From 20aa7c75de533866c5659d5af070207acf212975 Mon Sep 17 00:00:00 2001
From: Christoph Oelckers <c.oelckers@zdoom.fake>
Date: Sun, 7 Feb 2016 00:30:27 +0100
Subject: [PATCH] - added the case '0: switch the portal of to P_ChangePortal.

---
 src/portal.cpp | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/portal.cpp b/src/portal.cpp
index fbbe5c95c..7f08e6d6e 100644
--- a/src/portal.cpp
+++ b/src/portal.cpp
@@ -165,8 +165,13 @@ static bool ChangePortalLine(line_t *line, int destid)
 	if (line->portalindex >= linePortals.Size()) return false;
 	FLinePortal *port = &linePortals[line->portalindex];
 	if (port->mType == PORTT_LINKED) return false;	// linked portals cannot be changed.
+	if (destid == 0) port->mDestination = NULL;
 	port->mDestination = FindDestination(line, destid);
-	if (port->mType == PORTT_INTERACTIVE)
+	if (port->mDestination == NULL)
+	{
+		port->mFlags = 0;
+	}
+	else if (port->mType == PORTT_INTERACTIVE)
 	{
 		FLinePortal *portd = &linePortals[port->mDestination->portalindex];
 		if (portd != NULL && portd->mType == PORTT_INTERACTIVE && portd->mDestination == line)