multiplayer-canvas/client/examplegame.js

function ExampleGame(connection) {
	var game = null;
	var system = null;

	var player = null;
	var otherPlayers = [];

	var keyboard = null;
	var camera = {x: 0, y: 0, speed: 5};

	this.init = function(systemObject, canvas) {
		game = this;
		system = systemObject;

		keyboard = new KeyboardInput();
		keyboard.attach();

		camera = {x: 0, y: 0, speed: 5};

		var defaultData = {
			position: {x: 60, y: 60},
			velocity:  {x: 0, y: 0},
			moveToTarget: false,
			targetDestination: {x: 60, y: 60},
			targetAngle: 0,
			shipColor: "#DD0000"
		};
		
		player = new Player(camera, defaultData);
	};

	this.sendMessage = function(data) {
		connection.send(JSON.stringify(data, null, "\t"));
	}

	this.receiveMessage = function(data) {
		if(data.hasOwnProperty("player")) {
			player.sync(data.timestamp, data.player);
		}

		if(data.hasOwnProperty("other")) {
			if(otherPlayers[data.other.id] == null) {
				otherPlayers[data.other.id] = new Player(camera, data.other);
			} else {
				otherPlayers[data.other.id].sync(data.timestamp, data.other);
			}
		}

		if(data.hasOwnProperty("remove")) {
			delete otherPlayers[data.remove];
		}
	}

	this.updateDelta = function(canvas, delta){
		this.update(canvas);
		player.update(delta);

		for(var index in otherPlayers) {
			var other = otherPlayers[index];
			other.update(delta);
		}
	};

	this.update = function(canvas) {
		var time = new Date().getTime();
		if(keyboard.isDown(Keys.Up) || keyboard.isDown(Keys.W)) {
			camera.y += camera.speed;
		}

		if(keyboard.isDown(Keys.Down) || keyboard.isDown(Keys.S)) {
			camera.y -= camera.speed;
		}

		if(keyboard.isDown(Keys.Left)|| keyboard.isDown(Keys.A)) {
			camera.x += camera.speed;
		}

		if(keyboard.isDown(Keys.Right)|| keyboard.isDown(Keys.D)) {
			camera.x -= camera.speed;
		}

		if(keyboard.isPressed(Keys.Space)) {
			camera.x = -player.position.x + (canvas.width / 2);
			camera.y = -player.position.y + (canvas.height / 2);
		}

	};

	this.draw = function(context) {

		for(var index in otherPlayers) {
			var other = otherPlayers[index];
			other.draw(context);
		}

		player.draw(context);
	};

	this.mouseMove = function(canvas, x, y) {
		//calculate angle between player and cursor
		if(!player.moveToTarget) {
			var angleRadians = Math.atan2(y - (player.position.y + camera.y), x - (player.position.x + camera.x));
			player.targetAngle = angleRadians;
		}
	};

	this.mouseClick = function(canvas, button, x, y) {
		var time = new Date().getTime();
		switch(button) {
			case 0:
			var origin = {x: player.position.x, y: player.position.y};
			var target = {x: x - camera.x, y: y - camera.y};
			this.sendMessage({"action":"target", "start": time, "origin": origin, "position": target});
			player.moveToTarget = true;
			player.targetDestination = target;
			break;
			case 1:
			
			break;
			case 2:
			
			break;
		}
	};

	this.contextMenu = function(canvas, event) {

	};

	this.disconnect = function() {
		delete player;
	}
}