VLFLofCPL

by Tim C. Lueth, SG-Lib Toolbox: SolidGeometry 5.6 - Surfaces
Introduced first in SolidGeometry 4.0, Creation date: 2017-07-16, Last change: 2025-09-14

returns the vertex and facet list from a closed contour list

See Also: VLFLofCPLz , VLFLofCPLrot

Example Illustration

Syntax

[VL,FL]=VLFLofCPL(CPL)

Input Parameter

CPL: CPL

Output Parameter

`VL`:		Vertex list
`FL`:		Facet list

Examples


pc=PCofSG(SGsample(25),30000); 
SGfigure; VLplot(pc.Location,'r*',2);
axis(axis*1.1); axis off; CPL=CPLofimage(getframe(gca)); VLFLofCPL(CPL); view(0,90)

Copyright 2017-2025 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, VLFLofCPL, is designed to generate a vertex list (VL) and a facet list (FL) from a closed contour list (CPL). It is part of the SG-Library and was introduced in SolidGeometry 4.0.

Input Parameters

CPL: The closed contour list from which the vertex and facet lists are derived.

Output Results

VL: The vertex list, which contains the coordinates of the vertices.
FL: The facet list, which contains the connectivity information of the facets.
TR: The Delaunay triangulation object.

Algorithm Steps

Call the function PLELofCPL with CPL as input to obtain the point list PL and edge list EL.
Create a Delaunay triangulation object TR using PL and EL.
Extract the points from the triangulation object and assign them to VL.
Determine the interior triangles using isInterior(TR) and filter the connectivity list to obtain FL.
If no output arguments are specified, plot the vertex and facet lists using SGfigure, VLFLplot, and VLFLplotlight.

Example Usage

The example provided demonstrates how to use the function in conjunction with other functions from the SG-Library:

pc = PCofSG(SGsample(25), 30000);
SGfigure;
VLplot(pc.Location, 'r*', 2);
axis(axis * 1.1);
axis off;
CPL = CPLofimage(getframe(gca));
VLFLofCPL(CPL);
view(0, 90);

Algorithm explaination created using ChatGPT on 2025-08-18 23:14. (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