Code viewer for World: Implementation of A*(clone...

// Cloned by Deval Oza on 8 Nov 2021 from World "Complex World" by Starter user 
// Please leave this clone trail here.


AB.clockTick       = 100;    

	// Speed of run: Step every n milliseconds. Default 100.
	
AB.maxSteps        = 1000;    

	// Length of run: Maximum length of run in steps. Default 1000.

AB.screenshotStep  = 50;   
  
	// Take screenshot on this step. (All resources should have finished loading.) Default 50.



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

const show3d = false;						// Switch between 3d and 2d view (both using Three.js) 

/*----------------------------- ozad2 start -----------------------------------*/ 
 const TEXTURE_WALL 	= '/uploads/ozad2/villa.jpg' ;
 const TEXTURE_MAZE 	= '/uploads/ozad2/brown.jpg' ;
 const TEXTURE_AGENT 	= '/uploads/ozad2/jerry.jpg' ;
 const TEXTURE_ENEMY 	= '/uploads/ozad2/tom.png' ;


const SOUND_ALARM = '/uploads/ozad2/out.wav' ;

/*----------------------------- ozad2 end -----------------------------------*/

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

	
	
/*----------------------------- ozad2 start -----------------------------------*/
const gridsize = 50;						// number of squares along side of world	   


const NOBOXES =  Math.trunc ( (gridsize * gridsize) / 3 );
/*----------------------------- ozad2 end -----------------------------------*/

		// 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 	= 0xffffff;				// 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: -------------------------------

/*----------------------------- ozad2 start -----------------------------------*/
 const SKYBOX_ARRAY = [										 
                "/uploads/ozad2/seabg1.jpg",
                "/uploads/ozad2/seabg2.jpg",
                "/uploads/ozad2/seabg3.jpg",
                "/uploads/ozad2/seabg4.jpg",
                "/uploads/ozad2/seabg5.jpg",
                "/uploads/ozad2/seabg6.jpg"
                ];

/*----------------------------- ozad2 end -----------------------------------*/




//--- 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;
const GRID_MAZE 	= 2;
 
 
 
 

var BOXHEIGHT;		// 3d or 2d box height 

var GRID 	= new Array(gridsize);			// can query GRID about whether squares are occupied, will in fact be initialised as a 2D array   

var theagent, theenemy;
  
var wall_texture, agent_texture, enemy_texture, maze_texture; 


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

var badsteps;
var goodsteps;
// ------------------ ozad2 start ------------------------------------
var path = [];
var openSet = [];
var closedSet = [];
var previousMove = [];
var line = null;
// -------------------- ozad2 end --------------------------------------

	
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
/**
 * Check if position is occupied or not
 * @inputs int i, int j
 * @return boolean
 **/
	
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].type == GRID_WALL ) return true;		// fixed objects	 
 if ( GRID[i][j].type == GRID_MAZE ) return true;		 
	 
 return false;
}

/**
 * translate x, y co-ordinate into x, y, z dimension
 * @inputs int i, int j
 * @return Object
 **/
 // ---------------- ozad2 start --------------------------------
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 will draw a line
 * @inputs int i, int j
 * @return Object
 **/
function drawLine()
{
    if(line != null){
        ABWorld.scene.remove(line);
    }
    var points = [];
    const material = new THREE.LineBasicMaterial( { color: 0x0000ff } );
    console.log(path);
    for (var i=0; i<this.path.length;i++) {
        points.push(translate (this.path[i].i, this.path[i].j));    
    }
    const geometry = new THREE.BufferGeometry().setFromPoints( points );
    line = new THREE.Line( geometry, material );
    ABWorld.scene.add( line );
}

/**
 * calculate distance between two nodes
 * @inputs int startNode, int endNode
 * @return Int
 **/
 
function calculateDistance(startNode, endNode)
{
    return Math.abs(startNode - endNode);   
}
// ---------------- ozad2 end --------------------------------
/**
 * set basic params of grid on provided location and type of grid
 * @inputs string type, int startNode, int endNode
 **/
 // ---------------- ozad2 start --------------------------------
function gridPosition(type, i, j)
{
    // Location
  this.i = i;
  this.j = j;
  this.type = type;
  // f, g, and h values for A*
  this.f = 0;
  this.g = 0;
  this.h = 0;
  // Neighbors
  this.neighbors = [];
    // Where did I come from?
  this.previous = null;
  
  // Figure out who my neighbors are
  this.addNeighbors = function() 
  {
     // console.log('grid');
     // console.log(GRID);
     this.neighbors = [];
    var i = this.i;
    var j = this.j;
    
    if (i < gridsize - 1)   this.neighbors.push(GRID[i + 1][j]);
    if (i - 1 > 0)          this.neighbors.push(GRID[i - 1][j]);
    if (j + 1 < gridsize)   this.neighbors.push(GRID[i][j + 1]);
    if (j - 1 > 0)          this.neighbors.push(GRID[i][j - 1]);
    
  }
  //console.log('neighbour');
  //console.log(this.neighbors);
  
}
// ---------------- ozad2 end --------------------------------
/**
 * Initilise grid
 **/
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;
			//console.log('grid_wall');
			// ---------------------------- ozad2 start ----------------------------------
			GRID[i][j] = new gridPosition(GRID_WALL, i, j); // create wall
			// ---------------------------- ozad2 end ---------------------------------------
			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;
   			// -------------------------------- ozad2 start --------------------------------------
   			GRID[i][j] = new gridPosition(GRID_BLANK, i, j); // create blank gird
   			// ------------------------------- ozad2 end ---------------------------------------

		
   // 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 ;
		// ---------------------- ozad2 start --------------------------------
		GRID[i][j] = new gridPosition(GRID_MAZE, i, j); //create maze 
		// ---------------------- ozad2 end ---------------------------------
		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);
	
	// ---------------- ozad2 start --------------------------------
	// Mark starting position of enemy
	const geometry = new THREE.BoxGeometry( 100, 100, 100 );
    const material = new THREE.MeshBasicMaterial( {color: 0x00ff00} );
    const cube = new THREE.Mesh( geometry, material );
    ABWorld.scene.add( cube );
    cube.position.copy(translate(ei,ej));
    ABWorld.lookat.copy ( cube.position );
    // ---------------- ozad2 end --------------------------------
    
	 //console.log('grid');
	 //console.log(GRID[ej][ej]);
     
	 
	
	// 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);
	
  // 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)
}


// Function to delete element from the array
// ---------------- ozad2 start --------------------------------

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);
}
// ---------------- ozad2 end --------------------------------
/**
 * Calculate heuristic distance
 **/
 // ---------------- ozad2 start --------------------------------
function heuristic(a, b) 
{
    return ( Math.abs(a.i - b.i) + Math.abs(a.j - b.j) );
}
// ---------------- ozad2 end --------------------------------
/**
 * Calculate distance from enemy to agent with the help of A* algorythm
 **/
 // ---------------- ozad2 start --------------------------------
function executeAstarAlgo()
{
    var pathFind = false;
    openSet = [];
    closedSet = [];
    path = [];
    
    
    for(var i = 0;i< gridsize;i++){
        for(var j=0;j<gridsize;j++){
            GRID[i][j].f = 0;
            GRID[i][j].h = 0;
            GRID[i][j].g = 0;
            
            GRID[i][j].previous = null;
            GRID[i][j].addNeighbors();
        }
    }
     
    openSet.push(GRID[ei][ej]);
    var current = null;
    
    while(pathFind == false)
    {
        // Best next option
        var winner = 0;
        if(openSet.length == 0){
            //console.log("no path")
            pathFind = true;
            continue;
        }
        for (var i = 0; i < openSet.length; i++)
          if (openSet[i].f < openSet[winner].f) 
            winner = i;
            current = openSet[winner];
           // console.log(current);
            // Did I finish?
            if (current === GRID[ai][aj]) 
            {
              //noLoop();
              console.log("success - found path");
              //console.log('last');
              pathFind = true;
              continue;
               // path as solid blocks 
            }
        // Best option moves from openSet to closedSet
        //console.log('current')
        //console.log(current)
        removeFromArray(openSet, current);
        closedSet.push(current);
    
        // Check all the neighbors
        var neighbors = current.neighbors;
        //console.log(neighbors)
       // console.log('neighbours');
    //    console.log(current);
        
        //--- start of for loop -----------
        for (var i = 0; i < neighbors.length; i++) 
        {
          var neighbor = neighbors[i];
          
          if(neighbor.type == GRID_WALL || neighbor.type == GRID_MAZE){
              continue;
          }
    
          // Valid next spot?
          if (!closedSet.includes(neighbor)) 
          {
            var tempG = current.g + heuristic(neighbor, current);
            
            //return false;
            // 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);
            }
    
            // Yes, it's a better path
            if (newPath) 
            {
              neighbor.h = heuristic(neighbor, GRID[ai][aj]);
              neighbor.f = neighbor.g + neighbor.h;
              neighbor.previous = current;
            }
          }
        }
        //--- end of for loop -----------
        
      
      // --- end still searching -----------------------------
      
     
  }

  // Find the path by working backwards
  path = [];
  var temp = current;
  path.push(temp);
  while (temp.previous) 
  {
    path.push(temp.previous);
    temp = temp.previous;
  }
  console.log('path');
  console.log(path);
  path = path.reverse();
  drawLine();
}
// ---------------- ozad2 end --------------------------------

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

function moveLogicalEnemy()
{ 
     // ---------------- ozad2 start --------------------------------
    executeAstarAlgo();
    if(path.length <= 1){
        return;
    }
 
 var nextmove = path[1];
 
  if ( ! occupied(nextmove.i, nextmove.j) )  	// if no obstacle then move, else just miss a turn
 {
    ei = nextmove.i;
    ej = nextmove.j;
    previousMove.push(GRID[ei][ej]);   
 }
 // ---------------- ozad2 end --------------------------------
// console.log(calculateDistance(GRID[ei][ej], GRID[ai][aj]));
}


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();
	// ---------------- ozad2 start --------------------------------
	console.log('previousMove');
    console.log(previousMove);
    var points = [];
    //const material = new THREE.LineBasicMaterial( { color: 0x0000ff } );
    const material = new THREE.LineDashedMaterial( {
	color: 0x00FF00,
	linewidth: 1,
	scale: 1,
	dashSize: 3,
	gapSize: 1,
} );
    console.log(path);
    for (var i=0; i<previousMove.length;i++) {
        points.push(translate (previousMove[i].i, previousMove[i].j));    
    }
    const geometry = new THREE.BufferGeometry().setFromPoints( points );
    const line = new THREE.Line( geometry, material );
    ABWorld.scene.add( line );
    // ---------------- ozad2 end --------------------------------
  }

};



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 
}