NGON extract polylines problem

I have checked my mesh with meshrepair and it says the mesh is OK. However when I am trying to extract polylines from the mesh with NGON plugin only the upper part of the mesh is considered. Why? (7.9 KB)

The Get Polylines component you are using from the NGon plug-in only extracts the edges of ngons. This is why you’re only getting the 5 faces at the top of your mesh.

If you scroll down farther in the Mesh Repair window that you have open in your screenshot you will see this (I’ve just expanded the window instead of scrolling).

The opening at the top of your mesh looks like it has 5 edges but you can see that it has reported 9 naked edges. Look at the screenshot you posted and you can see the end points of these 9 edges.

In the upper part of the window it says the mesh doesn’t have any ngons, this seems incorrect since this mesh has 4 faces with 5 edges and 1 face with 4 edges.

The lower part of the window is identifying the 5 faces that have more than 3 edges as ngons.

If you bake your mesh and run the _DeleteMeshNgons or _RebuildMesh command you will get this.

You can see that it has divided those 5 ngons into triangles resulting in 14 faces.


Thanks for the explanation. However I am a bit confused. For me it seems to be a contradiction. If get polylines extract Ngons and according to mesh repair there are no ngons in the mesh, then Get Polylines should not extract any polylines at all. Isnt it?

Look at the bottom of the mesh repair window or the output of the _What command and you will see that it reports 5 ngons

As I explained above the mesh repair window reports 2 different results in the same screen - definitely a contradiction.

Your mesh has faces with 4 or 5 edges, it definitely has ngons.