plotTrafficFlow (nodesPlaceMatrix, edgeTable, flowID, flowTable, flowRoutingMatrix, topologyTitle)

% plotTrafficFlow
% 
%>> Usage:      plotTrafficFlow (nodesPlaceMatrix, edgeTable, flowID,
%flowTable, flowRoutingMatrix, topologyTitle)
%
%>> Abstract:   This function draws the component of traffic in an edge due to the pair of nodes <flowOrigin, flowDestination> 
%               over the network topology. We call partial flow to this component of traffic. The network topology of nodes and 
%               edges is done by mean of the positions of nodes and the matrix of edges information. In this representation it is   
%               not assumed bidirectional edges between each node pair and the edges are represented by means of arrows.
%              
%>> Arguments:
%   o In: 
%     nodesPlaceMatrix(Nx2): XY coordinates of nodes, where N is the number of nodes. 
%      They are contained in the first and second column respectively.
%
%    . edgeTable(M,2): M-by-2 integer matrix. Each row is an edge (physical link 
%      or lightpath) 'm', where the first and second columns of each row are the 
%      origin node 'x' and destination node 'y' of this edge 'm' respectively and
%      M is the number of physical links or lightpaths if the network topology
%      is physical or virtual respectively.
%
%     flowID(1x1): Identifier of the flow to plot
%
%   . flowTable(F,6): F-by-6 integer matrix where F is the number of flows.
%     Each row is a flow 'f', where the first column is the serial number of the
%     flow, the second column is the source node 's', the third column is the 
%     destination node 'd', the fourth column is the  traffic flow from 
%     node 's' to node 'd', the fifth column is the initial time of the flow, and the 
%     sixth column is the total duration of the flow. 
%
%   . flowRoutingMatrix (F,L): F-by-L integer matrix where F is the number of 
%     flows and L is the number of lightpaths. Each row is a flow 'f' and each 
%     column is a lightpath 'l'. If a flow 'f' uses a lightpath 'l', the entry
%     (f,l) is equal to the value of the flow 'f' carried by the lightpath 'l'. If no 
%     lightpath is used by the flow 'f', the entry is equal to '0'. 
%
%     topologyTitle:  Title of the plot.
%
function plotTrafficFlow (nodesPlaceMatrix, edgeTable, flowID, flowTable, flowRoutingMatrix, topologyTitle)

if (nargin==0),  help plotTrafficFlow;return, end %help calling
if (nargin~=6),  error('1: Incorrect number of arguments.'),end %Number of input arguments different of 6
if(size(nodesPlaceMatrix,2)~=2), error('2: Argument "nodePlaceMatrix" must have two columns'), end

backgroundScaleX = abs(max(nodesPlaceMatrix(:,1)) - min(nodesPlaceMatrix(:,1)));
backgroundScaleY = abs(max(nodesPlaceMatrix(:,2)) - min(nodesPlaceMatrix(:,2)));
textOffset = 0.03;

%All nodes are drawn 
plot(nodesPlaceMatrix(:,1),nodesPlaceMatrix(:,2),'bo','MarkerSize',10,'Color',[1 0.41 0],'LineWidth',2.0,'MarkerFaceColor',[1 0.41 0]);
%The axis are fixed in both dimensions according to minimum and maximum values of nodesPlaceMatrix
axis([min(min(nodesPlaceMatrix(:,1)))-backgroundScaleX*0.01 max(max(nodesPlaceMatrix(:,1)))+backgroundScaleX*0.01 min(min(nodesPlaceMatrix(:,2)))-backgroundScaleY*0.01 max(max(nodesPlaceMatrix(:,2)))+backgroundScaleY*0.1],'manual','off');

%We draw the virtual topology .With a virtual topology, we are drawing an arrow diagram (lightpath network)
H=title(topologyTitle,'FontSize',8,'Fontweight','light','FontName','Verdana','HorizontalAlignment','Center','VerticalAlignment','Baseline');
aux=get(H,'Position');
for m=1:size(edgeTable,1),
%     line([nodesPlaceMatrix(edgeTable(m,1),1) nodesPlaceMatrix(edgeTable(m,2),1)],[nodesPlaceMatrix(edgeTable(m,1),2) nodesPlaceMatrix(edgeTable(m,2),2)],'color',[1 0.4 0],'lineWidth',1);
      arrow(line([nodesPlaceMatrix(edgeTable(m,1),1) nodesPlaceMatrix(edgeTable(m,2),1)],[nodesPlaceMatrix(edgeTable(m,1),2) nodesPlaceMatrix(edgeTable(m,2),2)],'color',[0 0 0.52],'lineWidth',1),'Length',19,'BaseAngle',90,'TipAngle',5,'Width',0,'FaceColor',[0 0 0.52]);
end

%We draw the traffic flow with identifier "flowID". We are drawing an arrow diagram.
flowEdges=find(flowRoutingMatrix(flowID,:)>0);

for i=1:length(flowEdges),
    arrow(line([nodesPlaceMatrix(edgeTable(flowEdges(i),1),1) nodesPlaceMatrix(edgeTable(flowEdges(i),2),1)],[nodesPlaceMatrix(edgeTable(flowEdges(i),1),2) nodesPlaceMatrix(edgeTable(flowEdges(i),2),2)],'color',[0 0.6 0.2],'lineWidth',2),'Length',19,'BaseAngle',90,'TipAngle',10,'Width',0,'FaceColor',[0 0.6 0.2]);
    
    %The distances between source and destination node pair in
    %both dimensions are necessary
    distanceX=nodesPlaceMatrix(edgeTable(flowEdges(i),2),1) - nodesPlaceMatrix(edgeTable(flowEdges(i),1),1);
    distanceY=nodesPlaceMatrix(edgeTable(flowEdges(i),2),2) - nodesPlaceMatrix(edgeTable(flowEdges(i),1),2);
       
    colour=[0 0 0];
    textLabel={[num2str( flowRoutingMatrix(flowID,flowEdges(i))  )],['%F:',num2str( 100* flowRoutingMatrix(flowID,flowEdges(i))./ flowTable(flowID,4))],...
   ['%U:',num2str( 100* flowRoutingMatrix(flowID,flowEdges(i))./ sum(flowRoutingMatrix(:,flowEdges(i))) )]};

    %Text labels are set according to the relative node pairs position
    distanceVector = [distanceX distanceY 0];
    normalVectorToDistanceVector = cross(distanceVector/norm(distanceVector) , [0 0 1]);
    text(nodesPlaceMatrix(edgeTable(flowEdges(i),2),1)-distanceX/3+textOffset*backgroundScaleX*normalVectorToDistanceVector(1), nodesPlaceMatrix(edgeTable(flowEdges(i),2),2)-distanceY/3+textOffset*backgroundScaleY*normalVectorToDistanceVector(2) , textLabel,'color',colour,'FontSize',8,'FontWeight','bold');
end
                       
%At the end, text label of each node is set
for i=1:length(nodesPlaceMatrix)
    text(nodesPlaceMatrix(i,1),nodesPlaceMatrix(i,2),{int2str(i)},'FontSize',6,'Color',[1 1 1],'HorizontalAlignment','Center');
end