• Open Menu Close Menu
  • Apple
  • Shopping Bag
  • Apple
  • Mac
  • iPad
  • iPhone
  • Watch
  • TV
  • Music
  • Support
  • Search apple.com
  • Shopping Bag

Lists

Open Menu Close Menu
  • Terms and Conditions
  • Lists hosted on this site
  • Email the Postmaster
  • Tips for posting to public mailing lists
Re: AU automation gestures/scroll wheel events
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: AU automation gestures/scroll wheel events


  • Subject: Re: AU automation gestures/scroll wheel events
  • From: Howard Moon <email@hidden>
  • Date: Mon, 15 Jun 2009 14:16:55 -0700

Ok, but that doesn't answer the question about how to handle scroll wheel changes that DO cause parameter value changes. Should begin/ end gestures be sent? If so, is there a preferred way to go about it?

-Howard


On Jun 11, 2009, at 2:47 PM, William Stewart wrote:

we don't send begin/end gestures if the change is not a gesture that would begin a potential series of parameter changes.

For example, when you directly edit the value of the parameter in a text box, then we just set the new value - no gesture

Bill

On Jun 7, 2009, at 3:43 PM, Brian Willoughby wrote:


On Jun 5, 2009, at 20:31, Jim Wintermyre wrote:
ii) Using the mouse scroll wheel for GUI elements poses the problem of when to send begin and end gestures. I'm thinking the best way would be to simply measure elapsed time between events and send an end gesture if elapsed time is greater than a timeout value. Anyone got any better ideas?

Yeah, that's a tough one. We have the same problem. We let the user move the mouse over a knob and then move it by adjusting the scroll wheel. But sending the begin/end gestures on each scroll wheel movement notification (several per typical "scroll") breaks in touch automation mode. The timer thought might be the best workaround, just cancel it immediately if some other param change starts before the timeout is reached. Yes, this will break if the user actually intended to leave the last value "pressed" for a while, but you simply can't do that with a non-pressable scroll wheel. Typically users only want the scroll wheel for quick adjustments of knobs anyway, as a shortcut to having to click and drag. For something where they want to leave it at a certain value for a while, they just have to click and drag.


That mostly seems reasonable, but I'm left with the question: Why fake a gesture at all? When developing any software which responds to gestures, I would not want to see certain changes grouped into a gesture unless it was absolutely certain that they were indeed a gesture that comes from human interaction.

Does Apple have anything to say about this? Is there any recommendation for whether gesture begin and end messages should be sent? It seems like there are three ways to handle this: A) Send no gesture messages at all when the HID cannot sense gestures - only the value change messages would be sent. B) Send begin and end gesture messages around each individual value change, thus making it clear that no two value changes can reliably be assumed to be part of the same gesture. C) Use a timer to estimate gestures, without any certainty, and place begin and end around groups. It's the latter of the three that I find to be the least correct option, but that is just my opinion at the moment. I'd like to hear more discussion of this, particularly from Apple.

I've read the AudioUnit documentation, and skimmed the "ink gesture" documentation, and I see nothing which condones "inventing" gesture begin/end marks when they're not conclusive. The message is intended to expand the API beyond mere mouse down and mouse up, but I do not believe that it is intended that everyone insert these messages based upon guesswork.

Brian Willoughby
Sound Consulting

_______________________________________________
Do not post admin requests to the list. They will be ignored.
Coreaudio-api mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
40apple.com


This email sent to email@hidden

_______________________________________________
Do not post admin requests to the list. They will be ignored.
Coreaudio-api mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
40antarestech.com


This email sent to email@hidden

_______________________________________________ Do not post admin requests to the list. They will be ignored. Coreaudio-api mailing list (email@hidden) Help/Unsubscribe/Update your Subscription: This email sent to email@hidden
  • Follow-Ups:
    • Re: AU automation gestures/scroll wheel events
      • From: Brian Willoughby <email@hidden>
References: 
 >Re: AU automation gestures/scroll wheel events (From: Jim Wintermyre <email@hidden>)
 >Re: AU automation gestures/scroll wheel events (From: Brian Willoughby <email@hidden>)
 >Re: AU automation gestures/scroll wheel events (From: William Stewart <email@hidden>)

  • Prev by Date: Re: Audio Units and virtual device implementation
  • Next by Date: Re: AU automation gestures/scroll wheel events
  • Previous by thread: Re: AU automation gestures/scroll wheel events
  • Next by thread: Re: AU automation gestures/scroll wheel events
  • Index(es):
    • Date
    • Thread