add start of box2d physics

package.json

@@ -14,7 +14,7 @@
   "author": "Markus Scully <markusscully@gmail.com>",
   "license": "ISC",
   "dependencies": {
-    "box2dweb": "^2.1.0-b",
+    "box2d-html5": "^0.1.230",
     "colors": "^1.1.2",
     "express": "^4.13.4",
     "recursive-readdir": "^1.3.0",

server/game/room/world/body.js

@@ -2,7 +2,9 @@
 
 class Body {
 	constructor() {
-		
+		this.b2body = false;
+		this.type = 'dynamic';
+		this.health = 1;
 	}
 }
 

server/game/room/world/fixture.js

@@ -0,0 +1,13 @@
+'use strict';
+
+const Body = require('./body.js');
+
+class Fixture extends Body {
+	constructor(player) {
+		super();
+
+		this.type = 'static';
+	}
+}
+
+module.exports = Ship;

server/game/room/world/index.js

@@ -1,10 +1,11 @@
 'use strict';
 
+const Physics = require('./physics.js');
 const Ship = require('./ship.js');
 
 class World {
 	constructor() {
-		this.box2d = false;
+		this.physics = new Physics();
 		this.bodies = new Set();
 		this.structures = new Set();
 		this.asteroids = new Set();
@@ -14,7 +15,9 @@ class World {
 
 	addPlayer(player) {
 		this.players.add(player);
-		this.ships.set(player, new Ship(player));
+		let ship = new Ship(player);
+		this.ships.set(player, ship);
+		this.physics.createBody(ship);
 	}
 
 	removePlayer(player) {

server/game/room/world/physics.js

@@ -0,0 +1,48 @@
+'use strict';
+
+// This file is very similar, but not identical to its client counterpart
+// so most changes done to it should be mirrored there to keep consistent
+// physics between client and server.
+
+const Box2D = require('box2d-html5');
+
+const b2Vec2 = Box2D.b2Vec2;
+
+class Physics {
+	constructor() {
+		this.world = new Box2D.b2World(new b2Vec2(0, 0), false);
+	}
+
+	createBody(body) {
+		let bodyDef = new Box2D.b2BodyDef();
+		bodyDef.userData = body;
+		bodyDef.position = new b2Vec2(body.x || 0, body.y || 0);
+		bodyDef.fixedRotation = false;
+		bodyDef.active = true;
+		bodyDef.linearVelocity = new b2Vec2(body.xvel || 0, body.yvel || 0);
+		bodyDef.angularVelocity = body.rvel || 0;
+		bodyDef.type = body.type == 'static' ?
+			Box2D.b2Body.b2_staticBody : Box2D.b2Body.b2_dynamicBody;
+		let b2body = this.world.CreateBody(bodyDef);
+
+		let fixtureDef = new Box2D.b2FixtureDef();
+		fixtureDef.density = 10;
+		fixtureDef.friction = 1;
+		fixtureDef.restitution = 0;
+
+		for (var poly of body.structure) {
+			poly.map(vertex => new b2Vec2(vertex[0], vertex[1]));
+			fixtureDef.shape = new Box2D.b2PolygonShape();
+			fixtureDef.shape.SetAsArray(poly, poly.length);
+			b2body.CreateFixture(fixtureDef);
+		}
+
+		body.b2body = b2body;
+	}
+
+	step() {
+		this.world.Step(1, 5, 1 / 60);
+	}
+}
+
+module.exports = Physics;

server/game/room/world/ship.js

@@ -1,12 +1,17 @@
 'use strict';
 
+const defaults = require('./traits/defaults.json');
+const hulls = require('./traits/hulls.json');
+
 const Body = require('./body.js');
 
 class Ship extends Body {
-	constructor(player) {
+	constructor(player, build) {
 		super();
 
+		this.build = build || defaults.spawnShip.build;
 		this.player = player;
+		this.structure = hulls[this.build.hull];
 	}
 }
 

server/game/room/world/traits/defaults.json

@@ -0,0 +1,8 @@
+{
+	"spawnShip": {
+		"build": {
+			"hull": "01",
+			"turrets": [0]
+		}
+	}
+}

server/game/room/world/traits/hulls.json

@@ -0,0 +1,12 @@
+{
+	"01": [
+		[
+			[1, 28],
+			[30, 28],
+			[30, 19],
+			[18, 2],
+			[13, 2],
+			[1, 19]
+		]
+	]
+}