refactor: physics restructuring

packages/physics/dummy/body.js

@@ -0,0 +1,39 @@
+import * as I from 'immutable';
+
+import {compose} from '@avocado/core';
+import {Rectangle, Vector} from '@avocado/math';
+import {EventEmitter} from '@avocado/mixins';
+
+const decorate = compose(
+  EventEmitter,
+  Vector.Mixin('position', 'x', 'y', {
+    default: [0, 0],
+    track: true,
+  }),
+);
+
+class BodyBase {
+
+  constructor(shape) {
+    this.force = [0, 0];
+    this.impulse = [0, 0];
+    this.contacts = I.Set();
+    this.shape = shape;
+  }
+
+  get aabb() {
+    return Rectangle.translated(this.shape.aabb, this.position);
+  }
+
+  applyForce(vector) {
+    this.force = Vector.add(this.force, vector);
+  }
+
+  applyImpulse(vector) {
+    this.impulse = Vector.add(this.impulse, vector);
+  }
+
+}
+
+export class Body extends decorate(BodyBase) {}
+

packages/physics/dummy/world.js

@@ -1,41 +1,9 @@
 import * as I from 'immutable';
 
-import {arrayUnique, compose} from '@avocado/core';
+import {arrayUnique} from '@avocado/core';
 import {Rectangle, QuadTree, Vector} from '@avocado/math';
-import {EventEmitter} from '@avocado/mixins';
 
-const decorate = compose(
-  EventEmitter,
-  Vector.Mixin('position', 'x', 'y', {
-    default: [0, 0],
-    track: true,
-  }),
-);
-
-class BodyBase {
-
-  constructor(shape) {
-    this.force = [0, 0];
-    this.impulse = [0, 0];
-    this.contacts = I.Set();
-    this.shape = shape;
-  }
-
-  get aabb() {
-    return Rectangle.translated(this.shape.aabb, this.position);
-  }
-
-  applyForce(vector) {
-    this.force = Vector.add(this.force, vector);
-  }
-
-  applyImpulse(vector) {
-    this.impulse = Vector.add(this.impulse, vector);
-  }
-
-}
-
-export class Body extends decorate(BodyBase) {}
+import {Body} from './body';
 
 export class World {