Continue playing even if the browser tab is not in focus about webaudiofont

[surikov]

Browser manufacturers force background pages to reduce resource consumption.
This is the rule for all browsers.
I don't want to fight browser makers.

[alfedukovich]

Use setTimeout or setInterval to queue ahead until the queue finishes playing. Then playback won't stop when you switch tabs.
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[page200]

Thank you, that example indeed works and uses setInterval, and the variant with setTimeout works as well. setInterval or setTimeout seem nice for auto-repeating the song for an unlimited number of times.

On the other hand, for each playthrough of a song, I wonder whether anything speaks against simply setting stepDuration to the song duration, i.e. queueing the entire song via queueWaveTable() at once. The notes are then scheduled here via the start() method of an AudioBufferSourceNode, so the browser makers decide what to do with that, and we're not fighting them. (For now. :))

[page200]

Setting a long stepDuration works in Firefox and for some MIDI files in Chrome. For other MIDI files in Chrome, the audio stops after a second. Maybe Chrome is stupid in that it focuses on computing something too early for future sounds instead of playing imminent sounds as intended (like Firefox does).

Instead of a long stepDuration, what seems to work is to call each step with window.setTimeout instead of window.requestAnimationFrame. Both are unnecessarily resource-intensive except if setTimeout takes into account when the next note will actually play instead of getting called every 10 milliseconds.