Fix sound handling in demo freecam

- Object sounds are audible from the location of the
  camera
- Certain HUD sounds should no longer be audible
  - For instance, lap complete sfx

src/g_demo.c

@@ -3993,7 +3993,6 @@ void G_StopDemo(void)
 	demo.freecam = false;
 	// reset democam shit too:
 	democam.cam = NULL;
-	democam.soundmobj = NULL;
 	democam.localangle = 0;
 	democam.localaiming = 0;
 	democam.keyboardlook = false;

src/p_local.h

@@ -137,7 +137,6 @@ struct camera_t
 struct demofreecam_s {
 
 	camera_t *cam;	// this is useful when the game is paused, notably
-	mobj_t *soundmobj;	// mobj to play sound from, used in s_sound
 
 	angle_t localangle;	// keeps track of the cam angle for cmds
 	angle_t localaiming;	// ditto with aiming

src/p_user.c

@@ -1137,6 +1137,15 @@ boolean P_IsDisplayPlayer(player_t *player)
 		return false;
 	}
 
+	// Freecam still techically has a player in
+	// displayplayers. But since the camera is detached, it
+	// would be weird if sounds were heard from that player's
+	// perspective.
+	if (demo.freecam)
+	{
+		return false;
+	}
+
 	for (i = 0; i <= r_splitscreen; i++) // DON'T skip P1
 	{
 		if (player == &players[displayplayers[i]])
@@ -2685,7 +2694,6 @@ void P_DemoCameraMovement(camera_t *cam)
 {
 	ticcmd_t *cmd = &cameracmd;;
 	angle_t thrustangle;
-	mobj_t *awayviewmobj_hack;
 	player_t *lastp;
 
 	// update democam stuff with what we got here:
@@ -2734,14 +2742,6 @@ void P_DemoCameraMovement(camera_t *cam)
 		// besides freecam going inside walls sounds pretty cool on paper.
 	}
 
-	// awayviewmobj hack; this is to prevent us from hearing sounds from the player's perspective
-
-	awayviewmobj_hack = P_SpawnMobj(cam->x, cam->y, cam->z, MT_THOK);
-	awayviewmobj_hack->tics = 2;
-	awayviewmobj_hack->renderflags |= RF_DONTDRAW;
-
-	democam.soundmobj = awayviewmobj_hack;
-
 	// update subsector to avoid crashes;
 	cam->subsector = R_PointInSubsectorFast(cam->x, cam->y);
 }
@@ -2812,8 +2812,6 @@ boolean P_MoveChaseCamera(player_t *player, camera_t *thiscam, boolean resetcall
 	thiscam->old_angle = thiscam->angle;
 	thiscam->old_aiming = thiscam->aiming;
 
-	democam.soundmobj = NULL;	// reset this each frame, we don't want the game crashing for stupid reasons now do we
-
 	// We probably shouldn't move the camera if there is no player or player mobj somehow
 	if (!player || !player->mo)
 		return true;

src/s_sound.c

@@ -545,11 +545,6 @@ void S_StartSoundAtVolume(const void *origin_p, sfxenum_t sfx_id, INT32 volume)
 			continue;
 		}
 
-		if (i == 0 && democam.soundmobj)
-		{
-			continue;
-		}
-
 		if (player->awayviewtics)
 		{
 			listenmobj[i] = player->awayviewmobj;
@@ -559,7 +554,7 @@ void S_StartSoundAtVolume(const void *origin_p, sfxenum_t sfx_id, INT32 volume)
 			listenmobj[i] = player->mo;
 		}
 
-		if (origin && origin == listenmobj[i])
+		if (origin && origin == listenmobj[i] && !demo.freecam)
 		{
 			itsUs = true;
 		}
@@ -810,11 +805,6 @@ void S_UpdateSounds(void)
 			continue;
 		}
 
-		if (i == 0 && democam.soundmobj)
-		{
-			continue;
-		}
-
 		if (player->awayviewtics)
 		{
 			listenmobj[i] = player->awayviewmobj;
@@ -881,12 +871,15 @@ void S_UpdateSounds(void)
 				{
 					boolean itsUs = false;
 
-					for (i = r_splitscreen; i >= 0; i--)
+					if (!demo.freecam)
 					{
-						if (c->origin != listenmobj[i])
-							continue;
+						for (i = r_splitscreen; i >= 0; i--)
+						{
+							if (c->origin != listenmobj[i])
+								continue;
 
-						itsUs = true;
+							itsUs = true;
+						}
 					}
 
 					if (itsUs == false)