Code viewer for World: Finding Nemo


// Cloned by Sean O Malley on 3rd Nov 2019 from World "Complex World" by Starter user
// Please leave this clone trail here.

/* DOCUMENTATION HERE */




// ==== Starter World ===============================================================================================
// (c) Ancient Brain Ltd. All rights reserved.
// This code is only for use on the Ancient Brain site.
// This code may be freely copied and edited by anyone on the Ancient Brain site.
// This code may not be copied, re-published or used on any other website.
// To include a run of this code on another website, see the "Embed code" links provided on the Ancient Brain site.
// ==================================================================================================================



// =============================================================================================
// 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?
AB.clockTick = 200;
// Speed of run: Step every n milliseconds. Default 100.
// Slow down to see A* in action


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/somalley/green.png';
const TEXTURE_MAZE = '/uploads/somalley/buoy.png';
const TEXTURE_AGENT = '/uploads/somalley/fish.png';
const TEXTURE_ENEMY = '/uploads/somalley/shark.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 MUSIC_BACK  = '/uploads/somalley/Jaws-theme-song.mp3' ;
const SOUND_ALARM = '/uploads/starter/air.horn.mp3' ;


const gridsize = 20; // number of squares along side of world      
const NOBOXES = Math.trunc((gridsize * gridsize) /10); // density of maze - number of internal boxes
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 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
// x,y,z positive and negative faces have to be in certain order in the array
// https://threejs.org/docs/#api/en/loaders/CubeTextureLoader

// mountain skybox, credit:
// http://stemkoski.github.io/Three.js/Skybox.html

const SKYBOX_ARRAY = [
    "/uploads/somalley/heather_lf.jpg",
    "/uploads/somalley/heather_lf.jpg",
    "/uploads/somalley/heather_lf.jpg",
    "/uploads/somalley/heather_lf.jpg",
    "/uploads/somalley/heather_lf.jpg",
    "/uploads/somalley/heather_lf.jpg"
];


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


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


// You will need to be some sort of JavaScript programmer to change things below the 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;


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;


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].type == GRID_WALL) return true; // fixed objects      
    if (GRID[i][j].type == 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 createGrid(gridSize)
{

    var grid = new Array(gridSize);

    // set up GRID as 2D array
    for (i = 0; i < gridsize; i++)
        grid[i] = new Array(gridsize);


     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 Spot(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] = new Spot(i, j, GRID_BLANK);
    }


    // Create 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] = new Spot(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);
    }

   
    for (var i = 0; i < gridsize; i++)
        for (var j = 0; j < gridsize; j++)
        {
            grid[i][j].addNeighbors(grid);
        
    }

    return grid;
}


function initScene() // all file loads have returned
{
    var i, j, shape, thecube;


    GRID = createGrid(this.gridSize);

    // 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();


    // 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)
}


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

//=== heuristic ===========================



// this must be always optimistic - real time will be this or longer 
// An educated guess of how far it is between two points
function heuristic(a, b)
{
    var d1 = new THREE.Vector3(a.i, 0, a.j);
    var d2 = new THREE.Vector3(b.i, 0, b.j);
    
    //Manhattan Distance
    return d1.manhattanDistanceTo (d2);
    
    //return d1.distanceToSquared(d2)
    
}

// Remove an element from array
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);
}



// An object to describe a spot in the grid
function Spot(i, j, type)
{

    // Location
    this.i = i;
    this.j = j;

    // f, g, and h values for A*
    this.f = 0;
    this.g = 0;
    this.h = 0;

    // Neighbors
    this.neighbors = [];



    this.type = type;
    
    
    

  // Where did I come from?
 this.previous = undefined;



  // Am I an wall?
  //this.wall = false;
  //if (random(1) < 0.4) {
    //this.wall = true;
  //}


    // Figure out who my neighbors are
    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]);

        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 findNeighbor(start, end)
{

    var openSet = [];
    var closedSet = [];

    openSet.push(start);
    var current;

    while (openSet.length > 0)
    {
        var winner = 0;

        current = openSet[0];

        removeFromArray(openSet, current);
        closedSet.push(current);

        var neighbors = current.neighbors;

        //--- start of for loop -----------
        for (i = 0; i < neighbors.length; i++)
        {
            var neighbor = neighbors[i];
            

            if (!closedSet.includes(neighbor) && neighbor.type == GRID_BLANK)
            {
                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);
                }

                // Yes, it's a better path
                if (newPath)
                {
                    neighbor.h = heuristic(neighbor, end);
                    neighbor.f = neighbor.g + neighbor.h;
                    neighbor.previous = current;
                }
            }            
           
            // Check if this is our goal
            if (neighbor === end)
            {
                console.log("success - found path");
                while (end.previous)
                {
                    if (end.previous === start)
                        {
                            break;
                        }
                    end = end.previous;
                }
                return end;
    
            }
        }
    }

    // We couldn't find a path, skip
    console.log("fail - no path found");
    return start;
}


// Here is where our enemy takes their move
function moveLogicalEnemy()
{
    var agent = GRID[ai][aj];
    var enemy = GRID[ei][ej];
    var goToNeighbor = findNeighbor(enemy, agent);

 
    ei = goToNeighbor.i;
    ej = goToNeighbor.j;
}

//The agent could use an alternative heuristic here to counter the enemy
// One solution could be to find a path to a point beside the walls of the maze that lies furthest away from the enemy
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 + "   x = (" + x.toString() + ")   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("   y = (" + y.toString() + ") <br>" +
        " Bad steps: " + badsteps +
        "   Good steps: " + goodsteps +
        "   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> 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
 }