Algorithm (Workflow)

This function, SGchecknonmanifoldvertices, is designed to identify non-manifold vertices in a given solid geometry (SG). Non-manifold vertices are points that are used in separate surfaces, which can cause issues in 3D modeling and printing.

Input Parameters

• SG: This is the Solid Geometry input, which represents the 3D model or object being analyzed.

Output Results

• vvi: An index list of non-manifold vertices, indicating vertices that are used multiple times across different surfaces.
• fi: An index list of faces attached to non-manifold vertices, showing which faces are connected to these problematic vertices.
• VL: The vertex list of the solid geometry, representing all the vertices in the model.
• FL: The facet list of the solid geometry, representing all the faces or surfaces in the model.

Algorithm Steps

1. The function begins by extracting the vertex list (VL) and facet list (FL) from the solid geometry (SG) using the helper function VLFLofSG(SG).
2. It checks the number of output arguments requested by the caller:
• If no output is requested (nargout==0), it calls VLFLchecknonmanifoldvertices(VL,FL) to perform the check and print the results using dbprintf.
• If outputs are requested, it calls VLFLchecknonmanifoldvertices(VL,FL) to obtain the indices of non-manifold vertices and the associated faces, storing them in vvi and fi respectively.

Example Usage

To use this function, you can load a 3D model, such as a robot, and check for non-manifold vertices:

loadweb JACO_robot.mat;
SG=JC3;  
SGchecknonmanifoldvertices(SG);

This example loads a model from a file and checks it for non-manifold vertices, which can help in identifying and fixing issues in the model.