code: function(visible) {
              Kinetic.Node.prototype.setVisible.call(this, visible);
              if(visible) {
                  this.getCanvas()._canvas.style.display = 'block';
              }
              else {
                  this.getCanvas()._canvas.style.display = 'none';
              }
              return this;
          }
docs: extend Node.prototype.setVisible