1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
|
## Copyright (C) 2024 David Legland
## All rights reserved.
##
## Redistribution and use in source and binary forms, with or without
## modification, are permitted provided that the following conditions are met:
##
## 1 Redistributions of source code must retain the above copyright notice,
## this list of conditions and the following disclaimer.
## 2 Redistributions in binary form must reproduce the above copyright
## notice, this list of conditions and the following disclaimer in the
## documentation and/or other materials provided with the distribution.
##
## THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ''AS IS''
## AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
## IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
## ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
## ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
## DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
## SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
## CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
## OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
## OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
##
## The views and conclusions contained in the software and documentation are
## those of the authors and should not be interpreted as representing official
## policies, either expressed or implied, of the copyright holders.
function checkMeshAdjacentFaces(vertices, edges, faces)
%CHECKMESHADJACENTFACES Check if adjacent faces of a mesh have similar orientation.
%
% checkMeshAdjacentFaces(VERTICES, EDGES, FACES)
% The functions returns no output, but if two faces share a common edge
% with the same direction (meaning that adjacent faces have normals in
% opposite direction), a warning is displayed.
%
% Example
% [v e f] = createCube();
% checkMeshAdjacentFaces(v, e, f);
% % no output -> all faces have normal outwards of the cube
%
% v = [0 0 0; 10 0 0; 0 10 0; 10 10 0];
% e = [1 2;1 3;2 3;2 4;3 4];
% f = [1 2 3; 2 3 4];
% checkMeshAdjacentFaces(v, e, f);
% Warning: Faces 1 and 2 run through the edge 3 (2-3) in the same direction
%
% See also
% meshes3d, trimeshMeanBreadth
%
% ------
% Author: David Legland
% E-mail: david.legland@inrae.fr
% Created: 2010-10-06, using Matlab 7.9.0.529 (R2009b)
% Copyright 2010-2023 INRA - Cepia Software Platform
% the message pattern that is displayed when an inconsistency is encountered
pattern = 'Faces %d and %d run through the edge %d (%d-%d) in the same direction';
% If edges are not specified, compute them
if nargin == 2
faces = edges;
edges = meshEdges(vertices, faces);
end
% compute edges to faces map
edgeFaces = meshEdgeFaces(vertices, edges, faces);
Ne = size(edgeFaces, 1);
for i = 1:Ne
% indices of extreimty vertices
v1 = edges(i, 1);
v2 = edges(i, 2);
% index of adjacent faces
indF1 = edgeFaces(i, 1);
indF2 = edgeFaces(i, 2);
% if one of the faces has index 0, then the edge is at the boundary
if indF1 == 0 || indF2 == 0
continue;
end
% vertices of adjacent faces
face1 = meshFace(faces, indF1);
face2 = meshFace(faces, indF2);
% position of vertices in face vertex array
ind11 = find(face1 == v1);
ind12 = find(face1 == v2);
ind21 = find(face2 == v1);
ind22 = find(face2 == v2);
% check if edge is traveled forward or backard
direct1 = (ind12 == ind11+1) | (ind12 == 1 & ind11 == length(face1));
direct2 = (ind22 == ind21+1) | (ind22 == 1 & ind21 == length(face2));
% adjacent faces should travel the edge in opposite direction
if direct1 == direct2
warning(pattern, indF1, indF2, i, v1, v2); %#ok<WNTAG>
end
end
|
