. added SetMusicVolume script function.

src/sound/i_music.cpp

@@ -680,6 +680,14 @@ void I_SetMusicVolume (float factor)
 	snd_musicvolume.Callback();
 }
 
+DEFINE_ACTION_FUNCTION(DObject, SetMusicVolume)
+{
+	PARAM_PROLOGUE;
+	PARAM_FLOAT(vol);
+	I_SetMusicVolume((float)vol);
+	return 0;
+}
+
 //==========================================================================
 //
 // test a relative music volume

wadsrc/static/zscript/base.txt

@@ -12,6 +12,7 @@ class Object native
 	native static bool S_ChangeMusic(String music_name, int order = 0, bool looping = true, bool force = false);
 	native static void C_MidPrint(string fontname, string textlabel, bool bold = false);	// always uses the stringtable.
 	native static uint BAM(double angle);
+	native static void SetMusicVolume(float vol);
 
 	native Name GetClassName();