function onCanvasNonPrimaryRelease( event ) {
    /**
     * Raised when any non-primary pointer button is released on the {@link OpenSeadragon.Viewer#canvas} element.
     *
     * @event canvas-nonprimary-release
     * @memberof OpenSeadragon.Viewer
     * @type {object}
     * @property {OpenSeadragon.Viewer} eventSource - A reference to the Viewer which raised this event.
     * @property {OpenSeadragon.MouseTracker} tracker - A reference to the MouseTracker which originated this event.
     * @property {OpenSeadragon.Point} position - The position of the event relative to the tracked element.
     * @property {String} pointerType - "mouse", "touch", "pen", etc.
     * @property {Number} button - Button which caused the event.
     *      -1: none, 0: primary/left, 1: aux/middle, 2: secondary/right, 3: X1/back, 4: X2/forward, 5: pen eraser.
     * @property {Number} buttons - Current buttons pressed.
     *      Combination of bit flags 0: none, 1: primary (or touch contact), 2: secondary, 4: aux (often middle), 8: X1 (often back), 16: X2 (often forward), 32: pen eraser.
     * @property {Object} originalEvent - The original DOM event.
     * @property {?Object} userData - Arbitrary subscriber-defined object.
     */
    this.raiseEvent( 'canvas-nonprimary-release', {
        tracker: event.eventSource,
        position: event.position,
        pointerType: event.pointerType,
        button: event.button,
        buttons: event.buttons,
        originalEvent: event.originalEvent
    });
}
Raised when any non-primary pointer button is pressed on the {@link OpenSeadragon.Viewer#canvas} element.

@event canvas-nonprimary-press
@memberof OpenSeadragon.Viewer
@type {object}
@property {OpenSeadragon.Viewer} eventSource - A reference to the Viewer which raised this event.
@property {OpenSeadragon.MouseTracker} tracker - A reference to the MouseTracker which originated this event.
@property {OpenSeadragon.Point} position - The position of the event relative to the tracked element.
@property {String} pointerType - "mouse", "touch", "pen", etc.
@property {Number} button - Button which caused the event.
     -1: none, 0: primary/left, 1: aux/middle, 2: secondary/right, 3: X1/back, 4: X2/forward, 5: pen eraser.
@property {Number} buttons - Current buttons pressed.
     Combination of bit flags 0: none, 1: primary (or touch contact), 2: secondary, 4: aux (often middle), 8: X1 (often back), 16: X2 (often forward), 32: pen eraser.
@property {Object} originalEvent - The original DOM event.
@property {?Object} userData - Arbitrary subscriber-defined object.