code: function(){
  
              if ( !this._renderer ){
                  throw "No renderer added to world";
              }
  
              this._renderer.render( this._bodies, this._meta );
              this.emit('render', {
                  bodies: this._bodies,
                  meta: this._meta,
                  renderer: this._renderer
              });
              return this;
          }
docs: chainable
  Physics.world#render() -> this
  
  Render current world state using the renderer