Fading Sounds

bowerandy

Folks,

As far as I'm aware there isn't a built-in way of fading sounds in Gideros. So, following my often quipped mantra that one can Tween Anything, here are some simple additions to SoundChannel to allow you to fade sounds in and out.

SoundChannel.___set=SoundChannel.set   function SoundChannel:set(param, value) if param=="volume" then self:setVolume(value) elseif param=="pitch" then self:setPitch(value) else SoundChannel.___set(self, param, value) end return self end   SoundChannel.___get=SoundChannel.get   function SoundChannel:get(param, value) if param=="volume" then return self:getVolume() end if param=="pitch" then return self:getPitch() end return SoundChannel.___get(self, param, value) end   function SoundChannel:fadeIn(duration, optFinalLevel, completionFunc) self:setVolume(0) GTween.new(self, duration, { volume=optFinalLevel or 1 }, { onComplete=completionFunc }) end   function SoundChannel:fadeOut(duration, optFinalLevel, completionFunc) GTween.new(self, duration, { volume=optFinalLevel or 0 }, { onComplete= function() self:stop() if completionFunc then completionFunc() end end }) end

So, with these methods in place you can do stuff like this:

local music=Sound.new("MyMusic.mp3") local channel=music:play() channel:fadeIn(3, 1, function() print("fade in complete") end) -- -- Later -- channel:fadeOut(3)

Note that SoundChannel:fadeOut() can also take the same additional parameters as fadeIn(), I'm just showing that you can default these if you wish. Oh, and you can also tween the pitch of (non-music) sounds too. I haven't tried it but it might be interesting to play with.

You can either use the code above, or take my BhHelpers library from GitHub.

best regards

gingerbreadkids

Nice I didn't realize GTween worked on any property. Shows how useful as a generic tweening engine - you could use the various "easing" functions or create your own to simulate echos, re-verb etc

ar2rsawseen

looks awesome, mind if I borrow for GiderosCodingEasy?

bowerandy

@ar2rsawseen, yes please include it.

In retrospect, I think that it would be more symmetrical if fadeOut() didn't call stop() and left this up to the caller if it is required. That would make fadeOut() simply:

function SoundChannel:fadeOut(duration, optFinalLevel, completionFunc) GTween.new(self, duration, { volume=optFinalLevel or 0 }, { onComplete=completionFunc }) end

best regards

gmarinov

Great!
I like a FadeOut(duration [, and_stop]) better.

FadeTo(volume,duration) functionality is about 2-3 functions or so even without GTween. Beats me why it is not native to Gideros ("you can write it yourself" doesn't count).