Mesh Shell

Hollow a mesh by offsetting its surface inward along each vertex normal, then stitching the boundary edges so the result is closed. The output of Mesh Shell on a solid is two concentric shells (outer = original, inner = offset copy with reversed winding). Open meshes get a wall ring bridging outer and inner along every boundary edge.

Node

Interactive preview is available in the interactive reader.

Sockets

mesh (in): Mesh. Required.
thickness (in): Float. Optional thickness override.
mesh (out): Mesh — the hollow shell.

Parameters

Thickness: Offset distance along the inward normal. Positive values shell inward (hollow), negative values offset outward (puff up the surface). Default: 1.

How It Works

For every vertex, compute or reuse its smooth normal.
Emit both the original vertex and a copy translated by -normal * thickness.
For every triangle, emit the outer triangle and a reverse-wound inner triangle (so inner normals face the cavity).
Detect boundary edges (those referenced by exactly one triangle), and bridge outer → inner with a quad (two triangles) along each boundary edge.