-
Notifications
You must be signed in to change notification settings - Fork 0
/
mesh_to_stl.m
312 lines (278 loc) · 13.7 KB
/
mesh_to_stl.m
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
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
function mesh_to_stl(N,E,r, num)
[dummy noEdg] = size(E);
Nx = [];
Fx = [];
for e = 1 : noEdg
%r = r + 0.1;
n1 = E(1,e);
n2 = E(2,e);
v1 = N(n1,:);
v2 = N(n2,:);
vImesh = v2-v1;
L = norm(vImesh);
[NN,FF] = edge_to_tube(L,r);
vTempl = [0 0 L];
if vImesh(1) == 0 && vImesh(2) == 0
vImesh = vImesh + 0.01;%[0 0 0.0001];
end
vCross = cross(vTempl,vImesh);
ang = atan2(norm(cross(vTempl,vImesh)), dot(vTempl,vImesh));
k = vCross/norm(vCross);
K = [0 -k(3) k(2) ; k(3) 0 -k(1 ); -k(2) k(1) 0];
R = eye(3) + (sin(ang))*K + (1-cos(ang))*K*K;
NN = (R*NN')';
NN = NN + v1;
Nx = [Nx;NN];
Fx = [Fx;FF+length(NN)*(e-1)];
end
figure(num)
clf;
axis equal;axis off;grid off;
set(gcf,'color',[0.0 0.0 0.0]);
set(gca,'Projection','perspective','view',[30 30]);
patch('Faces',Fx,'Vertices',Nx,'FaceColor',[1 0.5 0.5],'EdgeColor','none');
camlight('right');
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
STLstuct.vertices = Nx;
STLstuct.faces = Fx;
stlwrite(sprintf('struct_%i.stl', num),STLstuct);
function stlwrite(filename, varargin)
%STLWRITE Write STL file from patch or surface data.
%
% STLWRITE(FILE, FV) writes a stereolithography (STL) file to FILE for a
% triangulated patch defined by FV (a structure with fields 'vertices'
% and 'faces').
%
% STLWRITE(FILE, FACES, VERTICES) takes faces and vertices separately,
% rather than in an FV struct
%
% STLWRITE(FILE, X, Y, Z) creates an STL file from surface data in X, Y,
% and Z. STLWRITE triangulates this gridded data into a triangulated
% surface using triangulation options specified below. X, Y and Z can be
% two-dimensional arrays with the same size. If X and Y are vectors with
% length equal to SIZE(Z,2) and SIZE(Z,1), respectively, they are passed
% through MESHGRID to create gridded data. If X or Y are scalar values,
% they are used to specify the X and Y spacing between grid points.
%
% STLWRITE(...,'PropertyName',VALUE,'PropertyName',VALUE,...) writes an
% STL file using the following property values:
%
% MODE - File is written using 'binary' (default) or 'ascii'.
%
% TITLE - Header text (max 80 chars) written to the STL file.
%
% TRIANGULATION - When used with gridded data, TRIANGULATION is either:
% 'delaunay' - (default) Delaunay triangulation of X, Y
% 'f' - Forward slash division of grid quads
% 'b' - Back slash division of quadrilaterals
% 'x' - Cross division of quadrilaterals
% Note that 'f', 'b', or 't' triangulations now use an
% inbuilt version of FEX entry 28327, "mesh2tri".
%
% FACECOLOR - Single colour (1-by-3) or one-colour-per-face (N-by-3)
% vector of RGB colours, for face/vertex input. RGB range
% is 5 bits (0:31), stored in VisCAM/SolidView format
% (http://en.wikipedia.org/wiki/STL_(file_format)#Color_in_binary_STL)
%
% Example 1:
% % Write binary STL from face/vertex data
% tmpvol = false(20,20,20); % Empty voxel volume
% tmpvol(8:12,8:12,5:15) = 1; % Turn some voxels on
% fv = isosurface(~tmpvol, 0.5); % Make patch w. faces "out"
% stlwrite('test.stl',fv) % Save to binary .stl
%
% Example 2:
% % Write ascii STL from gridded data
% [X,Y] = deal(1:40); % Create grid reference
% Z = peaks(40); % Create grid height
% stlwrite('test.stl',X,Y,Z,'mode','ascii')
%
% Example 3:
% % Write binary STL with coloured faces
% cVals = fv.vertices(fv.faces(:,1),3); % Colour by Z height.
% cLims = [min(cVals) max(cVals)]; % Transform height values
% nCols = 255; cMap = jet(nCols); % onto an 8-bit colour map
% fColsDbl = interp1(linspace(cLims(1),cLims(2),nCols),cMap,cVals);
% fCols8bit = fColsDbl*255; % Pass cols in 8bit (0-255) RGB triplets
% stlwrite('testCol.stl',fv,'FaceColor',fCols8bit)
% Original idea adapted from surf2stl by Bill McDonald. Huge speed
% improvements implemented by Oliver Woodford. Non-Delaunay triangulation
% of quadrilateral surface courtesy of Kevin Moerman. FaceColor
% implementation by Grant Lohsen.
%
% Author: Sven Holcombe, 11-24-11
% Check valid filename path
path = fileparts(filename);
if ~isempty(path) && ~exist(path,'dir')
error('Directory "%s" does not exist.',path);
end
% Get faces, vertices, and user-defined options for writing
[faces, vertices, options] = parseInputs(varargin{:});
asciiMode = strcmp( options.mode ,'ascii');
% Create the facets
facets = single(vertices');
facets = reshape(facets(:,faces'), 3, 3, []);
% Compute their normals
V1 = squeeze(facets(:,2,:) - facets(:,1,:));
V2 = squeeze(facets(:,3,:) - facets(:,1,:));
normals = V1([2 3 1],:) .* V2([3 1 2],:) - V2([2 3 1],:) .* V1([3 1 2],:);
clear V1 V2
normals = bsxfun(@times, normals, 1 ./ sqrt(sum(normals .* normals, 1)));
facets = cat(2, reshape(normals, 3, 1, []), facets);
clear normals
% Open the file for writing
permissions = {'w','wb+'};
fid = fopen(filename, permissions{asciiMode+1});
if (fid == -1)
error('stlwrite:cannotWriteFile', 'Unable to write to %s', filename);
end
% Write the file contents
if asciiMode
% Write HEADER
fprintf(fid,'solid %s\r\n',options.title);
% Write DATA
fprintf(fid,[...
'facet normal %.7E %.7E %.7E\r\n' ...
'outer loop\r\n' ...
'vertex %.7E %.7E %.7E\r\n' ...
'vertex %.7E %.7E %.7E\r\n' ...
'vertex %.7E %.7E %.7E\r\n' ...
'endloop\r\n' ...
'endfacet\r\n'], facets);
% Write FOOTER
fprintf(fid,'endsolid %s\r\n',options.title);
else % BINARY
% Write HEADER
fprintf(fid, '%-80s', options.title); % Title
fwrite(fid, size(facets, 3), 'uint32'); % Number of facets
% Write DATA
% Add one uint16(0) to the end of each facet using a typecasting trick
facets = reshape(typecast(facets(:), 'uint16'), 12*2, []);
% Set the last bit to 0 (default) or supplied RGB
facets(end+1,:) = options.facecolor;
fwrite(fid, facets, 'uint16');
end
% Close the file
fclose(fid);
end
%% Input handling subfunctions
function [faces, vertices, options] = parseInputs(varargin)
% Determine input type
if isstruct(varargin{1}) % stlwrite('file', FVstruct, ...)
if ~all(isfield(varargin{1},{'vertices','faces'}))
error( 'Variable p must be a faces/vertices structure' );
end
faces = varargin{1}.faces;
vertices = varargin{1}.vertices;
options = parseOptions(varargin{2:end});
elseif isnumeric(varargin{1})
firstNumInput = cellfun(@isnumeric,varargin);
firstNumInput(find(~firstNumInput,1):end) = 0; % Only consider numerical input PRIOR to the first non-numeric
numericInputCnt = nnz(firstNumInput);
options = parseOptions(varargin{numericInputCnt+1:end});
switch numericInputCnt
case 3 % stlwrite('file', X, Y, Z, ...)
% Extract the matrix Z
Z = varargin{3};
% Convert scalar XY to vectors
ZsizeXY = fliplr(size(Z));
for i = 1:2
if isscalar(varargin{i})
varargin{i} = (0:ZsizeXY(i)-1) * varargin{i};
end
end
% Extract X and Y
if isequal(size(Z), size(varargin{1}), size(varargin{2}))
% X,Y,Z were all provided as matrices
[X,Y] = varargin{1:2};
elseif numel(varargin{1})==ZsizeXY(1) && numel(varargin{2})==ZsizeXY(2)
% Convert vector XY to meshgrid
[X,Y] = meshgrid(varargin{1}, varargin{2});
else
error('stlwrite:badinput', 'Unable to resolve X and Y variables');
end
% Convert to faces/vertices
if strcmp(options.triangulation,'delaunay')
faces = delaunay(X,Y);
vertices = [X(:) Y(:) Z(:)];
else
if ~exist('mesh2tri','file')
error('stlwrite:missing', '"mesh2tri" is required to convert X,Y,Z matrices to STL. It can be downloaded from:\n%s\n',...
'http://www.mathworks.com/matlabcentral/fileexchange/28327')
end
[faces, vertices] = mesh2tri(X, Y, Z, options.triangulation);
end
case 2 % stlwrite('file', FACES, VERTICES, ...)
faces = varargin{1};
vertices = varargin{2};
otherwise
error('stlwrite:badinput', 'Unable to resolve input types.');
end
end
if size(faces,2)~=3
errorMsg = {
sprintf('The FACES input array should hold triangular faces (N x 3), but was detected as N x %d.',size(faces,2))
'The STL format is for triangulated surfaces (i.e., surfaces made from 3-sided triangles).'
'The Geom3d package (https://www.mathworks.com/matlabcentral/fileexchange/24484-geom3d) contains'
'a "triangulateFaces" function which can be used convert your faces into triangles.'
};
error('stlwrite:nonTriangles', '%s\n',errorMsg{:})
end
if ~isempty(options.facecolor) % Handle colour preparation
facecolor = uint16(options.facecolor);
%Set the Valid Color bit (bit 15)
c0 = bitshift(ones(size(faces,1),1,'uint16'),15);
%Red color (10:15), Blue color (5:9), Green color (0:4)
c0 = bitor(bitshift(bitand(2^6-1, facecolor(:,1)),10),c0);
c0 = bitor(bitshift(bitand(2^11-1, facecolor(:,2)),5),c0);
c0 = bitor(bitand(2^6-1, facecolor(:,3)),c0);
options.facecolor = c0;
else
options.facecolor = 0;
end
end
function options = parseOptions(varargin)
IP = inputParser;
IP.addParamValue('mode', 'binary', @ischar)
IP.addParamValue('title', sprintf('Created by stlwrite.m %s',datestr(now)), @ischar);
IP.addParamValue('triangulation', 'delaunay', @ischar);
IP.addParamValue('facecolor',[], @isnumeric)
IP.addParamValue('facecolour',[], @isnumeric)
IP.parse(varargin{:});
options = IP.Results;
if ~isempty(options.facecolour)
options.facecolor = options.facecolour;
end
end
function [F,V]=mesh2tri(X,Y,Z,tri_type)
% function [F,V]=mesh2tri(X,Y,Z,tri_type)
%
% Available from http://www.mathworks.com/matlabcentral/fileexchange/28327
% Included here for convenience. Many thanks to Kevin Mattheus Moerman
% kevinmoerman@hotmail.com
% 15/07/2010
%------------------------------------------------------------------------
[J,I]=meshgrid(1:1:size(X,2)-1,1:1:size(X,1)-1);
switch tri_type
case 'f'%Forward slash
TRI_I=[I(:),I(:)+1,I(:)+1; I(:),I(:),I(:)+1];
TRI_J=[J(:),J(:)+1,J(:); J(:),J(:)+1,J(:)+1];
F = sub2ind(size(X),TRI_I,TRI_J);
case 'b'%Back slash
TRI_I=[I(:),I(:)+1,I(:); I(:)+1,I(:)+1,I(:)];
TRI_J=[J(:)+1,J(:),J(:); J(:)+1,J(:),J(:)+1];
F = sub2ind(size(X),TRI_I,TRI_J);
case 'x'%Cross
TRI_I=[I(:)+1,I(:); I(:)+1,I(:)+1; I(:),I(:)+1; I(:),I(:)];
TRI_J=[J(:),J(:); J(:)+1,J(:); J(:)+1,J(:)+1; J(:),J(:)+1];
IND=((numel(X)+1):numel(X)+prod(size(X)-1))';
F = sub2ind(size(X),TRI_I,TRI_J);
F(:,3)=repmat(IND,[4,1]);
Fe_I=[I(:),I(:)+1,I(:)+1,I(:)]; Fe_J=[J(:),J(:),J(:)+1,J(:)+1];
Fe = sub2ind(size(X),Fe_I,Fe_J);
Xe=mean(X(Fe),2); Ye=mean(Y(Fe),2); Ze=mean(Z(Fe),2);
X=[X(:);Xe(:)]; Y=[Y(:);Ye(:)]; Z=[Z(:);Ze(:)];
end
V=[X(:),Y(:),Z(:)];
end
end