EXTERNPROTO        pointer[
          eventIn        SFFloat        transparency
  ]"models/buttonBar/back/back_forward_button.wrl#ModelBackForwardNode"
  
  PROTO History[
          eventIn        SFString nodeIn
          eventIn        SFFloat endTransparencyButton
          eventOut SFString nodeOut
          eventOut SFBool show
          eventOut SFBool        ready
  ]
  {
  DEF        SW Switch {
                  whichChoice        0
                  choice [
          Transform {
                  scale 0.9 0.9 0.9
                  translation        -0.1 0 0
                  rotation 0 0 1 3.14
                  children [
                  
                          DEF pointer pointer        {
                                  
                          }
                          DEF touch TouchSensor{}
                  ]
          }
  ]
  }
  
          DEF script Script {
                  directOutput TRUE
                  eventOut SFBool        show IS        show
                  eventOut SFString nodeOut IS nodeOut
                  eventIn        SFString nodeIn IS nodeIn
                  eventOut SFBool        ready IS ready
                  eventIn        SFBool clicked
                  field MFNode history []
                  field SFInt32 current -1
                  field SFBool goingBack FALSE
  
                  url "javascript:
  
                  function initialize()
                  {
                          ready=true;
                  }
                          
                  function clicked(value)
                  {
                          if(value)
                          {
                                  if(current>0) // only react if there have been 2 clicks (start value of current = 2)
                                                            // the first click is for opening the main node the second is the first real step
                                  {
                                          goingBack = true;
                                          nodeOut = history[current-1].nodes;
                                          current-=2;
                                          show =true;
                                  }
                          }
                  }
  
                  function nodeIn(value)
                  {
                          if (current < 0 || history[current].nodes != value) { // always add the first clicked node, do not add the same node twice
                                  goingBack = false;
                                  current++;
                                  history[current] =Browser.createVrmlFromString('PROTO Nodes[field SFString nodes \"\"]{} Nodes{}')[0];
                                  history[current].nodes = value;
                          }
                  }
                  "
  
          
          }
  
          DEF        historyButtonScript Script {
                  eventIn        SFBool rollOver
                  eventIn SFTime time
                  eventIn        SFFloat        setTransparency IS endTransparencyButton
                  field SFFloat beginTransparency 0
                  eventOut SFFloat transparency
                  field SFTime beginTimeTransparency 0
                  field SFBool transparencyEffectEnabled FALSE
                  field SFFloat totalTimeTransparency 2
                  eventOut SFInt32 whichchoice
              eventOut MFString rollOverText 
  
                  url        "javascript:
                  function initialize() {
                          transparency = beginTransparency;
                  }
  
                  // transparency effect: see buttonbar.wrl for description
                  function time(value) {
                          if (transparencyEffectEnabled) {
                                  var factor = (value - beginTimeTransparency) / totalTimeTransparency;
                                  if (factor < 1) {
                                          transparency = factor * (setTransparency - beginTransparency) + beginTransparency;
                                  } else {
                                          transparency = setTransparency;
                                          transparencyEffectEnabled = false;
                                          if (setTransparency == 1) whichchoice = -1;
  
                                  }
                          }
                  }
  
                  function setTransparency (value,time) {
                          //print('transparantie is: ');
                          whichchoice = 0;
                          beginTimeTransparency = time;
                          beginTransparency = transparency;
                          transparencyEffectEnabled = true;
                  }
  
                  function rollOver(value){
                          if (value){
                                  //print('rollOver is true');
                           rollOverText = 'back';
                                   
                          }
                          else{
                           rollOverText = '';
                           //print('rollOver is false');
                          }
  
                  }
  
                  "
          }
  
          DEF rollOverHistoryText Transform { # rollover text for the back button
                  translation        0 0 0
                  children [
                          Shape {
                                  geometry DEF rolloverHistoryText Text {  
                                   string        ""
                                  }
                          }
                  
                  ]        
          }
  
          DEF        Timer TimeSensor {
          loop TRUE
          enabled        TRUE
  }
          ROUTE touch.isOver TO historyButtonScript.rollOver
          ROUTE historyButtonScript.rollOverText TO rolloverHistoryText.string
  
          ROUTE  touch.isActive TO script.clicked
          ROUTE historyButtonScript.whichchoice TO SW.whichChoice
          ROUTE Timer.time TO        historyButtonScript.time
          ROUTE historyButtonScript.transparency TO pointer.transparency
  
  }
  
  History        {}