title: How to get count of cars in specific range
body: <p>In veins i'm trying to simulate a VANET scenario in which if road is blocked then after specific time the car broadcast a message including blocked roadId and count of vehicles around it's 100 meter.</p>
  
  <p>In TraCIDemo11p application when the car is stopped for longer than 10 seconds it changes the node color to red (to show an accident) and sends a message out to other cars containing the blocked road id, all this is done in handlePositionUpdate mehtod:</p>
  
  <pre><code>findHost()-&gt;getDisplayString().updateWith("r=16,red");
  sentMessage = true;
  
  WaveShortMessage* wsm = new WaveShortMessage();
  populateWSM(wsm);
  wsm-&gt;setWsmData(mobility-&gt;getRoadId().c_str());
  
  //host is standing still due to crash
  if (dataOnSch) {
      startService(Channels::SCH2, 42, "Traffic Information Service");
      //started service and server advertising, schedule message to self to send later
      scheduleAt(computeAsynchronousSendingTime(1,type_SCH),wsm);
  }
  else {
      //send right away on CCH, because channel switching is disabled
      sendDown(wsm);
  }
  </code></pre>
  
  <p>The limit of 100m can be set by updating maxInterfDist value in in .ini file</p>
  
  <pre><code>*.connectionManager.maxInterfDist = 100m
  </code></pre>
  
  <p>Now the problem I have is how to get the count of vehicles and 100m of area, I have an idea that this will be done using TraCI and most probably using <a href="http://www.sumo.dlr.de/userdoc/TraCI/Lane_Area_Detector_Value_Retrieval.html" rel="nofollow noreferrer">LaneAreaDetector's getJamLengthVehicle</a> but i'm not getting how this will be done in veins, is their any equivalent method or i'm looking in wrong direction?</p>