Code viewer for World: Can the developer fix the ...

// ==== 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 = 9999;

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


const TEXTURE_WALL = '/uploads/developdaniels/code.png';
const TEXTURE_MAZE = '/uploads/developdaniels/error.jpg';
const TEXTURE_AGENT = '/uploads/developdaniels/bug.png';
const TEXTURE_ENEMY = '/uploads/developdaniels/developer.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 = 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/developdaniels/backgroundcode.jpg",
	"/uploads/developdaniels/backgroundcode.jpg",
	"/uploads/developdaniels/backgroundcode.jpg",
	"/uploads/developdaniels/backgroundcode.jpg",
	"/uploads/developdaniels/backgroundcode.jpg",
	"/uploads/developdaniels/backgroundcode.jpg"
];


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

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


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

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

//A* Stuff
var SpotGrid = new Array(gridsize); //Matrix of object  Spot() 
var openSet = [];
var closedSet = [];
var enemy;
var agent;
var path = [];
var diagonal = true;
var autoTrap = true; 			
//My autotrap feature. If it is on, it will use A* to calculate the route from the developer to the bug.
// Turn it off and see a probably game endless. There are two auxiliary functions used: isTraped and trapDoorLocation

var keepAllPathsDone = true;	
//If true draw all the paths calculated. If false, draw just the last path calculated. 
//Best seen when the developer and the bug start distant from each other.

function dist(x1, y1, x2, y2) {
	//Return the Euclidian distance from (x1,y1) to (x2,y2)
	var distX = Math.abs(x1 - x2);
	var distY = Math.abs(y1 - y2);
	return Math.sqrt(distX * distX + distY * distY);
}

function heuristic(a, b) {
	//Given the spots “a” and “b”, returns our heuristic function. In that case, the Euclidian distance
	return (dist(a.i, a.j, b.i, b.j));
}

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);
}

var theagent, theenemy;

var wall_texture, agent_texture, enemy_texture, maze_texture;


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

var badsteps;
var goodsteps;



function loadResources()                // asynchronous file loads - call initScene() when all finished 
{
	var loader1 = new THREE.TextureLoader();
	var loader2 = new THREE.TextureLoader();
	var loader3 = new THREE.TextureLoader();
	var loader4 = new THREE.TextureLoader();

	loader1.load(TEXTURE_WALL, function (thetexture) {
		thetexture.minFilter = THREE.LinearFilter;
		wall_texture = thetexture;
		if (asynchFinished()) initScene();            // if all file loads have returned 
	});

	loader2.load(TEXTURE_AGENT, function (thetexture) {
		thetexture.minFilter = THREE.LinearFilter;
		agent_texture = thetexture;
		if (asynchFinished()) initScene();
	});

	loader3.load(TEXTURE_ENEMY, function (thetexture) {
		thetexture.minFilter = THREE.LinearFilter;
		enemy_texture = thetexture;
		if (asynchFinished()) initScene();
	});

	loader4.load(TEXTURE_MAZE, function (thetexture) {
		thetexture.minFilter = THREE.LinearFilter;
		maze_texture = thetexture;
		if (asynchFinished()) initScene();
	});

}


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




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


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

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

	return false;
}


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

function translate(i, j) {
	var v = new THREE.Vector3();

	v.y = 0;
	v.x = (i * squaresize) - (MAXPOS / 2);
	v.z = (j * squaresize) - (MAXPOS / 2);

	return v;
}


// An object to describe a spot in the grid
function Spot(i, j) {
	//Based on Daniel´s Shiffman code. It has:
	//I,J positions
	//f, g ,h values
	//previous: pointer to previous Spot object in the path

	this.i = i;
	this.j = j;

	this.wall = false;
	this.neighbors = [];

	// f, g, and h values for A*
	this.f = 0;
	this.g = 0;
	this.h = 0;
	// Where did I come from?
	this.previous = undefined;

	// Figure out who my neighbors are
	this.addNeighbors = function () {
		//Based on Daniel´s Shiffman code. It adds the neighbours from each spot 
		var i = this.i;
		var j = this.j;

		if (i < gridsize - 1)
			this.neighbors.push(SpotGrid[i + 1][j]);
		if (i > 0)
			this.neighbors.push(SpotGrid[i - 1][j]);
		if (j < gridsize - 1)
			this.neighbors.push(SpotGrid[i][j + 1]);
		if (j > 0)
			this.neighbors.push(SpotGrid[i][j - 1]);

		if (diagonal) {
			if (i > 0 && j > 0)
				this.neighbors.push(SpotGrid[i - 1][j - 1]);
			if (i < gridsize - 1 && j > 0)
				this.neighbors.push(SpotGrid[i + 1][j - 1]);
			if (i > 0 && j < gridsize - 1)
				this.neighbors.push(SpotGrid[i - 1][j + 1]);
			if (i < gridsize - 1 && j < gridsize - 1)
				this.neighbors.push(SpotGrid[i + 1][j + 1]);
		}
	}
}

function initScene()
{
	var i, j, shape, thecube;

	// set up GRID as 2D array
	SpotGrid = new Array(gridsize);
	for (i = 0; i < gridsize; i++) {
		GRID[i] = new Array(gridsize);
		SpotGrid[i] = new Array(gridsize);
	}

	// set up walls
	for (i = 0; i < gridsize; i++)
		for (j = 0; j < gridsize; j++) {

			SpotGrid[i][j] = new Spot(i, j);

			if ((i == 0) || (i == gridsize - 1) || (j == 0) || (j == gridsize - 1)) {
				GRID[i][j] = GRID_WALL;
				SpotGrid[i][j].wall = true;

				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;
				SpotGrid[i][j].wall = false;
			}
		}
	// 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;
		SpotGrid[i][j].wall = true;

		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);
	}


	// All the neighbors
	for (var i = 0; i < gridsize; i++)
		for (var j = 0; j < gridsize; j++)
			SpotGrid[i][j].addNeighbors();

	console.log('start app');
	console.log(SpotGrid);

	//Enemy always start on the top left corner (To see better the A* path)
		 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();

	//Agent always start on bottom right corner (To see better the A* path)
	 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;
	 
	//Function that initialize A Star for a fresh state
	//Clean openSet, closedSet, SpotGrid.f, SpotGrid.g, SpotGrid.h, SpotGrid.previous
	SetupAStar();

	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
	});

}

function SetupAStar() {
	//Reset the variables used in A Star algorithm 
	//Reset f,g,h,previous of SpotGrid
	//Reset openSet and closedSet

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

	// closedSet starts empty
	closedSet = [];
	// openSet starts with beginning only
	openSet = [];
}

// --- 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 isTraped(i, j) {
	//Parameters are agent position. Returns if the bug is on a trap. He is on a trap if he is between 3 walls. 
	//In the image the bug is the yellow, and the red notes are the spots of interest.
	var numberOfWalls = 0;
	if (SpotGrid[i][j - 1].wall)
		numberOfWalls++;

	if (SpotGrid[i - 1][j].wall)
		numberOfWalls++;

	if (SpotGrid[i + 1][j].wall)
		numberOfWalls++;

	if (SpotGrid[i][j + 1].wall)
		numberOfWalls++;

	if (numberOfWalls == 3)
		return true;
	else
		return false;
}

function trapDoorLocation(i, j) {
	//Given the bug I,J position – returns the trap door. On the above figure, the position when there is no wall. 
	//Must be used when it is trapped, otherwise can return any position.

	if (!SpotGrid[i][j - 1].wall)
		return SpotGrid[i][j - 1];

	if (!SpotGrid[i - 1][j].wall)
		return SpotGrid[i - 1][j];

	if (!SpotGrid[i + 1][j].wall)
		return SpotGrid[i + 1][j];

	if (!SpotGrid[i][j + 1].wall)
		return SpotGrid[i][j + 1];

}

function moveLogicalEnemy() {
	//It is the main function. It is called on every step. 
	enemy = SpotGrid[ei][ej];
	agent = SpotGrid[ai][aj];

	//Function that initialize A Star for a fresh state
	//Clean openSet, closedSet, SpotGrid.f, SpotGrid.g, SpotGrid.h, SpotGrid.previous
	SetupAStar();

	var aStarPath;

	var agentIsTrapped = isTraped(agent.i, agent.j);

	if (agentIsTrapped) {
		//if true it calls trapDoorSpot to get the trap door Spot.
		console.log("Agent is trapped, RUN to the trap door!");
		var trapDoorSpot = trapDoorLocation(agent.i, agent.j);
		//It calls getAStarPath from developer position to TRAP DOOR position
		aStarPath = getAStarPath(enemy, trapDoorSpot);
	} else {
		//If agentIsNotTrapped is calls getAStarPath from developer to bug position
		aStarPath = getAStarPath(enemy, agent);
	}

	//Should never be in this position. Do not move, to avoid enemy and agent overlap
	if (aStarPath.length == 0 || aStarPath.length == 1) {
		console.log("Illegal move?");
	} else if (aStarPath.length == 2) {
		//We are 1 step away. IF agent is trapped (and autoTrap == true), run to trap door!
		if (agentIsTrapped && autoTrap) {
			var nextStep = aStarPath[1];
			ei = nextStep.i;
			ej = nextStep.j;
		}
	} else {
		//Still far away from the agent. Do the regular AStar Path
		var nextStep = aStarPath[1];
		ei = nextStep.i;
		ej = nextStep.j;
	}

	return aStarPath;
}


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;
	}

	SpotGrid[ai][aj].wall = false;
}




// --- 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 + "   x = (" + x.toString() + ")   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("   y = (" + y.toString() + ") <br>" +
		" Bad steps: " + badsteps +
		"   Good steps: " + goodsteps +
		"   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);
};

function getAStarPath(begin, end) {
	//Given a “begin” and “end” spots
	//Calculate the A Star algorithm from “begin” to “end” 
	//Return the optimal Path of spots, in order, from “begin” to “end”
	
	openSet.push(begin);

	// while has nodes to investigate
	while (openSet.length > 0) {

		var indexBetterF = 0;
		//neighbor with lowest f (previous one can not be in the openset)
		for (var i = 0; i < openSet.length; i++)
			if (openSet[i].f < openSet[indexBetterF].f)
				indexBetterF = i;

		// Best option moves from openSet to closedSet
		var current = openSet[indexBetterF];
		removeFromArray(openSet, current);
		closedSet.push(current);

		// End?
		if (current === end) {
			console.log("success - path found");
			printPath(current);
			return getPath(current);
		}

		// Check all the neighbors
		var neighbors = current.neighbors;

		for (var i = 0; i < neighbors.length; i++) {
			var neighbor = neighbors[i];

			// Valid neighbor?
			if (!closedSet.includes(neighbor) && !neighbor.wall) {

				var tempG = current.g + heuristic(neighbor, current);
				//We could set G directly, but for the nodes in the openSet, they may have an better G than this one.
				//Maybe due a previous attempt that was better than that.

				// Is this a better path than before?
				var isBetterPath = false;

				//Is it the first visit to this Spot?
				var isFirstVist = false;

				//It is not in the openSet, so the only option we have is tempG
				if (!openSet.includes(neighbor)) {
					neighbor.g = tempG;
					isFirstVist = true;
				} else {
					//It is in the open set. We just update neibhbor.g value with tempG if it is better. 
					//In other words, we want the min(neighbor.g, tempG)
					if (tempG < neighbor.g) {
						neighbor.g = tempG;
						isBetterPath = true;
					}
				}

				// Update values if it is a better path (or first visit)
				if (isBetterPath || isFirstVist) {
					neighbor.h = heuristic(neighbor, agent);
					neighbor.f = neighbor.g + neighbor.h;
					neighbor.previous = current;
				}

				//if is the first visit to this neighbor...
				if (!openSet.includes(neighbor))
					openSet.push(neighbor);
			}
		}
	} 
}

function printPath(current) {
	// Find the path by working backwards
	path = [];
	var temp = current;
	path.push(temp);
	while (temp.previous) {
		path.push(temp.previous);
		temp = temp.previous;
	}

	var pathStr = "";
	for (i = path.length - 1; i >= 0; i--) {
		pathStr = pathStr + "(" + path[i].i + "," + path[i].j + ")";
	}

	console.log(pathStr);
}

function getPath(current) {
	// Returns an array of spots, with the A* optimal path in the right order
	path = [];
	var temp = current;
	path.push(temp);
	while (temp.previous) {
		path.push(temp.previous);
		temp = temp.previous;
	}

	var pathInOrder = [];
	for (i = path.length - 1; i >= 0; i--) {
		pathInOrder.push(path[i]);
	}

	return pathInOrder;
	console.log(pathStr);
}


var pathDraw;
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
	var aStarPath = moveLogicalEnemy(); //
	//}

	//Draw the path from developer to agent. 
	var geometry = new THREE.Geometry();
	for (i = 1; i < aStarPath.length; i++) {
		geometry.vertices.push(translate(aStarPath[i].i, aStarPath[i].j));
	}
	var material = new THREE.LineBasicMaterial({ color: 0xffffff });
	var line = new THREE.Line(geometry, material);

	//If keepAllPathsDone == fale draw just the lasf path. 
	if (!keepAllPathsDone)
		ABWorld.scene.remove(pathDraw);

	pathDraw = line;
	ABWorld.scene.add(line);

	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 
}