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