gmoffread.m

matlab有限元分析工具,比经较全面的一个手册,请大家下载呀

function b = gmoffread(filename, tol)
% gmoffread: read a brep from a file in OFF format
% b = gmoffread(filename)
% This routine reads a brep in OFF format from a file.
% See the documentation for a description of OFF format.
% OFF format was developed at the University of Minnesota
% Geometry Center.

if nargin < 2
  global GM_DEFAULT_TOL;
  tol = GM_DEFAULT_TOL;
end

fi = fopen(filename,'r');
if fi < 0
  error(sprintf('File %s not found', filename))
end
lineco = 1;

line = gm_strim(fgetl(fi));
lineco = lineco + 1;
if ~strcmpi(line, 'off')
  error('File must begin with keyword OFF')
end

a = sscanf(fgetl(fi), '%d %d %d');
lineco = lineco + 1;

if length(a) ~= 3
  error ('Second line of file must contain three integers')
end
numvtx = a(1);
numfacet = a(2);
numedge = a(3);
cplist = zeros(3,numvtx);
topvertices = cell(5,numvtx);
for vnum = 1 : numvtx
  coord = sscanf(fgetl(fi), '%e %e %e');
  if length(coord) ~= 3
    errmsg = sprintf('Each vertex line must contain three coordinates (error on line %d)', lineco);
    error(errmsg)
  end
  lineco = lineco + 1;
  cplist(:,vnum) = coord;
  vlist{1,vnum} = sprintf('v%d', vnum - 1);
  vlist{2,vnum} = {};
  vlist{3,vnum} = {};
  vlist{4,vnum} = {};
  vlist{5,vnum} = {'vertex'; []; [vnum - 1]};
end

elist = {};
slist = cell(5,numfacet);
basicscanstr = '%e ';
ecount = sparse([],[],[],numvtx,numvtx);
ehash = sparse([],[],[],numvtx,numvtx);
totalnume = 0;
rbdry = {};
for fnum = 1 : numfacet
  li = fgets(fi);
  numv = sscanf(li, '%d');
  if length(numv) == 0
    errmsg = sprintf('Missing vertex count field in facet entry (line #%d)', ...
                       lineco);
    error(errmsg);
  end
  numv = numv(1);
  idx = [1;2;3] * ones(1,numv + 4);
  scanstring = basicscanstr(idx(:));
  rval = sscanf(li, scanstring);
  if length(rval) ~= numv + 1 & length(rval) ~= numv + 4
    errmsg = sprintf('Facet has wrong number of entries (line #%d)', lineco);
    error(errmsg);
  end
  if length(rval) == numv + 1
    color = [];
  else
    color = rval(numv + 2 : numv + 4);
    if any(color < 0) | any(color > 1)
      error(sprintf('Color entry out of range (must be in [0,1]) (line #%d)', ...
          lineco));
    end
  end
  rval = rval(2:numv+1);

% deduplicate rval
  while any(rval(1:numv-1) == rval(2:numv))
    f1 = find(rval(1:numv-1) == rval(2:numv));
    f1 = f1(1);
    rval = [rval(1:f1);rval(f1+2:end)];
    numv = numv - 1;
  end
   

  if any(rval < 0 | rval >= numvtx)
    error(sprintf('Vertex index out of range (must be in 0..%d) (line #%d)', ...
          numvtx - 1, lineco));
  end
  lineco = lineco + 1;
  sbdry = cell(1,numv);
  thisvlist = zba(zeros(numv,3));
  thiselist = zeros(numv,2);
  for k = 1 : numv
    v1 = rval(k);
    if k == numv
      nextk = 1;
    else
      nextk = k + 1;
    end
    v2 = rval(nextk);
    thisvlist(k-1,:) = cplist(:,v1 + 1)';
    thiselist(k,:) = [k - 1,nextk - 1];
    if v2 < v1
      tmp = v2;
      v2 = v1;
      v1 = tmp;
    end
    ecount(v1+1,v2+1) = ecount(v1+1,v2+1) + 1;
    topidx = ehash(v1 + 1, v2 + 1);
    if topidx == 0
      totalnume = totalnume + 1;
      elist{1,totalnume} = sprintf('e%d', totalnume - 1);
      elist{2,totalnume} = {};
      elist{3,totalnume} = {sprintf('v%d',v1),sprintf('v%d',v2)};
      elist{4,totalnume} = {};
      elist{5,totalnume} = {'bezier_curve';[1];[v1,v2]};
      ehash(v1+1,v2+1) = totalnume;
      topidx = totalnume;
    end
    sbdry{k} = sprintf('e%d', topidx - 1);
  end
  trilist = gm_polytri(thisvlist, thiselist, tol);
  [numtri,scrap] = size(trilist);
  bezlist = cell(3,numtri);
  for l = 1 : numtri
    bezlist{1,l} = 'bezier_triangle';
    bezlist{2,l} = [1];
    bezlist{3,l} = rval(trilist(l,:)+[1,1,1]);
  end 
  slist{1,fnum} = sprintf('s%d', fnum - 1);
  rbdry{length(rbdry)+1} = sprintf('s%d', fnum - 1);
  if length(color) == 0
    slist{2,fnum} = {};
  else
    slist{2,fnum} = {'color'; sprintf('(%f %f %f 1)', ...
      color(1),color(2),color(3))};
  end
  slist{3,fnum} = sbdry;
  slist{4,fnum} = {};
  slist{5,fnum} = bezlist;
end
[el1,el2, v] = find(ecount);
emit2d = 0;
incorrecte = find(v~=2);
for jj = 1 : length(incorrecte)
  x = incorrecte(jj);
  disp(sprintf('Boundary does not close: edge %d,%d is contained by %d polygon(s) (should be 2)', el1(x), el2(x), v(x)))
  emit2d = 1;
end
global GM_BREP_TYPE_CODE
if emit2d == 1
  disp('Because boundary does not close, returned brep will have no regions');
  b = zba({GM_BREP_TYPE_CODE; 2; 3; {}; cplist; vlist; elist; slist});
else
  rlist = {'region'; {}; rbdry; {}; {}};
  b = zba({GM_BREP_TYPE_CODE; 3; 3; {}; cplist; vlist; elist; slist; rlist});
end


% ------------------------------------------------------------------
% Copyright (c) 1999 by Cornell University.  All rights reserved.
% See the accompanying file 'Copyright' for authorship information,
% the terms of the license governing this software, and disclaimers
% concerning this software.
% ------------------------------------------------------------------
% This file is part of the QMG software.  
% Version 2.0 of QMG, release date September 3, 1999
% ------------------------------------------------------------------