// points to something on a map
// needs to have an input element to reference 
// calling image
//<img type="image" src="http://image/button.jpg" onClick="setPointerPoint(-84.3345,42.3456,'this is a pointer')" />
// pointerpoint
//<img ID="pointerpoint" class="pointer_point" src="common/mapsymbols/pointerpoint.gif" title="" alt=""/>


function getLayerImageID(){return 'layerpoint';}

function getToggleLayerName(layername){return 'layertoggle_'+layername;}

function getToggleLayerValue(layername){

  var rc = '';
  var togglename = getToggleLayerName(layername.toLowerCase());
  var obj=null;
  try{
    obj = document.getElementById(togglename);
    if(!obj){throw togglename +" element is not available.";}
    rc=obj.value;
  }catch(err){
    alert("getToggleLayerValue " + err);
	rc = '0';
  }
  return rc; 
}

function setToggleLayerValue(layername){
 //alert('setToggleLayerValue');
  var rc = "";
 
  var togglename = getToggleLayerName(layername);

  rc = getToggleLayerValue(layername);
//alert('setToggleLayerValue togglename '+ togglename.toLowerCase());
  if(rc=='0'){
	document.getElementById(togglename).value='1';
  }else{
    document.getElementById(togglename).value='0';
  }
  rc = document.getElementById(togglename).value;

  return rc;

}

function getLayerPoint(pointname){
  var pnt;

  try{
    pnt = document.getElementById(pointname);
	if(!pnt){throw 'err';}
  } catch(err){alert('getLayerPoint: element '+pointname+' is not available');}

  return pnt;
}

function getLayerPointName(layername,i){
	//alert('getLayerPointName ');
	return "layerpoint_"+layername+i;
}

function setLayerPoint(layername,pointname,lon,lat,description){
//function setLayerPoint(pointname,lon,lat,description){


   var object_map = getMap(); 

   var point = getLayerPoint(pointname); 

   ///////////////
   // check toggle off
   if(getToggleLayerValue(layername)=='0'){
     setVisibility(point,false);
	 return ;
   }

   var img_x = parseInt(RX2BX( lon ,object_map));
   var img_y = parseInt(RY2BY( lat,object_map ));


   // set the point position
  
   point.style.left=img_x +'px';
   point.style.top=img_y +'px';
   point.title=description;

   // check if point is in or out of image area
   if(isInMap(point,object_map)){
     setVisibility(point,true);     
   }else{
     setVisibility(point,false);
   }

   return;
}

/////////////////////////
//  call after a click on the map or reposition
/////////////////////////
function refreshLayer(layername){
   try{
	  //alert('refresh ' +'getLayerPoints_'+layername+'();');
      eval('getLayerPoints_'+layername.toLowerCase()+'();');
   }catch(err){
	   alert(err);
     // no need for 
   }
}