Muting a sound before it has ever been played crashes the game in Firefox 31 (and possibly previous versions and other browsers too)

[osmanzeki]

Hello,

The problem seems to occur when a dev tries to unmute a sound that has not yet been muted. In Chrome, this doesn't crash the game but it does in Firefox (possibly in other browsers without V8-like behaviour).

This is the error that you would usually get :

TypeError: Value being assigned to AudioParam.value is not a finite floating-point value.

This error occurs because the property this._muteVolume is undefined at that point as it is only dynamically created when Sound.mute = true is set beforehand.

The code that is causing this error is as follows (Sound.js :: http://docs.phaser.io/Sound.js.html#sunlight-1-line-843):

value = value || null;

if (value)
{
    this._muted = true;

    if (this.usingWebAudio)
    {
        this._muteVolume = this.gainNode.gain.value;
        this.gainNode.gain.value = 0;
    }
    else if (this.usingAudioTag && this._sound)
    {
        this._muteVolume = this._sound.volume;
        this._sound.volume = 0;
    }
}
else
{
    this._muted = false;

    if (this.usingWebAudio)
    {
        this.gainNode.gain.value = this._muteVolume;
    }
    else if (this.usingAudioTag && this._sound)
    {
        this._sound.volume = this._muteVolume;
    }
}

this.onMute.dispatch(this);

I believe a simple fix to this issue would be to add a line such as this one to the Sound classe's initial closure function (as well as any other class that uses this internal property) :

    /**
    * @property {number} _muteVolume - Internal marker var.
    * @private
    */
    this._muteVolume = 0;

If the mute property is ever set to true, the the this._muteVolume property would be overriden with this line of code :

this._muteVolume = this.gainNode.gain.value;
this.gainNode.gain.value = 0;

And if not, it would already be set to 0 instead of undefined (which seems to be what cause the crash in Firefox).

I can create a pull request for this patch, but I'd rather have some opinion about this beforehand. I will temporarily fix this issue by either muting the sound first and then unmuting or adding the suggested line of code in my local version of Sound.js.

Thank you!

[photonstorm]

Thanks for finding this out. Fixed in dev.