/*

    Copyright (C) 2016 Apple Inc. All Rights Reserved.

    See LICENSE.txt for this sample’s licensing information

    Abstract:

    View controller for the Master tab. Example of how to manually perform haptic feedback.

*/

import Cocoa

class MasterViewController: NSViewController {

    @IBOutlet weak var rotatableImage: NSImageView!

    @IBAction func sliderValueChanged(_ sender: NSSlider) {

        let rotationValue = CGFloat(sender.integerValue)

        rotatableImage.frameCenterRotation = rotationValue

        guard rotationValue == 0 else { return }

        /*

            Use the `NSHapticFeedbackManager` class to perform alignment haptic

            feedback on the Force Touch trackpad.

            Note: You can call this even if this Macintosh doesn't have a Force

            Touch Trackpad Haptic feedback should be used sparingly. Here we are

            performing it when the user aligns the photo to 0 degrees. A more

            real world example would be when the user aligns the photo to when 

            the horizon is level.

            Ideally, the velocity of slider value changes would be considered such

            that haptic feedback is only performed when the user is trying to find

            the alignment point (aka moving slowly). This is left as an exercise

            for the reader.

        */

        NSHapticFeedbackManager.defaultPerformer().perform(.alignment, performanceTime: .default)

    }

}