VLFLchecknonmanifoldedges
by Tim C. Lueth, SG-Lib Toolbox: SolidGeometry 5.6 - Problems Find/Check/Fix
Introduced first in SolidGeometry 4.3, Creation date: 2018-08-24, Last change: 2025-09-14
returns the edges and facets with non manifold edges
Description
This function should return the same results as the output of Meshlab from http://vcg.isti.cnr.it
See Also: , VLFLchecknonmanifoldvertices
Example Illustration
Syntax
[NMEL,FLi]=VLFLchecknonmanifoldedges(VL,FL);
Input Parameter
VL: | | Vertex list |
FL: | | Facet list |
Output Parameter
NMEL: | | Edge list of non manifold eges |
FLi: | | facet index list of problematic facets |
Examples
SG=SGsample(14); VLFLchecknonmanifoldedges(SG.VL,SG.FL)
SG=SGsample(35); VLFLchecknonmanifoldedges(SG.VL,SG.FL)
Copyright 2018-2025 Tim C. Lueth. All rights reserved. The code is the property of Tim C. Lueth and may not be redistributed or modified without explicit written permission. This software may be used free of charge for academic research and teaching purposes only. Commercial use, redistribution, modification, or reverse engineering is strictly prohibited. Access to source code is restricted and granted only under specific agreements. For licensing inquiries or commercial use, please contact: Tim C. Lueth
Algorithm (Workflow)
This function, VLFLchecknonmanifoldedges, is designed to identify non-manifold edges in a 3D mesh. It takes two input parameters and provides two output results.
Input Parameters
- VL: Vertex List - A list of vertices that define the 3D mesh.
- FL: Facet List - A list of facets (triangles) that define the connections between vertices in the mesh.
Output Results
- NMEL: Non-Manifold Edge List - A list of edges that are identified as non-manifold.
- FLi: Facet Index List - A list of indices pointing to problematic facets that contain non-manifold edges.
Algorithm Steps
- Generate a list of edges from the facet list using the function
ELofFL(FL).
- Identify unique edges using
unique(EL,'rows','stable') and find non-manifold edges by determining the difference between all edges and unique edges.
- Store the non-manifold edges in
NMEL.
- If the number of output arguments is zero or more than one, identify facets that contain non-manifold edges using logical indexing with
ismember.
- If no output is specified, visualize the mesh and highlight non-manifold edges and problematic facets using plotting functions like
VLFLplot and VLELplots.
- Print the number of non-manifold edges and the number of faces over these edges.
Algorithm explaination created using ChatGPT on 2025-08-19 08:21. (Please note: No guarantee for the correctness of this explanation)
Last html export of this page out of FM database by TL: 2025-09-21