How to mute / unmute BASS?

Question

How can i mute and unmute BASS playback (platform independend)? Until now i save the current volume before muting, set volume to 0 and set it back if unmute.

Example:
_{part of my C++ class}

volume_t lastVolume; // 0.0f = silent, 1.0f = max (volume_t = float)

// ...

bool mute(bool mute)
{
    if( mute )
    {
        lastVolume = getVolume(); // Save current volume

        return setVolume(0.0f); // Set volume to silent
    }
    else
    {
        return setVolume(lastVolume); // restore last volume before muting
    }
}

Is there a better way to do this? In the BASS Api documentation there's only one mute function:

BOOL BASS_WASAPI_SetMute(
    BOOL mute
);

However, this looks good, but unfortunately its part of BASSWASAPI (WASAPI I/O on Windows Vista and later - which is not crossplatform).

Answer 1

Here's my solution:

class PlayerBASS : public virtual AbstractPlayer
{
public:

    // ...

    /**
     * Set volume on current channel.
     * 
     * @param volume      volume (0.0f - 1.0f)
     */
    bool setVolume(volume_t volume)
    {
        return BASS_ChannelSetAttribute(streamHandle, BASS_ATTRIB_VOL, volume);
    }

    /**
     * Get volume on current channel.
     *
     * @return            volume (0.0f - 1.0f)
     */
    volume_t getVolume()
    {
        float value;
        BASS_ChannelGetAttribute(streamHandle, BASS_ATTRIB_VOL, &value);

        return value;
    }

    /**
     * Mute / Unmute the volume on current channel.
     *
     * @return            'true' if successful, 'false' if error
     */
    bool mute(bool mute)
    {    
        if( mute == muted ) // dont mute if already muted (and vice versa)
            return true;

        bool rtn; // returnvalue

        if( mute ) // mute
        {
            lastVolume = getVolume(); // save current volume
            rtn = setVolume(0.0f); // set volume to 0.0f (= mute)
            muted = true; // set mute-state
        }
        else // unmute
        {
            rtn = setVolume(lastVolume); // restore volume
            muted = false; // set mute-state
        }

        return rtn; // returnvalue
    }

    // ...

private:
    // ...
    HSTREAM streamHandle; // Streamhandle
    bool muted; // flag for mute-state ('true': muted, 'false': unmuted) - init with 'false'
    volume_t lastVolume; // lastVolume
};

Don't use BASS_SetVolume() / BASS_GetVolume() here - it will set volume of your whole system!

Thats it!