code: function( world ){
  
              if ( this.disconnect && this._world ){
                  this.disconnect( this._world );
              }
  
              this._world = world;
  
              if ( this.connect && world ){
                  this.connect( world );
              }
  
              return this;
          }
docs: Renderer#setWorld( world ) -> this
  - world (Object): The world (or null)
  
  Set which world to apply to.
  
  Usually this is called internally. Shouldn't be a need to call this yourself usually.