Code viewer for World: Complex World with Star Wa...

// Cloned by Fergus on 23 Nov 2020 from World "Complex World" by Starter user 
// Please leave this clone trail here.
 

//Fergus Downey
//Student # 20215921

// ==== 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?


 

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

AB.screenshotStep  = 50;    
  
 //100
AB.clockTick       = 10;     // 10 
//1000	
AB.maxSteps        = 1000;     
  
  
  
	// Take screenshot on this step. (All resources should have finished loading.) Default 50.


 //--------seed random generation to allow for comparison of options fdowney-------------
 
var seed=1;
const random_seed=false;
console.log('random seed? = ' + random_seed + '\nrandom seed # = ' + seed);
 
const diagonal = true;
console.log('diagonal enable? = ' + diagonal);

const agent_correction = true ;

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

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

 //Credit = https://pnghut.com/search/moon-monochrome-sphere
 const TEXTURE_WALL 	= 'uploads/fergus24/moon-atmosphere-planet-natural-satellite-blue.jpg'  ;
 //const TEXTURE_MAZE 	= '/uploads/starter/latin.jpg' ;
 
 //const TEXTURE_MAZE 	= 'uploads/fergus24/moon-atmosphere-planet-natural-satellite-blue.jpg' ;
 //const TEXTURE_MAZE 	= 'uploads/fergus24/mars_reduced.png' ;
 //Credit = https://www.vhv.rs/viewpic/hwhoo_mars-planet-png-transparent-png/
  //Credit =https://www.cleanpng.com/png-planet-nine-atmosphere-photography-violet-1921841/
 const TEXTURE_MAZE 	= 'uploads/fergus24/planet-nine-atmosphere.png' ;
 
 //const TEXTURE_AGENT 	= '/uploads/starter/pacman.jpg' ;
 //https://toppng.com/free-image/the-death-star-star-wars-death-star-PNG-free-PNG-Images_171980
 const TEXTURE_AGENT 	= 'uploads/fergus24/the-death-star-star-wars.png' ;
 
 //const TEXTURE_ENEMY 	= '/uploads/starter/ghost.3.png' ;
 //https://www.pngwing.com/en/free-png-nxjlj
 const TEXTURE_ENEMY 	= '/uploads/fergus24/fighter_reduced.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

 
const MUSIC_BACK  = '/uploads/starter/Defense.Line.mp3' ;
const SOUND_ALARM = '/uploads/starter/air.horn.mp3' ;    

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

	
	
const gridsize = 50;						// number of squares along side of world
var cols = gridsize;
var rows = gridsize;
 

const NOBOXES =  Math.trunc ( (gridsize * gridsize ) / 3 );
//Math.trunc ( (gridsize * gridsize) / 10 );
		// density of maze - number of internal boxes
		// (bug) use trunc or can get a non-integer 

const squaresize = 100;					// size of square in pixels
var w = squaresize;
var h = squaresize;

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

 /*const SKYBOX_ARRAY = [										 
                "/uploads/starter/dawnmountain-xpos.png",
                "/uploads/starter/dawnmountain-xneg.png",
                "/uploads/starter/dawnmountain-ypos.png",
                "/uploads/starter/dawnmountain-yneg.png",
                "/uploads/starter/dawnmountain-zpos.png",
                "/uploads/starter/dawnmountain-zneg.png"
                ];
*/

// space_2 skybox, 
// Credit = https://codeworkshop.dev/blog/2020-06-14-creating-a-skybox-with-reflections-in-react-three-fiber/

const SKYBOX_ARRAY = [										 
                "/uploads/fergus24/1.jpg",
                "/uploads/fergus24/2.jpg",
                "/uploads/fergus24/3.jpg",
                "/uploads/fergus24/4.jpg",
                "/uploads/fergus24/5.jpg",
                "/uploads/fergus24/6.jpg",
                ];              
               
                

// space skybox, credit:
// http://en.spaceengine.org/forum/21-514-1
// x,y,z labelled differently

/*
 const SKYBOX_ARRAY = [										 
                "/uploads/starter/sky_pos_z.jpg",
                "/uploads/starter/sky_neg_z.jpg",
                "/uploads/starter/sky_pos_y.jpg",
                "/uploads/starter/sky_neg_y.jpg",
                "/uploads/starter/sky_pos_x.jpg",
                "/uploads/starter/sky_neg_x.jpg"
                ];
				
*/

// urban photographic skyboxes, credit:
// http://opengameart.org/content/urban-skyboxes

/*
 const SKYBOX_ARRAY = [										 
                "/uploads/starter/posx.jpg",
                "/uploads/starter/negx.jpg",
                "/uploads/starter/posy.jpg",
                "/uploads/starter/negy.jpg",
                "/uploads/starter/posz.jpg",
                "/uploads/starter/negz.jpg"
                ];

*/


// ===================================================================================================================
// === 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   

var theagent, theenemy, bestneighbor;
var thepath = [];
  
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;
}


	
function occupied_ae ( 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;
}

function occupied_wm ( i, j )		// is this square occupied
{

 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;
}


     

//added function incase the seedrandom did not work with AB.randomIntAtoB - FD    
function RandomIntAtoB(min, max) {
  return Math.floor((Math.random() * (Math.floor(max)-Math.floor(min)))+Math.floor(min));
}


	
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
	 
	 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, squaresize );			 
			thecube  = new THREE.Mesh( shape );
			thecube.material = new THREE.MeshBasicMaterial( { map: wall_texture } );
			
			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 
   
    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 ;
		
		//shape    = new THREE.SphereGeometry ( squaresize/10, BOXHEIGHT, squaresize ); //This ran into memory issues. fd
		shape    = new THREE.BoxGeometry ( squaresize, BOXHEIGHT, squaresize );	
		thecube  = new THREE.Mesh( shape );
		thecube.material = new THREE.MeshBasicMaterial( { map: maze_texture } );		  

		thecube.position.copy ( translate(i,j) ); 		  	// translate my (i,j) grid coordinates to three.js (x,y,z) coordinates 
		ABWorld.scene.add(thecube);		
	}
	 	 
   
	// 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/2, BOXHEIGHT, squaresize );
	 theenemy = new THREE.Mesh( shape );
 	 theenemy.material =  new THREE.MeshBasicMaterial( { map: enemy_texture, color: 0x11ff00}  ); //added color to make it easier to see. FD
	 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/2, BOXHEIGHT, squaresize );
	 theagent = new THREE.Mesh( shape );
	 theagent.material =  new THREE.MeshBasicMaterial( { map: agent_texture, color: 0xFF005C } ); //added color to make it easier to see. FD
	 //0xf1f2c2
	 ABWorld.scene.add(theagent);
	 drawAgent(); 

	 
	 
  // 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)
}

function drawPath(path_array)		// given ei, ej, draw it 
//function drawPath()
{

}




// A* Heuristic ------Fergus Downey --------------------------------------------------------------------------------------------
// Copied and Edit from "A Star" world - https://ancientbrain.com/world.php?world=2230793148


// Open and closed set
var openSet = [];
var closedSet = [];

// Start and end
var start;
var end;

//counter if enemy gets stuck
var stuck_counter;

// Width and height of each cell of grid
//var w, h;

// The road taken
var path = [];
var agrid = new Array(cols);
var agent_pos_track = [];
//var bad_path = new Array(cols); 




function heuristic(a, e) 
{
    if ( diagonal ) return (AB.distance2D(a.i, a.j, e.i, e.j));
    
    else  return ( Math.abs(a.i - e.i) + Math.abs(a.j - e.j) );

}



// Function to delete element from the array
function removeFromArray(arr, elt) 
{
  // Could use indexOf here instead to be more efficient
  for (var i = arr.length - 1; i >= 0; i--) 
    if (arr[i] == elt) 
      arr.splice(i, 1);
}


// Daniel Shiffman
// Nature of Code: Intelligence and Learning
// https://github.com/shiffman/NOC-S17-2-Intelligence-Learning

// Part 1: https://youtu.be/aKYlikFAV4k
// Part 2: https://youtu.be/EaZxUCWAjb0
// Part 3: https://youtu.be/jwRT4PCT6RU

// An object to describe a spot in the agrid
function Spot(i, j) 
{

  // Location
  this.i = i;
  this.j = j;

  // f, g, and h values for A*
  this.f = 0;
  this.g = 0;
  this.h = 0;

  // Neighbors
  this.neighbors = [];

  // Where did I come from?
  this.previous = undefined;


  // Figure out who my neighbors are
  this.addNeighbors = function(agrid) 
  {
    var i = this.i;
    var j = this.j;
    
    if (i < cols - 1)   this.neighbors.push(agrid[i + 1][j]);
    if (i > 0)          this.neighbors.push(agrid[i - 1][j]);
    if (j < rows - 1)   this.neighbors.push(agrid[i][j + 1]);
    if (j > 0)          this.neighbors.push(agrid[i][j - 1]);
    
if (diagonal)
// diagonals are also neighbours:
{
    if (i > 0 && j > 0)                 this.neighbors.push(agrid[i - 1][j - 1]);
    if (i < cols - 1 && j > 0)          this.neighbors.push(agrid[i + 1][j - 1]);
    if (i > 0 && j < rows - 1)          this.neighbors.push(agrid[i - 1][j + 1]);
    if (i < cols - 1 && j < rows - 1)   this.neighbors.push(agrid[i + 1][j + 1]);
}
    
  }
  
}




function a_star_setup(e_pos, a_pos) 
{


  // Making a 2D array
  for (var i = 0; i < cols; i++) 
    agrid[i] = new Array(rows);

  for (var i = 0; i < cols; i++) 
   for (var j = 0; j < rows; j++) 
      agrid[i][j] = new Spot(i, j);

  // All the neighbors
  for (var i = 0; i < cols; i++) 
    for (var j = 0; j < rows; j++) 
     agrid[i][j].addNeighbors(agrid);


  // Start and end
  start     = agrid[e_pos.i][e_pos.j];
  end       = agrid[a_pos.i][a_pos.j];
  start.wall    = false;
  end.wall      = false;

  // openSet starts with beginning only
  openSet=[];
  openSet.push(start);
    console.log('start search');
    //console.log('i '+ e_pos.i + ' j '+ e_pos.j);  
  
}



function draw() 
// the search goes on over many timesteps 
// each timestep, check one more square and draw current partial solution 
{
    
  
  var winner = 0; 
  while (winner > -1)
  {
      
  // --- begin still searching -----------------------------
  if (openSet.length > 0) 
  {

    // Best next option
    winner = 0; 
  
    //console.log('openset length =  '+ openSet.length);  
  
    for (var i = 0; i < openSet.length; i++) {
        //console.log('openSet[i].f =  '+ openSet[i].f); 
        //console.log('openSet[winner].f =  '+ openSet[winner].f); 
        
        if (openSet[i].f < openSet[winner].f) 
            winner = i;
    }  
     
    //console.log('openset winner = '+ i);      
    var current = openSet[winner];
   //console.log('i '+ openSet[winner].i + ' j '+ openSet[winner].j);  
    

    // Did I finish?
    if (current === end) 
    {
        console.log("success - found path");
      
      
        path = [];
        var temp = current;
        path.push(temp);
        while (temp.previous) 
        {
            path.push(temp.previous);
            temp = temp.previous;
        }

        for (var i = 0; i < thepath.length; i++){  
    
            ABWorld.scene.remove(thepath[i]);
    
        }  
    
        for (var i = 0; i < path.length; i++){
            //drawPath(openSet[i]);
      
            shape    = new THREE.BoxGeometry ( squaresize/10, BOXHEIGHT, squaresize/10 );			 
	        thepath[i] = new THREE.Mesh( shape );
            thepath[i].material = new THREE.MeshBasicMaterial( { color: 0xffff00 } );
      
            thepath[i].position.copy ( translate((path[i].i),(path[i].j)) ); 		  	// translate my (i,j) grid coordinates to three.js (x,y,z) coordinates 
	        ABWorld.scene.add(thepath[i]);

        }
      
      return path;
      //break;
    }

    // Best option moves from openSet to closedSet
    removeFromArray(openSet, current);
    closedSet.push(current);

    // Check all the neighbors
    var neighbors = current.neighbors;
    
    
    
    //--- start of for loop -----------
    for (var i = 0; i < neighbors.length; i++) //neighbours.length=8 if diagonal 
    {
      var neighbor = neighbors[i];

        var valid_diagonal_move = true;
        //a valid diagonal move is when the enemy does not move between two barriers meeting at the edge. FD
        if ((neighbor.i != current.i) && (neighbor.j != current.j)){
            
            var diagonal_move = true;
            //console.log("diagonal move "); //Debug
            valid_diagonal_move = ( occupied_wm(current.i+(neighbor.i-current.i),current.j) === false ) && ( occupied_wm(current.i,current.j+(neighbor.j-current.j)) === false);
            
            //console.log("valid diagonal move " + valid_diagonal_move); //Debug
            
            
        }


      // Valid next spot?
      if (!closedSet.includes(neighbor) && !occupied_wm(neighbor.i,neighbor.j) && valid_diagonal_move==true)  ////key statement to determin if location is a valid move. FD
      {
        var tempG = current.g + heuristic(neighbor, current);
        //console.log('temp G =  '+ tempG); //Debug
        //console.log('current.g =  '+ current.g);  //Debug
        //console.log('neighbor.g =  '+ neighbor.g);    //Debug       
        // Is this a better path than before?
        var newPath = false;
        if (openSet.includes(neighbor)) 
        {
          if (tempG < neighbor.g) 
          {
            neighbor.g = tempG;
            newPath = true;
          }
        }
        else 
        {
          neighbor.g = tempG;
          newPath = true;
          openSet.push(neighbor);
        }

        // Yes, it's a better path
        if (newPath) 
        {
            //console.log('neighbour loop # ' + i);
          neighbor.h = heuristic(neighbor, end);
          neighbor.f = neighbor.g + neighbor.h;
          neighbor.previous = current;
        }
      }
    }
    //--- end of for loop -----------
    
  }
  // --- end still searching -----------------------------
  
  

  else 
  {
    console.log('fail - no path exists');
    
    path=[]
    path[0] = 0;
    return path;

  }


    
  } // end of while loop 

}

//-----------------------------------------end of additional code FDOWNEY------------------------------------------------------

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

function moveLogicalEnemy()
{ 
// move towards agent 
// put some randomness in so it won't get stuck with barriers 

 var i, j;
 

 enemy_pos = new Array(2);
 agent_pos = new Array(2);
 
 enemy_pos.i = ei;
 enemy_pos.j = ej;
 agent_pos.i = ai;
 agent_pos.j = aj;
 

 f = heuristic(enemy_pos, agent_pos); 
 
 a_star_setup(enemy_pos, agent_pos); // A* Setup FD
 var path = draw(); // A* Run FD
 
 
 console.log('enemy postion '+ ei + ' ' + ej);
 console.log('agent postion '+ ai + ' ' + aj);
 //console.log('path length '+ (path.length));
 //for (var i = 0; i < path.length; i++){
    //console.log('best path route '+ path[i].i + ' ' + path[i].j);
 //}    
  
 
 if ((path.length)>1){
    i = path[(path.length)-2].i;
    j = path[(path.length)-2].j;
 }
 else
 {
    i=ei;
    j=ej;
 }
 
 //this code is to make sure the agent does not get stuck in a loop and keeps moving by forcing the enemy into the next loop position and therefore knocking the agent out of it. FD
 agent_pos_track.push(agent_pos);
 
 
if ((agent_pos_track.length > 6) && (path.length <3) && (agent_correction === true)) { 
     
    
    if ((agent_pos_track[2].i = agent_pos.i) && (agent_pos_track[2].j = agent_pos.j) && (agent_pos_track[4].i = agent_pos.i) && (agent_pos_track[4].j = agent_pos.j) ){
        i=agent_pos_track[agent_pos_track.length-2].i;
        j=agent_pos_track[agent_pos_track.length-2].j;
    }
}
    
 
 
 

 while ( occupied_wm(i,j) )  	// if Wall or Maze obstacle then pick a random alternaitve spot either side to move.
 {
  var sign = AB.randomIntAtoB(-1, +1); 
  
  i = ei+sign; 
  if(sign === 0){
    j = AB.randomIntAtoB(ej-1, ej+1);
  }
  else
  {
    j = AB.randomIntAtoB(0, ej-sign);  
  }
  
 //stuck_counter++;
 }
 if( ! occupied(i,j) )  	// if obstacle is agent then stay still. Update if agent is stuck in repetitive move to agents side.
 {
  ei = i;
  ej = j;
 }
 
 
 

 
 
 
 console.log('new enemy postion '+ ei + ' ' + ej);
 
 
 
 
}


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() 
{

    //Autor = David Bau https://github.com/davidbau/seedrandom/commits?author=davidbau
    //https://github.com/davidbau/seedrandom/blob/released/seedrandom.js
    if (random_seed === true){
        
        $.getScript('/uploads/fergus24/seedrandom.js')
            .done(function() {
                console.log('seedrandom.js loaded properly with seed: ' + seed);
                Math.seedrandom(seed);
                random_draw = Math.random();
                //console.log('random number 1 = ' +   random_draw);
            }).fail(function() {
              console.log('seedrandom.js failed to load');
          });
          
    //Hacked with below code as without it, seedrandom gets loaded after maze is generated. FD      
    $.ajax({
        dataType: '/uploads/fergus24/seedrandom.js',
        async: false
    });  
    }

	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();
  }
  
  if (path[0] === 0)     //if there is no valid path stop run. FD
  {
  	AB.abortRun = true;
	goodsteps = 0;						 
	musicPause();
	soundAlarm();
  }

};



AB.world.endRun = function()
{
  musicPause(); 
  if ( AB.abortRun  ){
      if (path[0] === 0) 
      {
          AB.msg ( " <br> <font color=red> <B> No valid path. </B> </font>   ", 3  ); //if there is no valid path stop run. FD
      }
      else  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 
}