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// Cloned by spandana on 12 Nov 2023 from World "A* assignment-Complex World (clone by spandana)" by spandana 
// Please leave this clone trail here.
 
/*======================================================================================================================
======================================================PRACTICAL 1=======================================================================

STUDENT NAME: SHIVACHARANA SPANDANA DEVARAMANI
STUDENT NUMBER: 23269892

The pirate is the enemy and is trying to capture treassure chest in the maze. 
*/

// Cloned by spandana on 9 Nov 2023 from World "Complex World" by Starter user 
// Please leave this clone trail here.
 
// ==== Starter World =================================================================================================
// This code is designed for use on the Ancient Brain site.
// This code may be freely copied and edited by anyone on the Ancient Brain site.
// To include a working run of this program on another site, see the "Embed code" links provided on Ancient Brain.
// ====================================================================================================================

// =============================================================================================
// 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?

// Speed of run: Step every n milliseconds. Default 100.
    AB.clockTick       = 5;    
    
// Length of run: Maximum length of run in steps. Default 1000.
    AB.maxSteps        = 1000;    

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

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

    // Switch between 3d and 2d view (both using Three.js)
    const show3d = true;						
	
/*============= Spandana======================================================================================
    Credits for the icons and textures used: 
    https://spaceplace.nasa.gov/galaxy/en/
    https://www.vectorstock.com/royalty-free-vector/seamless-wooden-panel-door-texture-with-nails-vector-6318064
    https://www.freepik.com/premium-ai-image/treasure-chest-from-game-pirate-treasure_43903818.htm
    https://www.vectorstock.com/royalty-free-vector/jolly-roger-pirate-flag-vector-4482984
*/    
    
    const TEXTURE_WALL 	= '/uploads/spandana/darkNight.jpg' ;
    const TEXTURE_MAZE 	= '/uploads/spandana/door.jpg' ;
    const TEXTURE_AGENT 	= '/uploads/spandana/treasure-chest-pirate.jpg	';
    const TEXTURE_ENEMY 	= '/uploads/spandana/piratevector.jpg' ;
//=============================================================================================================

    /* credits for the background music and sound:
    https://pixabay.com/music/search/pirate/
    https://pixabay.com/sound-effects/search/pirate/
    */

    const MUSIC_BACK  = '/uploads/spandana/battle-ship-111902.mp3' ;
    const SOUND_ALARM = '/uploads/spandana/piratematt-1-76994.mp3';

    // number of squares along side of world
    const gridsize = 2;	
    
    // density of maze - number of internal boxes
    // (bug) use trunc or can get a non-integer 
    const NOBOXES =  Math.trunc ( (gridsize * gridsize) / 10 );

    // size of square in pixels
    const squaresize = 100;	
    
    // length of one side in pixels    
    const MAXPOS = gridsize * squaresize;
    
    // a number, not a string     
    const SKYCOLOR 	= 0xddffdd;			

    // distance from centre to start the camera at
    const startRadiusConst	 	= MAXPOS * 0.8 ;
    
    // maximum distance from camera we will render things  
    const maxRadiusConst 		= MAXPOS * 10  ;		



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

    ABHandler.MAXCAMERAPOS 	= maxRadiusConst ;

    // "ground" exists at altitude zero
    ABHandler.GROUNDZERO		= true;						



    //--- 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 

/*  ===================================SPANDANA============================
    mountain skybox, credit:
    https://www.freepik.com/free-ai-image/exploring-deep-dark-galaxy-with-astronomy-telescope-satellite-generated-by-ai_48654533.htm

    The downloaded image was converted from HDRI to a cubemap format, credits:
    https://matheowis.github.io/HDRI-to-CubeMap/
*/

    const SKYBOX_ARRAY = [										 
                "/uploads/spandana/galaxy-px.png",
                "/uploads/spandana/galaxy-nx.png",
                "/uploads/spandana/galaxy-py.png",
                "/uploads/spandana/galaxy-ny.png",
                "/uploads/spandana/galaxy-pz.png",
                "/uploads/spandana/galaxy-nz.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;

// 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;
 
    // 3d or 2d box height
    var BOXHEIGHT;		 
    
    // can query GRID about whether squares are occupied, will in fact be initialised as a 2D array   
    var GRID 	= new Array(gridsize);			

    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;

    //=========================SPANDANA : Taken from A Star implementation======================================================
    // credits: https://dev.to/codesphere/pathfinding-with-javascript-the-a-algorithm-3jlb
    
    //declared variables for A Star
    var openSet=[];
    var closeSet=[];
    var start, end;
    var path = [];
    var highlight_path = [];
    var finished = false;

    var badsteps;
    var goodsteps;
    
    // Vertex shader for the gradient material to highlight best route between Pirate and treasure chest
const vertexShader = `
    varying vec2 vUv;

    void main() {
        vUv = uv;
        gl_Position = projectionMatrix * modelViewMatrix * vec4(position, 1.0);
    }
`;

// Fragment shader for the gradient material to highlight best route between Pirate and treasure chest
const fragmentShader = `
    varying vec2 vUv;

    void main() {
        // Define your gradient colors here
        vec3 startColor = vec3(249.0/255.0, 70.0/255.0, 9.0/255.0);  // #f94609
        vec3 endColor = vec3(165.0/255.0, 21.0/255.0, 13.0/255.0);  // #a5150d

        // Interpolate between start and end colors based on the vertical position
        vec3 gradientColor = mix(startColor, endColor, vUv.y);

        gl_FragColor = vec4(gradientColor, 1.0);
    }
`;

// Uniforms for the shader material
const uniforms = {};
    
//==================================================== A star implementation======================================================================
//===========credits: https://dev.to/codesphere/pathfinding-with-javascript-the-a-algorithm-3jlb 
//================================================changes started=======================================================
// Function to remove current point from openSet
function removeElementFromArray(arr, item) 
{
    for (var i = arr.length - 1; i >= 0; i--)
    {
        if (arr[i] == item) 
        {
            arr.splice(i, 1);
        }
    }
}

//Heuristic function to calculate cost - Manhattan distance
function heuristic(a, b) 
{
    return ( Math.abs(a.i - b.i) + Math.abs(a.j - b.j) );
}

//Function to create all the grid points as objects to contain data for the points
function MakeSpot(i, j) 
{
    this.value = 0;

    //location of grid points
    this.i = i;
    this.j = j;

    //initialized heuristic variables
    this.f = 0; //total cost function
    this.g = 0; //cost function from start to the current grid point
    this.h = 0; //heuristic estimated cost function from current grid point to goal point
    
    //neighbors of current grid point
    this.neighbors = [];
    this.previous = undefined;

    //update neighbors of a given grid point
    this.addNeighbors = function(grid) 
    {
        var i = this.i;
        var j = this.j;
        
        if (i < gridsize - 1)   
            this.neighbors.push(grid[i + 1][j]);
        if (i > 0)          
            this.neighbors.push(grid[i - 1][j]);
        if (j < gridsize - 1)   
            this.neighbors.push(grid[i][j + 1]);
        if (j > 0)          
            this.neighbors.push(grid[i][j - 1]);
        //diagonals movement for the Pirate is turned off
        // if (i > 0 && j > 0)
        //     this.neighbors.push(grid[i - 1][j - 1]);
        // if (i < gridsize - 1 && j > 0)          
        //     this.neighbors.push(grid[i + 1][j - 1]);
        // if (i > 0 && j < gridsize - 1)      
        //     this.neighbors.push(grid[i - 1][j + 1]);
        // if (i < gridsize - 1 && j < gridsize - 1)  
        //     this.neighbors.push(grid[i + 1][j + 1]);
    }
}

//function to remove the highlighted path after the Pirate visits the grid point
function removeObject(uuid) 
{
    ABWorld.scene.remove(ABWorld.scene.getObjectByProperty('uuid',uuid));
}

//Function to highlight best path for the Pirate
function highlightPath(path, highlight_path) {
    var gradientMaterial, box;

    if (highlight_path.length > 0) {
        for (const priorId of highlight_path) {
            var tempUUID = priorId;
            removeObject(tempUUID);
        }
        highlight_path.splice(0, highlight_path.length);
    }

    for (var i = 0; i < path.length; i++) {
        // Check if the current point is defined
        if (!path[i]) {
            console.error("Invalid point in path");
            continue;
        }

        // Create a box with a gradient material
        createBoxWithGradient(path[i].i, path[i].j);
    }

    function createBoxWithGradient(i, j) {
        // Create a box geometry
        var boxGeometry = new THREE.BoxGeometry(squaresize, .1, squaresize);

        // Create a gradient material
        gradientMaterial = new THREE.ShaderMaterial({
            uniforms: uniforms,
            vertexShader: vertexShader,
            fragmentShader: fragmentShader,
            side: THREE.BackSide,
        });

        // Create the box mesh with the gradient material
        box = new THREE.Mesh(boxGeometry, gradientMaterial);

        // Position the box at the center of the box
        box.position.copy(translate(i, j));

        // Add the box to the scene
        ABWorld.scene.add(box);

        // Add the box to the drawn path
        highlight_path.push(box.uuid);
    }
}

//A Star implementation to move the Pirate
function aStarAlgorithm() {
    
    //location of the Pirate
    start = GRID[ei][ej];
    
    //location of the treasure chest
    end = GRID[ai][aj];
    
    if (closeSet.length > 0)
        closeSet.splice(0, closeSet.length);
    
    if (openSet.length >  1)
    {
         openSet.splice(0, openSet.length);
         openSet.push(start);
    }
         
    if (path.length > 0)
        path.splice(0, path.length);
    
    while (openSet.length > 0)
    {
        //Assuming lowest index is the first one to begin with
        var lowestindex = 0;
        
        for (var i = 0; i < openSet.length; i++)
        {
            if (openSet[i].f < openSet[lowestindex].f) 
            {    
                lowestindex = i;
            }
        }
            
        var current = openSet[lowestindex];
        
        if (current === end) 
        {   
            var temp = current;
            while(temp.previous != start)
            {
                temp = temp.previous;
                path.push(temp)
            }
            break;
        }
    
        //remove current from openSet
        removeElementFromArray(openSet, current);
        
        //add current to closedSet
        closeSet.push(current);
    
        //check neighbors
        var neighbors = current.neighbors;
        for (var i = 0; i < neighbors.length; i++)
        {
            var neighbor = neighbors[i];    
            
            //check if neighbor is already evaluated
            if (!closeSet.includes(neighbor) && neighbor.value===0) 
            {
                var tempG = current.g + heuristic(neighbor, current);
                
                //check if new path exists
                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 (newPath) 
                {
                    neighbor.h = heuristic(neighbor, end);
                    neighbor.f = neighbor.g + neighbor.h;
                    neighbor.previous = current;
                }
            }
        }
    }
    var i=temp.i;
    var j=temp.j;
    if ( ! occupied(i,j) )  	// if no obstacle then move, else just miss a turn
    {
        ei = i;
        ej = j;
    }
}    
//============================================end of changes===============================================================
//========================================================================================================================================


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 initScene()		
{
	var i,j, shape, thecube;
// =====================================SPANDANA==================================================================================	
//making a 2D grid
	for ( i = 0; i < gridsize ; i++ ) 
	    GRID[i] = new Array(gridsize);		 
    
    for (i = 0; i < gridsize; i++) 
        for (j = 0; j < gridsize; j++) 
            GRID[i][j] = new MakeSpot(i, j);
    
    for (i = 0; i < gridsize; i++) 
        for (j = 0; j < gridsize; j++) 
            GRID[i][j].addNeighbors(GRID);
// ======================================================================================================================================

    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].value = 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].value = GRID_BLANK;
		
   
    for ( var c=1 ; c <= NOBOXES/2 ; c++ )
	{
		i = AB.randomIntAtoB(1,gridsize-2);		// inner squares are 1 to gridsize-1
		j = AB.randomIntAtoB(1,gridsize-2);
			
		GRID[i][j].value = GRID_MAZE ;
		
		shape    = new THREE.BoxGeometry ( squaresize, BOXHEIGHT, squaresize );			 
 		thecylinder  = new THREE.Mesh( shape );
		thecylinder.material = new THREE.MeshBasicMaterial( { map: maze_texture } );		  

		thecylinder.position.copy ( translate(i,j) ); 		  	// translate my (i,j) grid coordinates to three.js (x,y,z) coordinates 
		ABWorld.scene.add(thecylinder);			
	}

	// 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;
	 
//==============================SPANDANA===========================================================
//Initialised openSet to hold the Pirate's intial grid points
	 openSet.push(GRID[ei][ej]);
//===============================================================================================================================	 
	 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;
	 
     closeSet = [];
     
	 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 drawEnemy()		
{
	theenemy.position.copy ( translate(ei,ej) ); 		  	 
	ABWorld.lookat.copy ( theenemy.position );	 		 
}


function drawAgent()		 
{
	theagent.position.copy ( translate(ai,aj) ); 
	ABWorld.follow.copy ( theagent.position );
}

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

//Move the enemy
function moveLogicalEnemy()
{ 
    aStarAlgorithm();
    if (path.length > 0){
        highlightPath(path, highlight_path);
   }
}

//Move the Agent
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=red> <B>Yo-ho-ho, we've struck gold! </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 
}