[swift] cleanup functions

include/XPMPMultiplayer.h

@@ -272,6 +272,22 @@ const char *	XPMPMultiplayerInit(
  */
 const char *	XPMPMultiplayerEnable(void);
 
+/*
+ * XPMPMultiplayerDisable
+ *
+ * Disable drawing of multiplayer planes.  Call this from XPluginDisable to release multiplayer.
+ * Reverses the actions on XPMPMultiplayerEnable.
+ */
+void XPMPMultiplayerDisable(void);
+
+/*
+ * XPMPMultiplayerCleanup
+ *
+ * Clean up the multiplayer library. Call this from XPluginStop to reverse the actions of
+ * XPMPMultiplayerInit as much as possible.
+ */
+void XPMPMultiplayerCleanup(void);
+
 /*
  * XPMPLoadPlanesIfNecessary
  *

src/XPMPMultiplayer.cpp

@@ -150,6 +150,13 @@ const char * 	XPMPMultiplayerInit(
 	else 				return "";
 }
 
+void XPMPMultiplayerCleanup(void)
+{
+    XPLMUnregisterDrawCallback(XPMPControlPlaneCount, xplm_Phase_Gauges, 0, 0);
+    XPLMUnregisterDrawCallback(XPMPControlPlaneCount, xplm_Phase_Gauges, 1, (void *) -1);
+    XPLMUnregisterDrawCallback(XPMPRenderMultiplayerPlanes, xplm_Phase_Airplanes, 0, 0);
+}
+
 
 // We use this array to track Austin's planes, since we have to mess with them.
 static	vector<string>	gPlanePaths;
@@ -210,6 +217,11 @@ const  char * XPMPMultiplayerEnable(void)
 		return "";
 }
 
+void XPMPMultiplayerDisable(void)
+{
+    XPLMReleasePlanes();
+}
+
 
 // This routine checks plane loading and grabs anyone we're missing.
 void	XPMPLoadPlanesIfNecessary(void)