems to have vertices and is not composed as a reunion of Line object. With line object there is no problem of internal, exterior surface.

Not sure it helps you a lot

Hmm I see… so you just want to extract that pie slice from the existing mesh.

split_cheese.glb (15.4 KB)
cheese.blend (955.4 KB)

I did it for you in blender.

You can do it purely in three, but its complicated… because how do you know which part is which? count the vertices? different materials? then you have to write the code to generate shared vertex list… color the graph, reduce the graph, and extract the groups… yuck

yeah I still don’t have enough knowledge to do this. I wanted to split only the edges of the cheese, not the whole

I highly recommend learning to use Blender. It will change your life.

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Obviously it is an off-topic, but got inspired by the idea of exploding cheese, so here you are a GLTF model of a tractor with `edgeGeometry` edges that explodes.

https://codepen.io/boytchev/full/VwNobLg

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