code: function(degrees) {
          if (!this.viewer || !this.viewer.drawer.canRotate()) {
              return this;
          }
          this.degrees = $.positiveModulo(degrees, 360);
          this._setContentBounds(
              this.viewer.world.getHomeBounds(),
              this.viewer.world.getContentFactor());
          this.viewer.forceRedraw();
  
          /**
           * Raised when rotation has been changed.
           *
           * @event rotate
           * @memberof OpenSeadragon.Viewer
           * @type {object}
           * @property {OpenSeadragon.Viewer} eventSource - A reference to the Viewer which raised the event.
           * @property {Number} degrees - The number of degrees the rotation was set to.
           * @property {?Object} userData - Arbitrary subscriber-defined object.
           */
          this.viewer.raiseEvent('rotate', {"degrees": degrees});
          return this;
      }
docs: Rotates this viewport to the angle specified.
  @function
  @return {OpenSeadragon.Viewport} Chainable.