Code viewer for World: Practical1- Part1: A* to s...

// Cloned by Ayush Bhatt on 29 Oct 2022 from World "Complex World" by Starter user 
// Practical 1 - Part 1 : Applied A* to seek the agent


AB.clockTick       = 80;    

	// 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_WALL 	= '/uploads/maverick/door.png' ;
 const TEXTURE_MAZE 	= '/uploads/maverick/ex4.jpg' ;
 const TEXTURE_AGENT 	= '/uploads/starter/pacman.jpg' ;
 const TEXTURE_ENEMY 	= '/uploads/starter/ghost.3.png' ;
//  const TEXTURE_ENEMY 	= '/uploads/starter/ghost1.jpg' ;

// 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/maverick/sherlock.mp3' ;
	const SOUND_ALARM = '/uploads/maverick/sherlock_end.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) / 6 ); 
		// density of maze - number of internal boxes
		// (bug) use trunc or can get a non-integer 

const squaresize = 50;                                        // 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 * 0.9 ;		// 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 

//  const SKYBOX_ARRAY = [										 
//                 "/uploads/maverick/moondust-xpos.png",
//                 "/uploads/maverick/moondust-xneg.png",
//                 "/uploads/maverick/moondust-ypos.png",
//                 "/uploads/maverick/moondust-yneg.png",
//                 "/uploads/maverick/moondust-zpos.png",
//                 "/uploads/maverick/moondust-zneg.png"
//                 ];

// Ayush Bhatt : Changing in the background to Nebula
 const SKYBOX_ARRAY = [										 
                "/uploads/maverick/nebula-xpos.png",
                "/uploads/maverick/nebula-xneg.png",
                "/uploads/maverick/nebula-ypos.png",
                "/uploads/maverick/nebula-yneg.png",
                "/uploads/maverick/nebula-zpos.png",
                "/uploads/maverick/nebula-zneg.png"
                ];


// ===================================================================================================================
// === End of 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;

// contents of a grid square

const GRID_BLANK 	= 0;
const GRID_WALL 	= 1;

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;

// Variables for A star
var openSet = [];
var closedSet = [];
var start;
var end;
var opencolor = 'lightgreen';
var closedcolor = 'lightpink';
var pathcolor = 'red';
	
function loadResources()		// asynchronous file loads - call initScene() when all finished 
{
	var loader1 = new THREE.TextureLoader();
	var loader2 = new THREE.TextureLoader();
	var loader3 = new THREE.TextureLoader();
	var loader4 = new THREE.TextureLoader();
	
	loader1.load ( TEXTURE_WALL, function ( thetexture )  		
	{
		thetexture.minFilter  = THREE.LinearFilter;
		wall_texture = thetexture;
		if ( asynchFinished() )	initScene();		// if all file loads have returned 
	});
		
	loader2.load ( TEXTURE_AGENT, function ( thetexture )  	 
	{
		thetexture.minFilter  = THREE.LinearFilter;
		agent_texture = thetexture;
		if ( asynchFinished() )	initScene();		 
	});	
	
	loader3.load ( TEXTURE_ENEMY, function ( thetexture )  
	{
		thetexture.minFilter  = THREE.LinearFilter;
		enemy_texture = thetexture;
		if ( asynchFinished() )	initScene();		 
	});
	
	loader4.load ( TEXTURE_MAZE, function ( thetexture )  
	{
		thetexture.minFilter  = THREE.LinearFilter;
		maze_texture = thetexture;
		if ( asynchFinished() )	initScene();		 
	});
	
}


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

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

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

 if ( GRID[i][j].wall == true ) 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 = -180;	
	v.x = ( i * squaresize ) - ( MAXPOS/2 );   		 
	v.z = ( j * squaresize ) - ( MAXPOS/2 );   	
	
	return v;
}



	
function initScene()		// all file loads have returned 
{
	 var i,j, shape, thecube;
	 
	// set up GRID as 2D array
	 
	 for ( i = 0; i < gridsize ; i++ ) 
		GRID[i] = new Array(gridsize);		 


	// set up walls
	 
	 for ( i = 0; i < gridsize ; i++ ) 
	  for ( j = 0; j < gridsize ; j++ ) 
		if ( ( i==0 ) || ( i==gridsize-1 ) || ( j==0 ) || ( j==gridsize-1 ) )
		{
			GRID[i][j] = new Box(i, j, 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] = new Box(i, j, 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].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);		
	}
	 	 
   
	// 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(); 
  // Adding Neighbours to the GRID
   for ( i = 0; i < gridsize; i++)
            for ( j = 0; j < gridsize; j++)
                    GRID[i][j].addNeighbours();
  // Setting start and end variables
    start     = GRID[ei][ej];
    end       = GRID[ai][aj];
    start.wall    = false;
    end.wall      = false;
  // openSet is initialized with start postion.
    openSet.push(start);
    // console.log("initScene openSet", openSet);

  // 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-star implementation by Ayush Bhatt
var original_path = []

class Box{
  constructor(i, j, wall){
  	this.i = i;
  	this.j = j;
  	this.f = 0;
  	this.g = 0;
  	this.h = 0;
  	this.neighbours = [];
  	this.previous = undefined;
  	this.wall = wall;
  }

  checkWall(){
  	return this.wall;
  }

  // Display me
  show(fillColor) 
  {
  	this.shape    = new THREE.BoxGeometry ( squaresize, 1, squaresize );			 
  	this.pathBox = new THREE.Mesh( this.shape );
  	this.pathBox.position.copy(translate(this.i, this.j));
  	this.pathBox.material =  new THREE.MeshBasicMaterial();
  	//ABWorld.scene.add(theagent);
  	this.pathBox.material.color.setColorName(fillColor);
  	ABWorld.scene.add(this.pathBox);
  };

  removePath()
  {
  	ABWorld.scene.remove(this.pathBox);
  }

  addNeighbours()
  {
  	var i = this.i;
  	var j = this.j;
  	
  		if (i < gridsize - 1 && !GRID[i + 1][j].wall) this.neighbours.push(GRID[i + 1][j]);
  		if (i > 0 && !GRID[i - 1][j].wall) this.neighbours.push(GRID[i - 1][j]);
  		if (j < gridsize - 1 && !GRID[i][j + 1].wall)  this.neighbours.push(GRID[i][j + 1]);
  		if (j > 0 && !GRID[i][j - 1].wall) this.neighbours.push(GRID[i][j - 1]);
  };
}

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);
  }

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

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


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

function moveLogicalEnemy()
{ 
// move towards agent 
// put some randomness in so it won't get stuck with barriers 
 resetFunctions();
 var winner = 0;
 let start = GRID[ei][ej];
 let end = GRID[ai][aj];
 
 for (var i = 0; i < original_path.length; i++){
 	original_path[i].removePath(pathcolor);
 	console.log("path[i] remove colour", original_path[i]);
 } 
 
 openSet = [start]
 closedSet = []
 console.log("openSet with only start", openSet);
 var current = null; 
 let path = [];
 
 while(openSet.length > 0){
	console.log("openSet", openSet);
	if (openSet.length > 0) 
	{

    // Best next option
    var winner = 0;
    for (var i = 0; i < openSet.length; i++) 
    	if (openSet[i].f < openSet[winner].f) 
    		winner = i;
    	
    	var current = openSet[winner];

    // Did I finish?
    if (current === end) 
    {
    	console.log("Path Found - SUCCESS");
    	break;
    }

    // Best option moves from openSet to closedSet
    removeFromArray(openSet, current);
    closedSet.push(current);

    // Check all the neighbours
    var neighbours = current.neighbours;
    
    //--- start of for loop -----------
    for (var i = 0; i < neighbours.length; i++) 
    {
    	var neighbor = neighbours[i];

      // Valid next spot?
      if (!closedSet.includes(neighbor) && !neighbor.checkWall()) 
      {
      	var tempG = current.g + heuristic(neighbor, current);

        // Is this a better path than before?
        var newPath = false;
        if (openSet.includes(neighbor)) 
        {
        	if (tempG < neighbor.g) 
        	{
        		neighbor.g = tempG;
        		newPath = true;
        	}
        }
        else 
        {
        	neighbor.g = tempG;
        	newPath = true;
        	openSet.push(neighbor);
        }

        // If it's a better path
        if (newPath) 
        {
        	neighbor.h = heuristic(neighbor, end);
        	neighbor.f = neighbor.g + neighbor.h;
        	neighbor.previous = current;
        }
      }
    }
    //--- end of for loop -----------
    
  }
  // --- end still searching -----------------------------
  else 
  {
  	console.log('fail - no path exists');
  	return;
  }
}
 
// Find the path by working backwards
  
 var temp = current;
 path.push(temp);
 while (temp && temp.previous) 
 {
 	path.push(temp.previous);
 	temp = temp.previous;
 }
 
 original_path = path
 
 for (var i = 0; i < path.length; i++){
 	path[i].show(pathcolor);
//  	console.log("path[i] colour", path[i]);
 } 
 
//  console.log("current location", ei, " ", ej);
//  console.log("path", path);
 
 if(path.length > 2)
 {
 	console.log("path[path.length - 2].i", path[path.length - 2].i);
 	console.log("path[path.length - 2].j", path[path.length - 2].j);
 	i = path[path.length - 2].i;
 	j = path[path.length - 2].j;
 }
 else
 {
 	i = ei;
 	j = ej;
 }
 
 if ( ! occupied(i,j) )  	// if no obstacle then move, else just miss a turn
 {
  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 

  moveLogicalAgent(a);

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


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

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


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

};



AB.world.endRun = function()
{ 
    musicPause(); 
  if ( AB.abortRun ) {
      AB.msg ( " <br> <font color=blue> <B> Game Over!! AGENT got trapped by the ENEMY. </B> </font>   ", 3  );
  }
  else {
      AB.msg ( " <br> <font color=red> <B> Oops!! Times Up!! Please try again. </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 
}