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comparison scripts/plot/draw/private/__unite_shared_vertices__.m @ 22232:a8fd02bc895b

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Overhaul isosurface.m and associated functions. * isosurface.m: Rewrite docstring and examples. Don't validate nargout. Wrap long lines to < 80 characters. Use names from docstring in code. Use "EdgeColor", "none" for Matlab compatibility, but preserve exception for gnuplot. Use blank lines between case statements for readability. Update demo #2 to properly show annotation textbox. Rewrite %!error tests. * __calc_isovalue_from_data__.m: Give private function a docstring. Use '_' in numbers as thousands separator for readability. Wrap long lines to < 80 characters. * __unite_shared_vertices__.m: Reformat docstring. Use rows() rather than size (XXX, 1). Wrap long lines to < 80 characters. Use space after function name and before parenthesis.
author Rik <rik@octave.org>
date Tue, 09 Aug 2016 11:09:38 -0700
parents 7680225527ef
children 3a2b891d0b33 e9a0469dedd9
comparison
equal deleted inserted replaced
22231:01ba6ebc52e4 22232:a8fd02bc895b
17 ## <http://www.gnu.org/licenses/>. 17 ## <http://www.gnu.org/licenses/>.
18 18
19 ## -*- texinfo -*- 19 ## -*- texinfo -*-
20 ## @deftypefn {} {[@var{faces}, @var{vertices}, @var{J}] =} __unite_shared_vertices__ (@var{faces}, @var{vertices}) 20 ## @deftypefn {} {[@var{faces}, @var{vertices}, @var{J}] =} __unite_shared_vertices__ (@var{faces}, @var{vertices})
21 ## 21 ##
22 ## Detect and unite shared vertices in patches 22 ## Detect and unite shared vertices in patches.
23 ## 23 ##
24 ## Vertices of neighboring faces are detected and united to shared vertices. For 24 ## Vertices of neighboring faces are detected and united to shared vertices.
25 ## this, the mutual squared distances between all vertices are calculated. If 25 ## For this, the mutual squared distances between all vertices are
26 ## all coordinates are closer than @command{2 * eps (max (abs (vertices(:))))}, 26 ## calculated. If all coordinates are closer than
27 ## the vertices are united to one. 27 ## @code{2 * eps (max (abs (vertices(:))))}, the vertices are united to one.
28 ## 28 ##
29 ## @var{J} holds the indices of the deleted vertices. 29 ## @var{J} holds the indices of the deleted vertices.
30 ## 30 ##
31 ## @seealso{isosurface, reducepatch} 31 ## @seealso{isosurface, reducepatch}
32 ## @end deftypefn 32 ## @end deftypefn
33 33
34 ## Author: mmuetzel 34 ## Author: mmuetzel
35 35
36 function [faces, vertices, J] = __unite_shared_vertices__ (faces, vertices) 36 function [faces, vertices, J] = __unite_shared_vertices__ (faces, vertices)
37 ### unite shared vertices
38 37
39 J = []; 38 J = [];
39
40 ## Calculate the mutual differences of all vertex coordinates 40 ## Calculate the mutual differences of all vertex coordinates
41 close_points = zeros (0, 2); 41 close_points = zeros (0, 2);
42 num_vertices = size (vertices, 1); 42 num_vertices = rows (vertices);
43 skip_point = false (num_vertices, 1); 43 skip_point = false (num_vertices, 1);
44 ## FIXME: Can this be vectorized in some way to increase performance?
45 ## Regardless, should probably allocate close_points to be the
46 ## same size as the number of vertices and then truncate the
47 ## array at the end of the calculation. Extending an array
48 ## involves a copy operation every time.
44 for (i_point1 = 1:num_vertices - 1) 49 for (i_point1 = 1:num_vertices - 1)
45 if (skip_point(i_point1)) 50 if (skip_point(i_point1))
46 ## points already detected as duplicates can be skipped 51 ## points already detected as duplicates can be skipped
47 continue 52 continue;
48 endif 53 endif
49 54
50 diff = vertices(i_point1,:) - vertices(i_point1 + 1:end,:); 55 diff = vertices(i_point1,:) - vertices(i_point1 + 1:end,:);
51 is_close_point = all (abs (diff) <= sqrt(3) * eps * ... 56 is_close_point = all (abs (diff) <= sqrt (3) * eps * ...
52 (max (abs (vertices(i_point1,:)), abs (vertices(i_point1 + 1:end,:)))), 2); 57 (max (abs (vertices(i_point1,:)), abs (vertices(i_point1 + 1:end,:)))), 2);
53 58
54 if (any (is_close_point)) 59 if (any (is_close_point))
55 close_points_idx = find (is_close_point) + i_point1; 60 close_points_idx = find (is_close_point) + i_point1;
56 new_close_points_num = size (close_points_idx, 1); 61 new_close_points_num = rows (close_points_idx);
57 close_points(end + 1:end + new_close_points_num,1) = i_point1; 62 close_points(end + 1:end + new_close_points_num,1) = i_point1;
58 close_points(end - new_close_points_num + 1:end,2) = close_points_idx; 63 close_points(end - new_close_points_num + 1:end,2) = close_points_idx;
59 skip_point(close_points_idx) = true; 64 skip_point(close_points_idx) = true;
60 endif 65 endif
61 endfor 66 endfor
74 79
75 ## eliminate identical faces 80 ## eliminate identical faces
76 faces = sort (faces, 2); 81 faces = sort (faces, 2);
77 faces = unique (faces, "rows"); 82 faces = unique (faces, "rows");
78 83
79 ## eliminate faces with zero area 84 ## eliminate faces with zero area. Vertices in faces are sorted.
80 is_zero_area = (faces(:,1) == faces(:,2)) | (faces(:,2) == faces(:,3)); # vertices in faces are sorted 85 is_zero_area = (faces(:,1) == faces(:,2)) | (faces(:,2) == faces(:,3));
81 faces = faces(!is_zero_area,:); 86 faces = faces(! is_zero_area, :);
82 87
83 J = close_points(:,2); 88 J = close_points(:,2);
84 endif 89 endif
85 90
86 endfunction 91 endfunction
92