wolffd@0: classdef Gvizlayout < Abstractlayout
wolffd@0: % Use the graphVIZ package to determine the optimal layout for a graph.
wolffd@0: %
wolffd@0: % Matthew Dunham
wolffd@0: % University of British Columbia 
wolffd@0: % http://www.cs.ubc.ca/~mdunham/
wolffd@0:    properties
wolffd@0:      xmin;               % The left most point on the graph axis in data units           
wolffd@0:      xmax;               % The right most point on the graph axis in data units
wolffd@0:      ymin;               % The bottom most point on the graph axis in data units
wolffd@0:      ymax;               % The top most point on the graph axis in data units
wolffd@0:      adjMatrix;          % The adjacency matrix
wolffd@0:      maxNodeSize;        % The maximum diameter of a node in data units
wolffd@0:      image;              % An image for the button that will lanuch this layout
wolffd@0:      name;               % A unique name for instances of this class. 
wolffd@0:      shortDescription;   % A short descriptions used in tooltips.
wolffd@0:      nodeSize;           % The calculated node size, call dolayout() before accessing
wolffd@0:      centers;            % The calculated node centers in an n-by-2 matrix
wolffd@0:    end
wolffd@0:     
wolffd@0:    properties(GetAccess = 'protected', SetAccess = 'protected')
wolffd@0:         layoutFile = 'layout.dot';
wolffd@0:         adjFile   =  'adjmat.dot';
wolffd@0:    end
wolffd@0:     
wolffd@0:    methods
wolffd@0:      
wolffd@0:        function obj = Gvizlayout(name)
wolffd@0:        % constructor
wolffd@0:             if(nargin < 1)
wolffd@0:                 obj.name = 'Gvizlayout';
wolffd@0:             else
wolffd@0:                 obj.name = name;
wolffd@0:             end
wolffd@0:             load glicons;
wolffd@0:             obj.image = icons.energy;
wolffd@0:             obj.shortDescription = 'Minimum Energy Layout (GraphViz)';
wolffd@0:        end
wolffd@0:        
wolffd@0:        function available = isavailable(obj)
wolffd@0:         % Make sure graphViz is available. 
wolffd@0:             available = Gvizlayout.queryGviz('neato');
wolffd@0:             if(not(available))
wolffd@0:                   fprintf('Please install or upgrade graphViz\n');
wolffd@0:             end
wolffd@0:         end
wolffd@0:        
wolffd@0:        
wolffd@0:    end
wolffd@0: 
wolffd@0:    
wolffd@0:    methods(Access = 'protected')
wolffd@0:        
wolffd@0:        function calcLayout(obj)
wolffd@0:        % Have graphViz calculate the layout
wolffd@0:           obj.writeDOTfile();
wolffd@0:           obj.callGraphViz();
wolffd@0:           obj.readLayout();
wolffd@0:           obj.cleanup();
wolffd@0:        end
wolffd@0:       
wolffd@0:        function writeDOTfile(obj)
wolffd@0:        % Write the adjacency matrix into a dot file that graphViz can
wolffd@0:        % understand. 
wolffd@0:             fid = fopen('adjmat.dot','w');
wolffd@0:             fprintf(fid,'digraph G {\ncenter = 1;\nsize="10,10";\n');
wolffd@0:             n = size(obj.adjMatrix,1);
wolffd@0:             for i=1:n, fprintf(fid,'%d;\n',i); end
wolffd@0:             edgetxt = ' -> ';
wolffd@0:             for i=1:n
wolffd@0:                 for j=1:n
wolffd@0:                    if(obj.adjMatrix(i,j))
wolffd@0:                       fprintf(fid,'%d%s%d;\n',i,edgetxt,j);
wolffd@0:                    end
wolffd@0:                 end 
wolffd@0:             end
wolffd@0:             fprintf(fid,'}');
wolffd@0:             fclose(fid);
wolffd@0:        end
wolffd@0:        
wolffd@0:        function callGraphViz(obj)
wolffd@0:        % Call GraphViz to determine an optimal layout. Write this layout in
wolffd@0:        % layout.dot for later parsing. 
wolffd@0:            err = system(['neato -Tdot -Gmaxiter=5000 -Gstart=7 -o ',obj.layoutFile,' ',obj.adjFile]);
wolffd@0:            if(err),error('Sorry, unknown GraphViz failure, try another layout'); end
wolffd@0:        end
wolffd@0:        
wolffd@0:        function readLayout(obj)
wolffd@0:        % Parse the layout.dot file for the graphViz node locations and 
wolffd@0:        % dimensions. 
wolffd@0:             fid = fopen(obj.layoutFile,'r');
wolffd@0:             text = textscan(fid,'%s','delimiter','\n'); 
wolffd@0:             fclose(fid);
wolffd@0:             text = text{:};
wolffd@0:             [start,dims] = strtok(text{cellfun(@(x)~isempty(x),strfind(text,'graph [bb="'))},'"');
wolffd@0:             dims = textscan(strtok(dims,'"'),'%n','delimiter',',');
wolffd@0:             dims = dims{:}';
wolffd@0:             text(cellfun(@(x)~isempty(x),strfind(text,' -> ')))=[]; % delete edge info, we don't need it
wolffd@0:             text(cellfun(@(x)isempty(x),strfind(text,'pos')))=[];   % keep only positions
wolffd@0:             [start,remaining] = strtok(text,'"');
wolffd@0:             [locations,remaining] = strtok(remaining,'"');
wolffd@0:             locations = cellfun(@(str)textscan(str,'%n','delimiter',','),locations,'UniformOutput',false);
wolffd@0:             locations = [locations{:}];
wolffd@0:             locations = [locations{:}]';
wolffd@0:             obj.scaleLocations(locations,dims);
wolffd@0:        end
wolffd@0:        
wolffd@0:        function scaleLocations(obj,locations,graphVizDims)
wolffd@0:        % Scale the graphViz node locations to the smartgraph dimensions and
wolffd@0:        % set the node size. 
wolffd@0:             dims = graphVizDims; loc = locations;
wolffd@0:             loc(:,1) = (loc(:,1)-dims(1)) ./ (dims(3)-dims(1))*(obj.xmax - obj.xmin) + obj.xmin;
wolffd@0:             loc(:,2) = (loc(:,2)-dims(2)) ./ (dims(4)-dims(2))*(obj.ymax - obj.ymin) + obj.ymin;
wolffd@0:             obj.centers = loc;
wolffd@0:             
wolffd@0:             a = min(abs(loc(:,1) - obj.xmin));
wolffd@0:             b = min(abs(loc(:,1) - obj.xmax));
wolffd@0:             c = min(abs(loc(:,2) - obj.ymin));
wolffd@0:             d = min(abs(loc(:,2) - obj.ymax));
wolffd@0:             obj.nodeSize = min(2*min([a,b,c,d]),obj.maxNodeSize);
wolffd@0:             
wolffd@0:        end
wolffd@0:        
wolffd@0:        function cleanup(obj)
wolffd@0:        % delete the temporary files. 
wolffd@0:            delete(obj.adjFile);
wolffd@0:            delete(obj.layoutFile);
wolffd@0:        end
wolffd@0:        
wolffd@0:    end
wolffd@0:   
wolffd@0:    methods(Access = 'protected',Static = true)
wolffd@0:       
wolffd@0:        function available = queryGviz(name)
wolffd@0:             err = system([name,' -V']);
wolffd@0:             available = ~err;
wolffd@0:        end
wolffd@0:        
wolffd@0:    end
wolffd@0:    
wolffd@0:  
wolffd@0: end % end of graphVIZlayout class