BufferGeometry
I tweaked a little bit based on the understanding of Elias's fragmented sphere example. I wanted the extruded fragments triggered by mouse to be a enclosed shape. Therefore, I need to extent the vertex which shared with the intersected face as well.
Code hosted in the codeSandBox.
![](https://uploads-ssl.webflow.com/601eb2e704e9c7302fe3ad4e/60893ca6e303406eb3e37e56_%E6%88%AA%E5%B1%8F2021-04-28%20%E4%B8%8B%E5%8D%886.44.44.png)
So the result looks like this:
![](https://uploads-ssl.webflow.com/601eb2e704e9c7302fe3ad4e/60893cba61e2084a61e700c5_%E6%88%AA%E5%B1%8F2021-04-28%20%E4%B8%8B%E5%8D%886.39.40.png)
However, it didn't cover the indices that didn't share with them but still were part of the side faces.
Also, I wanted to detect the neighborhood faces around the intersected face but didn't know how. Any suggestions?
I finally got to know how the Voronoi diagram worked after looking into its theory. Here's the code and the demo. The art of code explained the code very clearly!
![](https://uploads-ssl.webflow.com/601eb2e704e9c7302fe3ad4e/60896ea0ae053af7e1d41c29_%E6%88%AA%E5%B1%8F2021-04-28%20%E4%B8%8B%E5%8D%8810.16.43.png)