VK AudioVolume

vk_audioVolume={
   step:10, // default step for inc & dec functions
   inc:function(val){
      var player = window.audioPlayer.player;
      var step=val?val:vk_audioVolume.step;
      var vol=player.getVolume()*100;
      player.setVolume(Math.min(vol+step,100)/100);
      vk_audioVolume.upd_view();
   },
   dec:function(val){
      var player = window.audioPlayer.player;
      var step=val?val:vk_audioVolume.step;
      var vol=player.getVolume()*100;
      player.setVolume(Math.max(vol-step,0)/100);
      vk_audioVolume.upd_view();
   },
   set:function(vol){
      var player = window.audioPlayer.player;
      vol=vol>100?100:(vol<0?0:vol);
      player.setVolume(vol/100);
      vk_audioVolume.upd_view();
   },
   upd_view:function(){
      var ge=window.ge;
      var _a=window.audioPlayer;
      var el=ge('audio_vol'+_a.id);
      var vol=Math.round(_a.volW*_a.player.getVolume());
      if (ge('audio_volume_line'+_a.id))
            ge('audio_vol_slider'+_a.id).style.left=vol+'px';
      if (ge('gp_vol_slider'))
            ge('gp_vol_slider').style.left=vol+'px';
   }
}

// USE EXAMPLES

vk_audioVolume.inc();   // INCREASE VOLUME
vk_audioVolume.dec();   // DECREASE
vk_audioVolume.dec(10); // VOLUME - 10%
vk_audioVolume.inc(20); // VOLUME + 20%
vk_audioVolume.set(0);  // 0% VOLUME
vk_audioVolume.set(50); // 50% VOLUME