Code viewer for World: Expo World
 
// - Internal maze (randomly drawn each time)
// - Enemy actively chases agent


const CHANGESTEP = 200;      // change music/skybox/etc. every n steps 


// ======================================================================================================
// 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 get BLOCKPUNISH bad steps and the problem is reset - enemy is moved to a random square
// ======================================================================================================

const BLOCKPUNISH = 50;



//--- 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)







// ===================================================================================================================
// === Start of tweaker's box ======================================================================================== 
// ===================================================================================================================

// The easiest things to modify are in this box.


AB.clockTick       = 50;    

	// Speed of run: Step every n milliseconds. Default 100.
	
AB.maxSteps        = 10000000;    

	// 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 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 SOUND_ALARM = '/uploads/starter/air.horn.mp3' ;

// http://soundbible.com/1542-Air-Horn.html 

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

const BOXDENSITY = 0.1;
const NOBOXES =  Math.trunc ( (gridsize * gridsize) * BOXDENSITY );
		// 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 skyboxConst			= MAXPOS * 2 ;		// where to put skybox 
const maxRadiusConst 		= MAXPOS * 10  ;		// maximum distance from camera we will render things  



//--- change ABWorld defaults: -------------------------------

ABHandler.MAXCAMERAPOS 	= skyboxConst * 0.6 ;			// keep camera inside skybox 

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 
 
// mountain skybox, credit:
// http://stemkoski.github.io/Three.js/Skybox.html
 
 const SKYBOX2_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 SKYBOX3_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"
                ];


 const SKYBOX_ARRAY = [										 
                "/uploads/starter/st.posx.jpg",
                "/uploads/starter/st.negx.jpg",
                "/uploads/starter/st.posy.jpg",
                "/uploads/starter/st.negy.jpg",
                "/uploads/starter/st.posz.jpg",
                "/uploads/starter/st.negz.jpg"
                ];


// https://www.dl-sounds.com/royalty-free/category/game-film/video-game/

  const music_array  = [
      '/uploads/starter/Defense.Line.mp3',
 //     '/uploads/test/IntroScreen.mp3',
 //     '/uploads/test/OffLimits.wav',
      '/uploads/test/Platformer2.mp3',
      '/uploads/test/PowerBotsLoop.wav',
      '/uploads/test/StarCommander1.wav'
      ];

// ===================================================================================================================
// === End of tweaker's box ==========================================================================================
// ===================================================================================================================






// contents of a grid square

const GRID_BLANK 	= 0;
const GRID_WALL 	= 1;
const GRID_MAZE 	= 2;
 
 




var BOXHEIGHT  = squaresize;

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; 
var skybox_texture_array = new Array ( 6 );	    	// a cube 
var skybox2_texture_array = new Array ( 6 );		// a cube 
var skybox3_texture_array = new Array ( 6 );		// a cube 
var theskybox;
	var skyGeometry, skyMaterial, skyMaterial2, skyMaterial3;


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

var badsteps;
var goodsteps;

var stuckfor = 0;       // how long the enemy has been stuck - if stuck for a while start making random moves 

 
 

	
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();		 
	});
	
	var i;
	for (   i = 0; i < 6; i++ ) 
	  skyboxFileLoad ( i );						// launch 6 more asynchronous file loads for skybox 
	for (   i = 0; i < 6; i++ ) 
	  skybox2FileLoad ( i );						// launch 6 more asynchronous file loads for skybox 
	for (   i = 0; i < 6; i++ ) 
	  skybox3FileLoad ( i );						// launch 6 more asynchronous file loads for skybox 
}


function skyboxFileLoad ( n )				// asynchronous file load of skybox texture n 
{
	var loader = new THREE.TextureLoader();

	loader.load ( SKYBOX_ARRAY[n], function ( thetexture )  	 
	{
		thetexture.minFilter  = THREE.LinearFilter;
		skybox_texture_array[n] = thetexture;
		if ( asynchFinished() ) initScene();
	});	
}

function skybox2FileLoad ( n )				// asynchronous file load of skybox texture n 
{
	var loader = new THREE.TextureLoader();

	loader.load ( SKYBOX2_ARRAY[n], function ( thetexture )  	 
	{
		thetexture.minFilter  = THREE.LinearFilter;
		skybox2_texture_array[n] = thetexture;
		if ( asynchFinished() ) initScene();
	});	
}

function skybox3FileLoad ( n )				// asynchronous file load of skybox texture n 
{
	var loader = new THREE.TextureLoader();

	loader.load ( SKYBOX3_ARRAY[n], function ( thetexture )  	 
	{
		thetexture.minFilter  = THREE.LinearFilter;
		skybox3_texture_array[n] = thetexture;
		if ( asynchFinished() ) initScene();
	});	
}

function asynchFinished()		 // all file loads returned 
{
    var i;
	for (   i = 0; i < 6; i++ ) 
		if ( ! skybox_texture_array[i] ) 
			return false;
			
	for (   i = 0; i < 6; i++ ) 
		if ( ! skybox2_texture_array[i] ) 
			return false;
			
	for (   i = 0; i < 6; i++ ) 
		if ( ! skybox3_texture_array[i] ) 
			return false;
		
	// else 
	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;
}



	
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
	 resetEnemyPos();
	 
	 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(); 


	
  skyGeometry = new THREE.CubeGeometry ( skyboxConst, skyboxConst, skyboxConst );
  
  var skybox_material_array = [
 	( new THREE.MeshBasicMaterial ( { map: skybox_texture_array[0], side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: skybox_texture_array[1], side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: skybox_texture_array[2], side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: skybox_texture_array[3], side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: skybox_texture_array[4], side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: skybox_texture_array[5], side: THREE.BackSide } ) )
 	];
  var skybox2_material_array = [
 	( new THREE.MeshBasicMaterial ( { map: skybox2_texture_array[0], side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: skybox2_texture_array[1], side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: skybox2_texture_array[2], side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: skybox2_texture_array[3], side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: skybox2_texture_array[4], side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: skybox2_texture_array[5], side: THREE.BackSide } ) )
 	];
  var skybox3_material_array = [
 	( new THREE.MeshBasicMaterial ( { map: skybox3_texture_array[0], side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: skybox3_texture_array[1], side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: skybox3_texture_array[2], side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: skybox3_texture_array[3], side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: skybox3_texture_array[4], side: THREE.BackSide } ) ),
 	( new THREE.MeshBasicMaterial ( { map: skybox3_texture_array[5], side: THREE.BackSide } ) )
 	];
 	
 	
  skyMaterial = new THREE.MeshFaceMaterial ( skybox_material_array );
  skyMaterial2 = new THREE.MeshFaceMaterial ( skybox2_material_array );
  skyMaterial3 = new THREE.MeshFaceMaterial ( skybox3_material_array );
 
	 randomSkybox();


 
  // can start the run loop
  
	ABWorld.render();		
  
	AB.removeLoading();
	
  	AB.runReady = true; 			
}
 
 
 	 
function 	 randomSkybox()
{
    if ( typeof theskybox != 'undefined' )
        ABWorld.scene.remove( theskybox );
    
 var m = AB.randomPick3 ( skyMaterial, skyMaterial2, skyMaterial3 );
    theskybox = new THREE.Mesh ( skyGeometry, m );

//  theskybox.position.y = skyboxConst * 0.4  ;
  
  ABWorld.scene.add( theskybox );						 
}

 
function resetEnemyPos()
{
     var i,j;	 
     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;
}





// --- 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 getEnemyAction()
{ 
// move towards agent 
 
  // after n failed moves, start making random moves 
  if ( stuckfor > 2 ) return  ( AB.randomIntAtoB (0,3) );


if ( AB.randomBoolean() )
{
     if ( ej < aj ) 	return (   ACTION_UP ); 
	 if ( ej > aj ) 	return (   ACTION_DOWN ); 
}
else
{
	 if ( ei < ai ) 	return (   ACTION_RIGHT ); 
	 if ( ei > ai ) 	return (   ACTION_LEFT ); 
}

 	return  ( AB.randomIntAtoB (0,3) );
}



function moveLogicalEnemy( a )			 
{ 
 var i = ei;
 var j = ej;		 

      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) ) 
  stuckfor++;
 else
 {
  stuckfor = 0;
  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;
 }
}




// --- 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 
{
 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();
 
 var status = " Step: " + AB.step + 
			" &nbsp; x = (" + x.toString() + ") " +
			" &nbsp; a = (" + a + ") "; 

 AB.msg ( status );
}


function   updateStatusAfter()		// agent and enemy have moved, can calculate score
{
 // new state after both have moved
 
 var y 		= AB.world.getState();

 var score = ( goodsteps / AB.step ) * 100; 

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

 AB.msg ( status, 2 );
}






AB.world.newRun = function() 
{
	AB.loadingScreen();

	AB.runReady = false;  

	badsteps = 0;	
	goodsteps = 0;
	  randomMusic();

	 ABWorld.init3d ( startRadiusConst, maxRadiusConst, SKYCOLOR  ); 	
	loadResources();		// aynch file loads		
							// calls initScene() when it returns 

};




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




AB.world.takeAction = function ( a )
{
  updateStatusBefore(a);			// show status line before moves 

  moveLogicalAgent(a);

  if ( ( AB.step % 2 ) == 0 )		// slow the enemy down to every nth step
  {
      var e = getEnemyAction();
      moveLogicalEnemy(e);
  }


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

   drawAgent();
   drawEnemy();
   updateStatusAfter();			// show status line after moves  



 if ( ( AB.step % CHANGESTEP ) == 0 )
 {
      if (AB.randomBoolean())   randomSkybox();
      else
      {
        if (AB.randomBoolean()) randomMusic();
	    else   randomCamera();
      }
 }
 
else   if ( agentBlocked() )			// if agent blocked in, you get BLOCKPUNISH bad steps and the problem is reset  
  {
    badsteps = badsteps + BLOCKPUNISH;
    AB.step = AB.step + BLOCKPUNISH;
    AB.msg ( " <br> <font color=red> <B> Agent blocked. " + BLOCKPUNISH + " extra bad steps and reset enemy. </B> </font>   ", 3  );
 // randomMusic();
 //soundAlarm();
    // enemy is moved to a random square
     resetEnemyPos();
  }
  
};




AB.world.endRun = function()
{
  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
};





var cameranow = "fixed";

function randomCamera()
{
    // rotate around 3 views:
    
 if ( cameranow == "fixed" )
 {
     ABWorld.cameraTrack()
     cameranow = "track";
 }
 else  if ( cameranow == "track" )
 {
      ABWorld.cameraMove()
     cameranow = "move";
 }
 else  if ( cameranow == "move" ) 
 {
     ABWorld.cameraFixed()
     cameranow = "fixed";
 }

}



var backmusic; 


function randomMusic()
{
 if ( typeof backmusic != 'undefined' ) musicPause();
 backmusic = new Audio ( AB.randomElementOfArray ( music_array ) );
        backmusic.loop = true;                 // loop forever 
        backmusic.play();
} 
 
        
function musicPlay()   { backmusic.play();  }
function musicPause()  { backmusic.pause(); }

                                                                                         
function soundAlarm()
{
        var alarm = new Audio ( SOUND_ALARM );
        alarm.play();                                                   // play once, no loop 
}