Backported HOOK_GAMEMODECHANGE from 4.2

Backported SPECIAL game mode flag from 4.2

artifacts/scripting/headers/sfall.h

@@ -22,6 +22,7 @@
 #define HEROWIN     (0x40000)
 #define DIALOGVIEW  (0x80000)
 #define COUNTERWIN  (0x100000) // counter window for moving multiple items or setting a timer
+#define SPECIAL     (0x80000000)
 
 //Valid arguments to register_hook
 #define HOOK_TOHIT            (0)
@@ -50,6 +51,7 @@
 #define HOOK_WITHINPERCEPTION (23)
 #define HOOK_INVENTORYMOVE    (24)
 #define HOOK_INVENWIELD       (25)
+#define HOOK_GAMEMODECHANGE   (31)
 
 //Valid arguments to list_begin
 #define LIST_CRITTERS    (0)

artifacts/scripting/hookscripts.txt

@@ -462,3 +462,12 @@ int     arg3 - 1 when wielding, 0 when unwielding
 int     arg4 - 1 when removing an equipped item from inventory, 0 otherwise
 
 int     ret0 - overrides hard-coded handler (-1 - use engine handler, any other value - override) - NOT RECOMMENDED
+
+-------------------------------------------
+
+HOOK_GAMEMODECHANGE (hs_gamemodechange.int)
+
+Runs once every time when the game mode was changed, like opening/closing the inventory, character screen, pipboy, etc.
+
+int     arg0 - event type: 1 - when the player exits the game, 0 - otherwise
+int     arg1 - the previous game mode