Add GUI/client setting to save zoning overlay state

src/settings.cpp

@@ -66,6 +66,7 @@
 #include "strings_func.h"
 #include "string_func.h"
 #include "debug.h"
+#include "zoning.h"
 
 #include "void_map.h"
 #include "station_base.h"

src/table/misc_settings.ini

@@ -319,5 +319,23 @@ min      = ZOOM_LVL_MIN
 max      = ZOOM_LVL_OUT_4X
 cat      = SC_BASIC
 
+[SDTG_VAR]
+name     = ""zoning_overlay_inner""
+type     = SLE_UINT8
+var      = _zoning.inner
+def      = 0
+min      = 0
+max      = ZEM_END
+cat      = SC_BASIC
+
+[SDTG_VAR]
+name     = ""zoning_overlay_outer""
+type     = SLE_UINT8
+var      = _zoning.outer
+def      = 0
+min      = 0
+max      = ZEM_END
+cat      = SC_BASIC
+
 [SDTG_END]
 

src/zoning.h

@@ -29,6 +29,8 @@ enum ZoningEvaluationMode {
 	ZEM_TRACERESTRICT, ///< Check for restricted signals
 	ZEM_2x2_GRID,      ///< Show 2x2 town road grid
 	ZEM_3x3_GRID,      ///< Show 3x3 town road grid
+
+	ZEM_END,           ///< End marker
 };
 
 /**