findGridConnectivity

clear;
data = [ 475.  ,  605.75,    1.;
    571.  ,  586.5 ,    2.;
    233.  ,  558.5 ,    3.;
    669.5 ,  562.75,    4.;
    291.25,  546.25,    5.;
    759.  ,  536.25,    6.;
    362.5 ,  531.5 ,    7.;
    448.  ,  513.5 ,    8.;
    834.5 ,  510.  ,    9.;
    897.25,  486.  ,   10.;
    545.5 ,  491.25,   11.;
    214.5 ,  481.25,   12.;
    271.25,  463.  ,   13.;
    646.5 ,  466.75,   14.;
    739.  ,  442.75,   15.;
    340.5 ,  441.5 ,   16.;
    817.75,  421.5 ,   17.;
    423.75,  417.75,   18.;
    202.5 ,  406.  ,   19.;
    519.25,  392.25,   20.;
    257.5 ,  382.  ,   21.;
    619.25,  368.5 ,   22.;
    148.  ,  359.75,   23.;
    324.5 ,  356.  ,   24.;
    713.  ,  347.75,   25.;
    195.  ,  335.  ,   26.;
    793.5 ,  332.5 ,   27.;
    403.75,  328.  ,   28.;
    249.25,  308.  ,   29.;
    495.5 ,  300.75,   30.;
    314.  ,  279.  ,   31.;
    764.25,  249.5 ,   32.;
    389.5 ,  249.5 ,   33.;
    475.  ,  221.5 ,   34.;
    565.75,  199.  ,   35.;
    802.75,  173.75,   36.;
    733.  ,  176.25,   37.];

X = data(:,1:2);X(:,2) = -X(:,2);


dt = delaunayTriangulation(X);
bd = dt.freeBoundary;
bdNodes = unique(bd);
bdconnectivity = knnsearch(X,X(bdNodes,:),'K',3);
interiorconnectivity = knnsearch(X,X(setdiff(1:size(X,1),bdNodes),:),'K',5);

clf;
plot(X(:,1),X(:,2),'xr');
hold on;
for i = 1:size(interiorconnectivity,1)
    for j = 2:5
    plot(X(interiorconnectivity(i,[1,j]),1),...
         X(interiorconnectivity(i,[1,j]),2));
    end
end
for i = 1:size(bdconnectivity,1)
    for j = 2:3
    plot(X(bdconnectivity(i,[1,j]),1),...
         X(bdconnectivity(i,[1,j]),2));
    end
end

axis equal