Code viewer for World: Complex World clone: The A...

// Cloned by K.Ellis on 27 Oct 2019 from World "Complex World" by Starter user 
// Please leave this clone trail here.
 



// ==== Starter World ===============================================================================================
// (c) Ancient Brain Ltd. All rights reserved.
// This code is only for use on the Ancient Brain site.
// This code may be freely copied and edited by anyone on the Ancient Brain site.
// This code may not be copied, re-published or used on any other website.
// To include a run of this code on another website, see the "Embed code" links provided on the Ancient Brain site.
// ==================================================================================================================



// =============================================================================================
// 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       = 100;    

	// Speed of run: Step every n milliseconds. Default 100.
	
AB.maxSteps        = 500;    

	// 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) 


 
 //+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 //               KE - added image files
 //+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    //const TEXTURE_MAZE 	= '/uploads/starter/latin.jpg' ; 
    //const TEXTURE_WALL 	= '/uploads/starter/door.jpg' ; 
    const TEXTURE_WALL 	= '/uploads/ke737/ivy-hedging.jpg' ; // KE - source - https://www.hedgesonline.co.uk/evergreen-hedging/ivy-hedging.html
    const TEXTURE_MAZE 	= '/uploads/ke737/grass.jpg' ; //       KE - source - https://www.123rf.com/photo_105664394_seamless-fake-grass-background-on-sunny-day.html
    const TEXTURE_AGENT 	= '/uploads/ke737/danOdonnell.jpg'; //  KE - source - https://www.independent.ie/business/irish/profits-at-singer-daniel-odonnell-firm-fall-slightly-36197484.html
    const TEXTURE_ENEMY 	= '/uploads/ke737/terminator22.jpg'; // KE - source - A screenshot from the trailer for Terminator 2: Judgement Day. (Youtube)

//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

// 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

//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
//               KE - added image files
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 
    //const MUSIC_BACK  = '/uploads/starter/Defense.Line.mp3' ; // https://ancientbrain.com/uploads/ke737/CARBONKILLER-Terminator2theme.mp3
    //const SOUND_ALARM = '/uploads/starter/air.horn.mp3' ;
    
    const MUSIC_BACK  = '/uploads/ke737/CARBONKILLER-Terminator2theme.mp3' ; // KE - source - https://carbonkiller.bandcamp.com/track/terminator-2-theme
    const SOUND_ARNOLD = '/uploads/ke737/t2_hasta_la_vista.wav' ; // Source http://www.wavsource.com/movies/terminator.htm
    const SOUND_BBACK = '/uploads/ke737/t1_be_back.wav' ; // Source http://www.wavsource.com/movies/terminator.htm
    const SOUND_TERM = '/uploads/ke737/t2_terminator.wav' ; // Source http://www.wavsource.com/movies/terminator.htm

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

//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
	
	
const gridsize = 20;						// number of squares along side of world	   

const NOBOXES =  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

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 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;
 

//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
//  KE added const
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    
    const diagonal = true;
    
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++



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;
  
var wall_texture, agent_texture, enemy_texture, maze_texture; 

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

var badsteps;
var goodsteps;



//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// KE added var's
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

    var openSet = []; 
    var closedSet = []; 
    var counter1 = 0;
    var counter2 = 0;

//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

	
	
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;
}


//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
//                KE - START of A* functions
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++


// Our heuristic function
// KE: in order of performance based on 20 runs diagonal true / false
function heuristic(a, b) 
{
    // heuristic 1:  ~80% on diagnoal true / false
    var dist =  ( Math.abs(b.i - a.i)  +  Math.abs(b.j - a.j) );
    
    // heuristic 2: ~75% on diagnoal ~65% on not
    //var a1 = (translate(a.i,a.j));
    //var b1 = (translate(b.i,b.j));
    //var dist = a1.distanceTo(b1);
    
    // heuristic 3 ~60% on diagnoal ture / false
    //var dist = AB.distance2D ( a.i, b.i, a.j, b.j ); 
    
    //console.log('ai = ' + ai + ' , aj = ' + aj); //KE check that ai, aj changes
    
    return dist;
    
 /* 
   KE - could consider probability based metric to aid A* based on observed limited movement of Agent i.e. movements localised
        e.g. simple one might be to skip n Agent movements because there is good probablity Agent will move back to calculated path location
   KE - could implement D* oor GAA but then not A* 
 */

}


// 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);
}


// An object to describe a spot in the grid
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;

  // Am I a wall?
  if(GRID[i][j] == GRID_WALL) //
  {
      this.wall = true; 
      //console.log('wall set to ' + this.wall);
      counter1++;
  }
  else this.wall = false;
  //console.log('wall is false');
  
    // Am I a Maze?
  if(GRID[i][j] == GRID_MAZE) //KE consider NOBOXES or other here, this look slike its doing nothing
  {
      this.maze = true; 
      //console.log('maze set to  ' + this.maze);
      counter2++;
  }
  else this.maze = false;
  //console.log('maze is false');

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



function aStar() 
// the search goes on over many timesteps 
// each timestep, check one more square and note current partial solution 
// KE A* is not ideal for a dynamic target
{
    var i;
    var j;
    
   // --- begin searching -------------------------------------------------------
  if (openSet.length > 0) 
  {   
     

    // Best next option
    var winner = 0;
    
    for (var i = 0; i < openSet.length; i++) 
        if (openSet[i].f < openSet[winner].f) //KE can use h but not A* & can get stuck
           winner = i;
           var current = openSet[winner];
           console.log('\x1b[35m [[ Terminator ]] ' + ' [' + current.i + '] ' + ' [' + current.j + '] ' + ' --- f: ' + current.f + ' g:' + current.g + ' h: ' + current.h);
           
          
    // Did I finish?
    if (current == target) 
    {
       ei = current.i; // ensure terminator/enemy moves to last position if same as target
       ej = current.j;
      
      //KE - and draw the terminator/enemy
       theenemy.material =  new THREE.MeshBasicMaterial( { map: enemy_texture } );
       ABWorld.scene.add(theenemy);
       drawEnemy(ei,ej);		 
       
       AB.abortRun = true;
       console.log("\x1b[31m Daniel has been Terminated");
       AB.msg ( " <font color=red> <B> Daniel has been Terminated </B> </font> <br>" +
       "But his dynamic dancing can win, the A* is an old model", 3  ), soundArnold();
    }

    // Best option moves from openSet to closedSet
    //KE - this can be thought of as like a stack or queue 
    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++) 
    {
      var neighbor = neighbors[i];
      
      // Valid next spot?  Can swap out closedSet if we want to change game win scenario, then not bounded by empty openset
      //if (!occupied(i,j))
      if (!closedSet.includes(neighbor) && !neighbor.wall && !neighbor.maze) //KE added !neighbor.maze 
      {
         
        var tempG = current.g + heuristic(neighbor, current); 

        // 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) 
        {
          neighbor.h = heuristic(neighbor, target); // KE dist to 'target' from n
          neighbor.f = neighbor.g + neighbor.h; //KE our A* algo
      
    //---------------- KE - Move here ------------------------------------------
          
          ei = neighbor.i;
          ej = neighbor.j;
          
          neighbor.previous = current; 
          
          
        }
      }
      
    }
    //--- end of for loop ------------------------------------------------------
    
       
  }
  // --- end still searching ---------------------------------------------------
  else 
  {
    console.log('\x1b[32m Daniel dodged the Terminator this time!!');
    AB.msg ( " <font color=green> <B> Daniel dodged the Terminator this time!! </B> </font> <br>" +
    "His dynamic dancing confuses the A* Terminator <br> " +
    "Hopefully the D* Terminator is not sent back!!  ", 3  ), soundBback();
    AB.abortRun = true;
  }
  
}



//--------------KE - sound effects------------------------------------------------
function soundArnold()
{
	var alarm2 = new Audio ( SOUND_ARNOLD );
	alarm2.play();							// play once, no loop 
}

function soundBback()
{
	var alarm3 = new Audio ( SOUND_BBACK );
	alarm3.play();							// play once, no loop 
}

function soundTerminator()
{
	var alarm3 = new Audio ( SOUND_TERM );
	alarm3.play();							// play once, no loop 
}

//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
//                KE - END of A* functions
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++



//------------ init -------------------------------------------------------------

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.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 
	 do
	 {
	     i = AB.randomIntAtoB(1,gridsize-2);// start in random location
	     j = AB.randomIntAtoB(1,gridsize-2);
	     //i = (1, gridsize - 19);	//KE start in corner
	     //j = (1, gridsize - 19);
	 }
	 while ( occupied(i,j) );  	  // search for empty 

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



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

	 ai = i;
	 aj = j;
	 
	 shape    = new THREE.BoxGeometry ( squaresize, BOXHEIGHT, squaresize );			 
	 theagent = new THREE.Mesh( shape );
	 theagent.material =  new THREE.MeshBasicMaterial( { map: agent_texture } );
	 ABWorld.scene.add(theagent);
	 drawAgent(); 
	 
//----------------------- KE added ---------------------------------------------
	// ** KE ** - create our spots in GRID array
	 for (var i = 0; i < gridsize; i++) 
	    for (var j = 0; j < gridsize; j++) 
	    GRID[i][j] = new Spot(i, j); 
	    
	 // ** KE ** - add all the neighbors
    for (var i = 0; i < gridsize; i++) 
        for (var j = 0; j < gridsize; j++) 
        GRID[i][j].addNeighbors(GRID);
        console.log(GRID);
//------------------------------------------------------------------------------
 
	 // Start and target coordinates
	 start          = GRID[ei][ej];  // 
	 target         = GRID[ai][aj]; //KE variable for target which will change
	 console.log('A* Terminator start = ' + start.i + ', ' + start.j); //KE
	 soundTerminator();
	 console.log("Daniel O'D start = " + target.i + ', ' + target.j); //KE 
	 console.log('num of boundary walls ' + counter1 + ', num of maze walls ' + counter2);
     start.wall     = false;
     start.maze     = false;
     target.wall    = false;
     target.maze    = false;
     
      // openSet starts with beginning only
      openSet.push(start); 
      console.log(start); 
      console.log(openSet); 
      
      
  // 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
	 });
	 
}
 
// -------------- end init -----------------------------------------------------



// --- 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()
{ 
    //---------------------------------------------------------------------------
    //   ** KE ** - we will call the aStar() function instead to use in search & move
    //---------------------------------------------------------------------------
    
    aStar();
    
    
    /*
    // move towards agent 
    // put some randomness in so it won't get stuck with barriers 
    
    
     var i, j;
    
     if ( ei < ai ) i = AB.randomIntAtoB(ei, ei+1); 
     if ( ei == ai ) i = ei; 
     if (ei > ai ) i = AB.randomIntAtoB(ei-1, ei); 
    
     if ( ej < aj ) j = AB.randomIntAtoB(ej, ej+1); 
     if ( ej == aj ) j = ej; 
     if ( ej > aj ) j = AB.randomIntAtoB(ej-1, ej); 
     
     if ( !occupied(i,j))  	// if no obstacle then move, else just miss a turn
     {
         ei = i;
         ej = j; 
     }
     */

}


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))  	// need to change, given A* loop
        if(!GRID[i][j].wall && !GRID[i][j].maze) 
         {
                ai = i;
                aj = j; 
                target = GRID[i][j];
                console.log('Target: ' + target.i + ', ' + target.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;
}

//KE return to this if time, this function will nee dmodifiction , else mod to occupied
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; 
  var score = ( AB.step / 289 ) * 100; 
  var score2 = ( 100 - score ); 

/* AB.msg ( " &nbsp; y = (" + y.toString() + ") <br>" +
		" Bad steps: " + badsteps + 
		" &nbsp; Good steps: " + goodsteps + 
		" &nbsp; Daniel's Score: " + score.toFixed(2) + "% ", 2 ); */
		
		AB.msg ( 
		" &nbsp;A* Terminator Score: " + score2.toFixed(2) + '% ' + 
		" &nbsp;Daniel's Score: " + score.toFixed(2) + "% <br>", 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();
	soundArnold();
  }

};



AB.world.endRun = function()
{
  musicPause(); 
  if ( AB.abortRun ) AB.abortRun = true;
  else  AB.msg ( " <br> <font color=green> <B> Daniel beat the Terminator. </B> </font>   ", 3  ), soundBback(); // if 1000 step
};


 
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 alarm1 = new Audio ( SOUND_ALARM );
	alarm1.play();							// play once, no loop 
}