Code viewer for World: Complex World (clone by Toma)

// Cloned by Toma on 25 Oct 2023 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       = 100;    

	// 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' ;

// 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 TEXTURE_WALL 	= '/uploads/toma2601/1699746830.png' ;
 const TEXTURE_MAZE 	= '/uploads/toma2601/1699748370.png' ;
 const TEXTURE_AGENT 	= '/uploads/starter/pacman.jpg' ;
 const TEXTURE_ENEMY 	= '/uploads/toma2601/goldenjackalanubisvectorillustrationn.jpg' ;

// credits:
// https://www.freepik.com/free-vector/closed-open-egyptian-treasure-chest-set_41964808.htm#page=4&query=egypt&position=41&from_view=search&track=sph
// https://www.freepik.com/free-vector/egyptian-hieroglyphics-background-with-flat-design_2720580.htm#query=egypt&position=0&from_view=search&track=sph
// https://commons.wikimedia.org/wiki/Category:Skull_and_crossbone_icons
// https://www.freepik.com/free-vector/golden-jackal-anubis-vector-illustration_74221054.htm#page=13&query=egypt&position=0&from_view=search&track=sph


 
	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 = 40; // 20;						// number of squares along side of world	   

// const NOBOXES =  100; 
const NOBOXES = Math.trunc ( (gridsize * gridsize) / 3 );     // 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 

// skybox credit:
// Panoramic image: https://www.freepik.com/free-vector/egyptian-pyramids-nile-river-sunset_39709567.htm#query=egypt&position=19&from_view=search&track=sph
// Converted Panoramic to cubemap: https://jaxry.github.io/panorama-to-cubemap/


 const SKYBOX_ARRAY = [										 
                "/uploads/toma2601/purple_px.png",
                "/uploads/toma2601/purple_nx.png",
                "/uploads/toma2601/purple_py.png",
                "/uploads/toma2601/purple_ny.png",
                "/uploads/toma2601/purple_pz.png",
                "/uploads/toma2601/purple_nz.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;
 
 
 
 

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;


//--- A* star global variables---------

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

// Start and end
var start;
var end;

// The road taken
var path = [];
var stepVector = [];

// recording number of searched states
var searchedStepStates =0;
var searchedTotalStates = 0;


//----A star functions ---------
// Credits: 
// Ancient Brain's A star program by "Coding Train" project - https://ancientbrain.com/world.php?world=2230793148
// https://www.geeksforgeeks.org/a-search-algorithm/


function heuristic ( a, b ) 
{
    // Manhattan Distance
    return Math.abs(a.i - b.i) + Math.abs(a.j - b.j);
    // return 0;
}


function gfn(a, b) {
  return Math.abs(a.i - b.i) + Math.abs(a.j - b.j); 
}

function removeFromArray(arr, elt) {
  for (var i = arr.length - 1; i >= 0; i--) 
    if (arr[i] == elt) 
        arr.splice(i, 1);
}

//Define grid object
function Spot(i, j, type = GRID_BLANK) {
  // 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 = [];
  this.wall = false;
  this.maze = false;
  // Where did I come from?
  this.previous = undefined;
  if (type == GRID_WALL) this.wall = true;
  if (type == GRID_MAZE) this.maze = true;
  // 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]);
 
  };
}

function aStar() {
    start = GRID[ei][ej]; // Enemy Position
    end = GRID[ai][aj];   // Agent Position
    
    closedSet = [];
    openSet = [];
    
    
    var current = null;
    
    searchedStepStates= 0;
    
    
    openSet.push(start);
    
    var stopSearch = false;
    
    
    while ( !stopSearch ) {
        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) winner = i;
                current = openSet[winner];
          searchedStepStates++;
          // Did I finish?
          if (current === end) {
            stopSearch = true;
            break;
          }
          // Best option moves from openSet to closedSet
          removeFromArray(openSet, current);
          closedSet.push(current);
          
    
          // Check all the neighbors
          var neighbors = current.neighbors;
    
          for (i = 0; i < neighbors.length; i++) {
            var neighbor = neighbors[i];
            
            
            // Valid next spot?
            if (!closedSet.includes(neighbor) && !neighbor.wall && !neighbor.maze) {
              var g = current.g + gfn(neighbor, current); // add up g values in cumulative way
    
              // Is this a better path than before?
              var newPath = false;
              if (openSet.includes(neighbor)) {
                if (g < neighbor.g) {
                  neighbor.g = g;
                  newPath = true;
                }
              } else {
                neighbor.g = g;
                newPath = true;
                openSet.push(neighbor);
              }
    
              // Yes, it's a better path
              if (newPath) {
                neighbor.h = heuristic(neighbor, end);
                neighbor.f = neighbor.g + neighbor.h;
                neighbor.previous = current;
              }
            }
          }
          
        } else {
            // No route found
            stopSearch = true;
            break;
        }
    }
    
    
    // Handling Path
    var nPath = buildPath(current);
    var newPosition = { i: start.i, j: start.j };
    
    // if path contains nodes apart from the start and end, move
    if( nPath.length > 2 ) {
        newPosition.i = nPath[nPath.length-2].i ;
        newPosition.j = nPath[nPath.length-2].j ;
            console.log("New Path:", newPath,newPosition ) 
    }
    
    // Reset all grids to original state
    resetGrids();
    console.log("Number of states searched in this Step: " + searchedStepStates);
    searchedTotalStates += searchedStepStates;
    return newPosition;
}

function resetGrids() {
    for (var i = 0; i < gridsize; i++){
        for (var j = 0; j < gridsize; j++) {
            GRID[i][j].previous = undefined;
            GRID[i][j].f=GRID[i][j].h=GRID[i][j].g=0;
        }        
    }
}

function buildPath(end) {
    var newPath = [];
    stepVector = [];
    // Traverse revese to get the path
    var step = end;
    do {
        newPath.push(step);
        stepVector.push(translate(step.i, step.j));
        step = step.previous;   
    }
    while (step.previous)
    stepVector = stepVector.slice(1, stepVector.length - 2);
    path = [...newPath]  // update global path with new path
    return newPath
}

function drawPath() {
    const radius = 15;
    const tubeRadius = 6;
    const radialSegments = 8;
    const tubularSegments = 24;
    var geometry = new THREE.TorusBufferGeometry(radius, tubeRadius, radialSegments, tubularSegments);
    stepVector.forEach((vector,index)=>{
        var shape  = new THREE.Mesh( geometry );
        	shape.material = new THREE.MeshBasicMaterial({ 
        	    color: 0xff5733, 
        	    opacity: 0.2+ (1-index/stepVector.length),
                transparent: true,
        	});
			shape.position.copy ( vector );
			shape.rotation.x = 0.5 * -Math.PI;
			shape.scale = new THREE.Vector3( 2, 2, 0 );
			shape.name  = "ASTARPATH"
			ABWorld.scene.add(shape);
    });
    
    const material = new THREE.LineDashedMaterial( { color: 0xff5733, dashSize: 1, gapSize: 0.5, scale: 2 } );
    geometry = new THREE.BufferGeometry().setFromPoints( stepVector );
    const line = new THREE.Line( geometry, material );
    line.computeLineDistances()
    line.name = "ASTARPATHLINE"
    ABWorld.scene.add( line );
}

function removePath() {
    for(var i=0; i<stepVector.length+3; i++){
        ABWorld.scene.remove(ABWorld.scene.getObjectByName("ASTARPATH")); 
    }
    ABWorld.scene.remove(ABWorld.scene.getObjectByName("ASTARPATHLINE")); 
}

// --------- End of A* Variables and functions ---------------------

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].wall ) return true;		// fixed objects	 
 if ( GRID[i][j].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
	 
	 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] = new Spot(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] = new Spot(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] = new Spot(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 neighbours - A star
	for (i = 0; i < gridsize; i++)
        for (j = 0; j < gridsize; j++) 
            GRID[i][j].addNeighbors(GRID); 
   
	// 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 );			 
	 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 );			 
	 theagent = new THREE.Mesh( shape );
	 theagent.material =  new THREE.MeshBasicMaterial( { map: agent_texture } );
	 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)
}




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




function moveLogicalEnemy()
{ 
    console.log("Move Logical Enemy")
    var newPos = aStar();
    console.log("New Position", newPos );
    
    if (newPos === GRID[ai][aj]){
        console.log("Agent trapped")
        AB.world.endRun;
        musicPause();
    }
    else{
    ei = newPos.i;
    ej = newPos.j;
    drawPath(); 
    }
}


function moveLogicalAgent( a )			// this is called by the infrastructure that gets action a from the Mind 
{ 
    
     console.log("Move Logical Agent")
 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;
    searchedStatesCount = 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 )
{
  //remove old path 
  removePath();
  
  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  );
  console.log("Number of Total states searched: " + searchedTotalStates);
  console.log("Average Searched states for each step: " + searchedTotalStates/(goodsteps+badsteps));
};

 
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 
}