var ITEM_COUNT = 1;     //number of flakes visible per time
var ITEM_W = 200;        //width of a single flake
var ITEM_H = 30;        //height of a single flake
//var ITEM_SRC = "Afbeeldingen/feestdagen.gif";
var ITEM_STAGES = 1    //number of life stages for a single flake. (i.e., number of states on the "sterren.gif")
var ITEM_TRAVEL =100000;   //number of times to move a flake before disappearing (Note: PIXEL MOVED = ITEM_TRAVEL * ITEM_INCREMENT)
//var ITEM_INCREMENT = 1; //distance to move a flake on each loop (0 stilstaand, 1 bewegend)
var ITEM_SPEED = 1;    //time delay in milliseconds before looping (def: 40)

// END CONFIGURABLE CONSTANTS

var IE_ENGINE = (document.all) ? true : false;
var NS_ENGINE = (document.layers) ? true : false;

var animatorThread = null;

 // To prevent a new flake from being created 
 // on each loop time, we give it a sleep counter 
 // that increments.
var sprawnSleeping = 0;

 // Stores the position of mouse.
var mousePos = new Array(2);
mousePos[0] = 0;
mousePos[1] = 0;

  // Stores previous positions of mouse.
  // So that we don't create a flake when
  // the mouse hasn't moved.
var oldMousePos = new Array(2);
oldMousePos[0] = 0;
oldMousePos[1] = 0;

  // A table of flake positions and information.
var trailMatrix = new Array(ITEM_COUNT);
for(var i=0; i<trailMatrix.length; i++) {
  trailMatrix[i] = new Array(5);
  trailMatrix[i][0] = 0;
  trailMatrix[i][1] = 0;
  trailMatrix[i][2] = 0;
  trailMatrix[i][3] = ITEM_STAGES;
  trailMatrix[i][4] = "mouseTrailer_" + i;
  document.writeln((IE_ENGINE) ? '<DIV ID="' + trailMatrix[i][4] + '" STYLE="position:relative; width:'+ITEM_W+'px; height:'+ITEM_H+'px; visibility:hidden;"><img src="'+ITEM_SRC+'" border=0></DIV>' : (NS_ENGINE) ? '<LAYER ID="' + trailMatrix[i][4] + '" position="absolute" width='+ITEM_W+' height='+ITEM_H+' visible="hide"><img src="'+ITEM_SRC+'" border=0></LAYER>' : "");
}

function storeMousePos(e) {
  mousePos[0] =(IE_ENGINE) ? event.clientX+document.body.scrollLeft : (NS_ENGINE) ? e.pageX : 0;
  mousePos[1] =(IE_ENGINE) ? event.clientY+document.body.scrollTop : (NS_ENGINE) ? e.pageY : 0;
}

function sprawnNewTrail() {
  if(oldMousePos[0] != mousePos[0] || oldMousePos[1] != mousePos[1]) {
    var temp = trailMatrix[trailMatrix.length-1][4];
    for(var i=trailMatrix.length-1; i>0; i--) {
      trailMatrix[i][0] = trailMatrix[i-1][0];
      trailMatrix[i][1] = trailMatrix[i-1][1];
      trailMatrix[i][2] = trailMatrix[i-1][2];
      trailMatrix[i][3] = trailMatrix[i-1][3];
      trailMatrix[i][4] = trailMatrix[i-1][4];}
    trailMatrix[0][0] = mousePos[0];
    trailMatrix[0][1] = mousePos[1];
    trailMatrix[0][2] = ITEM_TRAVEL;
    trailMatrix[0][3] = ITEM_STAGES;
    trailMatrix[0][4] = temp;  //id for trailer layer
  }
  oldMousePos[0] = mousePos[0];
  oldMousePos[1] = mousePos[1];}

function animateTrail() {
  for(var i=0; i<trailMatrix.length; i++) {
    if(trailMatrix[i][2] > 0) {
      trailMatrix[i][1] += ITEM_INCREMENT;
      trailMatrix[i][2]--;
      trailMatrix[i][3] = Math.ceil((trailMatrix[i][2] * ITEM_STAGES) / ITEM_TRAVEL);
      updateTrail(trailMatrix[i][4], trailMatrix[i][0], trailMatrix[i][1], trailMatrix[i][3]);
    } else {
      hideTrail(trailMatrix[i][4]);}}
  sprawnSleeping++;
  if(sprawnSleeping >= 2) {  //We create a new flake every 2 loops
    sprawnSleeping = 0;
    sprawnNewTrail();}}

function updateTrail(obj, x, y, stage) {
  var imgTop = (ITEM_STAGES - stage) * ITEM_H;
  if(IE_ENGINE) {
    document.all[obj].style.clip = "rect("+imgTop +" "+ ITEM_W +" "+ (imgTop+ITEM_H)+" 0)";
    document.all[obj].style.left = x;
    document.all[obj].style.top = y - imgTop;
    document.all[obj].style.visibility = "visible";
  } else if(NS_ENGINE) {
    document.layers[obj].clip.top = imgTop;
    document.layers[obj].clip.bottom = imgTop + ITEM_H;
    document.layers[obj].left = x;
    document.layers[obj].top = y - imgTop;
    document.layers[obj].visibility = "show";}}

function hideTrail(obj) {
  if(IE_ENGINE) {
    document.all[obj].style.visibility = "hidden";
  } else if(NS_ENGINE) {
    document.layers[obj].visibility = "hide";}}

function init() {
  if(NS_ENGINE)document.captureEvents(Event.MOUSEMOVE);
  if(IE_ENGINE || NS_ENGINE) {
    document.onmousemove = storeMousePos;
    animatorThread = setInterval("animateTrail()", ITEM_SPEED);}}

function endend() {
  if(animatorThread != null) {
    clearInterval(animatorThread);
    animatorThread = null;}}