描述

With this function you can get the absolute value for the global volume of all sounds and music for a specific listener. The default listener index is 0, but you can use the function audio_get_listener_info to get the different indices available for the target platform. The gain value returned is based on a linear scale from 0 (silent) to 1 (full volume). Note that on some platforms you can have a gain of greater than 1, although a value of 1 is considered "full volume" and anything greater may introduce audio clipping.

语法：

audio_get_master_gain(listenerIndex);

返回：

Real（实数）

例如：

var num = audio_get_listener_count();
for( var i = 0; i < num; ++i;)
   {
   var info = audio_get_listener_info(i);
   var ind = info[?"index"];
   if audio_get_master_gain(ind) != 1
      {
      audio_set_master_gain(info[?"index"], 1);
      }
   ds_map_destroy(info);
   }

The above code loops through the available listeners, checking to see if their gain is 1 or not, and if it is not it sets it to 1 for each of them.