A userscript-based starter bot for the game TagPro.

exampleBot.user.js

// ==UserScript==
// @name          TagPro Example Bot
// @description   Limited example bot for TagPro.
// @version       0.1
// @grant         none
// @include       http://tagpro-maptest.koalabeast.com:*
// @include       http://tangent.jukejuice.com:*
// @include       http://*.newcompte.fr:*
// @author        Cflakes, snaps_
// @namespace     http://www.reddit.com/user/snaps_
// @license       2015
// ==/UserScript==

/*
 * This function will execute the provided function after tagpro.playerId
 * has been assigned.
 */
function waitForId(fn) {
    // Don't execute the function until tagpro.playerId has been assigned.
    if (!tagpro || !tagpro.playerId) {
        return setTimeout(function() {
            waitForId(fn)
        }, 100);
    } else {
        // Only run the script if we are not spectating.
        if (!tagpro.spectator) {
            fn();
        }
    }
}

// We define everything relevant to our bot inside this function.
function script() {

    // Assign our own player object to `self` for readability.
    var self = tagpro.players[tagpro.playerId];
    
    // Sends key events to move to a destination.
    function move(destination) {
        if (destination.x > 1) {
            tagpro.sendKeyPress("left", true);
            tagpro.sendKeyPress("right", false);
        } else if (destination.x < -1) {
            tagpro.sendKeyPress("right", true);
            tagpro.sendKeyPress("left", false);
        } else {
            tagpro.sendKeyPress("right", true);
            tagpro.sendKeyPress("left", true);
        }
        
        if (destination.y > 1) {
            tagpro.sendKeyPress("up", true);
            tagpro.sendKeyPress("down", false);
        } else if (destination.y < -1) {
            tagpro.sendKeyPress("down", true);
            tagpro.sendKeyPress("up", false);
        } else {
            tagpro.sendKeyPress("up", true);
            tagpro.sendKeyPress("down", true);
        }
    }
    
    // Overriding this function to get a more accurate velocity of players.
    // Velocity is saved in player.vx and vy.
    Box2D.Dynamics.b2Body.prototype.GetLinearVelocity = function() {
        tagpro.players[this.player.id].vx = this.m_linearVelocity.x * 55;
        tagpro.players[this.player.id].vy = this.m_linearVelocity.y * 55;
        return this.m_linearVelocity;
    };
    
    // Returns the position (in pixels) of the flag.
    // Color is a string, one of either: 'red', 'blue', or 'yellow'.
    function findFlag(color) {
        for (var x = 0, xl = tagpro.map.length, yl = tagpro.map[0].length; x < xl; x++) {
            for (var y = 0; y < yl; y++) {
                switch (Math.floor(tagpro.map[x][y])) {
                    case 3:
                        if (color === 'red')
                            return {x: x * 40, y: y * 40};
                        break;
                    case 4:
                        if (color === 'blue')
                            return {x: x * 40, y: y * 40};
                        break;
                    case 16:
                        if (color === 'yellow')
                            return {x: x * 40, y: y * 40};
                        break;
                }
            }
        }
    }
    
    // Returns the enemy FC if in view.
    function enemyFC() {
        for (var id in tagpro.players) {
            if (!tagpro.players.hasOwnProperty(id))
                continue;
            
            var player = tagpro.players[id];
            
            if (player.team === self.team || player.dead || !player.draw)
                continue;
            if (player.flag)
                return player;
        }
    }
    
    /*
     * The logic/flowchart.
     *   If team flag is home, sit on flag.
     *   If team flag is gone, go to enemy team flag.
     *   If an enemy FC is spotted at any time, chase.
     * 
     * Note: There is NO pathfinding.
     */
    function main() {
        requestAnimationFrame(main);
        
        var seek = {},
            enemy = enemyFC(),
            flag = null;
        
        if (enemy) {
            seek.x = (enemy.x + enemy.vx) - (self.x + self.vx);
            seek.y = (enemy.y + enemy.vy) - (self.y + self.vy);
        } else {
            if ((self.team === 1 && tagpro.ui.redFlagTaken) || (self.team === 2 && !tagpro.ui.blueFlagTaken)) {
                flag = findFlag('blue');
            } else {
                flag = findFlag('red');
            }
            if (!flag) {
                flag = findFlag('yellow');
            }
            seek.x = flag.x - (self.x + self.vx);
            seek.y = flag.y - (self.y + self.vy);
        }
        move(seek);
    }
    main();
}

// Initialize the script when tagpro is ready, and additionally wait
// for the playerId property to be assigned.
tagpro.ready(function() {
    waitForId(script);
});