Add several NewGRF variables to vehicle image callback whitelist

Add vehicle flags to control cached image invalidation

Various refactorings

src/CMakeLists.txt

@@ -235,6 +235,7 @@ add_files(
     newgrf_airporttiles.h
     newgrf_animation_base.h
     newgrf_animation_type.h
+    newgrf_cache_check.h
     newgrf_callbacks.h
     newgrf_canal.cpp
     newgrf_canal.h

src/aircraft.h

@@ -67,6 +67,7 @@ int GetAircraftFlightLevel(T *v, bool takeoff = false);
 struct AircraftCache {
 	uint32 cached_max_range_sqr;   ///< Cached squared maximum range.
 	uint16 cached_max_range;       ///< Cached maximum range.
+	byte image_movement_state;     ///< Cached image aircraft movement state
 };
 
 /**

src/aircraft_cmd.cpp

@@ -1276,6 +1276,7 @@ static void HandleAircraftSmoke(Aircraft *v, bool mode)
 	if (v->state != FLYING && v->state != LANDING && v->breakdown_type == BREAKDOWN_AIRCRAFT_SPEED) {
 		v->vehstatus &= ~VS_AIRCRAFT_BROKEN;
 		v->breakdown_ctr = 0;
+		v->InvalidateImageCacheOfChain();
 		return;
 	}
 
@@ -1334,7 +1335,7 @@ TileIndex Aircraft::GetOrderStationLocation(StationID station)
 void Aircraft::MarkDirty()
 {
 	this->colourmap = PAL_NONE;
-	this->cur_image_valid_dir = INVALID_DIR;
+	this->InvalidateImageCache();
 	this->UpdateViewport(true, false);
 	if (this->subtype == AIR_HELICOPTER) {
 		Aircraft *rotor = this->Next()->Next();
@@ -2161,6 +2162,15 @@ bool Aircraft::Tick()
 		if (!AircraftEventHandler(this, i)) return false;
 	}
 
+	if (HasBit(this->vcache.cached_veh_flags, VCF_REDRAW_ON_SPEED_CHANGE)) {
+		extern byte MapAircraftMovementState(const Aircraft *v);
+		byte state = MapAircraftMovementState(this);
+		if (state != this->acache.image_movement_state) {
+			this->InvalidateImageCacheOfChain();
+			this->acache.image_movement_state = state;
+		}
+	}
+
 	return true;
 }
 

src/company_cmd.cpp

@@ -1045,7 +1045,10 @@ CommandCost CmdSetCompanyColour(TileIndex tile, DoCommandFlag flags, uint32 p1,
 
 		/* Company colour data is indirectly cached. */
 		for (Vehicle *v : Vehicle::Iterate()) {
-			if (v->owner == _current_company) v->InvalidateNewGRFCache();
+			if (v->owner == _current_company) {
+				v->InvalidateNewGRFCache();
+				v->InvalidateImageCache();
+			}
 		}
 
 		extern void UpdateObjectColours(const Company *c);

src/disaster_vehicle.cpp

@@ -204,7 +204,7 @@ void DisasterVehicle::UpdatePosition(int x, int y, int z)
 	this->z_pos = z;
 	this->tile = TileVirtXY(x, y);
 
-	this->cur_image_valid_dir = INVALID_DIR;
+	this->InvalidateImageCache();
 	this->UpdateImage();
 	this->UpdatePositionAndViewport();
 
@@ -218,7 +218,7 @@ void DisasterVehicle::UpdatePosition(int x, int y, int z)
 		safe_y = Clamp(u->y_pos, 0, MapMaxY() * TILE_SIZE);
 		u->z_pos = GetSlopePixelZ(safe_x, safe_y);
 		u->direction = this->direction;
-		u->cur_image_valid_dir = INVALID_DIR;
+		u->InvalidateImageCache();
 
 		u->UpdateImage();
 		u->UpdatePositionAndViewport();

src/economy.cpp

@@ -466,6 +466,7 @@ void ChangeOwnershipOfCompanyItems(Owner old_owner, Owner new_owner)
 				/* Owner changes, clear cache */
 				v->colourmap = PAL_NONE;
 				v->InvalidateNewGRFCache();
+				v->InvalidateImageCache();
 
 				if (v->IsEngineCountable()) {
 					GroupStatistics::CountEngine(v, 1);

src/ground_vehicle.cpp

@@ -108,7 +108,7 @@ void GroundVehicle<T, Type>::CargoChanged()
 		weight += current_weight;
 		/* Slope steepness is in percent, result in N. */
 		u->gcache.cached_slope_resistance = current_weight * u->GetSlopeSteepness() * 100;
-		u->cur_image_valid_dir = INVALID_DIR;
+		u->InvalidateImageCache();
 	}
 	ClrBit(this->vcache.cached_veh_flags, VCF_GV_ZERO_SLOPE_RESIST);
 

src/ground_vehicle.hpp

@@ -398,6 +398,9 @@ struct GroundVehicle : public SpecializedVehicle<T, Type> {
 		if (this->cur_speed != this->gcache.last_speed) {
 			SetWindowWidgetDirty(WC_VEHICLE_VIEW, this->index, WID_VV_START_STOP);
 			this->gcache.last_speed = this->cur_speed;
+			if (HasBit(this->vcache.cached_veh_flags, VCF_REDRAW_ON_SPEED_CHANGE)) {
+				this->InvalidateImageCacheOfChain();
+			}
 		}
 	}
 

src/group_cmd.cpp

@@ -278,6 +278,7 @@ void PropagateChildLivery(const Group *g)
 			for (Vehicle *u = v; u != nullptr; u = u->Next()) {
 				u->colourmap = PAL_NONE;
 				u->InvalidateNewGRFCache();
+				u->InvalidateImageCache();
 			}
 		}
 	}
@@ -544,6 +545,7 @@ static void AddVehicleToGroup(Vehicle *v, GroupID new_g)
 			for (Vehicle *u = v; u != nullptr; u = u->Next()) {
 				u->colourmap = PAL_NONE;
 				u->InvalidateNewGRFCache();
+				u->InvalidateImageCache();
 				u->UpdateViewport(true);
 			}
 			break;
@@ -794,6 +796,7 @@ void SetTrainGroupID(Train *v, GroupID new_g)
 		u->group_id = new_g;
 		u->colourmap = PAL_NONE;
 		u->InvalidateNewGRFCache();
+		u->InvalidateImageCache();
 		u->UpdateViewport(true);
 	}
 
@@ -821,6 +824,7 @@ void UpdateTrainGroupID(Train *v)
 		u->group_id = new_g;
 		u->colourmap = PAL_NONE;
 		u->InvalidateNewGRFCache();
+		u->InvalidateImageCache();
 	}
 
 	/* Update the Replace Vehicle Windows */

src/newgrf.cpp

@@ -6354,6 +6354,19 @@ static void SkipAct5(ByteReader *buf)
  */
 bool GetGlobalVariable(byte param, uint32 *value, const GRFFile *grffile)
 {
+	if (_sprite_group_resolve_check_veh_check) {
+		switch (param) {
+			case 0x00:
+			case 0x02:
+			case 0x09:
+			case 0x0A:
+			case 0x20:
+			case 0x23:
+				_sprite_group_resolve_check_veh_check = false;
+				break;
+		}
+	}
+
 	switch (param) {
 		case 0x00: // current date
 			*value = max(_date - DAYS_TILL_ORIGINAL_BASE_YEAR, 0);

src/newgrf_airport.cpp

@@ -38,7 +38,7 @@ struct AirportScopeResolver : public ScopeResolver {
 	}
 
 	uint32 GetRandomBits() const override;
-	uint32 GetVariable(byte variable, uint32 parameter, bool *available) const override;
+	uint32 GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const override;
 	void StorePSA(uint pos, int32 value) override;
 };
 
@@ -197,14 +197,14 @@ void AirportOverrideManager::SetEntitySpec(AirportSpec *as)
 	}
 }
 
-/* virtual */ uint32 AirportScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
+/* virtual */ uint32 AirportScopeResolver::GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const
 {
 	switch (variable) {
 		case 0x40: return this->layout;
 	}
 
 	if (this->st == nullptr) {
-		*available = false;
+		extra->available = false;
 		return UINT_MAX;
 	}
 
@@ -216,7 +216,7 @@ void AirportOverrideManager::SetEntitySpec(AirportSpec *as)
 		case 0xFA: return Clamp(this->st->build_date - DAYS_TILL_ORIGINAL_BASE_YEAR, 0, 65535);
 	}
 
-	return this->st->GetNewGRFVariable(this->ro, variable, parameter, available);
+	return this->st->GetNewGRFVariable(this->ro, variable, parameter, &(extra->available));
 }
 
 /* virtual */ const SpriteGroup *AirportResolverObject::ResolveReal(const RealSpriteGroup *group) const

src/newgrf_airporttiles.cpp

@@ -158,7 +158,7 @@ static uint32 GetAirportTileIDAtOffset(TileIndex tile, const Station *st, uint32
 	return 0xFF << 8 | ats->grf_prop.subst_id; // so just give him the substitute
 }
 
-/* virtual */ uint32 AirportTileScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
+/* virtual */ uint32 AirportTileScopeResolver::GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const
 {
 	assert(this->st != nullptr);
 
@@ -195,7 +195,7 @@ static uint32 GetAirportTileIDAtOffset(TileIndex tile, const Station *st, uint32
 
 	DEBUG(grf, 1, "Unhandled airport tile variable 0x%X", variable);
 
-	*available = false;
+	extra->available = false;
 	return UINT_MAX;
 }
 

src/newgrf_airporttiles.h

@@ -38,7 +38,7 @@ struct AirportTileScopeResolver : public ScopeResolver {
 	}
 
 	uint32 GetRandomBits() const override;
-	uint32 GetVariable(byte variable, uint32 parameter, bool *available) const override;
+	uint32 GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const override;
 };
 
 /** Resolver for tiles of an airport. */

src/newgrf_cache_check.h

@@ -0,0 +1,15 @@
+/*
+ * This file is part of OpenTTD.
+ * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
+ * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/** @file newgrf_cache_check.h NewGRF caching checks. */
+
+#ifndef NEWGRF_CACHE_CHECK_H
+#define NEWGRF_CACHE_CHECK_H
+
+extern bool _sprite_group_resolve_check_veh_check;
+
+#endif /* NEWGRF_CACHE_CHECK_H */

src/newgrf_canal.cpp

@@ -30,7 +30,7 @@ struct CanalScopeResolver : public ScopeResolver {
 	}
 
 	uint32 GetRandomBits() const override;
-	uint32 GetVariable(byte variable, uint32 parameter, bool *available) const override;
+	uint32 GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const override;
 };
 
 /** Resolver object for canals. */
@@ -61,7 +61,7 @@ struct CanalResolverObject : public ResolverObject {
 	return IsTileType(this->tile, MP_WATER) ? GetWaterTileRandomBits(this->tile) : 0;
 }
 
-/* virtual */ uint32 CanalScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
+/* virtual */ uint32 CanalScopeResolver::GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const
 {
 	switch (variable) {
 		/* Height of tile */
@@ -104,7 +104,7 @@ struct CanalResolverObject : public ResolverObject {
 
 	DEBUG(grf, 1, "Unhandled canal variable 0x%02X", variable);
 
-	*available = false;
+	extra->available = false;
 	return UINT_MAX;
 }
 

src/newgrf_debug_gui.cpp

@@ -167,7 +167,7 @@ public:
 	 * @param avail Return whether the variable is available.
 	 * @return The resolved variable's value.
 	 */
-	virtual uint Resolve(uint index, uint var, uint param, bool *avail) const = 0;
+	virtual uint Resolve(uint index, uint var, uint param, GetVariableExtra *extra) const = 0;
 
 	/**
 	 * Used to decide if the PSA needs a parameter or not.
@@ -492,11 +492,11 @@ struct NewGRFInspectWindow : Window {
 		if (nif->variables != nullptr) {
 			this->DrawString(r, i++, "Variables:");
 			for (const NIVariable *niv = nif->variables; niv->name != nullptr; niv++) {
-				bool avail = true;
+				GetVariableExtra extra;
 				uint param = HasVariableParameter(niv->var) ? NewGRFInspectWindow::var60params[GetFeatureNum(this->window_number)][niv->var - 0x60] : 0;
-				uint value = nih->Resolve(index, niv->var, param, &avail);
+				uint value = nih->Resolve(index, niv->var, param, &extra);
 
-				if (!avail) continue;
+				if (!extra.available) continue;
 
 				if (HasVariableParameter(niv->var)) {
 					this->DrawString(r, i++, "  %02x[%02x]: %08x (%s)", niv->var, param, value, niv->name);

src/newgrf_engine.cpp

@@ -22,10 +22,13 @@
 #include "company_base.h"
 #include "newgrf_railtype.h"
 #include "newgrf_roadtype.h"
+#include "newgrf_cache_check.h"
 #include "ship.h"
 
 #include "safeguards.h"
 
+bool _sprite_group_resolve_check_veh_check = false;
+
 struct WagonOverride {
 	EngineID *train_id;
 	uint trains;
@@ -162,7 +165,7 @@ enum TTDPAircraftMovementStates {
  * Map OTTD aircraft movement states to TTDPatch style movement states
  * (VarAction 2 Variable 0xE2)
  */
-static byte MapAircraftMovementState(const Aircraft *v)
+byte MapAircraftMovementState(const Aircraft *v)
 {
 	const Station *st = GetTargetAirportIfValid(v);
 	if (st == nullptr) return AMS_TTDP_FLIGHT_TO_TOWER;
@@ -343,6 +346,14 @@ static byte MapAircraftMovementAction(const Aircraft *v)
 
 /* virtual */ uint32 VehicleScopeResolver::GetTriggers() const
 {
+	if (this->v == nullptr) {
+		return 0;
+	} else {
+		if (_sprite_group_resolve_check_veh_check) {
+			SetBit(const_cast<Vehicle*>(this->v->First())->vcache.cached_veh_flags, VCF_REDRAW_ON_TRIGGER);
+		}
+		return this->v->waiting_triggers;
+	}
 	return this->v == nullptr ? 0 : this->v->waiting_triggers;
 }
 
@@ -444,8 +455,118 @@ static uint32 PositionHelper(const Vehicle *v, bool consecutive)
 	return chain_before | chain_after << 8 | (chain_before + chain_after + consecutive) << 16;
 }
 
-static uint32 VehicleGetVariable(Vehicle *v, const VehicleScopeResolver *object, byte variable, uint32 parameter, bool *available)
+static uint32 VehicleGetVariable(Vehicle *v, const VehicleScopeResolver *object, byte variable, uint32 parameter, GetVariableExtra *extra)
 {
+	if (_sprite_group_resolve_check_veh_check) {
+		switch (variable) {
+			case 0xC:
+			case 0x10:
+			case 0x18:
+			case 0x1A:
+			case 0x1C:
+			case 0x25:
+			case 0x40:
+			case 0x41:
+			case 0x42:
+			case 0x43:
+			case 0x47:
+			case 0x48:
+			case 0x49:
+			case 0x4A:
+			case 0x4B:
+			case 0x4D:
+			case 0x60:
+			case 0x61:
+			case 0x7D:
+			case 0x7F:
+			case 0x80 + 0x0:
+			case 0x80 + 0x1:
+			case 0x80 + 0x4:
+			case 0x80 + 0x5:
+			case 0x80 + 0xA: // dubious
+			case 0x80 + 0xB: // dubious
+			case 0x80 + 0x39:
+			case 0x80 + 0x3A:
+			case 0x80 + 0x3B:
+			case 0x80 + 0x3C:
+			case 0x80 + 0x3D:
+			case 0x80 + 0x44:
+			case 0x80 + 0x45:
+			case 0x80 + 0x46:
+			case 0x80 + 0x47:
+			case 0x80 + 0x5A:
+			case 0x80 + 0x72:
+			case 0x80 + 0x7A:
+			case 0xFF:
+				break;
+
+			case 0x80 + 0x32:
+				if (extra->mask & (VS_HIDDEN | VS_TRAIN_SLOWING)) {
+					_sprite_group_resolve_check_veh_check = false;
+				}
+				break;
+
+			case 0x80 + 0x34:
+			case 0x80 + 0x35:
+				if (v->type == VEH_AIRCRAFT) {
+					_sprite_group_resolve_check_veh_check = false;
+				} else {
+					SetBit(v->First()->vcache.cached_veh_flags, VCF_REDRAW_ON_SPEED_CHANGE);
+				}
+				break;
+
+			case 0x5F:
+			case 0x80 + 0x7B:
+				SetBit(v->First()->vcache.cached_veh_flags, VCF_REDRAW_ON_TRIGGER);
+				break;
+
+			case 0x80 + 0x48:
+				// VRF_REVERSE_DIRECTION
+				if (v->type != VEH_TRAIN) {
+					_sprite_group_resolve_check_veh_check = false;
+				}
+				break;
+
+			case 0x80 + 0x62:
+				switch (v->type) {
+					case VEH_TRAIN:
+					case VEH_SHIP:
+						if (extra->mask & 0x7F) {
+							_sprite_group_resolve_check_veh_check = false;
+						}
+						break;
+
+					case VEH_ROAD:
+						break;
+
+					case VEH_AIRCRAFT:
+						if (v == v->First()) {
+							SetBit(v->First()->vcache.cached_veh_flags, VCF_REDRAW_ON_SPEED_CHANGE);
+						} else {
+							_sprite_group_resolve_check_veh_check = false;
+						}
+						break;
+
+					default:
+						_sprite_group_resolve_check_veh_check = false;
+						break;
+				}
+				break;
+
+			case 0xFE:
+				// vehicle is unloading, VF_CARGO_UNLOADING may disappear without the vehicle being marked dirty
+				// the vehicle is always marked dirty when VF_CARGO_UNLOADING is set
+				if (HasBit(v->vehicle_flags, VF_CARGO_UNLOADING)) {
+					_sprite_group_resolve_check_veh_check = false;
+				}
+				break;
+
+			default:
+				_sprite_group_resolve_check_veh_check = false;
+				break;
+		}
+	}
+
 	/* Calculated vehicle parameters */
 	switch (variable) {
 		case 0x25: // Get engine GRF ID
@@ -667,9 +788,12 @@ static uint32 VehicleGetVariable(Vehicle *v, const VehicleScopeResolver *object,
 
 				if (parameter == 0x5F) {
 					/* This seems to be the only variable that makes sense to access via var 61, but is not handled by VehicleGetVariable */
+					if (_sprite_group_resolve_check_veh_check) {
+						SetBit(u->First()->vcache.cached_veh_flags, VCF_REDRAW_ON_TRIGGER);
+					}
 					return (u->random_bits << 8) | u->waiting_triggers;
 				} else {
-					return VehicleGetVariable(u, object, parameter, GetRegister(0x10E), available);
+					return VehicleGetVariable(u, object, parameter, GetRegister(0x10E), extra);
 				}
 			}
 			/* Not available */
@@ -891,11 +1015,11 @@ static uint32 VehicleGetVariable(Vehicle *v, const VehicleScopeResolver *object,
 
 	DEBUG(grf, 1, "Unhandled vehicle variable 0x%X, type 0x%X", variable, (uint)v->type);
 
-	*available = false;
+	extra->available = false;
 	return UINT_MAX;
 }
 
-/* virtual */ uint32 VehicleScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
+/* virtual */ uint32 VehicleScopeResolver::GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const
 {
 	if (this->v == nullptr) {
 		/* Vehicle does not exist, so we're in a purchase list */
@@ -922,11 +1046,11 @@ static uint32 VehicleGetVariable(Vehicle *v, const VehicleScopeResolver *object,
 			case 0xF2: return 0; // Cargo subtype
 		}
 
-		*available = false;
+		extra->available = false;
 		return UINT_MAX;
 	}
 
-	return VehicleGetVariable(const_cast<Vehicle*>(this->v), this, variable, parameter, available);
+	return VehicleGetVariable(const_cast<Vehicle*>(this->v), this, variable, parameter, extra);
 }
 
 
@@ -1206,6 +1330,9 @@ void TriggerVehicle(Vehicle *v, VehicleTrigger trigger)
 
 	v->InvalidateNewGRFCacheOfChain();
 	DoTriggerVehicle(v, trigger, 0, true);
+	if (HasBit(v->First()->vcache.cached_veh_flags, VCF_REDRAW_ON_TRIGGER)) {
+		v->First()->InvalidateImageCacheOfChain();
+	}
 	v->InvalidateNewGRFCacheOfChain();
 }
 
@@ -1325,8 +1452,8 @@ void FillNewGRFVehicleCache(const Vehicle *v)
 	for (size_t i = 0; i < lengthof(cache_entries); i++) {
 		/* Only resolve when the cache isn't valid. */
 		if (HasBit(v->grf_cache.cache_valid, cache_entries[i][1])) continue;
-		bool stub;
+		GetVariableExtra extra;
-		ro.GetScope(VSG_SCOPE_SELF)->GetVariable(cache_entries[i][0], 0, &stub);
+		ro.GetScope(VSG_SCOPE_SELF)->GetVariable(cache_entries[i][0], 0, &extra);
 	}
 
 	/* Make sure really all bits are set. */

src/newgrf_engine.h

@@ -39,7 +39,7 @@ struct VehicleScopeResolver : public ScopeResolver {
 	void SetVehicle(const Vehicle *v) { this->v = v; }
 
 	uint32 GetRandomBits() const override;
-	uint32 GetVariable(byte variable, uint32 parameter, bool *available) const override;
+	uint32 GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const override;
 	uint32 GetTriggers() const override;
 };
 

src/newgrf_generic.cpp

@@ -42,7 +42,7 @@ struct GenericScopeResolver : public ScopeResolver {
 	{
 	}
 
-	uint32 GetVariable(byte variable, uint32 parameter, bool *available) const override;
+	uint32 GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const override;
 
 private:
 	bool ai_callback; ///< Callback comes from the AI.
@@ -121,7 +121,7 @@ void AddGenericCallback(uint8 feature, const GRFFile *file, const SpriteGroup *g
 	_gcl[feature].push_front(GenericCallback(file, group));
 }
 
-/* virtual */ uint32 GenericScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
+/* virtual */ uint32 GenericScopeResolver::GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const
 {
 	if (this->ai_callback) {
 		switch (variable) {
@@ -143,7 +143,7 @@ void AddGenericCallback(uint8 feature, const GRFFile *file, const SpriteGroup *g
 
 	DEBUG(grf, 1, "Unhandled generic feature variable 0x%02X", variable);
 
-	*available = false;
+	extra->available = false;
 	return UINT_MAX;
 }
 

src/newgrf_house.cpp

@@ -322,7 +322,7 @@ static uint32 GetDistanceFromNearbyHouse(uint8 parameter, TileIndex tile, HouseI
 /**
  * @note Used by the resolver to get values for feature 07 deterministic spritegroups.
  */
-/* virtual */ uint32 HouseScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
+/* virtual */ uint32 HouseScopeResolver::GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const
 {
 	switch (variable) {
 		/* Construction stage. */
@@ -438,7 +438,7 @@ static uint32 GetDistanceFromNearbyHouse(uint8 parameter, TileIndex tile, HouseI
 
 	DEBUG(grf, 1, "Unhandled house variable 0x%X", variable);
 
-	*available = false;
+	extra->available = false;
 	return UINT_MAX;
 }
 
@@ -446,7 +446,7 @@ static uint32 GetDistanceFromNearbyHouse(uint8 parameter, TileIndex tile, HouseI
 /**
  * @note Used by the resolver to get values for feature 07 deterministic spritegroups.
  */
-/* virtual */ uint32 FakeHouseScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
+/* virtual */ uint32 FakeHouseScopeResolver::GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const
 {
 	switch (variable) {
 		/* Construction stage. */
@@ -500,7 +500,7 @@ static uint32 GetDistanceFromNearbyHouse(uint8 parameter, TileIndex tile, HouseI
 
 	DEBUG(grf, 1, "Unhandled house variable 0x%X", variable);
 
-	*available = false;
+	extra->available = false;
 	return UINT_MAX;
 }
 

src/newgrf_house.h

@@ -50,7 +50,7 @@ struct HouseScopeResolver : public CommonHouseScopeResolver {
 	}
 
 	uint32 GetRandomBits() const override;
-	uint32 GetVariable(byte variable, uint32 parameter, bool *available) const override;
+	uint32 GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const override;
 	uint32 GetTriggers() const override;
 };
 
@@ -70,7 +70,7 @@ struct FakeHouseScopeResolver : public CommonHouseScopeResolver {
 		: CommonHouseScopeResolver(ro, house_id)
 	{ }
 
-	/* virtual */ uint32 GetVariable(byte variable, uint32 parameter, bool *available) const;
+	/* virtual */ uint32 GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const;
 };
 
 /** Resolver object to be used for houses (feature 07 spritegroups). */

src/newgrf_industries.cpp

@@ -155,7 +155,7 @@ static uint32 GetCountAndDistanceOfClosestInstance(byte param_setID, byte layout
 	return count << 16 | GB(closest_dist, 0, 16);
 }
 
-/* virtual */ uint32 IndustriesScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
+/* virtual */ uint32 IndustriesScopeResolver::GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const
 {
 	if (this->ro.callback == CBID_INDUSTRY_LOCATION) {
 		/* Variables available during construction check. */
@@ -201,7 +201,7 @@ static uint32 GetCountAndDistanceOfClosestInstance(byte param_setID, byte layout
 	if (this->industry == nullptr) {
 		DEBUG(grf, 1, "Unhandled variable 0x%X (no available industry) in callback 0x%x", variable, this->ro.callback);
 
-		*available = false;
+		extra->available = false;
 		return UINT_MAX;
 	}
 
@@ -401,7 +401,7 @@ static uint32 GetCountAndDistanceOfClosestInstance(byte param_setID, byte layout
 
 	DEBUG(grf, 1, "Unhandled industry variable 0x%X", variable);
 
-	*available = false;
+	extra->available = false;
 	return UINT_MAX;
 }
 

src/newgrf_industries.h

@@ -33,7 +33,7 @@ struct IndustriesScopeResolver : public ScopeResolver {
 	}
 
 	uint32 GetRandomBits() const override;
-	uint32 GetVariable(byte variable, uint32 parameter, bool *available) const override;
+	uint32 GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const override;
 	uint32 GetTriggers() const override;
 	void StorePSA(uint pos, int32 value) override;
 };

src/newgrf_industrytiles.cpp

@@ -58,7 +58,7 @@ uint32 GetRelativePosition(TileIndex tile, TileIndex ind_tile)
 	return ((y & 0xF) << 20) | ((x & 0xF) << 16) | (y << 8) | x;
 }
 
-/* virtual */ uint32 IndustryTileScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
+/* virtual */ uint32 IndustryTileScopeResolver::GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const
 {
 	switch (variable) {
 		/* Construction state of the tile: a value between 0 and 3 */
@@ -95,7 +95,7 @@ uint32 GetRelativePosition(TileIndex tile, TileIndex ind_tile)
 
 	DEBUG(grf, 1, "Unhandled industry tile variable 0x%X", variable);
 
-	*available = false;
+	extra->available = false;
 	return UINT_MAX;
 }
 

src/newgrf_industrytiles.h

@@ -31,7 +31,7 @@ struct IndustryTileScopeResolver : public ScopeResolver {
 	}
 
 	uint32 GetRandomBits() const override;
-	uint32 GetVariable(byte variable, uint32 parameter, bool *available) const override;
+	uint32 GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const override;
 	uint32 GetTriggers() const override;
 };
 

src/newgrf_object.cpp

@@ -230,7 +230,7 @@ static uint32 GetCountAndDistanceOfClosestInstance(byte local_id, uint32 grfid,
 }
 
 /** Used by the resolver to get values for feature 0F deterministic spritegroups. */
-/* virtual */ uint32 ObjectScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
+/* virtual */ uint32 ObjectScopeResolver::GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const
 {
 	/* We get the town from the object, or we calculate the closest
 	 * town if we need to when there's no object. */
@@ -337,7 +337,7 @@ static uint32 GetCountAndDistanceOfClosestInstance(byte local_id, uint32 grfid,
 unhandled:
 	DEBUG(grf, 1, "Unhandled object variable 0x%X", variable);
 
-	*available = false;
+	extra->available = false;
 	return UINT_MAX;
 }
 

src/newgrf_object.h

@@ -116,7 +116,7 @@ struct ObjectScopeResolver : public ScopeResolver {
 	}
 
 	uint32 GetRandomBits() const override;
-	uint32 GetVariable(byte variable, uint32 parameter, bool *available) const override;
+	uint32 GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const override;
 };
 
 /** A resolver object to be used with feature 0F spritegroups. */

src/newgrf_railtype.cpp

@@ -22,7 +22,7 @@
 	return GB(tmp, 0, 2);
 }
 
-/* virtual */ uint32 RailTypeScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
+/* virtual */ uint32 RailTypeScopeResolver::GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const
 {
 	if (this->tile == INVALID_TILE) {
 		switch (variable) {
@@ -54,7 +54,7 @@
 
 	DEBUG(grf, 1, "Unhandled rail type tile variable 0x%X", variable);
 
-	*available = false;
+	extra->available = false;
 	return UINT_MAX;
 }
 

src/newgrf_railtype.h

@@ -32,7 +32,7 @@ struct RailTypeScopeResolver : public ScopeResolver {
 	}
 
 	uint32 GetRandomBits() const override;
-	uint32 GetVariable(byte variable, uint32 parameter, bool *available) const override;
+	uint32 GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const override;
 };
 
 /** Resolver object for rail types. */

src/newgrf_roadtype.cpp

@@ -22,7 +22,7 @@
 	return GB(tmp, 0, 2);
 }
 
-/* virtual */ uint32 RoadTypeScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
+/* virtual */ uint32 RoadTypeScopeResolver::GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const
 {
 	if (this->tile == INVALID_TILE) {
 		switch (variable) {
@@ -54,7 +54,7 @@
 
 	DEBUG(grf, 1, "Unhandled road type tile variable 0x%X", variable);
 
-	*available = false;
+	extra->available = false;
 	return UINT_MAX;
 }
 

src/newgrf_roadtype.h

@@ -23,7 +23,7 @@ struct RoadTypeScopeResolver : public ScopeResolver {
 	RoadTypeScopeResolver(ResolverObject &ro, const RoadTypeInfo *rti, TileIndex tile, TileContext context);
 
 	/* virtual */ uint32 GetRandomBits() const;
-	/* virtual */ uint32 GetVariable(byte variable, uint32 parameter, bool *available) const;
+	/* virtual */ uint32 GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const;
 };
 
 /** Resolver object for road types. */

src/newgrf_spritegroup.cpp

@@ -14,6 +14,8 @@
 #include "newgrf_profiling.h"
 #include "core/pool_func.hpp"
 #include "vehicle_type.h"
+#include "newgrf_cache_check.h"
+#include "scope_info.h"
 
 #include "safeguards.h"
 
@@ -72,7 +74,7 @@ RandomizedSpriteGroup::~RandomizedSpriteGroup()
 	free(this->groups);
 }
 
-static inline uint32 GetVariable(const ResolverObject &object, ScopeResolver *scope, byte variable, uint32 parameter, bool *available)
+static inline uint32 GetVariable(const ResolverObject &object, ScopeResolver *scope, byte variable, uint32 parameter, GetVariableExtra *extra)
 {
 	uint32 value;
 	switch (variable) {
@@ -93,7 +95,7 @@ static inline uint32 GetVariable(const ResolverObject &object, ScopeResolver *sc
 			/* First handle variables common with Action7/9/D */
 			if (variable < 0x40 && GetGlobalVariable(variable, &value, object.grffile)) return value;
 			/* Not a common variable, so evaluate the feature specific variables */
-			return scope->GetVariable(variable, parameter, available);
+			return scope->GetVariable(variable, parameter, extra);
 	}
 }
 
@@ -122,10 +124,10 @@ static inline uint32 GetVariable(const ResolverObject &object, ScopeResolver *sc
  * @param[out] available Set to false, in case the variable does not exist.
  * @return Value
  */
-/* virtual */ uint32 ScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
+/* virtual */ uint32 ScopeResolver::GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const
 {
 	DEBUG(grf, 1, "Unhandled scope variable 0x%X", variable);
-	*available = false;
+	extra->available = false;
 	return UINT_MAX;
 }
 
@@ -199,9 +201,6 @@ static U EvalAdjustT(const DeterministicSpriteGroupAdjust *adjust, ScopeResolver
 	}
 }
 
-bool _sprite_group_resolve_check_veh_check = false;
-VehicleType _sprite_group_resolve_check_veh_type;
-
 static bool RangeHighComparator(const DeterministicSpriteGroupRange& range, uint32 value)
 {
 	return range.high < value;
@@ -219,9 +218,8 @@ const SpriteGroup *DeterministicSpriteGroup::Resolve(ResolverObject &object) con
 		DeterministicSpriteGroupAdjust *adjust = &this->adjusts[i];
 
 		/* Try to get the variable. We shall assume it is available, unless told otherwise. */
-		bool available = true;
+		GetVariableExtra extra(adjust->and_mask << adjust->shift_num);
 		if (adjust->variable == 0x7E) {
-			_sprite_group_resolve_check_veh_check = false;
 			const SpriteGroup *subgroup = SpriteGroup::Resolve(adjust->subroutine, object, false);
 			if (subgroup == nullptr) {
 				value = CALLBACK_FAILED;
@@ -232,59 +230,12 @@ const SpriteGroup *DeterministicSpriteGroup::Resolve(ResolverObject &object) con
 			/* Note: 'last_value' and 'reseed' are shared between the main chain and the procedure */
 		} else if (adjust->variable == 0x7B) {
 			_sprite_group_resolve_check_veh_check = false;
-			value = GetVariable(object, scope, adjust->parameter, last_value, &available);
+			value = GetVariable(object, scope, adjust->parameter, last_value, &extra);
 		} else {
-			if (_sprite_group_resolve_check_veh_check) {
+			value = GetVariable(object, scope, adjust->variable, adjust->parameter, &extra);
-				switch (adjust->variable) {
-					// whitelist of variables which can be checked without requiring an immediate re-check on the next tick
-					case 0xC:
-					case 0x1A:
-					case 0x1C:
-					case 0x25:
-					case 0x40:
-					case 0x41:
-					case 0x42:
-					case 0x47:
-					case 0x49:
-					case 0x4B:
-					case 0x4D:
-					case 0x60:
-					case 0x7D:
-					case 0x7F:
-					case 0x80 + 0x0:
-					case 0x80 + 0x1:
-					case 0x80 + 0x4:
-					case 0x80 + 0x5:
-					case 0x80 + 0x39:
-					case 0x80 + 0x3A:
-					case 0x80 + 0x3B:
-					case 0x80 + 0x3C:
-					case 0x80 + 0x3D:
-					case 0x80 + 0x44:
-					case 0x80 + 0x45:
-					case 0x80 + 0x46:
-					case 0x80 + 0x47:
-					case 0x80 + 0x5A:
-					case 0x80 + 0x72:
-					case 0x80 + 0x7A:
-						break;
-
-					case 0x80 + 0x62:
-						// RoadVehicle::state
-						if (_sprite_group_resolve_check_veh_type != VEH_ROAD) {
-							_sprite_group_resolve_check_veh_check = false;
-						}
-						break;
-
-					default:
-						_sprite_group_resolve_check_veh_check = false;
-						break;
-				}
-			}
-			value = GetVariable(object, scope, adjust->variable, adjust->parameter, &available);
 		}
 
-		if (!available) {
+		if (!extra.available) {
 			/* Unsupported variable: skip further processing and return either
 			 * the group from the first range or the default group. */
 			return SpriteGroup::Resolve(this->error_group, object, false);

src/newgrf_spritegroup.h

@@ -287,6 +287,14 @@ struct IndustryProductionSpriteGroup : SpriteGroup {
 
 };
 
+struct GetVariableExtra {
+	bool available;
+	uint32 mask;
+
+	GetVariableExtra(uint32 mask_ = 0xFFFFFFFF)
+			: available(true), mask(mask_) {}
+};
+
 /**
  * Interface to query and set values specific to a single #VarSpriteGroupScope (action 2 scope).
  *
@@ -302,7 +310,7 @@ struct ScopeResolver {
 	virtual uint32 GetRandomBits() const;
 	virtual uint32 GetTriggers() const;
 
-	virtual uint32 GetVariable(byte variable, uint32 parameter, bool *available) const;
+	virtual uint32 GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const;
 	virtual void StorePSA(uint reg, int32 value);
 };
 

src/newgrf_station.cpp

@@ -268,7 +268,7 @@ TownScopeResolver *StationResolverObject::GetTown()
 	return this->town_scope;
 }
 
-/* virtual */ uint32 StationScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
+/* virtual */ uint32 StationScopeResolver::GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const
 {
 	if (this->st == nullptr) {
 		/* Station does not exist, so we're in a purchase list or the land slope check callback. */
@@ -296,7 +296,7 @@ TownScopeResolver *StationResolverObject::GetTown()
 			case 0xFA: return Clamp(_date - DAYS_TILL_ORIGINAL_BASE_YEAR, 0, 65535); // Build date, clamped to a 16 bit value
 		}
 
-		*available = false;
+		extra->available = false;
 		return UINT_MAX;
 	}
 
@@ -386,7 +386,7 @@ TownScopeResolver *StationResolverObject::GetTown()
 		case 0xFA: return Clamp(this->st->build_date - DAYS_TILL_ORIGINAL_BASE_YEAR, 0, 65535);
 	}
 
-	return this->st->GetNewGRFVariable(this->ro, variable, parameter, available);
+	return this->st->GetNewGRFVariable(this->ro, variable, parameter, &(extra->available));
 }
 
 uint32 Station::GetNewGRFVariable(const ResolverObject &object, byte variable, byte parameter, bool *available) const

src/newgrf_station.h

@@ -45,7 +45,7 @@ struct StationScopeResolver : public ScopeResolver {
 	uint32 GetRandomBits() const override;
 	uint32 GetTriggers() const override;
 
-	uint32 GetVariable(byte variable, uint32 parameter, bool *available) const override;
+	uint32 GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const override;
 };
 
 /** Station resolver. */

src/newgrf_town.cpp

@@ -14,7 +14,7 @@
 
 #include "safeguards.h"
 
-/* virtual */ uint32 TownScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
+/* virtual */ uint32 TownScopeResolver::GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const
 {
 	switch (variable) {
 		/* Larger towns */
@@ -113,7 +113,7 @@
 
 	DEBUG(grf, 1, "Unhandled town variable 0x%X", variable);
 
-	*available = false;
+	extra->available = false;
 	return UINT_MAX;
 }
 
@@ -148,7 +148,7 @@
 	t->psa_list.push_back(psa);
 }
 
-/* virtual */ uint32 FakeTownScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
+/* virtual */ uint32 FakeTownScopeResolver::GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const
 {
 	switch (variable) {
 		/* Town index */
@@ -168,7 +168,7 @@
 
 	DEBUG(grf, 1, "Unhandled town variable 0x%X", variable);
 
-	*available = false;
+	extra->available = false;
 	return UINT_MAX;
 }
 

src/newgrf_town.h

@@ -34,7 +34,7 @@ struct TownScopeResolver : public ScopeResolver {
 	{
 	}
 
-	virtual uint32 GetVariable(byte variable, uint32 parameter, bool *available) const;
+	virtual uint32 GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const;
 	virtual void StorePSA(uint reg, int32 value);
 };
 
@@ -53,7 +53,7 @@ struct FakeTownScopeResolver : public ScopeResolver {
 	FakeTownScopeResolver(ResolverObject &ro) : ScopeResolver(ro)
 	{ }
 
-	virtual uint32 GetVariable(byte variable, uint32 parameter, bool *available) const;
+	virtual uint32 GetVariable(byte variable, uint32 parameter, GetVariableExtra *extra) const;
 };
 
 /** Resolver of town properties. */

src/road_cmd.cpp

@@ -2362,7 +2362,7 @@ static VehicleEnterTileStatus VehicleEnter_Road(Vehicle *v, TileIndex tile, int
 			RoadVehicle *rv = RoadVehicle::From(v);
 			if (rv->frame == RVC_DEPOT_STOP_FRAME &&
 					_roadveh_enter_depot_dir[GetRoadDepotDirection(tile)] == rv->state) {
-				rv->cur_image_valid_dir = INVALID_DIR;
+				rv->InvalidateImageCache();
 				rv->state = RVSB_IN_DEPOT;
 				rv->vehstatus |= VS_HIDDEN;
 				rv->direction = ReverseDir(rv->direction);

src/roadveh_cmd.cpp

@@ -415,7 +415,7 @@ void RoadVehicle::MarkDirty()
 {
 	for (RoadVehicle *v = this; v != nullptr; v = v->Next()) {
 		v->colourmap = PAL_NONE;
-		v->cur_image_valid_dir = INVALID_DIR;
+		v->InvalidateImageCache();
 		v->UpdateViewport(true, false);
 	}
 	this->CargoChanged();
@@ -1119,7 +1119,7 @@ static bool RoadVehLeaveDepot(RoadVehicle *v, bool first)
 	}
 
 	v->vehstatus &= ~VS_HIDDEN;
-	v->cur_image_valid_dir = INVALID_DIR;
+	v->InvalidateImageCache();
 	v->state = tdir;
 	v->frame = RVC_DEPOT_START_FRAME;
 	v->UpdateIsDrawn();
@@ -1437,7 +1437,7 @@ again:
 		}
 
 		if (!HasBit(r, VETS_ENTERED_WORMHOLE)) {
-			v->cur_image_valid_dir = INVALID_DIR;
+			v->InvalidateImageCache();
 			TileIndex old_tile = v->tile;
 
 			v->tile = tile;
@@ -1513,7 +1513,7 @@ again:
 			return false;
 		}
 
-		v->cur_image_valid_dir = INVALID_DIR;
+		v->InvalidateImageCache();
 		v->state = dir;
 		v->frame = turn_around_start_frame;
 

src/ship_cmd.cpp

@@ -277,7 +277,7 @@ Trackdir Ship::GetVehicleTrackdir() const
 void Ship::MarkDirty()
 {
 	this->colourmap = PAL_NONE;
-	this->cur_image_valid_dir = INVALID_DIR;
+	this->InvalidateImageCache();
 	this->UpdateViewport(true, false);
 	this->UpdateCache();
 }

src/table/newgrf_debug_data.h

@@ -78,11 +78,11 @@ class NIHVehicle : public NIHelper {
 	void SetStringParameters(uint index) const override  { this->SetSimpleStringParameters(STR_VEHICLE_NAME, index); }
 	uint32 GetGRFID(uint index) const override                   { return Vehicle::Get(index)->GetGRFID(); }
 
-	uint Resolve(uint index, uint var, uint param, bool *avail) const override
+	uint Resolve(uint index, uint var, uint param, GetVariableExtra *extra) const override
 	{
 		Vehicle *v = Vehicle::Get(index);
 		VehicleResolverObject ro(v->engine_type, v, VehicleResolverObject::WO_CACHED);
-		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, avail);
+		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, extra);
 	}
 
 	/* virtual */ void ExtraInfo(uint index, std::function<void(const char *)> print) const override
@@ -170,6 +170,9 @@ class NIHVehicle : public NIHelper {
 					e->duration_phase_1 + e->duration_phase_2 + e->duration_phase_3);
 			print(buffer);
 		}
+
+		seprintf(buffer, lastof(buffer), "  Current image cacheable: %s", v->cur_image_valid_dir != INVALID_DIR ? "yes" : "no");
+		print(buffer);
 	}
 };
 
@@ -229,10 +232,10 @@ class NIHStation : public NIHelper {
 	void SetStringParameters(uint index) const override  { this->SetObjectAtStringParameters(STR_STATION_NAME, GetStationIndex(index), index); }
 	uint32 GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? GetStationSpec(index)->grf_prop.grffile->grfid : 0; }
 
-	uint Resolve(uint index, uint var, uint param, bool *avail) const override
+	uint Resolve(uint index, uint var, uint param, GetVariableExtra *extra) const override
 	{
 		StationResolverObject ro(GetStationSpec(index), Station::GetByTile(index), index, INVALID_RAILTYPE);
-		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, avail);
+		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, extra);
 	}
 };
 
@@ -294,10 +297,10 @@ class NIHHouse : public NIHelper {
 	void SetStringParameters(uint index) const override  { this->SetObjectAtStringParameters(STR_TOWN_NAME, GetTownIndex(index), index); }
 	uint32 GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? HouseSpec::Get(GetHouseType(index))->grf_prop.grffile->grfid : 0; }
 
-	uint Resolve(uint index, uint var, uint param, bool *avail) const override
+	uint Resolve(uint index, uint var, uint param, GetVariableExtra *extra) const override
 	{
 		HouseResolverObject ro(GetHouseType(index), index, Town::GetByTile(index));
-		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, avail);
+		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, extra);
 	}
 
 	void ExtraInfo(uint index, std::function<void(const char *)> print) const override
@@ -359,10 +362,10 @@ class NIHIndustryTile : public NIHelper {
 	void SetStringParameters(uint index) const override  { this->SetObjectAtStringParameters(STR_INDUSTRY_NAME, GetIndustryIndex(index), index); }
 	uint32 GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? GetIndustryTileSpec(GetIndustryGfx(index))->grf_prop.grffile->grfid : 0; }
 
-	uint Resolve(uint index, uint var, uint param, bool *avail) const override
+	uint Resolve(uint index, uint var, uint param, GetVariableExtra *extra) const override
 	{
 		IndustryTileResolverObject ro(GetIndustryGfx(index), index, Industry::GetByTile(index));
-		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, avail);
+		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, extra);
 	}
 };
 
@@ -458,11 +461,11 @@ class NIHIndustry : public NIHelper {
 	void SetStringParameters(uint index) const override  { this->SetSimpleStringParameters(STR_INDUSTRY_NAME, index); }
 	uint32 GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? GetIndustrySpec(Industry::Get(index)->type)->grf_prop.grffile->grfid : 0; }
 
-	uint Resolve(uint index, uint var, uint param, bool *avail) const override
+	uint Resolve(uint index, uint var, uint param, GetVariableExtra *extra) const override
 	{
 		Industry *i = Industry::Get(index);
 		IndustriesResolverObject ro(i->location.tile, i, i->type);
-		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, avail);
+		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, extra);
 	}
 
 	uint GetPSASize(uint index, uint32 grfid) const override { return cpp_lengthof(PersistentStorage, storage); }
@@ -546,10 +549,10 @@ class NIHObject : public NIHelper {
 	void SetStringParameters(uint index) const override  { this->SetObjectAtStringParameters(STR_NEWGRF_INSPECT_CAPTION_OBJECT_AT_OBJECT, INVALID_STRING_ID, index); }
 	uint32 GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? ObjectSpec::GetByTile(index)->grf_prop.grffile->grfid : 0; }
 
-	uint Resolve(uint index, uint var, uint param, bool *avail) const override
+	uint Resolve(uint index, uint var, uint param, GetVariableExtra *extra) const override
 	{
 		ObjectResolverObject ro(ObjectSpec::GetByTile(index), Object::GetByTile(index), index);
-		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, avail);
+		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, extra);
 	}
 };
 
@@ -580,12 +583,12 @@ class NIHRailType : public NIHelper {
 	void SetStringParameters(uint index) const override  { this->SetObjectAtStringParameters(STR_NEWGRF_INSPECT_CAPTION_OBJECT_AT_RAIL_TYPE, INVALID_STRING_ID, index); }
 	uint32 GetGRFID(uint index) const override           { return 0; }
 
-	uint Resolve(uint index, uint var, uint param, bool *avail) const override
+	uint Resolve(uint index, uint var, uint param, GetVariableExtra *extra) const override
 	{
 		/* There is no unique GRFFile for the tile. Multiple GRFs can define different parts of the railtype.
 		 * However, currently the NewGRF Debug GUI does not display variables depending on the GRF (like 0x7F) anyway. */
 		RailTypeResolverObject ro(nullptr, index, TCX_NORMAL, RTSG_END);
-		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, avail);
+		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, extra);
 	}
 
 	void ExtraInfo(uint index, std::function<void(const char *)> print) const override
@@ -644,10 +647,10 @@ class NIHAirportTile : public NIHelper {
 	void SetStringParameters(uint index) const override  { this->SetObjectAtStringParameters(STR_STATION_NAME, GetStationIndex(index), index); }
 	uint32 GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? AirportTileSpec::Get(GetAirportGfx(index))->grf_prop.grffile->grfid : 0; }
 
-	uint Resolve(uint index, uint var, uint param, bool *avail) const override
+	uint Resolve(uint index, uint var, uint param, GetVariableExtra *extra) const override
 	{
 		AirportTileResolverObject ro(AirportTileSpec::GetByTile(index), index, Station::GetByTile(index));
-		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, avail);
+		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, extra);
 	}
 };
 
@@ -684,10 +687,10 @@ class NIHTown : public NIHelper {
 	bool PSAWithParameter() const override               { return true; }
 	uint GetPSASize(uint index, uint32 grfid) const override { return cpp_lengthof(PersistentStorage, storage); }
 
-	uint Resolve(uint index, uint var, uint param, bool *avail) const override
+	uint Resolve(uint index, uint var, uint param, GetVariableExtra *extra) const override
 	{
 		TownResolverObject ro(nullptr, Town::Get(index), true);
-		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, avail);
+		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, extra);
 	}
 
 	const int32 *GetPSAFirstPosition(uint index, uint32 grfid) const override
@@ -738,7 +741,7 @@ class NIHStationStruct : public NIHelper {
 	void SetStringParameters(uint index) const override  { this->SetSimpleStringParameters(STR_STATION_NAME, index); }
 	uint32 GetGRFID(uint index) const override           { return 0; }
 
-	uint Resolve(uint index, uint var, uint param, bool *avail) const override
+	uint Resolve(uint index, uint var, uint param, GetVariableExtra *extra) const override
 	{
 		return 0;
 	}
@@ -803,12 +806,12 @@ class NIHRoadType : public NIHelper {
 	void SetStringParameters(uint index) const override  { this->SetObjectAtStringParameters(STR_NEWGRF_INSPECT_CAPTION_OBJECT_AT_RAIL_TYPE, INVALID_STRING_ID, index); }
 	uint32 GetGRFID(uint index) const override           { return 0; }
 
-	uint Resolve(uint index, uint var, uint param, bool *avail) const override
+	uint Resolve(uint index, uint var, uint param, GetVariableExtra *extra) const override
 	{
 		/* There is no unique GRFFile for the tile. Multiple GRFs can define different parts of the railtype.
 		 * However, currently the NewGRF Debug GUI does not display variables depending on the GRF (like 0x7F) anyway. */
 		RoadTypeResolverObject ro(nullptr, index, TCX_NORMAL, ROTSG_END);
-		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, avail);
+		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, extra);
 	}
 };
 

src/train_cmd.cpp

@@ -1832,7 +1832,7 @@ static void SwapTrainFlags(uint16 *swap_flag1, uint16 *swap_flag2)
  */
 static void UpdateStatusAfterSwap(Train *v)
 {
-	v->cur_image_valid_dir = INVALID_DIR;
+	v->InvalidateImageCache();
 
 	/* Reverse the direction. */
 	if (v->track != TRACK_BIT_DEPOT) v->direction = ReverseDir(v->direction);
@@ -3418,7 +3418,7 @@ void Train::MarkDirty()
 	Train *v = this;
 	do {
 		v->colourmap = PAL_NONE;
-		v->cur_image_valid_dir = INVALID_DIR;
+		v->InvalidateImageCache();
 		v->UpdateViewport(true, false);
 	} while ((v = v->Next()) != nullptr);
 

src/tunnelbridge_cmd.cpp

@@ -2695,7 +2695,7 @@ static VehicleEnterTileStatus VehicleEnter_TunnelBridge(Vehicle *v, TileIndex ti
 					assert_msg(frame == rv->frame + 1 || rv->frame == _tunnel_turnaround_pre_visibility_frame[dir],
 							"frame: %u, rv->frame: %u, dir: %u, _tunnel_turnaround_pre_visibility_frame[dir]: %u", frame, rv->frame, dir, _tunnel_turnaround_pre_visibility_frame[dir]);
 					rv->tile = tile;
-					rv->cur_image_valid_dir = INVALID_DIR;
+					rv->InvalidateImageCache();
 					rv->state = RVSB_WORMHOLE;
 					if (Tunnel::GetByTile(tile)->is_chunnel) SetBit(rv->gv_flags, GVF_CHUNNEL_BIT);
 					rv->vehstatus |= VS_HIDDEN;
@@ -2710,7 +2710,7 @@ static VehicleEnterTileStatus VehicleEnter_TunnelBridge(Vehicle *v, TileIndex ti
 			if (dir == ReverseDiagDir(vdir) && frame == (int) (_tunnel_visibility_frame[dir] - 1) && z == 0) {
 				if (rv->tile != tile && GetOtherTunnelEnd(rv->tile) != tile) return VETSB_CONTINUE; // In chunnel
 				rv->tile = tile;
-				rv->cur_image_valid_dir = INVALID_DIR;
+				rv->InvalidateImageCache();
 				rv->state = DiagDirToDiagTrackdir(vdir);
 				rv->frame = TILE_SIZE - (frame + 1);
 				rv->vehstatus &= ~VS_HIDDEN;
@@ -2753,7 +2753,7 @@ static VehicleEnterTileStatus VehicleEnter_TunnelBridge(Vehicle *v, TileIndex ti
 						if (HasRoadTypeTram(tile) && HasBit(rv->compatible_roadtypes, GetRoadTypeTram(tile))) bits |= GetCustomBridgeHeadRoadBits(tile, RTT_TRAM);
 						if (!(bits & DiagDirToRoadBits(GetTunnelBridgeDirection(tile)))) return VETSB_CONTINUE;
 					}
-					rv->cur_image_valid_dir = INVALID_DIR;
+					rv->InvalidateImageCache();
 					rv->state = RVSB_WORMHOLE;
 					/* There are no slopes inside bridges / tunnels. */
 					ClrBit(rv->gv_flags, GVF_GOINGUP_BIT);
@@ -2790,7 +2790,7 @@ static VehicleEnterTileStatus VehicleEnter_TunnelBridge(Vehicle *v, TileIndex ti
 					v->tile = tile;
 					RoadVehicle *rv = RoadVehicle::From(v);
 					if (rv->state == RVSB_WORMHOLE) {
-						rv->cur_image_valid_dir = INVALID_DIR;
+						rv->InvalidateImageCache();
 						rv->state = DiagDirToDiagTrackdir(DirToDiagDir(v->direction));
 						rv->frame = 0;
 						return VETSB_ENTERED_WORMHOLE;

src/vehicle.cpp

@@ -340,6 +340,7 @@ uint Vehicle::Crash(bool flooded)
 		if (IsCargoInClass(v->cargo_type, CC_PASSENGERS)) pass += v->cargo.TotalCount();
 		v->vehstatus |= VS_CRASHED;
 		v->MarkAllViewportsDirty();
+		v->InvalidateImageCache();
 	}
 
 	this->ClearSeparation();
@@ -3757,6 +3758,8 @@ char *Vehicle::DumpVehicleFlags(char *b, const char *last, bool include_tile) co
 	dump('l', HasBit(this->vcache.cached_veh_flags, VCF_LAST_VISUAL_EFFECT));
 	dump('z', HasBit(this->vcache.cached_veh_flags, VCF_GV_ZERO_SLOPE_RESIST));
 	dump('d', HasBit(this->vcache.cached_veh_flags, VCF_IS_DRAWN));
+	dump('t', HasBit(this->vcache.cached_veh_flags, VCF_REDRAW_ON_TRIGGER));
+	dump('s', HasBit(this->vcache.cached_veh_flags, VCF_REDRAW_ON_SPEED_CHANGE));
 	if (this->IsGroundVehicle()) {
 		uint16 gv_flags = this->GetGroundVehicleFlags();
 		b += seprintf(b, last, ", gvf:");

src/vehicle_base.h

@@ -22,6 +22,7 @@
 #include "group_type.h"
 #include "timetable.h"
 #include "base_consist.h"
+#include "newgrf_cache_check.h"
 #include "network/network.h"
 #include <list>
 #include <map>
@@ -137,6 +138,8 @@ enum VehicleCacheFlags {
 	VCF_LAST_VISUAL_EFFECT      = 0, ///< Last vehicle in the consist with a visual effect.
 	VCF_GV_ZERO_SLOPE_RESIST    = 1, ///< GroundVehicle: Consist has zero slope resistance (valid only for the first engine), may be false negative.
 	VCF_IS_DRAWN                = 2, ///< Vehicle is currently drawn
+	VCF_REDRAW_ON_TRIGGER       = 3, ///< Clear cur_image_valid_dir on changes to waiting_triggers (valid only for the first engine)
+	VCF_REDRAW_ON_SPEED_CHANGE  = 4, ///< Clear cur_image_valid_dir on changes to cur_speed (ground vehicles) or aircraft movement state (aircraft) (valid only for the first engine)
 };
 
 /** Cached often queried values common to all vehicles. */
@@ -502,6 +505,28 @@ public:
 		}
 	}
 
+	/**
+	 * Invalidates cached image
+	 * @see InvalidateNewGRFCacheOfChain
+	 */
+	inline void InvalidateImageCache()
+	{
+		this->cur_image_valid_dir = INVALID_DIR;
+	}
+
+	/**
+	 * Invalidates cached image of all vehicles in the chain (after the current vehicle)
+	 * @see InvalidateImageCache
+	 */
+	inline void InvalidateImageCacheOfChain()
+	{
+		ClrBit(this->vcache.cached_veh_flags, VCF_REDRAW_ON_SPEED_CHANGE);
+		ClrBit(this->vcache.cached_veh_flags, VCF_REDRAW_ON_TRIGGER);
+		for (Vehicle *u = this; u != nullptr; u = u->Next()) {
+			u->InvalidateImageCache();
+		}
+	}
+
 	/**
 	 * Check if the vehicle is a ground vehicle.
 	 * @return True iff the vehicle is a train or a road vehicle.
@@ -1242,16 +1267,12 @@ struct SpecializedVehicle : public Vehicle {
 		/* Skip updating sprites on dedicated servers without screen */
 		if (_network_dedicated) return;
 
-		extern bool _sprite_group_resolve_check_veh_check;
-		extern VehicleType _sprite_group_resolve_check_veh_type;
-
 		/* Explicitly choose method to call to prevent vtable dereference -
 		 * it gives ~3% runtime improvements in games with many vehicles */
 		if (update_delta) ((T *)this)->T::UpdateDeltaXY();
 		const Direction current_direction = ((T *)this)->GetMapImageDirection();
 		if (this->cur_image_valid_dir != current_direction) {
 			_sprite_group_resolve_check_veh_check = true;
-			_sprite_group_resolve_check_veh_type = EXPECTED_TYPE;
 			VehicleSpriteSeq seq;
 			((T *)this)->T::GetImage(current_direction, EIT_ON_MAP, &seq);
 			this->cur_image_valid_dir = _sprite_group_resolve_check_veh_check ? current_direction : INVALID_DIR;