plot_map_on_face

 plot channel data value on face
    h = plot_map_on_face(parm,facefile,ch_val,plot_parm)
 parm : pair channel structure
        source: {1xNsrc cell}
      detector: {1xNdet cell}
    probe_pair: [Npairx2 double]
       src_pos: [Nsrcx3 double]
       det_pos: [Ndetx3 double]
 facefile 
 ch_val : channel data value [Npairx1 double]
 plot_parm : 
    plot_parm.Msend = 'r.';
    plot_parm.Mrecv = 'b.';
    plot_parm.Msize = 20;
    plot_parm.mode
     = 0 : Smooth interpolation using 3 neighbor [default]
     = 1 : Binary mode (No pactch reduction & nearest neighbor interpolation)

 2015-7-1 Masa-aki Sato

 Copyright (C) 2011, ATR All Rights Reserved.
 License : New BSD License(see VBMEG_LICENSE.txt)

0001 function    h = plot_map_on_face(parm,facefile,ch_val,p)
0002 % plot channel data value on face
0003 %    h = plot_map_on_face(parm,facefile,ch_val,plot_parm)
0004 % parm : pair channel structure
0005 %        source: {1xNsrc cell}
0006 %      detector: {1xNdet cell}
0007 %    probe_pair: [Npairx2 double]
0008 %       src_pos: [Nsrcx3 double]
0009 %       det_pos: [Ndetx3 double]
0010 % facefile
0011 % ch_val : channel data value [Npairx1 double]
0012 % plot_parm :
0013 %    plot_parm.Msend = 'r.';
0014 %    plot_parm.Mrecv = 'b.';
0015 %    plot_parm.Msize = 20;
0016 %    plot_parm.mode
0017 %     = 0 : Smooth interpolation using 3 neighbor [default]
0018 %     = 1 : Binary mode (No pactch reduction & nearest neighbor interpolation)
0019 %
0020 % 2015-7-1 Masa-aki Sato
0021 %
0022 % Copyright (C) 2011, ATR All Rights Reserved.
0023 % License : New BSD License(see VBMEG_LICENSE.txt)
0024 
0025 % Reduced number of patch in face surface
0026 Npatch=10000; 
0027 
0028 if ~isfield(p,'mode'), p.mode=0; end
0029 
0030 % Face surface
0031 face = load(facefile);
0032 V = face.Vspm;
0033 F = face.F;
0034 
0035 if p.mode == 0
0036     [F,V] = vb_reducepatch(F,V, Npatch); 
0037 end
0038 
0039 Nv = size(V,1);
0040 
0041 % get_shortest_path from source to detector along head
0042 [Xpath, Npath] = get_shortest_path(parm, facefile);
0043 
0044 % source & detector channel pos
0045 Npair = length(Npath);
0046 
0047 src_pos = zeros(Npair,3);
0048 det_pos = zeros(Npair,3);
0049 ch_pos  = zeros(Npair,3);
0050 
0051 for k=1:Npair
0052     Vpath = Xpath{k};
0053     
0054     src_pos(k,:) = Vpath(1,:);
0055     det_pos(k,:) = Vpath(end,:);
0056     
0057     % channel position: mid point
0058     N1 = max(fix( Npath(k)/2 ),1);
0059     ch_pos(k,:)  = Vpath(N1,:);
0060 end
0061 
0062 pos_mode = 1;
0063 %  dd = sq_distance(X,Y, pos_mode=1)
0064 %  X : (M x D) matrix
0065 %  Y : (N x D) matrix
0066 
0067 % max-min distance between probe & channel pos
0068 pos  = [src_pos; det_pos];
0069 dd   = sq_distance(pos, ch_pos, pos_mode);
0070 dmin = max(min(dd));
0071 
0072 % Select vertex for channel plot
0073 % DV(ch, id) = dist. of ch_pos(ch,:) & V(id,:)
0074 DV = sq_distance(ch_pos, V, pos_mode);
0075 dV = min(DV);
0076 
0077 ix = find(dV < dmin);
0078 
0079 % Select patch which include selected vertex points
0080 Vin  = V(ix,:);
0081 Fin  = vb_patch_select(ix,F,Nv);
0082 % Convert to vertex index within selected subset 'ix'
0083 Itrans = zeros(Nv,1);
0084 Itrans(ix) = 1:length(ix);
0085 Fin = Itrans(Fin);
0086 
0087 % Outer area
0088 iz = find(dV >= dmin);
0089 Fout = vb_patch_select2(iz,F,Nv);
0090 
0091 % --- Interpolation on face vertex using 3 neighbor channels
0092 %  W(n,1:3) : n-th interpolation coefficient
0093 % --- Interpolation using 'W'
0094 %  y(n,1:3) = Three data values corresponding to the distance dd(n,1:3)
0095 %  y_interp(n) = sum( W(n,1:3) .* y(n,1:3) , 2)
0096 
0097 % Find 3 neighbor channels for selected vertex Vin=V(ix,:)
0098 DV = DV(:,ix);
0099 [DV, Ich] = sort(DV);
0100 
0101 switch    p.mode
0102 case    0
0103     dn = sqrt(DV(1:3,:)');
0104     W  = vb_linear_interpolate3(dn);
0105     y  = sum( W .* ch_val(Ich(1:3,:)'), 2);
0106 case    1
0107     y  = ch_val(Ich(1,:)');
0108 end
0109 
0110 y = double(y);
0111 
0112 %
0113 % --- Plot channel data on face
0114 %
0115 h = figure;
0116 
0117 patch('Faces',Fin,'Vertices',Vin,'FaceColor','interp',...
0118     'FaceVertexCData',y,'EdgeColor','none',...
0119     'FaceLighting','none');
0120     
0121 %material dull;
0122 
0123 axis equal
0124 hold on;
0125 
0126 % Plot source & detector channel
0127 plot3(src_pos(:,1), src_pos(:,2), src_pos(:,3), p.Msend,'MarkerSize',p.Msize);
0128 plot3(det_pos(:,1), det_pos(:,2), det_pos(:,3), p.Mrecv,'MarkerSize',p.Msize);
0129 
0130 %
0131 % --- Plot outer surface
0132 vb_plot_surf(V,Fout);
0133 
0134 camlight headlight;