What physical attribute of the vibration is the haptic sharpness?

Hey!


I'm doing some research on the haptic feedback with some Apple devices, and I'm wondering what the haptic sharpness (https://developer.apple.com/documentation/corehaptics/chhapticevent/parameterid/3114596-hapticsharpness) physically map to?

While I understand that the intensity (https://developer.apple.com/documentation/corehaptics/chhapticevent/parameterid/3114595-hapticintensity) maps to amplitude of the vibration, the physical attribute of the sharpness is not directly stated in the documentation. I'm wondering if it's the frequency of the vibration or is it waveform ( see examples of waveform here: https://www.precisionmicrodrives.com/haptic-feedback/haptic-evaluation-kit-tutorial-building-your-own-vibration-alerts/ )


Thank you very much & have a nice day!

Kevin

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KevinHanAU
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I have no idea what the diagram in that hapticSharpness link means, but from what I remember of the WWDC video, sharpness represents the rapidity of the transition between onset and decay. You can get an idea from the graphic in the video here:


https://developer.apple.com/videos/play/wwdc2019/223/?time=359

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QuinceyMorris
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The reason we don't give specifics about the physical mapping of Sharpness is that the parameters exposed via the CoreHaptics API are abstracted to represent a range of *experience*, not a particular set of waveform characteristics. Even HapticIntensity could be remapped at some future point (or some future hardware) to generate a range of *experienced* intensities via something other than amplitude.

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SoundOfMind
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