More function documentation

src/playsound.c

@@ -33,6 +33,20 @@ int mute;
 int use_sound = 1;
 static int old_sound[4] = { -1, -1, -1, -1 };
 
+/**
+ * Play a sound.
+ *
+ * @param screen Screen surface (for dealing with panning & volume)
+ * @param chan Channel to play on (-1 for first free unused channel)
+ * @param s Which sound to play (integer index of `sounds[]` array)
+ * @param override 1 to override an already-playing sound, 0 otherwise
+ * @param x X coordinate within the screen surface, for left/right panning
+ *   effect; or SNDPOS_LEFT, SNDPOS_CENTER, or SNDPOS_RIGHT for
+ *   far left, center, or far right panning, respectively.
+ * @param y Y coordinate within the screen surface, for volume control
+ *   (low values, near the top of the window, are quieter), or
+ *   SNDDIST_NEAR for full volume
+ */
 void playsound(SDL_Surface * screen, int chan, int s, int override, int x, int y)
 {
 #ifndef NOSOUND