(svn r22241) -Codechange: Add additional to-be-used parameter to OnInvalidateData().

40 files changed, 427 insertions, 69 deletions

diff --git a/src/ai/ai_gui.cpp b/src/ai/ai_gui.cpp
index 1bc7ad9de..e16644d4f 100644
--- a/src/ai/ai_gui.cpp
+++ b/src/ai/ai_gui.cpp
@@ -182,8 +182,14 @@ struct AIListWindow : public Window {
 		nwi->widget_data = (this->vscroll->GetCapacity() << MAT_ROW_START) + (1 << MAT_COL_START);
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		if (_game_mode == GM_NORMAL && Company::IsValidID(this->slot)) {
 			delete this;
 			return;
@@ -437,8 +443,14 @@ struct AISettingsWindow : public Window {
 		}
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		if (_game_mode == GM_NORMAL && Company::IsValidID(this->slot)) delete this;
 	}
 };
@@ -692,8 +704,14 @@ struct AIConfigWindow : public Window {
 		}
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		if (!IsEditable(this->selected_slot)) {
 			this->selected_slot = INVALID_COMPANY;
 		}
@@ -1032,8 +1050,14 @@ struct AIDebugWindow : public QueryStringBaseWindow {
 		return state;
 	}
 
-	virtual void OnInvalidateData(int data = 0)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		if (data == -1 || ai_debug_company == data) this->SetDirty();
 
 		if (data == -2) {
diff --git a/src/autoreplace_gui.cpp b/src/autoreplace_gui.cpp
index 6182953d0..000df7963 100644
--- a/src/autoreplace_gui.cpp
+++ b/src/autoreplace_gui.cpp
@@ -491,8 +491,14 @@ public:
 				this->GetWidget<NWidgetCore>(RVW_WIDGET_RIGHT_MATRIX)->widget_data = (this->vscroll[0]->GetCapacity() << MAT_ROW_START) + (1 << MAT_COL_START);
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		if (data != 0) {
 			this->engines[0].ForceRebuild();
 		} else {
diff --git a/src/build_vehicle_gui.cpp b/src/build_vehicle_gui.cpp
index dd3d8731d..2caa42d9d 100644
--- a/src/build_vehicle_gui.cpp
+++ b/src/build_vehicle_gui.cpp
@@ -1218,8 +1218,14 @@ struct BuildVehicleWindow : Window {
 		}
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		/* When switching to original acceleration model for road vehicles, clear the selected sort criteria if it is not available now. */
 		if (this->vehicle_type == VEH_ROAD &&
 				_settings_game.vehicle.roadveh_acceleration_model == AM_ORIGINAL &&
diff --git a/src/company_gui.cpp b/src/company_gui.cpp
index 8471ccfe3..7c45f3fed 100644
--- a/src/company_gui.cpp
+++ b/src/company_gui.cpp
@@ -800,8 +800,14 @@ public:
 		}
 	}
 
-	virtual void OnInvalidateData(int data = 0)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		this->SetWidgetsDisabledState(true, SCLW_WIDGET_CLASS_RAIL, SCLW_WIDGET_CLASS_ROAD, SCLW_WIDGET_CLASS_SHIP, SCLW_WIDGET_CLASS_AIRCRAFT, WIDGET_LIST_END);
 
 		bool current_class_valid = this->livery_class == LC_OTHER;
diff --git a/src/depot_gui.cpp b/src/depot_gui.cpp
index d3866af42..095d67b57 100644
--- a/src/depot_gui.cpp
+++ b/src/depot_gui.cpp
@@ -635,8 +635,14 @@ struct DepotWindow : Window {
 		}
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		this->generate_list = true;
 	}
 
diff --git a/src/dock_gui.cpp b/src/dock_gui.cpp
index 8e667ec3c..f7c50fc6a 100644
--- a/src/dock_gui.cpp
+++ b/src/dock_gui.cpp
@@ -119,8 +119,14 @@ struct BuildDocksToolbarWindow : Window {
 		if (_settings_client.gui.link_terraform_toolbar) DeleteWindowById(WC_SCEN_LAND_GEN, 0, false);
 	}
 
-	void OnInvalidateData(int data = 0)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		this->SetWidgetsDisabledState(!CanBuildVehicleInfrastructure(VEH_SHIP),
 			DTW_DEPOT,
 			DTW_STATION,
diff --git a/src/fios_gui.cpp b/src/fios_gui.cpp
index c9bc284f5..c87167882 100644
--- a/src/fios_gui.cpp
+++ b/src/fios_gui.cpp
@@ -659,8 +659,14 @@ public:
 		this->vscroll->SetCapacityFromWidget(this, SLWW_DRIVES_DIRECTORIES_LIST);
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		switch (data) {
 			case 0:
 				/* Rescan files */
diff --git a/src/genworld_gui.cpp b/src/genworld_gui.cpp
index 5104154d6..fffdb1587 100644
--- a/src/genworld_gui.cpp
+++ b/src/genworld_gui.cpp
@@ -425,8 +425,14 @@ struct GenerateLandscapeWindow : public QueryStringBaseWindow {
 		}
 	}
 
-	virtual void OnInvalidateData(int data = 0)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		/* Update the climate buttons */
 		this->SetWidgetLoweredState(GLAND_TEMPERATE, _settings_newgame.game_creation.landscape == LT_TEMPERATE);
 		this->SetWidgetLoweredState(GLAND_ARCTIC,    _settings_newgame.game_creation.landscape == LT_ARCTIC);
diff --git a/src/graph_gui.cpp b/src/graph_gui.cpp
index 28ccf2bed..6354366b0 100644
--- a/src/graph_gui.cpp
+++ b/src/graph_gui.cpp
@@ -91,8 +91,14 @@ struct GraphLegendWindow : Window {
 		InvalidateWindowData(WC_COMPANY_VALUE, 0);
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		if (Company::IsValidID(data)) return;
 
 		SetBit(_legend_excluded_companies, data);
@@ -543,8 +549,14 @@ public:
 		this->UpdateStatistics(false);
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		this->UpdateStatistics(true);
 	}
 
@@ -1013,8 +1025,14 @@ struct PaymentRatesGraphWindow : BaseGraphWindow {
 		/* Override default OnTick */
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		this->OnHundredthTick();
 	}
 
@@ -1247,8 +1265,14 @@ public:
 		}
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		if (data == 0) {
 			this->companies.ForceRebuild();
 		} else {
@@ -1488,11 +1512,13 @@ struct PerformanceRatingDetailWindow : Window {
 	}
 
 	/**
-	 * Invalidate the data of this window.
+	 * Some data on this window has become invalid.
 	 * @param data the company ID of the company that is going to be removed
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
 	 */
-	virtual void OnInvalidateData(int data)
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		/* Disable the companies who are not active */
 		for (CompanyID i = COMPANY_FIRST; i < MAX_COMPANIES; i++) {
 			this->SetWidgetDisabledState(i + PRW_COMPANY_FIRST, !Company::IsValidID(i));
diff --git a/src/group_gui.cpp b/src/group_gui.cpp
index 6f23af3fb..906b099ec 100644
--- a/src/group_gui.cpp
+++ b/src/group_gui.cpp
@@ -253,8 +253,14 @@ public:
 		}
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		/* We can only set the trigger for resorting/rebuilding.
 		 * We cannot safely resort at this point, as there might be multiple scheduled invalidations,
 		 * and a rebuild needs to be done first though it is scheduled later. */
diff --git a/src/industry_gui.cpp b/src/industry_gui.cpp
index 012d0a39d..bc72f1965 100644
--- a/src/industry_gui.cpp
+++ b/src/industry_gui.cpp
@@ -597,8 +597,14 @@ public:
 		this->RaiseButtons();
 	}
 
-	virtual void OnInvalidateData(int data = 0)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		this->SetupArrays();
 
 		const IndustrySpec *indsp = (this->selected_type == INVALID_INDUSTRYTYPE) ? NULL : GetIndustrySpec(this->selected_type);
@@ -947,8 +953,14 @@ public:
 		this->SetDirty();
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		const Industry *i = Industry::Get(this->window_number);
 		if (IsProductionAlterable(i)) {
 			const IndustrySpec *ind = GetIndustrySpec(i->type);
@@ -1346,8 +1358,14 @@ public:
 		this->BuildSortIndustriesList();
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		/* We can only set the trigger for resorting/rebuilding.
 		 * We cannot safely resort at this point, as there might be multiple scheduled invalidations,
 		 * and a rebuild needs to be done first though it is scheduled later. */
@@ -2394,13 +2412,15 @@ struct IndustryCargoesWindow : public Window {
 	}
 
 	/**
-	 * Notify the window about external events.
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
 	 * - data = 0 .. NUM_INDUSTRYTYPES - 1: Display the chain around the given industry.
 	 * - data = NUM_INDUSTRYTYPES: Stop sending updates to the smallmap window.
-	 * @param data The event.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
 	 */
-	virtual void OnInvalidateData(int data)
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		if (data == NUM_INDUSTRYTYPES) {
 			if (this->IsWidgetLowered(ICW_NOTIFY)) {
 				this->RaiseWidget(ICW_NOTIFY);
diff --git a/src/intro_gui.cpp b/src/intro_gui.cpp
index 8f8458cbb..1f5692d42 100644
--- a/src/intro_gui.cpp
+++ b/src/intro_gui.cpp
@@ -55,8 +55,14 @@ struct SelectGameWindow : public Window {
 		this->OnInvalidateData();
 	}
 
-	virtual void OnInvalidateData(int data = 0)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		this->SetWidgetLoweredState(SGI_TEMPERATE_LANDSCAPE, _settings_newgame.game_creation.landscape == LT_TEMPERATE);
 		this->SetWidgetLoweredState(SGI_ARCTIC_LANDSCAPE,    _settings_newgame.game_creation.landscape == LT_ARCTIC);
 		this->SetWidgetLoweredState(SGI_TROPIC_LANDSCAPE,    _settings_newgame.game_creation.landscape == LT_TROPIC);
diff --git a/src/main_gui.cpp b/src/main_gui.cpp
index ed85860da..45f2d7ebb 100644
--- a/src/main_gui.cpp
+++ b/src/main_gui.cpp
@@ -432,8 +432,14 @@ struct MainWindow : Window
 		}
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		/* Forward the message to the appropiate toolbar (ingame or scenario editor) */
 		InvalidateWindowData(WC_MAIN_TOOLBAR, 0, data, true);
 	}
diff --git a/src/misc_gui.cpp b/src/misc_gui.cpp
index c86f6c6a3..4f97bcbf4 100644
--- a/src/misc_gui.cpp
+++ b/src/misc_gui.cpp
@@ -332,8 +332,14 @@ public:
 		::ShowNewGRFInspectWindow(GetGrfSpecFeature(this->tile), this->tile);
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		switch (data) {
 			case 1:
 				/* ReInit, "debug" sprite might have changed */
@@ -639,8 +645,14 @@ public:
 		return pt;
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		/* If company gets shut down, while displaying an error about it, remove the error message. */
 		if (this->face != INVALID_COMPANY && !Company::IsValidID(this->face)) delete this;
 	}
diff --git a/src/music_gui.cpp b/src/music_gui.cpp
index a0cb8ac9b..3a03fb152 100644
--- a/src/music_gui.cpp
+++ b/src/music_gui.cpp
@@ -313,8 +313,14 @@ struct MusicTrackSelectionWindow : public Window {
 		}
 	}
 
-	virtual void OnInvalidateData(int data = 0)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		for (int i = 0; i < 6; i++) {
 			this->SetWidgetLoweredState(MTSW_ALL + i, i == _settings_client.music.playlist);
 		}
@@ -638,8 +644,14 @@ struct MusicWindow : public Window {
 		}
 	}
 
-	virtual void OnInvalidateData(int data = 0)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		for (int i = 0; i < 6; i++) {
 			this->SetWidgetLoweredState(MW_ALL + i, i == _settings_client.music.playlist);
 		}
diff --git a/src/network/network_chat_gui.cpp b/src/network/network_chat_gui.cpp
index e610f9cbf..ac7045d8c 100644
--- a/src/network/network_chat_gui.cpp
+++ b/src/network/network_chat_gui.cpp
@@ -531,8 +531,14 @@ struct NetworkChatWindow : public QueryStringBaseWindow {
 		ShowOnScreenKeyboard(this, wid, NWCW_CLOSE, NWCW_SENDBUTTON);
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		if (data == this->dest) delete this;
 	}
 };
diff --git a/src/network/network_content_gui.cpp b/src/network/network_content_gui.cpp
index ee3a325d9..13e0b5d59 100644
--- a/src/network/network_content_gui.cpp
+++ b/src/network/network_content_gui.cpp
@@ -751,8 +751,14 @@ public:
 		this->InvalidateData();
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		if (this->content.NeedRebuild()) this->BuildContentList();
 
 		/* To sum all the bytes we intend to download */
diff --git a/src/network/network_gui.cpp b/src/network/network_gui.cpp
index e62f2bcae..5cb031d01 100644
--- a/src/network/network_gui.cpp
+++ b/src/network/network_gui.cpp
@@ -794,8 +794,14 @@ public:
 		if (this->field == NGWW_CLIENT) this->HandleEditBox(NGWW_CLIENT);
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		if (data == 1) {
 			this->server = NULL;
 			this->list_pos = SLP_INVALID;
diff --git a/src/newgrf_debug_gui.cpp b/src/newgrf_debug_gui.cpp
index b96ecbd7f..40581b9b2 100644
--- a/src/newgrf_debug_gui.cpp
+++ b/src/newgrf_debug_gui.cpp
@@ -772,8 +772,14 @@ struct SpriteAlignerWindow : Window {
 		this->SetDirty();
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		if (data == 1) {
 			/* Sprite picker finished */
 			this->RaiseWidget(SAW_PICKER);
diff --git a/src/newgrf_gui.cpp b/src/newgrf_gui.cpp
index 2034ae6ab..a1e45e3cc 100644
--- a/src/newgrf_gui.cpp
+++ b/src/newgrf_gui.cpp
@@ -379,8 +379,14 @@ struct NewGRFParametersWindow : public Window {
 		nwi->widget_data = (this->vscroll->GetCapacity() << MAT_ROW_START) + (1 << MAT_COL_START);
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		if (!this->action14present) {
 			this->SetWidgetDisabledState(GRFPAR_WIDGET_NUMPAR_DEC, this->grf_config->num_params == 0);
 			this->SetWidgetDisabledState(GRFPAR_WIDGET_NUMPAR_INC, this->grf_config->num_params >= this->grf_config->num_valid_params);
@@ -1025,15 +1031,18 @@ struct NewGRFWindow : public QueryStringBaseWindow {
 	}
 
 	/**
-	 * Calback to update internal data.
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
 	 *  - 0: (optionally) build availables, update button status.
 	 *  - 1: build availables, Add newly found grfs, update button status.
 	 *  - 2: (optionally) build availables, Reset preset, + 3
 	 *  - 3: (optionally) build availables, Update active scrollbar, update button status.
 	 *  - 4: Force a rebuild of the availables, + 2
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
 	 */
-	virtual void OnInvalidateData(int data = 0)
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		switch (data) {
 			default: NOT_REACHED();
 			case 0:
diff --git a/src/news_gui.cpp b/src/news_gui.cpp
index a958e6392..4289285fc 100644
--- a/src/news_gui.cpp
+++ b/src/news_gui.cpp
@@ -498,8 +498,14 @@ struct NewsWindow : Window {
 		return ES_NOT_HANDLED;
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		/* The chatbar has notified us that is was either created or closed */
 		int newtop = this->top + this->chat_height - data;
 		this->chat_height = data;
@@ -1035,8 +1041,14 @@ struct MessageHistoryWindow : Window {
 		}
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		this->vscroll->SetCount(_total_news);
 	}
 
@@ -1201,8 +1213,14 @@ struct MessageOptionsWindow : Window {
 		}
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		/* Update the dropdown value for 'set all categories'. */
 		this->GetWidget<NWidgetCore>(WIDGET_NEWSOPT_DROP_SUMMARY)->widget_data = this->message_opt[this->state];
 
diff --git a/src/order_gui.cpp b/src/order_gui.cpp
index eefeddbfb..f12b104cc 100644
--- a/src/order_gui.cpp
+++ b/src/order_gui.cpp
@@ -805,8 +805,14 @@ public:
 		}
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		VehicleOrderID from = INVALID_VEH_ORDER_ID;
 		VehicleOrderID to   = INVALID_VEH_ORDER_ID;
 
diff --git a/src/osk_gui.cpp b/src/osk_gui.cpp
index 0edb2eea3..cd323b362 100644
--- a/src/osk_gui.cpp
+++ b/src/osk_gui.cpp
@@ -247,8 +247,14 @@ struct OskWindow : public Window {
 		this->parent->SetWidgetDirty(this->text_btn);
 	}
 
-	virtual void OnInvalidateData(int)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		this->SetWidgetDirty(OSK_WIDGET_TEXT);
 	}
 };
diff --git a/src/rail_gui.cpp b/src/rail_gui.cpp
index 2b391218b..36576a3ca 100644
--- a/src/rail_gui.cpp
+++ b/src/rail_gui.cpp
@@ -1617,8 +1617,14 @@ public:
 		this->InvalidateData();
 	}
 
-	virtual void OnInvalidateData(int data = 0)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		this->LowerWidget((_cur_signal_variant == SIG_ELECTRIC ? BSW_ELECTRIC_NORM : BSW_SEMAPHORE_NORM) + _cur_signal_type);
 
 		this->SetWidgetLoweredState(BSW_CONVERT, _convert_signal_button);
diff --git a/src/road_gui.cpp b/src/road_gui.cpp
index 0a9951314..9637240f3 100644
--- a/src/road_gui.cpp
+++ b/src/road_gui.cpp
@@ -341,8 +341,14 @@ struct BuildRoadToolbarWindow : Window {
 		if (_settings_client.gui.link_terraform_toolbar) DeleteWindowById(WC_SCEN_LAND_GEN, 0, false);
 	}
 
-	void OnInvalidateData(int data = 0)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		this->SetWidgetsDisabledState(!CanBuildVehicleInfrastructure(VEH_ROAD),
 				RTW_DEPOT,
 				RTW_BUS_STATION,
diff --git a/src/settings_gui.cpp b/src/settings_gui.cpp
index 751075a20..0203b7574 100644
--- a/src/settings_gui.cpp
+++ b/src/settings_gui.cpp
@@ -460,8 +460,14 @@ struct GameOptionsWindow : Window {
 		}
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		this->SetWidgetLoweredState(GOW_FULLSCREEN_BUTTON, _fullscreen);
 
 		bool missing_files = BaseGraphics::GetUsedSet()->GetNumMissing() == 0;
@@ -724,8 +730,14 @@ public:
 		}
 	}
 
-	virtual void OnInvalidateData(int data = 0)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		uint i;
 		const SettingDesc *sd = GetSettingFromName("difficulty.max_no_competitors", &i);
 		for (i = 0; i < GAME_DIFFICULTY_NUM; i++, sd++) {
diff --git a/src/signs_gui.cpp b/src/signs_gui.cpp
index f3101e99a..d639e1dcc 100644
--- a/src/signs_gui.cpp
+++ b/src/signs_gui.cpp
@@ -367,8 +367,14 @@ struct SignListWindow : QueryStringBaseWindow, SignList {
 		this->SetDirty();
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		/* When there is a filter string, we always need to rebuild the list even if
 		 * the amount of signs in total is unchanged, as the subset of signs that is
 		 * accepted by the filter might has changed.
diff --git a/src/smallmap_gui.cpp b/src/smallmap_gui.cpp
index b7bcd9c20..2fd86623d 100644
--- a/src/smallmap_gui.cpp
+++ b/src/smallmap_gui.cpp
@@ -1423,12 +1423,15 @@ public:
 	}
 
 	/**
-	 * Notifications for the smallmap window.
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
 	 * - data = 0: Displayed industries at the industry chain window have changed.
 	 * - data = 1: Companies have changed.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
 	 */
-	virtual void OnInvalidateData(int data)
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		switch (data) {
 			case 1:
 				/* The owner legend has already been rebuilt. */
diff --git a/src/station_gui.cpp b/src/station_gui.cpp
index fc27ae615..cb40cb37d 100644
--- a/src/station_gui.cpp
+++ b/src/station_gui.cpp
@@ -687,8 +687,14 @@ public:
 		this->vscroll->SetCapacityFromWidget(this, SLW_LIST, WD_FRAMERECT_TOP + WD_FRAMERECT_BOTTOM);
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		/* We can only set the trigger for resorting/rebuilding.
 		 * We cannot safely resort at this point, as there might be multiple scheduled invalidations,
 		 * and a rebuild needs to be done first though it is scheduled later. */
@@ -1451,8 +1457,14 @@ struct SelectStationWindow : Window {
 		this->vscroll->SetCapacityFromWidget(this, JSW_PANEL, WD_FRAMERECT_TOP + WD_FRAMERECT_BOTTOM);
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		FindStationsNearby<T>(this->area, true);
 		this->vscroll->SetCount(_stations_nearby_list.Length() + 1);
 		this->SetDirty();
diff --git a/src/statusbar_gui.cpp b/src/statusbar_gui.cpp
index 4c1184336..82ffeb239 100644
--- a/src/statusbar_gui.cpp
+++ b/src/statusbar_gui.cpp
@@ -183,8 +183,14 @@ struct StatusBarWindow : Window {
 		}
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		switch (data) {
 			default: NOT_REACHED();
 			case SBI_SAVELOAD_START:  this->saving = true;  break;
diff --git a/src/subsidy_gui.cpp b/src/subsidy_gui.cpp
index 0b9182fdd..9e31fb970 100644
--- a/src/subsidy_gui.cpp
+++ b/src/subsidy_gui.cpp
@@ -215,8 +215,14 @@ struct SubsidyListWindow : Window {
 		this->vscroll->SetCapacityFromWidget(this, SLW_PANEL);
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		this->vscroll->SetCount(this->CountLines());
 	}
 };
diff --git a/src/timetable_gui.cpp b/src/timetable_gui.cpp
index 4f991323b..51cd82982 100644
--- a/src/timetable_gui.cpp
+++ b/src/timetable_gui.cpp
@@ -243,8 +243,14 @@ struct TimetableWindow : Window {
 		return (sel < v->GetNumOrders() * 2 && sel >= 0) ? sel : INVALID_ORDER;
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		switch (data) {
 			case -666:
 				/* Autoreplace replaced the vehicle */
diff --git a/src/toolbar_gui.cpp b/src/toolbar_gui.cpp
index e57b2f101..711b73846 100644
--- a/src/toolbar_gui.cpp
+++ b/src/toolbar_gui.cpp
@@ -1482,8 +1482,14 @@ struct MainToolbarWindow : Window {
 		}
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		if (FindWindowById(WC_MAIN_WINDOW, 0) != NULL) HandleZoomMessage(this, FindWindowById(WC_MAIN_WINDOW, 0)->viewport, TBN_ZOOMIN, TBN_ZOOMOUT);
 	}
 
@@ -1792,8 +1798,14 @@ struct ScenarioEditorToolbarWindow : Window {
 		}
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		if (FindWindowById(WC_MAIN_WINDOW, 0) != NULL) HandleZoomMessage(this, FindWindowById(WC_MAIN_WINDOW, 0)->viewport, TBSE_ZOOMIN, TBSE_ZOOMOUT);
 	}
 
diff --git a/src/town_gui.cpp b/src/town_gui.cpp
index cbcb43f20..016399e70 100644
--- a/src/town_gui.cpp
+++ b/src/town_gui.cpp
@@ -523,8 +523,14 @@ public:
 		}
 	}
 
-	virtual void OnInvalidateData(int data = 0)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		/* Called when setting station noise or required cargos have changed, in order to resize the window */
 		this->SetDirty(); // refresh display for current size. This will allow to avoid glitches when downgrading
 		this->ResizeWindowAsNeeded();
@@ -863,8 +869,14 @@ public:
 		this->vscroll->SetCapacityFromWidget(this, TDW_CENTERTOWN);
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		/* We can only set the trigger for resorting/rebuilding.
 		 * We cannot safely resort at this point, as there might be multiple scheduled invalidations,
 		 * and a rebuild needs to be done first though it is scheduled later. */
@@ -1165,8 +1177,14 @@ public:
 		this->UpdateButtons(false);
 	}
 
-	virtual void OnInvalidateData(int)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		this->UpdateButtons(true);
 	}
 };
diff --git a/src/transparency_gui.cpp b/src/transparency_gui.cpp
index cc8c399f6..cf1979e38 100644
--- a/src/transparency_gui.cpp
+++ b/src/transparency_gui.cpp
@@ -125,8 +125,14 @@ public:
 		return pt;
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		for (uint i = TTW_WIDGET_BEGIN; i < TTW_WIDGET_END; i++) {
 			this->SetWidgetLoweredState(i, IsTransparencySet((TransparencyOption)(i - TTW_WIDGET_BEGIN)));
 		}
diff --git a/src/tree_gui.cpp b/src/tree_gui.cpp
index ebbd2d189..8623a3ff5 100644
--- a/src/tree_gui.cpp
+++ b/src/tree_gui.cpp
@@ -144,8 +144,14 @@ public:
 		}
 	}
 
-	virtual void OnInvalidateData(int data = 0)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		this->base  = _tree_base_by_landscape[_settings_game.game_creation.landscape];
 		this->count = _tree_count_by_landscape[_settings_game.game_creation.landscape];
 	}
diff --git a/src/vehicle_gui.cpp b/src/vehicle_gui.cpp
index f8ff6d5c1..26b8666a3 100644
--- a/src/vehicle_gui.cpp
+++ b/src/vehicle_gui.cpp
@@ -683,8 +683,14 @@ struct RefitWindow : public Window {
 		}
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		switch (data) {
 			case -666:
 				/* Autoreplace replaced the vehicle.
@@ -1600,8 +1606,14 @@ public:
 		this->GetWidget<NWidgetCore>(VLW_WIDGET_LIST)->widget_data = (this->vscroll->GetCapacity() << MAT_ROW_START) + (1 << MAT_COL_START);
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		if (HasBit(data, 31) && this->vli.type == VL_SHARED_ORDERS) {
 			this->vli.index = GB(data, 0, 20);
 			this->window_number = this->vli.Pack();
@@ -1787,8 +1799,14 @@ struct VehicleDetailsWindow : Window {
 		this->tab = TDW_TAB_CARGO;
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		if (data == -666) {
 			/* Autoreplace replaced the vehicle.
 			 * Nothing to do for this window though.
@@ -2596,8 +2614,14 @@ public:
 		}
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		if (data == -666) {
 			/* Autoreplace replaced the vehicle.
 			 * Nothing to do for this window though.
diff --git a/src/viewport_gui.cpp b/src/viewport_gui.cpp
index 1a85311b6..103b27cb2 100644
--- a/src/viewport_gui.cpp
+++ b/src/viewport_gui.cpp
@@ -148,8 +148,14 @@ public:
 		}
 	}
 
-	virtual void OnInvalidateData(int data = 0)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		/* Only handle zoom message if intended for us (msg ZOOM_IN/ZOOM_OUT) */
 		HandleZoomMessage(this, this->viewport, EVW_ZOOMIN, EVW_ZOOMOUT);
 	}
diff --git a/src/waypoint_gui.cpp b/src/waypoint_gui.cpp
index 23c9781e3..af126f3ae 100644
--- a/src/waypoint_gui.cpp
+++ b/src/waypoint_gui.cpp
@@ -114,8 +114,14 @@ public:
 		}
 	}
 
-	virtual void OnInvalidateData(int data)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		/* You can only change your own waypoints */
 		this->SetWidgetDisabledState(WAYPVW_RENAME, !this->wp->IsInUse() || (this->wp->owner != _local_company && this->wp->owner != OWNER_NONE));
 		/* Disable the widget for waypoints with no use */
diff --git a/src/window_gui.h b/src/window_gui.h
index 3254ee8c4..fc5ebeeda 100644
--- a/src/window_gui.h
+++ b/src/window_gui.h
@@ -651,9 +651,9 @@ public:
 	/**
 	 * Some data on this window has become invalid.
 	 * @param data information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
 	 */
-	virtual void OnInvalidateData(int data = 0) {}
-
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true) {}
 
 	/**
 	 * The user clicked some place on the map when a tile highlight mode