SoundChannels

moopf

Just a quick question on SoundChannels. I don't see any built in way to check if a SoundChannel is still playing, so are SoundChannels just destroyed once they've finished playing whatever it is they're playing?

Mells

Checking if a sound channel is playing

On feb 29

local channel = sound:play() if channel ~= nil then channel:addEventListener(Event.COMPLETE, function(channel) channel.complete = true end, channel) end

Note : It's recommended to do a nil check on the returned SoundChannel object.

I hope it helps.

petec

I use this format to stop channels as I exit a scene and it seems to work:

local channel=sound:play() if channel then channel:stop() end

so I guess that channel not being nil means it is playing?

moopf

OK, thanks for the replies. One other question, is there a way to pause a SoundChannel?

Mells

By reading this answer, it seems that @ar2rsawseen would know the solution :

(...) you can create one Sound, and play it multiple times (creating new channel every time) and manipulate them (pause, volume, etc) separately.

OZApps

Pause (toggling) would be similar to
Seek current position and store it somewhere
Stop the playback
Play/resume playback from the seek point

moopf

Hi @Mells - that's interesting as there's nothing in the api documentation about pausing. You can certainly get and set the sound volume on a channel. The only way I can think of doing it is to use SoundChannel:getPosition() then stop and destroy the channel when you pause, then on resume trigger the sound to play again but specify the start sound in Sound:play(startTime,loops).

I'll be honest, the audio API as it stands really does seem to be lacking. I know it's on one of the roadmap lists to improve it and I can't wait to see what @atilim does because currently it's bare-bones at best.

I'm having to write an audio manager just to try and facilitate some pretty basic functionality, with a hodge-podge of the limited facilities we have currently.

moopf

Pause (toggling) would be similar to
Seek current position and store it somewhere
Stop the playback
Play/resume playback from the seek point

Yes, that's the only way I can think of doing it (see above which I was writing as you replied).

Mells

@moopf
I came to the same conclusion as yours.
What you suggested, also mentioned by @OZApps, is the only way that I know of.
That's why I am intrigued to know if Arturs knows a better way.

ar2rsawseen

@Mells, no, don't know better way, but actually thats a great idea to implement into GiderosCodingEasy. I'll need to experiment more on what happens to SoundChannel

moopf

Right well I kind of have the basics of my audio manager done. I've implemented music fading (using GTween to tween volume after a creating a setter and getter - @ar2rsawseen I think I originally saw that from you, thanks) so when a new track is provided the current one is faded out.

But, even when it's faded out there's audio glitches when the track changes - sometimes it's just a click, sometimes it's actually the previous music playing briefly for half a second or so before going to the next track. This is on an iPhone 4S.

Basically something seems a little broken.

moopf

Well I've kind of limited the issue by introducing a "fake" tween at the end of the volume fade tween that gives a 1 second gap between stopping the channel that the music is playing on and starting a new one playing. I guess things just need to catch up in the background. Although it still occasionally plays the last track at full volume for a split second before starting the track it should be. That, again, seems like an mp3 buffer still being full somewhere - whether that's Gideros or iOS I don't know. Will try on Android later and cry

moopf

More clicks and weirdness reduced by introducing a 0.2 second volume tween from 0 to required volume when a track is played. Still not perfect though.

One question, internally in Gideros does it use hardware decoding where available (on iOS for instance) for background music?

Mells

@moopf

Well I've kind of limited the issue by introducing a "fake" tween at the end of the volume fade tween that gives a 1 second gap between stopping the channel that the music is playing on and starting a new one playing.

Just wondering, why don't you use a delay (in seconds, not ms) to achieve that?

local tween2 = GTween.new(sprite, 1, {}, {autoPlay = false, delay = 1}) local tween1 = GTween.new(sprite, 1, {}, {nextTween = tween2})

moopf

Hi @Mells - I'm just trying rough code at the moment to locate the issue - you're right, that can also be done how you suggest. But I think @atilim needs to weigh in on this when he's back of holidays.

moopf

Hi @atilim, now you're back working again when you get a moment could you comment on the issues in this thread please? Pretty please