Code viewer for World: Halloween A*
// Cloned by Deborah Djon on 31 Oct 2022 from World "Complex World" by Starter user 
// Please leave this clone trail here.
 



// ==== Starter World =================================================================================================
// This code is designed for use on the Ancient Brain site.
// This code may be freely copied and edited by anyone on the Ancient Brain site.
// To include a working run of this program on another site, see the "Embed code" links provided on Ancient Brain.
// ====================================================================================================================



// =============================================================================================
// More complex starter World 
// 3d-effect Maze World (really a 2-D problem)
// Movement is on a semi-visible grid of squares 
//
// This more complex World shows:
// - Skybox
// - Internal maze (randomly drawn each time)
// - Enemy actively chases agent
// - Music/audio
// - 2D world (clone this and set show3d = false)
// - User keyboard control (clone this and comment out Mind actions to see)
// =============================================================================================


// =============================================================================================
// Scoring:
// Bad steps = steps where enemy is within one step of agent.
// Good steps = steps where enemy is further away. 
// Score = good steps as percentage of all steps.
//
// There are situations where agent is trapped and cannot move.
// If this happens, you score zero.
// =============================================================================================


 





// ===================================================================================================================
// === Start of tweaker's box ======================================================================================== 
// ===================================================================================================================

// The easiest things to modify are in this box.
// You should be able to change things in this box without being a JavaScript programmer.
// Go ahead and change some of these. What's the worst that could happen?


AB.clockTick       = 150; // 150;    

	// Speed of run: Step every n milliseconds. Default 100.
	
AB.maxSteps        = 1000;    

	// Length of run: Maximum length of run in steps. Default 1000.

AB.screenshotStep  = 50;   
  
	// Take screenshot on this step. (All resources should have finished loading.) Default 50.



//---- global constants: -------------------------------------------------------

	const show3d = true;						// Switch between 3d and 2d view (both using Three.js) 


 const TEXTURE_WALL 	= '/uploads/starter/door.jpg' ;
 const TEXTURE_MAZE 	= '/uploads/starter/latin.jpg' ;
 const TEXTURE_AGENT 	= '/uploads/starter/pacman.jpg' ;
 const TEXTURE_ENEMY 	= '/uploads/starter/ghost.3.png' ;
 const GROUND_GRID = '/uploads/tharealog/grid6.png';
 const GROUND_DISPLACEMENT = '/uploads/tharealog/displacement.png';

// credits:
// http://commons.wikimedia.org/wiki/File:Old_door_handles.jpg
// https://commons.wikimedia.org/wiki/Category:Pac-Man_icons
// https://commons.wikimedia.org/wiki/Category:Skull_and_crossbone_icons
// http://en.wikipedia.org/wiki/File:Inscription_displaying_apices_(from_the_shrine_of_the_Augustales_at_Herculaneum).jpg

 
    //source: Music by <a href="https://pixabay.com/users/geoffharvey-9096471/?utm_source=link-attribution&amp;utm_medium=referral&amp;utm_campaign=music&amp;utm_content=122118">geoffharvey</a> from <a href="https://pixabay.com/music//?utm_source=link-attribution&amp;utm_medium=referral&amp;utm_campaign=music&amp;utm_content=122118">Pixabay</a>
	const MUSIC_BACK  = '/uploads/tharealog/let-the-mystery-unfold-122118.mp3' ;
	
	const SOUND_ALARM = '/uploads/tharealog/evil_laugh.mp3' ;

// credits:
// http://www.dl-sounds.com/royalty-free/defense-line/
// http://soundbible.com/1542-Air-Horn.html 

	
	
const gridsize = 35;						// number of squares along side of world	   

const NOBOXES =  Math.trunc ( (gridsize * gridsize) / 7 );  // 7
		// density of maze - number of internal boxes
		// (bug) use trunc or can get a non-integer 

const squaresize = 100;					// size of square in pixels

const MAXPOS = gridsize * squaresize;		// length of one side in pixels 
	
const SKYCOLOR 	= 0xddffdd;				// a number, not a string 

 
const startRadiusConst	 	= MAXPOS * 0.8 ;		// distance from centre to start the camera at
const maxRadiusConst 		= MAXPOS * 10  ;		// maximum distance from camera we will render things  


//--- change ABWorld defaults: -------------------------------

ABHandler.MAXCAMERAPOS 	= maxRadiusConst ;

ABHandler.GROUNDZERO		= true;						// "ground" exists at altitude zero



//--- skybox: -------------------------------
// skybox is a collection of 6 files 
// x,y,z positive and negative faces have to be in certain order in the array 
// https://threejs.org/docs/#api/en/loaders/CubeTextureLoader 

// mountain skybox, credit:
// http://stemkoski.github.io/Three.js/Skybox.html

/* altered by deborah djon:
I made my own sky box with a vaporwave backgound made from: https://www.artstation.com/artwork/oO0O0J
*/ 
 const SKYBOX_ARRAY = [										 
                "uploads/tharealog/sb11.png",
                "uploads/tharealog/sb31.png",
                "uploads/tharealog/sb_top1.png",
                "uploads/tharealog/sb_top1.png",
                "uploads/tharealog/sb41.png",
                "uploads/tharealog/sb21.png",
                ];

// ===================================================================================================================
// === End of tweaker's box ==========================================================================================
// ===================================================================================================================


// You will need to be some sort of JavaScript programmer to change things below the tweaker's box.









//--- Mind can pick one of these actions -----------------

const ACTION_LEFT 			= 0;		   
const ACTION_RIGHT 			= 1;
const ACTION_UP 			= 2;		 
const ACTION_DOWN 			= 3;
const ACTION_STAYSTILL 		= 4;

// in initial view, (smaller-larger) on i axis is aligned with (left-right)
// in initial view, (smaller-larger) on j axis is aligned with (away from you - towards you)


// contents of a grid square

const GRID_BLANK 	= 0;
const GRID_WALL 	= 1;
const GRID_MAZE 	= 2;
 
 
 


var BOXHEIGHT;		// 3d or 2d box height 

var GRID 	= new Array(gridsize);			// can query GRID about whether squares are occupied, will in fact be initialised as a 2D array   
let mazeBoxes = []; //deborah

var theagent, theenemy;
  
var wall_texture, agent_texture, enemy_texture, maze_texture; 


// enemy and agent position on squares
var ei, ej, ai, aj;

var badsteps;
var goodsteps;


	
function loadResources()		// asynchronous file loads - call initScene() when all finished 
{
	var loader1 = new THREE.TextureLoader();
	var loader2 = new THREE.TextureLoader();
	var loader3 = new THREE.TextureLoader();
	var loader4 = new THREE.TextureLoader();
	
	loader1.load ( TEXTURE_WALL, function ( thetexture )  		
	{
		thetexture.minFilter  = THREE.LinearFilter;
		wall_texture = thetexture;
		if ( asynchFinished() )	initScene();		// if all file loads have returned 
	});
		
	loader2.load ( TEXTURE_AGENT, function ( thetexture )  	 
	{
		thetexture.minFilter  = THREE.LinearFilter;
		agent_texture = thetexture;
		if ( asynchFinished() )	initScene();		 
	});	
	
	loader3.load ( TEXTURE_ENEMY, function ( thetexture )  
	{
		thetexture.minFilter  = THREE.LinearFilter;
		enemy_texture = thetexture;
		if ( asynchFinished() )	initScene();		 
	});
	
	loader4.load ( TEXTURE_MAZE, function ( thetexture )  
	{
		thetexture.minFilter  = THREE.LinearFilter;
		maze_texture = thetexture;
		if ( asynchFinished() )	initScene();		 
	});
	
}


function asynchFinished()		 // all file loads returned 
{
	if ( wall_texture && agent_texture && enemy_texture && maze_texture )   return true; 
	else return false;
}	
	
	
 

//--- grid system -------------------------------------------------------------------------------
// my numbering is 0 to gridsize-1

	
function occupied ( i, j )		// is this square occupied
{
 if ( ( ei == i ) && ( ej == j ) ) return true;		// variable objects 
 if ( ( ai == i ) && ( aj == j ) ) return true;

 if ( GRID[i][j] == GRID_WALL ) return true;		// fixed objects	 
 if ( GRID[i][j] == GRID_MAZE ) return true;		 
	 
 return false;
}

 
// translate my (i,j) grid coordinates to three.js (x,y,z) coordinates
// logically, coordinates are: y=0, x and z all positive (no negative)    
// logically my dimensions are all positive 0 to MAXPOS
// to centre everything on origin, subtract (MAXPOS/2) from all dimensions 

function translate ( i, j )			
{
	var v = new THREE.Vector3();
	
	v.y = 0;	
	v.x = ( i * squaresize ) - ( MAXPOS/2 );   		 
	v.z = ( j * squaresize ) - ( MAXPOS/2 );   	
	
	return v;
}



	
function initScene()		// all file loads have returned 
{
	 var i,j, shape, thecube;
	 
	// set up GRID as 2D array
	 
	 for ( i = 0; i < gridsize ; i++ ) 
		GRID[i] = new Array(gridsize);		 


	// set up walls
	
	/*
	altered by deborah djon:
	
	changed the walls to be a wireframw and, hence, seethrough. 
	Box height is reduced to half the boxheight. 
	*/
	 
	 for ( i = 0; i < gridsize ; i++ ) 
	  for ( j = 0; j < gridsize ; j++ ) 
		if ( ( i==0 ) || ( i==gridsize-1 ) || ( j==0 ) || ( j==gridsize-1 ) )
		{

			GRID[i][j] = GRID_WALL;		 
			shape    = new THREE.BoxGeometry ( squaresize, BOXHEIGHT/2, squaresize );	
			
		    wireframe = new THREE.WireframeGeometry( shape );
		
		    lineMaterial = new THREE.LineBasicMaterial( { color: 'red' } );
		   
		    thecube = new THREE.LineSegments( wireframe , lineMaterial); 
            thecube.material.transpaent = true;
		    thecube.material.opacity = 0.01;
			
			thecube.position.copy ( translate(i,j) ); 		  	// translate my (i,j) grid coordinates to three.js (x,y,z) coordinates 
			ABWorld.scene.add(thecube);
		}
		else 
   			GRID[i][j] = GRID_BLANK;

		
   // set up maze 
   
   /*
   altered by deborah djon:
   The style of the boxes is changed to be pyramids. 
   The color and material of the pyramids is changed to be a plain red. 
   In additoin references to the created walls are saved in an array, so 
   they can be moved later.
   */
   
    for ( var c=1 ; c <= NOBOXES ; c++ )
	{
		i = AB.randomIntAtoB(1,gridsize-2);		// inner squares are 1 to gridsize-2
		j = AB.randomIntAtoB(1,gridsize-2);
			
		GRID[i][j] = GRID_MAZE ;
		
		r = squaresize/2+20;
		h = BOXHEIGHT; 
		geo = new THREE.CylinderGeometry(0, r, h, 4, 1);
		material = new THREE.MeshPhongMaterial( { color: 'red'} );
		pyramidMesh = new THREE.Mesh( geo, material );
		// add blak outline to the pyramids
        mat = new THREE.LineBasicMaterial( { color: 'black' } );
        wireframe = new THREE.LineSegments( geo, mat );
        pyramidMesh.add( wireframe );
	    
	    // rotate the pyramids they start out slightly sideways
        pyramidMesh.rotation.y = -Math.PI * 0.25;
		pyramidMesh.position.copy ( translate(i,j) );
		mazeBoxes.push(pyramidMesh);
		ABWorld.scene.add(pyramidMesh);	
	}
	 	 
   
	// set up enemy 
	// start in random location
	
	 do
	 {
	  i = AB.randomIntAtoB(1,gridsize-2);
	  j = AB.randomIntAtoB(1,gridsize-2);
	 }
	 while ( occupied(i,j) );  	  // search for empty square 

	 ei = i;
	 ej = j;
	 
	 //shape    = new THREE.BoxGeometry ( squaresize, BOXHEIGHT, squaresize );
	 shape = new THREE.SphereGeometry( squaresize*0.9, 32, 16 );
	 theenemy = new THREE.Mesh( shape );
 	 theenemy.material =  new THREE.MeshBasicMaterial( { map: enemy_texture } );
	 ABWorld.scene.add(theenemy);
	 drawEnemy();		  

	 
	
	// set up agent 
	// start in random location
	
	 do
	 {
	  i = AB.randomIntAtoB(1,gridsize-2);
	  j = AB.randomIntAtoB(1,gridsize-2);
	 }
	 while ( occupied(i,j) );  	  // search for empty square 

	 ai = i;
	 aj = j;
 
	 //shape    = new THREE.BoxGeometry ( squaresize, BOXHEIGHT, squaresize );	
	 shape = new THREE.SphereGeometry( squaresize/3, 32, 16 );
	 theagent = new THREE.Mesh( shape );
	 theagent.material =  new THREE.MeshBasicMaterial( { color: 'white' } );
	 ABWorld.scene.add(theagent);
	 drawAgent(); 

    /*altered by Deborah Djon
    Added a 3D mountain landscape to the scene
    This is done by creating a plane with a grid pattern, then using a displacement
    texture
    source: https://res.cloudinary.com/dg5nsedzw/image/upload/v1641657200/blog/vaporwave-threejs-textures/displacement.png
    source: https://blog.maximeheckel.com/posts/vaporwave-3d-scene-with-threejs/
    */

    const textureLoader = new THREE.TextureLoader();
    const gridTexture = textureLoader.load(GROUND_GRID);
    const terrainTexture = textureLoader.load(GROUND_DISPLACEMENT);

    floorSize = 30000
    const geometry = new THREE.PlaneGeometry(floorSize, floorSize, 64,64);

    material = new THREE.MeshStandardMaterial({
        map: gridTexture,
        displacementMap: terrainTexture,
        displacementScale: 25000,
    })

    	 
    const plane = new THREE.Mesh(geometry, material);
    plane.position.copy( translate(17,17) );
    
    adjust = 0;
    plane.position.x += adjust
    plane.position.y += adjust
    plane.position.y = - BOXHEIGHT/2;

    plane.rotation.x = -Math.PI * 0.5;

    ABWorld.scene.add(plane)
    
    const pointLight = new THREE.PointLight('red',2);
    pointLight.position.copy( translate(10,10) )
    pointLight.position.y = squaresize*20
    ABWorld.scene.add(pointLight)
    

   
//---------------------------


  // finally skybox 
  // setting up skybox is simple 
  // just pass it array of 6 URLs and it does the asych load 
  
  	 ABWorld.scene.background = new THREE.CubeTextureLoader().load ( SKYBOX_ARRAY, 	function() 
	 { 
		ABWorld.render(); 
	 
		AB.removeLoading();
	
		AB.runReady = true; 		// start the run loop
	 });
	 

}
 
 
 


// --- draw moving objects -----------------------------------


function drawEnemy()		// given ei, ej, draw it 
{
	theenemy.position.copy ( translate(ei,ej) ); 		  	// translate my (i,j) grid coordinates to three.js (x,y,z) coordinates 

	ABWorld.lookat.copy ( theenemy.position );	 		// if camera moving, look back at where the enemy is  
}


function drawAgent()		// given ai, aj, draw it 
{
	theagent.position.copy ( translate(ai,aj) ); 		  	// translate my (i,j) grid coordinates to three.js (x,y,z) coordinates 

	ABWorld.follow.copy ( theagent.position );			// follow vector = agent position (for camera following agent)
}




// --- take actions -----------------------------------

function moveLogicalEnemy()
{ 
// move towards agent 
// put some randomness in so it won't get stuck with barriers 
 calculateAStarPath();
 console.log("calculated A* path. Take step: "+aStarPath[0][0]+','+aStarPath[0][1]);
 drawAStarPath(aStarPath);
 console.log("calculated A* path. Take step: "+aStarPath[0][0]+','+aStarPath[0][1]);
 x=aStarPath.at(-1)[0];
 y=aStarPath.at(-1)[1];
 
 if ( ! occupied(x,y) ){  	// if no obstacle then move, else just miss a turn
 console.log("calculated A* path. No obsitcales.");
  ei = x;
  ej = y;
 }
}


function moveLogicalAgent( a )			// this is called by the infrastructure that gets action a from the Mind 
{ 
 var i = ai;
 var j = aj;		 

      if ( a == ACTION_LEFT ) 	i--;
 else if ( a == ACTION_RIGHT ) 	i++;
 else if ( a == ACTION_UP ) 		j++;
 else if ( a == ACTION_DOWN ) 	j--;

 if ( ! occupied(i,j) ) 
 {
  ai = i;
  aj = j;
 }
}




// --- key handling --------------------------------------------------------------------------------------
// This is hard to see while the Mind is also moving the agent:
// AB.mind.getAction() and AB.world.takeAction() are constantly running in a loop at the same time 
// have to turn off Mind actions to really see user key control 

// we will handle these keys: 

var OURKEYS = [ 37, 38, 39, 40 ];

function ourKeys ( event ) { return ( OURKEYS.includes ( event.keyCode ) ); }
	

function keyHandler ( event )		
{
	if ( ! AB.runReady ) return true; 		// not ready yet 

   // if not one of our special keys, send it to default key handling:
	
	if ( ! ourKeys ( event ) ) return true;
	
	// else handle key and prevent default handling:
	
	if ( event.keyCode == 37 )   moveLogicalAgent ( ACTION_LEFT 	);   
    if ( event.keyCode == 38 )   moveLogicalAgent ( ACTION_DOWN  	); 	 
    if ( event.keyCode == 39 )   moveLogicalAgent ( ACTION_RIGHT 	); 	 
    if ( event.keyCode == 40 )   moveLogicalAgent ( ACTION_UP		);   
	
	// when the World is embedded in an iframe in a page, we want arrow key events handled by World and not passed up to parent 

	event.stopPropagation(); event.preventDefault(); return false;
}





// --- score: -----------------------------------


function badstep()			// is the enemy within one square of the agent
{
 if ( ( Math.abs(ei - ai) < 2 ) && ( Math.abs(ej - aj) < 2 ) ) return true;
 else return false;
}


function agentBlocked()			// agent is blocked on all sides, run over
{
 return ( 	occupied (ai-1,aj) 		&& 
		occupied (ai+1,aj)		&&
		occupied (  ai,aj+1)		&&
		occupied (  ai,aj-1) 	);		
} 


function updateStatusBefore(a)
// this is called before anyone has moved on this step, agent has just proposed an action
// update status to show old state and proposed move 
{
 var x 		= AB.world.getState();
 AB.msg ( " Step: " + AB.step + " &nbsp; x = (" + x.toString() + ") &nbsp; a = (" + a + ") " ); 
}


function   updateStatusAfter()		// agent and enemy have moved, can calculate score
{
 // new state after both have moved
 
 var y 		= AB.world.getState();
 var score = ( goodsteps / AB.step ) * 100; 

 AB.msg ( " &nbsp; y = (" + y.toString() + ") <br>" +
		" Bad steps: " + badsteps + 
		" &nbsp; Good steps: " + goodsteps + 
		" &nbsp; Score: " + score.toFixed(2) + "% ", 2 ); 
}





AB.world.newRun = function() 
{
	AB.loadingScreen();

	AB.runReady = false;  

	badsteps = 0;	
	goodsteps = 0;

	
	if ( show3d )
	{
	 BOXHEIGHT = squaresize;
	 ABWorld.init3d ( startRadiusConst, maxRadiusConst, SKYCOLOR  ); 	
	}	     
	else
	{
	 BOXHEIGHT = 1;
	 ABWorld.init2d ( startRadiusConst, maxRadiusConst, SKYCOLOR  ); 		     
	}
	
	
	loadResources();		// aynch file loads		
							// calls initScene() when it returns 

	document.onkeydown = keyHandler;	
		 
};



AB.world.getState = function()
{
 var x = [ ai, aj, ei, ej ];
  return ( x );  
};



AB.world.takeAction = function ( a )
{
  updateStatusBefore(a);			// show status line before moves 

  moveLogicalAgent(a);

  if ( ( AB.step % 2 ) == 0 )		// slow the enemy down to every nth step
    moveLogicalEnemy();


  if ( badstep() )  badsteps++;
  else   			goodsteps++;

   drawAgent();
   drawEnemy();
   updateStatusAfter();			// show status line after moves  


  if ( agentBlocked() )			// if agent blocked in, run over 
  {
	AB.abortRun = true;
	goodsteps = 0;			// you score zero as far as database is concerned 			 
	musicPause();
	soundAlarm();
  }

};



AB.world.endRun = function()
{
  musicPause(); 
  if ( AB.abortRun ) AB.msg ( " <br> <font color=red> <B> Agent trapped. Final score zero. </B> </font>   ", 3  );
  else    				AB.msg ( " <br> <font color=green> <B> Run over. </B> </font>   ", 3  );
};

 
AB.world.getScore = function()
{
    // only called at end - do not use AB.step because it may have just incremented past AB.maxSteps
    
    var s = ( goodsteps / AB.maxSteps ) * 100;   // float like 93.4372778 
    var x = Math.round (s * 100);                // 9344
    return ( x / 100 );                          // 93.44
};


 




// --- music and sound effects ----------------------------------------

var backmusic = AB.backgroundMusic ( MUSIC_BACK );

function musicPlay()   { backmusic.play();  }
function musicPause()  { backmusic.pause(); }

											 
function soundAlarm()
{
	var alarm = new Audio ( SOUND_ALARM );
	alarm.play();							// play once, no loop 
}


// --- altered by Deborah Djon ------------------------------------------------------------

let aStarPath = [];
let aStarPathTiles = [];
let openList = [];
let openListTiles = [];
let closedList = [];
let closedListTiles = [];

let deadEnd = [];
let currentNode = null;


class treeNode {
    constructor(position, goalHeuristic, parentNode){
        this.position = position;
        // heuristic distance to Goal
        this.goalHeuristic = goalHeuristic; //h 
        this.parentNode=parentNode;
        if(parentNode==null){
            this.pathLength = 0; //g
        }else{
            this.pathLength = parentNode.pathLength+1;
        }
        this.cost=this.goalHeuristic+this.pathLength; //f
    }
}

// euclidian distance
function heuristicDistance([x,y]){
    return Math.sqrt((ai-x)*(ai-x)+(aj-y)*(aj-y));
}


function resetStarPath() {
	// remove tiles and path
	aStarPath = [];
    openList = [];
    closedList = [];
    	
	visited = [];
	aStarPathTiles.forEach(tile=>{
	    ABWorld.scene.remove(tile)
	})
	
	openListTiles.forEach(tile=>{
	    ABWorld.scene.remove(tile)
	})
	
	closedListTiles.forEach(tile=>{
	    ABWorld.scene.remove(tile)
	})
	
	aStarPathTiles = [];
	openListTiles = [];
    closedListTiles = [];

}

// function coded from scratch without reference for the maximum learning challange haha
function calculateAStarPath(){
    resetStarPath();
    // open list: nodes I am evaluating 
    // closed list: nodes I have already evaluated
    
    const goalHeuristic = heuristicDistance([ei, ej]);
    const enemyPosition = [ei, ej];
    const agentPosition = [ai, aj];
    const pathLength = 0;
    const parentNode = null;
    
    let agentFound = false;
    let treeRoot = new treeNode(enemyPosition, goalHeuristic, parentNode);
    openList.push(treeRoot);

    // prevent loop from going forever
    loopCount = 0; 
    maxLoopCount = 1000;
    while (!agentFound){
        /*
        sort the open list by f value and then h value
        source sorting: https://levelup.gitconnected.com/sort-array-of-objects-by-two-properties-in-javascript-69234fa6f474
        */
        openList.sort((a, b)=> {
          if (a.cost === b.cost){
            return a.goalHeuristic < b.goalHeuristic ? -1 : 1
          } else {
            return a.cost < b.cost ? -1 : 1
          }
        });
        currentNode = openList.splice(0,1)[0];
        closedList.push(currentNode); //current node
        ; 

        if(currentNode.position.toString() === agentPosition.toString()){
            console.log("agent found");
            agentFound = true;
            break
        }
    	const nextPositions = getNextSteps(currentNode.position);
	    nextPositions.forEach(position=>{
    	    nodesAtPosition = openList.filter(node => node.position.toString()===position.toString());
    	    if (nodesAtPosition.length==0){
    	        //no node with this position is in the open list
    	        newNode = new treeNode(position, heuristicDistance(position), currentNode);
    	        openList.push(newNode)
    	        console.log("added new node to open list. Node at position: "+newNode.position);
    	    }else{
    	        //node is in the open list
    	        //if the node leads to a new shorter path, update the node
    	        nodeAtPositoin = nodesAtPosition[0]
    	        if(nodeAtPositoin.pathLength<currentNode.pathLength){
    	            nodeAtPositoin.parentNode = currentNode;
    	            nodeAtPositoin.pathLength = nodeAtPositoin.parentNode.pathLength+1;
    	            nodeAtPositoin.cost = nodeAtPositoin.goalHeuristic+nodeAtPositoin.pathLength;
    	        }
    	    }
        });

        loopCount++;
        if(loopCount==maxLoopCount){
            agentFound=true;
        }
    }
    
    // Recreate the A* Path
    loopCount = 0;
    while(currentNode.position.toString()!=enemyPosition.toString()){
        aStarPath.push(currentNode.position);
        currentNode = currentNode.parentNode;
        loopCount++;
        if(loopCount==maxLoopCount){
            break
        }
    }
}


function getNextSteps ([x,y]){
            console.log([x,y])
            console.log(currentNode);

    let result = [];
    let positions = [
	                [x+1,y], 
	                [x-1,y], 
	                [x,y+1], 
	                [x,y-1]
	                ];
    positions.forEach(pos => {
        if ((0 < pos[0] < gridsize) && // position within grid
            (0 < pos[1] < gridsize) && 
            (
                (pos.toString() == [ai, aj].toString()) || // the next step is the agent
                (! occupied (pos[0], pos[1])) // no wall or enemy there
            ) &&
            (!closedList.some(node => node.position.toString()==pos.toString())) && //not in closed
            (pos.toString() != currentNode.position.toString())) // I did not come from there
            {
            result.push(pos);
        }
    });
    return result;
}


function drawAStarPath(){
    console.log("draw A* path: "+aStarPath);
    // takes in an array of positions and places squarrs on these positions
    
    color = new THREE.Color("white");
    // draw A* path
    aStarPath.forEach(pos => {
        shape    = new THREE.BoxGeometry ( squaresize, 1, squaresize );			 
        material = new THREE.MeshBasicMaterial( { color: color } );
        material.transparent = true; 
        material.opacity = 0.7;
        tile  = new THREE.Mesh( shape , material);
        position = translate(pos[0],pos[1]);
        position.y = position.y - BOXHEIGHT/2; //for the path
        tile.position.copy(position);
        ABWorld.scene.add(tile);
        aStarPathTiles.push(tile);
    });
    
    // draw closed tiles
    closedList.forEach(node => {
        shape    = new THREE.BoxGeometry ( squaresize, 1, squaresize );			 
        material = new THREE.MeshBasicMaterial( { color: color } );
        material.transparent = true; 
        material.opacity = 0.5;
        tile  = new THREE.Mesh( shape , material);
        position = translate(node.position[0],node.position[1]);
        position.y = position.y - BOXHEIGHT/2; //for the path
        tile.position.copy(position);
        ABWorld.scene.add(tile);
        aStarPathTiles.push(tile);
    });
    
    
    // draw open tiles
    openList.forEach(node => {
        shape    = new THREE.BoxGeometry ( squaresize, 1, squaresize );			 
        material = new THREE.MeshBasicMaterial( { color: color } );
        material.transparent = true; 
        material.opacity = 0.2;
        tile  = new THREE.Mesh( shape , material);
        position = translate(node.position[0],node.position[1]);
        position.y = position.y - BOXHEIGHT/2; //for the path
        tile.position.copy(position);
        ABWorld.scene.add(tile);
        aStarPathTiles.push(tile);
    });
    
}