Mesh boundaries form along boundary edges. ScanTo3D can create boundary curves only along boundary edges. Boundary edges are commonly found on meshes that represent surfaces or have large holes in them.
| To create a boundary edge, the mesh edge must have only one triangle touching the edge for a given location. For example, the triangles along the yellow edge are the only triangles touching the mesh edge, so the yellow edge is a boundary edge. |
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| In this example, the red edge (called an inner edge) has two triangles touching it. You cannot create a boundary curve along an inner edge. |
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