plottetra

 hm=plottetra(node,elem,opt)

 plot 3D surface meshes
 
 author: Qianqian Fang <fangq at nmr.mgh.harvard.edu>

 input: 
      node: a node coordinate list, 3 columns for x/y/z; if node has a 
            4th column, it will be used to set the color at each node.
      elem: a tetrahedral element list; if elem has a 5th column,
            and the 5th column are all integers, it will be treated
            as labels of sub-domains and display them in different colors.
            if the 5th column contains non-integer values, it will be
            used to map to the color of triangles.
      opt:  additional options for a patch object, see plotmesh

 output:
   hm: handle or handles (vector) to the plotted surfaces

 example:

   h=plottetra(node,elem);
   h=plottetra(node,elem,'facealpha',0.5);
 
 -- this function is part of iso2mesh toolbox (http://iso2mesh.sf.net)

0001 function hm=plottetra(node,elem,varargin)
0002 %
0003 % hm=plottetra(node,elem,opt)
0004 %
0005 % plot 3D surface meshes
0006 %
0007 % author: Qianqian Fang <fangq at nmr.mgh.harvard.edu>
0008 %
0009 % input:
0010 %      node: a node coordinate list, 3 columns for x/y/z; if node has a
0011 %            4th column, it will be used to set the color at each node.
0012 %      elem: a tetrahedral element list; if elem has a 5th column,
0013 %            and the 5th column are all integers, it will be treated
0014 %            as labels of sub-domains and display them in different colors.
0015 %            if the 5th column contains non-integer values, it will be
0016 %            used to map to the color of triangles.
0017 %      opt:  additional options for a patch object, see plotmesh
0018 %
0019 % output:
0020 %   hm: handle or handles (vector) to the plotted surfaces
0021 %
0022 % example:
0023 %
0024 %   h=plottetra(node,elem);
0025 %   h=plottetra(node,elem,'facealpha',0.5);
0026 %
0027 % -- this function is part of iso2mesh toolbox (http://iso2mesh.sf.net)
0028 %
0029 
0030 rngstate = rand ('state');
0031 
0032 randseed=hex2dec('623F9A9E'); % "U+623F U+9A9E"
0033 if(isoctavemesh) randseed=randseed+3; end
0034 
0035 if(~isempty(getvarfrom({'caller','base'},'ISO2MESH_RANDSEED')))
0036         randseed=getvarfrom({'caller','base'},'ISO2MESH_RANDSEED');
0037 end
0038 rand('state',randseed);
0039 
0040 if(~iscell(elem))
0041     if(size(elem,2)>4)
0042         tag=elem(:,5);
0043         types=unique(tag);
0044         hold on;
0045         h=[];
0046                 if(all(isinteger(tag)))
0047             for i=1:length(types)
0048             idx=find(tag==types(i));
0049             face=volface(elem(idx,1:4));
0050                     if(size(node,2)==3)
0051                 h=[h plotsurf(node,face,'facecolor',rand(3,1),varargin{:})];
0052             else
0053                             h=[h plotsurf(node,face,varargin{:})];
0054                         end
0055                     end
0056                 else
0057                     [face,eid]=volface(elem(:,1:4));
0058                     if(size(elem,2)>=5)
0059                         h=[h plotsurf(node,face,'FaceVertexCData',tag(eid), varargin{:})];
0060                     else
0061                         h=[h plotsurf(node,face,varargin{:})];
0062                     end
0063                 end
0064     else
0065         face=volface(elem(:,1:4));
0066         h=plotsurf(node,face,varargin{:});
0067     end
0068 end
0069 
0070 if(~isempty(h)) 
0071   axis equal;
0072 end
0073 if(~isempty(h) & nargout>=1)
0074   hm=h;
0075 end
0076 
0077 rand ('state',rngstate);