Add S-Monitor power-up

- Give Invincibility effect to player
- Bumping players does not extend Invincibility time while
  power-up is active

src/d_player.h

@@ -463,6 +463,7 @@ typedef struct {
 
 // player_t struct for power-ups
 struct powerupvars_t {
+	UINT16 superTimer;
 	mobj_t *flickyController;
 };
 

src/k_kart.c

@@ -8090,6 +8090,11 @@ void K_KartPlayerThink(player_t *player, ticcmd_t *cmd)
 		}
 	}
 
+	if (player->powerup.superTimer > 0)
+	{
+		player->powerup.superTimer--;
+	}
+
 	if (player->guardCooldown)
 		player->guardCooldown--;
 		

src/k_powerup.cpp

@@ -8,6 +8,9 @@ tic_t K_PowerUpRemaining(const player_t* player, kartitems_t powerup)
 {
 	switch (powerup)
 	{
+	case POWERUP_SMONITOR:
+		return player->powerup.superTimer;
+
 	case POWERUP_SUPERFLICKY:
 		return Obj_SuperFlickySwarmTime(player->powerup.flickyController);
 
@@ -20,6 +23,11 @@ void K_GivePowerUp(player_t* player, kartitems_t powerup, tic_t time)
 {
 	switch (powerup)
 	{
+	case POWERUP_SMONITOR:
+		K_DoInvincibility(player, time);
+		player->powerup.superTimer += time;
+		break;
+
 	case POWERUP_SUPERFLICKY:
 		if (K_PowerUpRemaining(player, POWERUP_SUPERFLICKY))
 		{
@@ -38,6 +46,19 @@ void K_GivePowerUp(player_t* player, kartitems_t powerup, tic_t time)
 
 void K_DropPowerUps(player_t* player)
 {
+	auto simple_drop = [player](kartitems_t powerup, auto& timer)
+	{
+		tic_t remaining = K_PowerUpRemaining(player, powerup);
+
+		if (remaining)
+		{
+			K_DropPaperItem(player, powerup, remaining);
+			timer = 0;
+		}
+	};
+
+	simple_drop(POWERUP_SMONITOR, player->powerup.superTimer);
+
 	if (K_PowerUpRemaining(player, POWERUP_SUPERFLICKY))
 	{
 		mobj_t* swarm = player->powerup.flickyController;

src/p_inter.c

@@ -2418,7 +2418,8 @@ boolean P_DamageMobj(mobj_t *target, mobj_t *inflictor, mobj_t *source, INT32 da
 				if (source && source != player->mo && source->player)
 				{
 					// Extend the invincibility if the hit was a direct hit.
-					if (inflictor == source && source->player->invincibilitytimer)
+					if (inflictor == source && source->player->invincibilitytimer &&
+							!K_PowerUpRemaining(player, POWERUP_SMONITOR))
 					{
 						tic_t kinvextend;
 

src/p_saveg.c

@@ -634,6 +634,9 @@ static void P_NetArchivePlayers(savebuffer_t *save)
 		// ACS has read access to this, so it has to be net-communicated.
 		// It is the ONLY roundcondition that is sent over the wire and I'd like it to stay that way.
 		WRITEUINT32(save->p, players[i].roundconditions.unlocktriggers);
+
+		// powerupvars_t
+		WRITEUINT16(save->p, players[i].powerup.superTimer);
 	}
 }
 
@@ -1059,6 +1062,9 @@ static void P_NetUnArchivePlayers(savebuffer_t *save)
 		// It is the ONLY roundcondition that is sent over the wire and I'd like it to stay that way.
 		players[i].roundconditions.unlocktriggers = READUINT32(save->p);
 
+		// powerupvars_t
+		players[i].powerup.superTimer = READUINT16(save->p);
+
 		//players[i].viewheight = P_GetPlayerViewHeight(players[i]); // scale cannot be factored in at this point
 	}
 }