gfx.cpp

传感器网络的可靠路由算法

#include "stdafx.h"
#include "Network.h"
#include "GFX.h"

/* global variables */
extern NODE_TYPE nodeT[4000];
extern NETWORK_TYPE net;

int bestNeighborX(int from,int dest);

void BuildGFX(int root){

	int i;
	for( i = 0 ; i < net.NUM_NODES;i++){
	 int next = bestNeighborX(i,root);
	 if(next != INVALID_ID)
	   SetNextHop(i, root, next);
	}	
}

int bestNeighborX(int from,int dest) //gfX
{
 int i;
 int to;
 bool found = false;
 double test = -1;
 int find;
 double currenttest;
 
 assert(from < net.NUM_NODES && dest < net.NUM_NODES);

 if(from == dest) return from;

 for (i=0;i<nodeT[from].neighbornum;i++) 
 {

//	 printf("%d\n",i);
   if ((unidirectional(from, nodeT[from].neighbor[i])==true))
	   continue;
   
   if(adistance(nodeT[from].neighbor[i],dest) > adistance(from,dest)) continue;


   to = nodeT[from].neighbor[i]; 
   double a,b,c;
		  a = adistance(from, to);
		  b = adistance(from, dest);
		  c = adistance(to,dest);
		
		
		  if((b-c) < 0) continue;
		  
		  if (b>c)
		  /* to discuss */
	     currenttest = (b-c) * linkquality(from,to);

         if (currenttest  > test)
		 {		test = currenttest;
		        find = nodeT[from].neighbor[i];
		        found = true;
	     }   
 }

 if (found == false){
	 printf("node %d can not do greedy forward\n",from);
	 find = INVALID_ID;
	 assert(false);
 }
  // printf("%d->%d\n",from,find);

  return find;
}