Sound for sliders

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This sim has the following sliders:

• Discrete: custom amplitude sliders
• Discrete: standard volume slider for Fourier series sound
• Wave Pack: 4 standard sliders in the control panel

From #54

Amplitude sliders would probably not have a "harmonic" sound, probably just click, click, click (like Waves Intro).

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Waves Intro adds sounds in WaveInterferenceSlider.js:

import generalBoundaryBoopSoundPlayer from '../../../../tambo/js/shared-sound-players/generalBoundaryBoopSoundPlayer.js';
import generalSoftClickSoundPlayer from '../../../../tambo/js/shared-sound-players/generalSoftClickSoundPlayer.js';

Playing these sounds must be handled in the Slider's options.drag function.

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Below is the code that plays sounds in WaveInterferenceSlider.js.

@jbphet @samreid is this really the recommended pattern? Is this the level of support that's available for Slider sound? And PDOM events have to be handled separately? And the client is responsible for checking elapsed time between sounds?!?

      drag: event => {

        const value = property.value;

        if ( event.isFromPDOM() ) {

          if ( Math.abs( value - property.range.max ) <= TOLERANCE ||
               Math.abs( value - property.range.min ) <= TOLERANCE ) {
            generalBoundaryBoopSoundPlayer.play();
          }
          else {
            generalSoftClickSoundPlayer.play();
          }
        }
        else {

          // handle the sound as desired for mouse/touch style input
          for ( let i = 0; i < ticks.length; i++ ) {
            const tick = ticks[ i ];
            if ( lastValue !== value && ( value === property.range.min || value === property.range.max ) ) {
              generalBoundaryBoopSoundPlayer.play();
              break;
            }
            else if ( lastValue < tick.value && value >= tick.value || lastValue > tick.value && value <= tick.value ) {
              if ( phet.joist.elapsedTime - timeOfLastClick >= MIN_INTER_CLICK_TIME ) {
                generalSoftClickSoundPlayer.play();
                timeOfLastClick = phet.joist.elapsedTime;
              }
              break;
            }
          }
        }

[samreid]

That pattern was recommended when we worked on it in mid-2020. @jbphet is there better common code support for this now? Should there be?

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From 4/22/21 design meeting

There is currently no sound API for Slider, because most sounds were pedagogical.

Now that some sims have been instrumented, there are probably some common patterns for sound in Sliders. @jbphet will identify those in phetsims/sun#697 and develop a sound API for Slider, including some type of default non-pedagogical sound, like WaveInterfaceSlider.

In the meantime, I've added rudimentary sound to the amplitude sliders in Fourier. I did that totally in AudibleSlider, a Slider subclass. It's a bit like the approach used in WaveInterfaceSlider, and I'm hoping that AudibleSlider can be entirely deleted once phetsims/sun#697 is completed.

Work on this is on hold until the Slider sound API is ready.

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Common-code work for Slider sound is being done by @jbphet in phetsims/sun#697.

Fourier currently has a sim-specific implementation of Slider sound for Amplitude sliders, with behavior identical to Waves Intro. As the thumb is moved (with mouse, touch, or keyboard), there are discrete "tick" sounds. At the min/max there is a specific sound. And there is no sound when the value is changed by clicking on the track (a deficiency in the Waves Intro implementation, not easily correct in Fourier). You can test-drive this is master or any recent dev version.

To help prioritize our work, it would be helpful to know whether the sim-specific implementation is sufficient for Fourer 1.0, or whether the common-code work needs to be completed (and is therefore blocking).

@arouinfar @kathy-phet your thoughts?

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Raising priority to get feedback from @arouinfar and @kathy-phet. Please re-read the previous comment. Slider sound API is a large task, so if this is needed, that work needs to start very soon.

[arouinfar]

A sim-specific approach seems reasonable to me. Perhaps we can defer the common code work until we get to a 3rd sim that wants to use the slider clicks. I know it's unconventional to wait so long to generalize, but given current priorities, it seems okay. I can't make that call, however, so leaving it up to @kathy-phet.

[kathy-phet]

Sim-specific is OK, so this shouldn't be blocking for this sim publication. But I will add as a line item in PhET overview, to keep it on the radar for a future quarterly goal.

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@jbphet recently added sound support for Slider. But in fa33958 for phetsims/sun#697, he disabled that support in AmplitudeSlider.js:

soundGenerator: ValueChangeSoundGenerator.NO_SOUND,

What really needs to be done is to delete the ad hoc sound from AmplitudeSlider.js (SoundDragHandler) and enable the Slider sound.

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In the above commit, I replaced ad hoc sound (SoundDragHandler) with Slider sound support. A sound in now generated on each value change, in 0.05 interval. This results a LOT of sound when dragging the slider, kind of like an angry bumble bee. So we'll need to discuss what (in general) should we do when there are a lot of value changes? Is it OK to have no sound for some values? I guess this would have to be the case if we're going to use discrete sounds for contiuous sliders.

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Now that Sliders have sound by default, all Sliders (and NumberControls) in this sim will need to be reviewed.

In particular, I think that it makes sense to turn sound off for the slider that controls the output level of the Fourier Series (see screenshot below). Since this slider is itself controlling sound, it's distracting/confusing to have it make sound. @arouinfar do you agree?

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@arouinfar agrees that the slider that controls the output level of the Fourier Series should not have sound enabled.

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Labeling as blocks-sim-publication because all sliders need to be reviewed before publishing from master again.

Self unassigning until we work on this sim again.

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phetsims/sun#697 was completed, so Sliders in this sim now have sound. This needs to be reviewed when work on this sim resumes. It's on-hold and unassigned until then.

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Ready for testing in phetsims/qa#1178. You may close this issue if it looks OK.

This issue is relevant to the 4 horizontal sliders that appear in the Wave Packet screen:

This issue is not relevant to the sound slider that appears in the Discrete screen. That slider has no sound by design, because (when the checkbox next to it is checked) it controls the volume of a sound.

[Nancy-Salpepi]

Sliders sound good to me.
Closing!