Code viewer for World: Complex World (clone by An...

// Cloned by Ankit on 13 Nov 2021 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/robocop/Coronavirus.PNG' ;
 const TEXTURE_ENEMY 	= '/uploads/robocop/Vaccine.PNG' ;

 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	   

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  



// ---- Practical 1 - World 1 A* variable declaration ----------

//const diagonal = false; 

//Location
var w1_start_location;
var w1_end_location;

//path variables
var w1_path = []; 

//Sets
var openSet = [];  // list of spots evaluated, starts with initial location
var closedSet = []; // list of spots to be evaluated, starts empty

//Grid variables
var cols = gridsize - 2; // Grid size includes edges 
var rows = cols;
var grid = new Array(cols);

const diagonal = false;

//Best path variables
var nextStepj;
var nextStepi;
var winnerIndexj;
var winnerIndexi;








//--- 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;
 
 
 
 

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;


	
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;

//console.log("values" +i);
//console.log("values" +j);
//console.log("values" +GRID_WALL);

 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
	 
	 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 
	// 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)
}




// A* Util - Utilities to support functionality

//Custom function to remove an object from array
//Loop backwards as you don't want to skip any elements. Looping forward will remove say index 0, this causes all other items to shift and update there index 
function removeFromArray(arr, elt) {
  for (var i = arr.length - 1; i >= 0; i--) {
		if (arr[i] == elt){
			arr.splice(i, 1); // removes the element from the array
		}
  }  
}

function heuristic(a,b) {
	var dist;
	
	if (diagonal) {
		dist = dist(a.i,a.j,b.i,b.j); //calculates displacement
	} else {
		dist = Math.abs(a.i - b.i) + Math.abs(a.j - b.j); //calculates distance without moving diagonally; taxi-cab/manhattan
	}
	
	return dist;
}

// A* step 1 - Setting up the Grid (2d array)

// This functions creates a 2d array to represent the grid 
function setGrid()
{
	console.log('Setting up grid...');
 
	currentSquare = 1;
	
	console.log('Agent Start Location [row_j, col_i] [' + aj + ' ,' + ai + ']');
	console.log('Enemy End Location [row_j, col_i] [' + ej + ' ,' + ei + ']');
	
	// Setup 2D array
	for (var i = 0; i < cols; i++) 
		grid[i] = new Array(rows);
	
	// Creating an object for every spot to store heuristic details 
	for (var i = 0; i < cols; i++) {
		for (var j = 0; j < rows; j++) {
			grid[i][j] = new Spot(i, j);
		}	
	}
	
	// Add neighbors of the spot
	for (var i = 0; i < cols; i++) {
		for (var j = 0; j < rows; j++) {
			grid[i][j].addNeighbors(grid);
		}	
	}	
	
	//Assign start and end location
	w1_start_location = grid[ei-1][ej-1]; // start location asigned
	w1_end_location = grid[ai-1][aj-1]; // end location asigned
	
	console.log("w1_start_location: "+grid[ei-1][ej-1]);
	console.log("w1_end_location: "+grid[ei-1][ej-1]);
	
	//Create openSet for all unvisited neighbors
	openSet.push(w1_start_location);
	
	console.log("openSet: "+grid[ei-1][ej-1]);
	console.log(grid);
}

// A* step 2 - Defining an object for every position to hold 

// This functions creates a spot object to store location coordinates and heuristic details f,g,h by travesring columns and then rows

function Spot(i,j)
{
	console.log("Inside Spot")
	// Location
	this.i = i;
	this.j = j;

	// f, g, and h values for A*
	this.f = 0;
	this.g = 0;
	this.h = 0;
	
	//Keep track of neighbors
	this.neighbors = [];
	this.previous = undefined;
	
	this.addNeighbors = function(grid){
		var i = this.i;
		var j = this.j;
		
		// Neighbors are identified based on position, below handles UP, DOWN, RIGHT & LEFT spots
		
		if (i < cols-1){
			this.neighbors.push(grid[i+1][j]);
		}
		
		if (i > 0){
			this.neighbors.push(grid[i-1][j]);
		}
		
		if (j < rows-1){
			this.neighbors.push(grid[i][j+1]);
		}
		
		if (j > 0){
			this.neighbors.push(grid[i][j-1]);
		}
		
		if (diagonal) {
			if (i > 0 && j > 0){
				this.neighbors.push(grid[i - 1][j - 1]);
			}				
			if (i < cols - 1 && j > 0) {
				this.neighbors.push(grid[i + 1][j - 1]);
			}				
			if (i > 0 && j < rows - 1) {
				this.neighbors.push(grid[i - 1][j + 1]);
			}				
			if (i < cols - 1 && j < rows - 1){
				this.neighbors.push(grid[i + 1][j + 1]);
			}	
		}			
		
	}
	
	
	//Shows the grid
//	this.show() = function(colour) {
//		fill(255);
//		noStroke(0);
//		rect(this.i*(gridsize/squaresize),this.j*(gridsize/squaresize),gridsize/squaresize,gridsize/squaresize)
//	}
}

// A* step 3 - Calculating the best path

// This functions calculates the best path by 

function bestPath()
{
	console.log("Inside Bestpath")
	if (openSet.length > 0) {
		
		var winnerIndex = 0;
		// Check all neighbours and see if the current spot has a f(n) lower than every neighbour
		for (var i = 0; i < openSet.length; i++){
			if (openSet[i].f < openSet[winnerIndex].f) {
				winnerIndex = i;
			}
		}
		
		var current = openSet[winnerIndex];
		
		// If current position is end/agent 
		if (current === w1_end_location){
		    console.log("Reached");
			
			winnerIndexj = null;
			winnerIndexi = null;
			
			console.log('Next step: ' + nextStepj + ' ,' + nextStepi);
			
			winnerIndexj = nextStepj;
			winnerIndexi = nextStepi;
			
			console.log('Winner: ' + winnerIndexj + ' ,' + winnerIndexi);
			
		}else{
        
		}

		
		console.log("Reached here");
		
		removeFromArray(openSet,current);
		//openSet.remove(current); --> No such function to remove value from array
		closedSet.push(current);
		
		var neighbors = current.neighbors;
		//check all possible neighbors 
		for (i = 0; i < neighbors.length; i++){
			var neighbor = neighbors[i];
			
			console.log("Reached inside loop");
			
			//if neighbor not in closedSet
			if (!closedSet.includes(neighbor) ){ //&& !occupied(neighbor)
				var tempG = current.g + 1;
				var newPath = false;
				
				//check if this neighbor has been evaluated before and if now it has a better g value
				if (openSet.includes(neighbor)) {
					if(tempG < neighbor.g){
						neighbor.g = tempG; //distance from start if found a shorter distance
						newpath = true;
					}
				} else {
					neighbor.g = tempG; //distance from start
					newpath = true;
					openSet.push(neighbor);
				}
			if(newPath){
				neighbor.h = heuristic(neighbor,end); //estimated distance to agent
				neighbor.f = neighbor.g + neighbor.h;
				neighbor.previous = current;
			}
			
			}
		}
		
	} else {
		// no solution
		console.log("No Solution");
	}

	//find the path
	var tempPath = current;
	w1_path.push(tempPath);
	//recursively add the previous path untill there is no previous
	while (tempPath.previous) {
		w1_path.push(tempPath.previous);
		tempPath = tempPath.previous;
	}

	//console.log("Reached End, Enemy closest to agent");
	
	//Traveresing the path in reverse 
	
	for (var i =  w1_path.length-1; i >= 0; i--) {
		
		console.log("inside path loop");
     
     var pathj = w1_path[i].j+1;
     var pathi = w1_path[i].i+1;

     var firstIndex = w1_path.length - 1;
     var nextPathIndex;

     if (firstIndex > 0) {
        // console.log('firstIndex > 0');
        nextPathIndex = w1_path.length - 2;
        nextStepj = w1_path[nextPathIndex].j+1;
        nextStepi = w1_path[nextPathIndex].i+1;
     }
     
   }
	
	

	// Debug, drawing	
//	for (var i = 0; i < cols; i++) 
//		for (var j = 0; j < rows; j++)
//			grid[i][j].show(color(255));
//		
//		
//	for (var i = 0; i < closedSet.length; i++) // RED
//		closedSet[i].show(color(255,0,0));
//	
//	for (var i = 0; i < openSet.length; i++)  // GREEN
//		openSet[i].show(color(0,255,0));
//	
//	for (var i = 0; i < path.length; i++)  //BLUE
//		path[i].show(color(0,0,255));


}

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

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

	console.log('Inside moveLogicalEnemy()...'); 
	console.log('Agent Location [' + aj +  ', ' + ai + ']'); 
	console.log('Enemy Location [' + ej +  ', ' + ei + ']'); 
	
	setGrid();

	bestPath();

    var i, j;
     

 
     if ((typeof winnerIndexj !== 'undefined') && (typeof winnerIndexi !== 'undefined')) {
        j = winnerIndexj;
        i = winnerIndexi;     
     }
     else {
        j = nextStepj;
        i = nextStepj;
     }
	
	console.log('Coordinates  [' + i +  ', ' + j + ']'); 
	
	
	if ( !occupied(i,j) ){ // if no obstacle then move
		console.log('Inside occupied()...'); 
		ei = i;
		ej = j;
		console.log('Enemys new location  [' + ej +  ', ' + ei + ']');
	} else {
    		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) )  
		 {
		  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) ) 
 {
  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 

	//if ( ( AB.step % 20 ) == 0 )
		moveLogicalAgent(a);

  //if ( ( AB.step % 20 ) == 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 
}