Recent Chrome changes to sound autoplay settings

[kripken]

Chrome now blocks audio from automatically playing. We are seeing reports of games and art being broken or audioless because of this.

To mitigate it, perhaps we should

• Document it in the FAQ?
• Try to connect user input to the audio device? See e.g. No sound in chrome - due to Autoplay policy changes emscripten-ports/SDL2#57

[kripken]

A good summary of the problems people are encountering: https://twitter.com/mcclure111/status/993627449991688193

[Kaosumaru]

I guess, generic polyfill for AudioContext on chrome could be added, making them 'auto-resumable' when user interacts with website. Not sure why chrome devs don't choose this to be default behavior, would be more backward compatible.

[kripken]

@Kaosumaru yeah, we might want that. Not sure yet though what the best polyfill is. Here is one option:

https://gist.github.com/surma/301c9c377aaf90a3fdae615d4840bb2e

[ruby0x1]

It's worth noting that this change is unacceptable on chrome's behalf, so while a polyfill is helpful, everyone who cares about the web platform should be making their voice heard to chrome as well.

[Beuc]

Any news on getting the audio to work with Chrome's autoplay policy? :)

[Beuc]

For the record my current all-JavaScript work-around:

      // Work-around chromium autoplay policy
      // https://github.com/emscripten-core/emscripten/issues/6511
      function resumeAudio(e) {
	  if (typeof Module === 'undefined'
	      || typeof Module.SDL2 == 'undefined'
	      || typeof Module.SDL2.audioContext == 'undefined')
	      return;
	  if (Module.SDL2.audioContext.state == 'suspended') {
	      Module.SDL2.audioContext.resume();
	  }
	  if (Module.SDL2.audioContext.state == 'running') {
	      document.getElementById('canvas').removeEventListener('click', resumeAudio);
	      document.removeEventListener('keydown', resumeAudio);
	  }
      }
      document.getElementById('canvas').addEventListener('click', resumeAudio);
      document.addEventListener('keydown', resumeAudio);

[kripken]

@Beuc Is there a good place in our default HTML to add that?

[Beuc]

I put it right after the <canvas> tag in shell.html.
However this is somewhat specific to SDL2.

[kripken]

I wonder if we shouldn't add it in the SDL2 port, then. Worth opening a PR or at least an issue to discuss that there.

It would also be good to add more details on this to our docs, like say in the FAQ.