Extruding an Open Boundary and Applying Exterior Offset

[mofibo]

Hello MeshLib Team,

I am working with a mesh that has an open bottom surface. I already have the boundary vertices of this opening, along with their corresponding vertex indices.

My goal is to:

• Extrude this open boundary by a given height to form a planar (open) surface or wall.
• Merge the extruded geometry with the original mesh.
• Apply an exterior offset to the resulting mesh.

I attempted to construct a mesh object from the boundary vertices, and merge it with the original mesh, then applied stitch (fill holes) using MeshLib in order to close opened faces due to merge before applying the offset, however, this approach has not been reliable, in several cases, the stitching (hole filling) does not fully succeed, which leaves open faces after the merge, as a result, the offset operation sometimes fails or does not fully cover the mesh.

Is there a recommended or canonical MeshLib workflow (Python) for extruding an open boundary and preparing the mesh for a robust exterior offset?

Any guidance would be greatly appreciated.
Thank you for your time and support.

[Grantim]

Hello!

We have extendHole which does exactly what you describe: extruding open boundary to provided plane.

There is no need to do additional merging because it is already part of initial mesh. After extending you can just fillHole with planar metric.

So, you will get the hole extruded and filled, than you can perform offset.