add boilerplate for mounts and fixtures

server/game/room/world/body/turret/fixture.js

@@ -0,0 +1,34 @@
+'use strict';
+
+const traits = require('../../traits/turrets.json');
+
+class Fixture {
+	constructor(hardpoint, data) {
+		this.hardpoint = hardpoint;
+
+		this.projectiles = new WeakSet();
+
+		let turretTraits = traits[data.type];
+
+		this.rof = turretTraits.rateOfFire;
+
+		this.traversal = this.hardpoint.traversal || false;
+		this._angle = this.traversal ? this.traversal.cw : 0;
+	}
+
+	destruct() {
+		this.projectiles.forEach(p => p.world.removeBody(p));
+	}
+
+	get angle() {
+		return this._angle;
+	}
+
+	set angle(angle) {
+		// TODO: Check if within traversal limit if on mount.
+		if (this.type == 'fixed') return;
+		this._angle = angle;
+	}
+}
+
+module.exports = Fixture;