Code viewer for World: 8 game





// =============================================================================================
// More complex starter World for WWM
// 3d-effect Maze World (really a 2-D problem)
// Mark Humphrys, 2016.
//
// 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.
//
// Scoring on the server side is done by taking average of n runs.
// Runs where you get trapped and score zero can seriously affect this score. 
// =============================================================================================






// World must define these:
 
const	 	CLOCKTICK 	= 100;					// speed of run - move things every n milliseconds
const		MAXSTEPS 	= 1000;					// length of a run before final score
 





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

const gridsize = 5;						// number of squares along side of world	   

const NOBOXES =  0//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 BLANKCOLOR 	= SKYCOLOR ;			// make objects this color until texture arrives (from asynchronous file read)




const show3d = true;						// Switch between 3d and 2d view (both using Three.js) 
 
const startRadiusConst	 	= MAXPOS * 0.8 ;		// distance from centre to start the camera at
const skyboxConst			= MAXPOS * 3 ;		// where to put skybox 
const maxRadiusConst 		= MAXPOS * 10  ;		// maximum distance from camera we will render things  





//--- 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;
 
 




 
// --- some useful random functions  -------------------------------------------


function randomfloatAtoB ( A, B )			 
{
 return ( A + ( Math.random() * (B-A) ) );
}

function randomintAtoB ( A, B )			 
{
 return  ( Math.round ( randomfloatAtoB ( A, B ) ) );
}
  
function randomBoolean()			 
{
 if ( Math.random() < 0.5 ) { return false; }
 else { return true; }
}







//---- start of World class -------------------------------------------------------
 
function World() { 


// most of World can be private 
// regular "var" syntax means private variables:


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 WALLS 	= new Array ( 4 * gridsize );		// need to keep handles to wall and maze objects so can find them later to paint them 
var MAZE 	= new Array ( NOBOXES );
var theagent, theenemy;
  
var box1, box2, box3, box4, box5, box6, box7, box8;

var numBoxes = [box1, box2, box3, box4, box5, box6, box7, box8];

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

var badsteps;
var goodsteps;
var  step;

 	var self = this;						// needed for private fn to call public fn - see below  

 


// regular "function" syntax means private functions:


function initGrid()
{
 for (var i = 0; i < gridsize ; i++) 
 {
  GRID[i] = new Array(gridsize);		// each element is an array 

  for (var j = 0; j < gridsize ; j++) 
  {
   GRID[i][j] = GRID_BLANK ;
  }
 }
}

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;
}

 
// 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 ( x ) 
{
 return ( x - ( MAXPOS/2 ) );
}





//--- skybox ----------------------------------------------------------------------------------------------


function initSkybox() 
{

// x,y,z positive and negative faces have to be in certain order in the array 
 
// mountain skybox, credit:
// http://stemkoski.github.io/Three.js/Skybox.html

  var materialArray = [
 	( new THREE.MeshBasicMaterial ( { map: THREE.ImageUtils.loadTexture( "/uploads/starter/dawnmountain-xpos.png" ), side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: THREE.ImageUtils.loadTexture( "/uploads/starter/dawnmountain-xneg.png" ), side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: THREE.ImageUtils.loadTexture( "/uploads/starter/dawnmountain-ypos.png" ), side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: THREE.ImageUtils.loadTexture( "/uploads/starter/dawnmountain-yneg.png" ), side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: THREE.ImageUtils.loadTexture( "/uploads/starter/dawnmountain-zpos.png" ), side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: THREE.ImageUtils.loadTexture( "/uploads/starter/dawnmountain-zneg.png" ), side: THREE.BackSide } ) )
 	];

  var skyGeometry = new THREE.CubeGeometry ( skyboxConst, skyboxConst, skyboxConst );	
  var skyMaterial = new THREE.MeshFaceMaterial ( materialArray );
  var theskybox = new THREE.Mesh ( skyGeometry, skyMaterial );
  threeworld.scene.add( theskybox );						// We are inside a giant cube
}


// This does the file read the old way using loadTexture.
// (todo) Change to asynchronous TextureLoader. A bit complex:
// Make blank skybox. Start 6 asynch file loads to call 6 return functions.
// Each return function checks if all 6 loaded yet. Once all 6 loaded, paint the skybox.		 


  


/*
// --- alternative skyboxes: ------------------------------

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

   var materialArray = [
 	( new THREE.MeshBasicMaterial ( { map: THREE.ImageUtils.loadTexture( "/uploads/starter/sky_pos_z.jpg" ), side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: THREE.ImageUtils.loadTexture( "/uploads/starter/sky_neg_z.jpg" ), side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: THREE.ImageUtils.loadTexture( "/uploads/starter/sky_pos_y.jpg" ), side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: THREE.ImageUtils.loadTexture( "/uploads/starter/sky_neg_y.jpg" ), side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: THREE.ImageUtils.loadTexture( "/uploads/starter/sky_pos_x.jpg" ), side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: THREE.ImageUtils.loadTexture( "/uploads/starter/sky_neg_x.jpg" ), side: THREE.BackSide } ) ),
 	];

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

   var materialArray = [
 	( new THREE.MeshBasicMaterial ( { map: THREE.ImageUtils.loadTexture( "/uploads/starter/posx.jpg" ), side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: THREE.ImageUtils.loadTexture( "/uploads/starter/negx.jpg" ), side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: THREE.ImageUtils.loadTexture( "/uploads/starter/posy.jpg" ), side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: THREE.ImageUtils.loadTexture( "/uploads/starter/negy.jpg" ), side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: THREE.ImageUtils.loadTexture( "/uploads/starter/posz.jpg" ), side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: THREE.ImageUtils.loadTexture( "/uploads/starter/negz.jpg" ), side: THREE.BackSide } ) ),
 	];

*/






// --- asynchronous load textures from file ----------------------------------------
// credits:
// http://commons.wikimedia.org/wiki/File:Old_door_handles.jpg?uselang=en-gb
// 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
  
// loader return can call private function


function loadTextures()
{

 var loader1 = new THREE.TextureLoader();
 loader1.load ( '/uploads/starter/door.jpg',		function ( thetexture ) {			 
		thetexture.minFilter = THREE.LinearFilter;
		paintWalls ( new THREE.MeshBasicMaterial( { map: thetexture } ) );
	} ); 

 var loader2 = new THREE.TextureLoader();
 loader2.load ( '/uploads/starter/latin.jpg',		function ( thetexture ) {			 
		thetexture.minFilter = THREE.LinearFilter;
		paintMaze ( new THREE.MeshBasicMaterial( { map: thetexture } ) );
 	} ); 

 var loader3 = new THREE.TextureLoader();
 loader3.load ( '/uploads/kevin501/3.png',	function ( thetexture ) {			 
		thetexture.minFilter = THREE.LinearFilter;
		theagent.material =  new THREE.MeshBasicMaterial( { map: thetexture } );
	} ); 

 var loader4 = new THREE.TextureLoader();
 loader4.load ( '/uploads/kevin501/2.png',	function ( thetexture ) {			 
		thetexture.minFilter = THREE.LinearFilter;
		theenemy.material =  new THREE.MeshBasicMaterial( { map: thetexture } );
	} ); 
	
	var loader5 = new THREE.TextureLoader();
 loader5.load ( '/uploads/kevin501/number-1-icon.png',	function ( thetexture ) {			 
		thetexture.minFilter = THREE.LinearFilter;
		numBoxes[0].material =  new THREE.MeshBasicMaterial( { map: thetexture } );
	} );
	
	var loader6 = new THREE.TextureLoader();
 loader6.load ( '/uploads/kevin501/2.png',	function ( thetexture ) {			 
		thetexture.minFilter = THREE.LinearFilter;
		numBoxes[1].material =  new THREE.MeshBasicMaterial( { map: thetexture } );
	} );
	
	var loader7 = new THREE.TextureLoader();
 loader7.load ( '/uploads/kevin501/3.png',	function ( thetexture ) {			 
		thetexture.minFilter = THREE.LinearFilter;
		numBoxes[2].material =  new THREE.MeshBasicMaterial( { map: thetexture } );
	} );
	
	var loader8 = new THREE.TextureLoader();
 loader8.load ( '/uploads/kevin501/4.png',	function ( thetexture ) {			 
		thetexture.minFilter = THREE.LinearFilter;
		numBoxes[3].material =  new THREE.MeshBasicMaterial( { map: thetexture } );
	} );
	
	var loader9 = new THREE.TextureLoader();
 loader9.load ( '/uploads/kevin501/5.png',	function ( thetexture ) {			 
		thetexture.minFilter = THREE.LinearFilter;
		numBoxes[4].material =  new THREE.MeshBasicMaterial( { map: thetexture } );
	} );
	
	var loader10 = new THREE.TextureLoader();
 loader10.load ( '/uploads/kevin501/6.png',	function ( thetexture ) {			 
		thetexture.minFilter = THREE.LinearFilter;
		numBoxes[5].material =  new THREE.MeshBasicMaterial( { map: thetexture } );
	} );
	
	var loader11 = new THREE.TextureLoader();
 loader11.load ( '/uploads/kevin501/7.png',	function ( thetexture ) {			 
		thetexture.minFilter = THREE.LinearFilter;
		numBoxes[6].material =  new THREE.MeshBasicMaterial( { map: thetexture } );
	} );
	
	var loader12 = new THREE.TextureLoader();
 loader12.load ( '/uploads/kevin501/8.png',	function ( thetexture ) {			 
		thetexture.minFilter = THREE.LinearFilter;
		numBoxes[7].material =  new THREE.MeshBasicMaterial( { map: thetexture } );
	} );

}


 


// --- add fixed objects ---------------------------------------- 
   
 
function initLogicalWalls()		// set up logical walls in data structure, whether doing graphical run or not	
{
 for (var i = 0; i < gridsize ; i++) 
  for (var j = 0; j < gridsize ; j++) 
   if ( ( i==0 ) || ( i==gridsize-1 ) || ( j==0 ) || ( j==gridsize-1 ) )
   {
    	GRID[i][j] = GRID_WALL ;		 
   }
}


function initThreeWalls()		// graphical run only, set up blank boxes, painted later 	
{
 var t = 0;
 for (var i = 0; i < gridsize ; i++) 
  for (var j = 0; j < gridsize ; j++) 
   if ( GRID[i][j] == GRID_WALL )
   {
 	 var shape    = new THREE.BoxGeometry( squaresize, BOXHEIGHT, squaresize );			 
 	 var thecube  = new THREE.Mesh( shape );
	 thecube.material.color.setHex( BLANKCOLOR  );			  
 
    	 thecube.position.x = translate ( i * squaresize );   		// translate my simple (i,j) block-numbering coordinates to three.js (x,y,z) coordinates 
    	 thecube.position.z = translate ( j * squaresize );   	
    	 thecube.position.y =  0;	
 
 	 threeworld.scene.add(thecube);
	 WALLS[t] = thecube;				// save it for later
	 t++; 
   }
}


function paintWalls ( material )		 
{
 for ( var i = 0; i < WALLS.length; i++ )
 { 
   if ( WALLS[i] )  WALLS[i].material = material;
 }
}





function initLogicalMaze()		 
{
 for ( var c=1 ; c <= NOBOXES ; c++ )
 {
  	var i = randomintAtoB(1,gridsize-2);	// inner squares are 1 to gridsize-2
  	var j = randomintAtoB(1,gridsize-2);
    	GRID[i][j] = GRID_MAZE ;		 
 }
}

var numsOut = new Array(9);
 var count = 0;
 var randomPos;
 var shape ;
 
 var gridPos = new Array(3);
 function initGridPos()
{
 for (var i = 0; i < gridsize ; i++) 
 {
  gridPos[i] = new Array(3);		// each element is an array 

  for (var j = 0; j < gridsize ; j++) 
  {
   gridPos[i][j] = GRID_BLANK ;
  }
 }
}

function initRandomPositions(){
    
    for(var i = 1; i < 4; i++){
        
        for (var j = 1; j < gridsize-1 ; j++) {
         
         shape    = new THREE.BoxGeometry( squaresize, BOXHEIGHT, squaresize );
         //ensure the same card aint drawn twice
         while(true){
              randomPos = randomintAtoB(0,8); 
             
             if(numsOut.indexOf(randomPos) == -1)
                break;
         }
         numsOut[count] = randomPos;
         count++;
         
         numBoxes[randomPos] = new THREE.Mesh( shape );          
         numBoxes[randomPos].material.color.setHex( BLANKCOLOR  );
         
         gridPos[i][j] = numBoxes[randomPos];
         console.log(gridPos[i][j]);
        gridPos[i][j].position.x = translate ( i * squaresize );   	
  	    gridPos[i][j].position.z = translate ( j * squaresize );   	
  	    gridPos[i][j].position.y =  0;	
        
        threeworld.scene.add(gridPos[i][j]);
         //drawBoxNum(numBoxes[randomPos]);
         
        }
    }
}

/*
function initRandomPositions(){
    var shape    = new THREE.BoxGeometry( squaresize, BOXHEIGHT, squaresize );			 
 	 numBoxes[5]  = new THREE.Mesh( shape );
	 numBoxes[5].material.color.setHex( BLANKCOLOR  );			  
        
        var i =2, j = 2;
    	 numBoxes[5].position.x = translate ( i * squaresize );   		// translate my simple (i,j) block-numbering coordinates to three.js (x,y,z) coordinates 
    	 numBoxes[5].position.z = translate ( j * squaresize );   	
    	 numBoxes[5].position.y =  0;	
 
 	 threeworld.scene.add(numBoxes[5]);
}*/


function initThreeMaze()		  	
{
 var t = 0;
 for (var i = 0; i < gridsize ; i++) 
  for (var j = 0; j < gridsize ; j++) 
   if ( GRID[i][j] == GRID_MAZE )
   {
   	var shape    = new THREE.BoxGeometry( squaresize, BOXHEIGHT, squaresize );			 
  	var thecube  = new THREE.Mesh( shape );
	thecube.material.color.setHex( BLANKCOLOR  );			  

  	thecube.position.x = translate ( i * squaresize );   	
  	thecube.position.z = translate ( j * squaresize );   	
  	thecube.position.y =  0;	
 
 	threeworld.scene.add(thecube);
	MAZE[t] = thecube;		// save it for later
	t++; 
   }
}


function paintMaze ( material )		 
{
 for ( var i = 0; i < MAZE.length; i++ )
 { 
   if ( MAZE[i] )  MAZE[i].material = material;
 }
}







// --- enemy functions -----------------------------------


function drawEnemy(a)	// given ei, ej, draw it 
{
  var x = translate ( ei * squaresize );   	
  var z = translate ( ej * squaresize );   	
  var y =  0;	

 /*theenemy.position.x = x;
 theenemy.position.y = y;
 theenemy.position.z = z;
 threeworld.scene.add(theenemy);

 threeworld.lookat.copy ( theenemy.position );		// if camera moving, look back at where the enemy is  
 */
 a.position.x = x;
 a.position.y = y;
 a.position.z = z;
 threeworld.scene.add(a);

 threeworld.lookat.copy ( a.position );
}


function initLogicalEnemy()
{
// start in random location:
 var i, j;
 do
 {
  i = randomintAtoB(1,gridsize-2);
  j = randomintAtoB(1,gridsize-2);
 }
 while ( occupied(i,j) );  	  // search for empty square 

 ei = i;
 ej = j;
}


function initThreeEnemy()
{
/* var shape    = new THREE.BoxGeometry( squaresize, BOXHEIGHT, squaresize );			 
 theenemy = new THREE.Mesh( shape );
 theenemy.material.color.setHex( BLANKCOLOR  );	
 drawEnemy();*/
 
 var shape    = new THREE.BoxGeometry( squaresize, BOXHEIGHT, squaresize );			 
 numBoxes[3] = new THREE.Mesh( shape );
 numBoxes[3].material.color.setHex( BLANKCOLOR  );	
 drawEnemy(numBoxes[3]);
}


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

 var i, j;
 if ( ei < ai ) i = randomintAtoB(ei, ei+1); 
 if ( ei == ai ) i = ei; 
 if ( ei > ai ) i = randomintAtoB(ei-1, ei); 

 if ( ej < aj ) j = randomintAtoB(ej, ej+1); 
 if ( ej == aj ) j = ej; 
 if ( ej > aj ) j = randomintAtoB(ej-1, ej); 
 
 if ( ! occupied(i,j) )  	// if no obstacle then move, else just miss a turn
 {
  ei = i;
  ej = j;
 }
}





// --- agent functions -----------------------------------


function drawAgent()	// given ai, aj, draw it 
{
  var x = translate ( ai * squaresize );   	
  var z = translate ( aj * squaresize );   	
  var y =  0;	

 theagent.position.x = x;
 theagent.position.y = y;
 theagent.position.z = z;
 threeworld.scene.add(theagent);

 threeworld.follow.copy ( theagent.position );		// follow vector = agent position (for camera following agent)
}


function initLogicalAgent()
{
// start in random location:
 var i, j;
 do
 {
  i = randomintAtoB(1,gridsize-2);
  j = randomintAtoB(1,gridsize-2);
 }
 while ( occupied(i,j) );  	  // search for empty square 

 ai = i;
 aj = j;
}

function initThreeAgent()
{
 var shape    = new THREE.BoxGeometry( squaresize, BOXHEIGHT, squaresize );			 
 theagent = new THREE.Mesh( shape );
 theagent.material.color.setHex( BLANKCOLOR );	
 drawAgent(); 		  
}

function moveBox(a){
    var i = 2;
    var j = 2;
    
    var abox = gridPos[i][j];
    
    //gridPos[i][j] = null;
    if ( a == ACTION_LEFT ) 	i--;
 else if ( a == ACTION_RIGHT ) 	i++;
 else if ( a == ACTION_UP ) 		j++;
 else if ( a == ACTION_DOWN ) 	j--;
 //var temp boxmove = grid[i][j];
 
    var x = translate ( i * squaresize );   	
     var z = translate ( j * squaresize );   	
     var y =  0;	
    // var shape    = new THREE.BoxGeometry( squaresize, BOXHEIGHT, squaresize );			 
    //abox = new THREE.Mesh( shape );
    //abox.material.color.setHex( BLANKCOLOR );
    //gridPos[i][j] = null;
     abox.position.x = x;
     abox.position.y = y;
     abox.position.z = z;
     abox.scene.add(abox);
 
 
}


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;
 }
}



function keyHandler(e)		
// user control 
// Note that this.takeAction(a) is constantly running at same time, redrawing the screen.
{
   /* if (e.keyCode == 37)  moveLogicalAgent ( ACTION_LEFT 	);
    if (e.keyCode == 38)  moveLogicalAgent ( ACTION_DOWN  	);
    if (e.keyCode == 39)  moveLogicalAgent ( ACTION_RIGHT 	);
    if (e.keyCode == 40)  moveLogicalAgent ( ACTION_UP	);*/
    
    if (e.keyCode == 37)  moveBox ( ACTION_LEFT 	);
    if (e.keyCode == 38)  moveBox ( ACTION_DOWN  	);
    if (e.keyCode == 39)  moveBox ( ACTION_RIGHT 	);
    if (e.keyCode == 40)  moveBox ( ACTION_UP	);
}





// --- 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 = self.getState();
 var status = " Step: <b> " + step + " </b> &nbsp; x = (" + x.toString() + ") &nbsp; a = (" + a + ") "; 

 $("#user_span3").html( status );
}


function   updateStatusAfter()		// agent and enemy have moved, can calculate score
{
 // new state after both have moved
 var y = self.getState();
 var status = " &nbsp; y = (" + y.toString() + ") <BR> "; 
 $("#user_span4").html( status );

 var score = self.getScore();

 var status = "   Bad steps: " + badsteps + 
		" &nbsp; Good steps: " + goodsteps + 
		" &nbsp; Score: " + score.toFixed(2) + "% "; 

 $("#user_span5").html( status );
}






//--- public functions / interface / API ----------------------------------------------------------


	this.endCondition;			// If set to true, run will end. 



this.newRun = function() 
{

// (subtle bug) must reset variables like these inside newRun (in case do multiple runs)

  this.endCondition = false;
  badsteps = 0;	
  goodsteps = 0;
	step = 0;


 // for all runs:
    initGridPos();
 	initGrid();
	initLogicalWalls(); 
	initLogicalMaze();
	//initLogicalAgent();
//	initLogicalEnemy();
    //initRandomPositions()
    
 // for graphical runs only:

  if ( true  )
  {
	if ( show3d )
	{
	 BOXHEIGHT = squaresize;
	 threeworld.init3d ( startRadiusConst, maxRadiusConst, SKYCOLOR  ); 	
	}	     
	else
	{
	 BOXHEIGHT = 1;
	 threeworld.init2d ( startRadiusConst, maxRadiusConst, SKYCOLOR  ); 		     
	}

	initSkybox();
 	initMusic();

	// Set up objects first:

	initThreeWalls(); 
	initThreeMaze();
	//initThreeAgent();
	//initThreeEnemy();
	initRandomPositions()
	//

	// Then paint them with textures - asynchronous load of textures from files. 
	// The texture file loads return at some unknown future time in some unknown order.
	// Because of the unknown order, it is probably best to make objects first and later paint them, rather than have the objects made when the file reads return.
	// It is safe to paint objects in random order, but might not be safe to create objects in random order. 

	loadTextures();	

	document.onkeydown = keyHandler;	 
  }

};




this.getState = function()
{
 var x = [ ai, aj, ei, ej ];
  return ( x );  
};



this.takeAction = function ( a )
{
  step++;

  if ( true  )
   updateStatusBefore(a);			// show status line before moves 

  moveLogicalAgent(a);

  if ( ( step % 2 ) == 0 )		// slow the enemy down to every nth step
    moveLogicalEnemy();


  if ( badstep() )
   badsteps++;
  else
   goodsteps++;

  if ( true  )
  {
  // drawAgent();
   //drawEnemy();
   moveBox();
   updateStatusAfter();			// show status line after moves  
  }


  if ( agentBlocked() )			// if agent blocked in, run over 
  {
	this.endCondition = true;
	goodsteps = 0;			// you score zero as far as database is concerned 			 
  	if ( true  )
  	{
	 musicPause();
	 soundAlarm();
	}
  }

};



this.endRun = function()
{
 if ( true  )
 {
  musicPause(); 
  if ( this.endCondition )
    $("#user_span6").html( " &nbsp; <font color=red> <B> Agent trapped. Final score zero. </B> </font>   "  );
  else
    $("#user_span6").html( " &nbsp; <font color=red> <B> Run over. </B> </font>   "  );
 }
};


this.getScore = function()
{
 return ( ( goodsteps / step ) * 100 );
};


}

//---- end of World class -------------------------------------------------------








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



function initMusic()
{
	// put music element in one of the spans
  	var x = "<audio  id=theaudio  src=/uploads/starter/Defense.Line.mp3   autoplay loop> </audio>" ;
  	$("#user_span1").html( x );
} 
 

function musicPlay()  
{
	// jQuery does not seem to parse pause() etc. so find the element the old way:
 	document.getElementById('theaudio').play();
}


function musicPause() 
{
 	document.getElementById('theaudio').pause();
}


function soundAlarm()
{
 	var x = "<audio    src=/uploads/starter/air.horn.mp3   autoplay  > </audio>";
  	$("#user_span2").html( x );
}