Merge 643dcefc8f into 10eeba86a6

Move various base offsets to separate functions where they can be reused and documented.

No longer rely on coincidences to select the correct data between bridges and aqueducts.

src/driver.cpp

@@ -134,7 +134,7 @@ bool DriverFactoryBase::SelectDriverImpl(const std::string &name, Driver::Type t
 						Debug(driver, 1, "Probing {} driver '{}' skipped due to earlier crash", GetDriverTypeName(type), d->name);
 
 						_video_hw_accel = false;
-						ErrorMessageData msg(GetEncodedString(STR_VIDEO_DRIVER_ERROR), GetEncodedString(STR_VIDEO_DRIVER_ERROR_HARDWARE_ACCELERATION_CRASH), true);
+						ErrorMessageData msg(GetEncodedString(STR_VIDEO_DRIVER_ERROR), GetEncodedString(STR_VIDEO_DRIVER_ERROR_HARDWARE_ACCELERATION_CRASH), WL_CRITICAL);
 						ScheduleErrorMessage(std::move(msg));
 						continue;
 					}
@@ -158,7 +158,7 @@ bool DriverFactoryBase::SelectDriverImpl(const std::string &name, Driver::Type t
 
 				if (type == Driver::DT_VIDEO && _video_hw_accel && d->UsesHardwareAcceleration()) {
 					_video_hw_accel = false;
-					ErrorMessageData msg(GetEncodedString(STR_VIDEO_DRIVER_ERROR), GetEncodedString(STR_VIDEO_DRIVER_ERROR_NO_HARDWARE_ACCELERATION), true);
+					ErrorMessageData msg(GetEncodedString(STR_VIDEO_DRIVER_ERROR), GetEncodedString(STR_VIDEO_DRIVER_ERROR_NO_HARDWARE_ACCELERATION), WL_CRITICAL);
 					ScheduleErrorMessage(std::move(msg));
 				}
 			}

src/error.h

@@ -30,7 +30,7 @@ enum WarningLevel : uint8_t {
 /** The data of the error message. */
 class ErrorMessageData {
 protected:
-	bool is_critical;               ///< Whether the error message is critical.
+	WarningLevel level; ///< Level of the error message (e.g. whether it's a critical error).
 	EncodedString summary_msg; ///< General error message showed in first line. Must be valid.
 	EncodedString detailed_msg; ///< Detailed error message showed in second line. Can be #INVALID_STRING_ID.
 	EncodedString extra_msg; ///< Extra error message shown in third line. Can be #INVALID_STRING_ID.
@@ -38,7 +38,7 @@ protected:
 	CompanyID company; ///< Company belonging to the face being shown. #CompanyID::Invalid() if no face present.
 
 public:
-	ErrorMessageData(EncodedString &&summary_msg, EncodedString &&detailed_msg, bool is_critical = false, int x = 0, int y = 0, EncodedString &&extra_msg = {}, CompanyID company = CompanyID::Invalid());
+	ErrorMessageData(EncodedString &&summary_msg, EncodedString &&detailed_msg, WarningLevel level = WL_ERROR, int x = 0, int y = 0, EncodedString &&extra_msg = {}, CompanyID company = CompanyID::Invalid());
 
 	/** Check whether error window shall display a company manager face */
 	bool HasFace() const { return company != CompanyID::Invalid(); }

src/error_gui.cpp

@@ -35,10 +35,10 @@
 
 static constexpr NWidgetPart _nested_errmsg_widgets[] = {
 	NWidget(NWID_HORIZONTAL),
-		NWidget(WWT_CLOSEBOX, COLOUR_RED),
+		NWidget(WWT_CLOSEBOX, COLOUR_RED, WID_EM_CLOSEBOX),
 		NWidget(WWT_CAPTION, COLOUR_RED, WID_EM_CAPTION), SetStringTip(STR_ERROR_MESSAGE_CAPTION),
 	EndContainer(),
-	NWidget(WWT_PANEL, COLOUR_RED),
+	NWidget(WWT_PANEL, COLOUR_RED, WID_EM_PANEL),
 		NWidget(WWT_EMPTY, INVALID_COLOUR, WID_EM_MESSAGE), SetPadding(WidgetDimensions::unscaled.modalpopup), SetFill(1, 0), SetMinimalSize(236, 0),
 	EndContainer(),
 };
@@ -52,10 +52,10 @@ static WindowDesc _errmsg_desc(
 
 static constexpr NWidgetPart _nested_errmsg_face_widgets[] = {
 	NWidget(NWID_HORIZONTAL),
-		NWidget(WWT_CLOSEBOX, COLOUR_RED),
+		NWidget(WWT_CLOSEBOX, COLOUR_RED, WID_EM_CLOSEBOX),
 		NWidget(WWT_CAPTION, COLOUR_RED, WID_EM_CAPTION),
 	EndContainer(),
-	NWidget(WWT_PANEL, COLOUR_RED),
+	NWidget(WWT_PANEL, COLOUR_RED, WID_EM_PANEL),
 		NWidget(NWID_HORIZONTAL),
 			NWidget(WWT_EMPTY, INVALID_COLOUR, WID_EM_FACE), SetPadding(2, 0, 2, 2), SetFill(0, 1), SetMinimalSize(92, 119),
 			NWidget(WWT_EMPTY, INVALID_COLOUR, WID_EM_MESSAGE), SetPadding(WidgetDimensions::unscaled.modalpopup), SetFill(1, 1), SetMinimalSize(236, 0),
@@ -74,13 +74,13 @@ static WindowDesc _errmsg_face_desc(
  * Display an error message in a window.
  * @param summary_msg  General error message showed in first line. Must be valid.
  * @param detailed_msg Detailed error message showed in second line. Can be empty.
- * @param is_critical  Whether the error is critical. Critical messages never go away on their own.
+ * @param level        Warning/error level of the message. NOTE: critical messages never go away on their own.
  * @param x            World X position (TileVirtX) of the error location. Set both x and y to 0 to just center the message when there is no related error tile.
  * @param y            World Y position (TileVirtY) of the error location. Set both x and y to 0 to just center the message when there is no related error tile.
  * @param extra_msg    Extra error message showed in third line. Can be empty.
  */
-ErrorMessageData::ErrorMessageData(EncodedString &&summary_msg, EncodedString &&detailed_msg, bool is_critical, int x, int y, EncodedString &&extra_msg, CompanyID company) :
-	is_critical(is_critical),
+ErrorMessageData::ErrorMessageData(EncodedString &&summary_msg, EncodedString &&detailed_msg, WarningLevel level, int x, int y, EncodedString &&extra_msg, CompanyID company) :
+	level(level),
 	summary_msg(std::move(summary_msg)),
 	detailed_msg(std::move(detailed_msg)),
 	extra_msg(std::move(extra_msg)),
@@ -113,8 +113,15 @@ public:
 	{
 		this->InitNested();
 
+		Colours window_colour = COLOUR_RED;
+		if (level == WL_INFO) window_colour = COLOUR_GREEN;
+		if (level == WL_WARNING) window_colour = COLOUR_ORANGE;
+		this->GetWidget<NWidgetCore>(WID_EM_CAPTION)->colour = window_colour;
+		this->GetWidget<NWidgetCore>(WID_EM_CLOSEBOX)->colour = window_colour;
+		this->GetWidget<NWidgetCore>(WID_EM_PANEL)->colour = window_colour;
+
 		/* Only start the timeout if the message is not critical. */
-		if (!this->is_critical) {
+		if (this->level != WL_CRITICAL) {
 			this->display_timeout.Reset();
 		}
 	}
@@ -225,7 +232,7 @@ public:
 	void OnMouseLoop() override
 	{
 		/* Disallow closing the window too easily, if timeout is disabled */
-		if (_right_button_down && !this->is_critical) this->Close();
+		if (_right_button_down && this->level != WL_CRITICAL) this->Close();
 	}
 
 	void Close([[maybe_unused]] int data = 0) override
@@ -241,7 +248,7 @@ public:
 	 */
 	bool IsCritical()
 	{
-		return this->is_critical;
+		return this->level == WL_CRITICAL;
 	}
 };
 
@@ -281,7 +288,7 @@ void UnshowCriticalError()
 
 /**
  * Display an error message in a window.
- * Note: CommandCost errors are always severity level WL_INFO.
+ * Note: CommandCost errors are always severity level WL_ERROR.
  * @param summary_msg  General error message showed in first line. Must be valid.
  * @param x            World X position (TileVirtX) of the error location. Set both x and y to 0 to just center the message when there is no related error tile.
  * @param y            World Y position (TileVirtY) of the error location. Set both x and y to 0 to just center the message when there is no related error tile.
@@ -292,7 +299,7 @@ void ShowErrorMessage(EncodedString &&summary_msg, int x, int y, CommandCost &cc
 	EncodedString error = std::move(cc.GetEncodedMessage());
 	if (error.empty()) error = GetEncodedStringIfValid(cc.GetErrorMessage());
 
-	ShowErrorMessage(std::move(summary_msg), std::move(error), WL_INFO, x, y,
+	ShowErrorMessage(std::move(summary_msg), std::move(error), WL_ERROR, x, y,
 		GetEncodedStringIfValid(cc.GetExtraErrorMessage()), cc.GetErrorOwner());
 }
 
@@ -323,12 +330,10 @@ void ShowErrorMessage(EncodedString &&summary_msg, EncodedString &&detailed_msg,
 		IConsolePrint(wl == WL_WARNING ? CC_WARNING : CC_ERROR, message);
 	}
 
-	bool is_critical = wl == WL_CRITICAL;
-
 	if (_game_mode == GM_BOOTSTRAP) return;
-	if (_settings_client.gui.errmsg_duration == 0 && !is_critical) return;
+	if (_settings_client.gui.errmsg_duration == 0 && wl != WL_CRITICAL) return;
 
-	ErrorMessageData data(std::move(summary_msg), std::move(detailed_msg), is_critical, x, y, std::move(extra_msg), company);
+	ErrorMessageData data(std::move(summary_msg), std::move(detailed_msg), wl, x, y, std::move(extra_msg), company);
 
 	ErrmsgWindow *w = dynamic_cast<ErrmsgWindow *>(FindWindowById(WC_ERRMSG, 0));
 	if (w != nullptr) {

src/table/bridge_land.h

@@ -36,10 +36,15 @@
 # define MW(a) {a, PALETTE_TO_STRUCT_WHITE}
 # define MC(a) {a, PALETTE_TO_STRUCT_CONCRETE}
 
-static const PalSpriteID _aqueduct_sprites[] = {
-	{ SPR_AQUEDUCT_MIDDLE_X, PAL_NONE }, {                  0x0, PAL_NONE }, { SPR_AQUEDUCT_PILLAR_X, PAL_NONE }, {                  0x0, PAL_NONE },
-	{ SPR_AQUEDUCT_MIDDLE_Y, PAL_NONE }, {                  0x0, PAL_NONE }, { SPR_AQUEDUCT_PILLAR_Y, PAL_NONE }, {                  0x0, PAL_NONE },
-	{  SPR_AQUEDUCT_RAMP_SW, PAL_NONE }, { SPR_AQUEDUCT_RAMP_SE, PAL_NONE }, {  SPR_AQUEDUCT_RAMP_NE, PAL_NONE }, { SPR_AQUEDUCT_RAMP_NW, PAL_NONE },
+/* Sprite table for middle part of aqueduct. */
+static const PalSpriteID _aqueduct_sprite_table_middle[] = {
+	{SPR_AQUEDUCT_MIDDLE_X, PAL_NONE}, {0x0, PAL_NONE}, {SPR_AQUEDUCT_PILLAR_X, PAL_NONE}, {0x0, PAL_NONE}, // AXIS_X
+	{SPR_AQUEDUCT_MIDDLE_Y, PAL_NONE}, {0x0, PAL_NONE}, {SPR_AQUEDUCT_PILLAR_Y, PAL_NONE}, {0x0, PAL_NONE}, // AIXS_Y
+};
+
+/* Sprite table for head part of aqueduct. */
+static const PalSpriteID _aqueduct_sprite_table_heads[] = {
+	{SPR_AQUEDUCT_RAMP_SW, PAL_NONE}, {SPR_AQUEDUCT_RAMP_SE, PAL_NONE}, {SPR_AQUEDUCT_RAMP_NE, PAL_NONE}, {SPR_AQUEDUCT_RAMP_NW, PAL_NONE},
 };
 
 static const PalSpriteID _bridge_sprite_table_4_0[] = {

src/tunnelbridge_cmd.cpp

@@ -138,15 +138,58 @@ bool HasBridgeFlatRamp(Slope tileh, Axis axis)
 	return (tileh != SLOPE_FLAT);
 }
 
-static inline std::span<const PalSpriteID> GetBridgeSpriteTable(int index, BridgePieces table)
+/**
+ * Get the sprite table for a rail/road bridge piece.
+ * @param bridge_type Bridge type.
+ * @param piece Bridge piece.
+ * @return Sprite table for the bridge piece.
+ */
+static std::span<const PalSpriteID> GetBridgeSpriteTable(BridgeType bridge_type, BridgePieces piece)
 {
-	const BridgeSpec *bridge = GetBridgeSpec(index);
-	assert(table < NUM_BRIDGE_PIECES);
-	if (table < bridge->sprite_table.size() && !bridge->sprite_table[table].empty()) return bridge->sprite_table[table];
+	assert(piece < NUM_BRIDGE_PIECES);
 
-	return _bridge_sprite_table[index][table];
+	const BridgeSpec *bridge = GetBridgeSpec(bridge_type);
+	if (piece < bridge->sprite_table.size() && !bridge->sprite_table[piece].empty()) return bridge->sprite_table[piece];
+
+	return _bridge_sprite_table[bridge_type][piece];
 }
 
+/**
+ * Get the sprite table transport type base offset for a rail/road bridge.
+ * @param transport_type Transport type of bridge.
+ * @param ramp Tile of bridge ramp.
+ * @return Offset for transport type.
+ */
+static uint8_t GetBridgeSpriteTableBaseOffset(TransportType transport_type, TileIndex ramp)
+{
+	switch (transport_type) {
+		case TRANSPORT_RAIL: return GetRailTypeInfo(GetRailType(ramp))->bridge_offset;
+		case TRANSPORT_ROAD: return 8;
+		default: NOT_REACHED();
+	}
+}
+
+/**
+ * Get bridge sprite table base offset for the ramp part of bridge.
+ * @param diagdir Direction of ramp.
+ * @return Offset for direction.
+ */
+static uint8_t GetBridgeRampDirectionBaseOffset(DiagDirection diagdir)
+{
+	/* Bridge ramps are ordered SW, SE, NE, NW instead of NE, SE, SW, NW. */
+	static constexpr uint8_t ramp_offsets[DIAGDIR_END] = {2, 1, 0, 3};
+	return ramp_offsets[diagdir];
+}
+
+/**
+ * Get bridge sprite table base offset for the middle part of bridge.
+ * @param axis Axis of bridge.
+ * @return Offset for axis.
+ */
+static uint8_t GetBridgeMiddleAxisBaseOffset(Axis axis)
+{
+	return axis == AXIS_X ? 0 : 4;
+}
 
 /**
  * Determines the foundation for the bridge head, and tests if the resulting slope is valid.
@@ -1017,10 +1060,10 @@ static CommandCost ClearTile_TunnelBridge(TileIndex tile, DoCommandFlags flags)
  * @param h         Bounding box size in Y direction
  * @param subsprite Optional subsprite for drawing halfpillars
  */
-static inline void DrawPillar(const PalSpriteID *psid, int x, int y, int z, uint8_t w, uint8_t h, const SubSprite *subsprite)
+static inline void DrawPillar(const PalSpriteID &psid, int x, int y, int z, uint8_t w, uint8_t h, const SubSprite *subsprite)
 {
 	static const int PILLAR_Z_OFFSET = TILE_HEIGHT - BRIDGE_Z_START; ///< Start offset of pillar wrt. bridge (downwards)
-	AddSortableSpriteToDraw(psid->sprite, psid->pal, x, y, z, {{0, 0, -PILLAR_Z_OFFSET}, {w, h, BB_HEIGHT_UNDER_BRIDGE}, {0, 0, PILLAR_Z_OFFSET}}, IsTransparencySet(TO_BRIDGES), subsprite);
+	AddSortableSpriteToDraw(psid.sprite, psid.pal, x, y, z, {{0, 0, -PILLAR_Z_OFFSET}, {w, h, BB_HEIGHT_UNDER_BRIDGE}, {0, 0, PILLAR_Z_OFFSET}}, IsTransparencySet(TO_BRIDGES), subsprite);
 }
 
 /**
@@ -1034,7 +1077,7 @@ static inline void DrawPillar(const PalSpriteID *psid, int x, int y, int z, uint
  * @param h        Bounding box size in Y direction
  * @return Reached Z at the bottom
  */
-static int DrawPillarColumn(int z_bottom, int z_top, const PalSpriteID *psid, int x, int y, int w, int h)
+static int DrawPillarColumn(int z_bottom, int z_top, const PalSpriteID &psid, int x, int y, int w, int h)
 {
 	int cur_z;
 	for (cur_z = z_top; cur_z >= z_bottom; cur_z -= TILE_HEIGHT) {
@@ -1054,7 +1097,7 @@ static int DrawPillarColumn(int z_bottom, int z_top, const PalSpriteID *psid, in
  * @param y Sprite Y position of front pillar.
  * @param z_bridge Absolute height of bridge bottom.
  */
-static void DrawBridgePillars(const PalSpriteID *psid, const TileInfo *ti, Axis axis, bool drawfarpillar, int x, int y, int z_bridge)
+static void DrawBridgePillars(const PalSpriteID &psid, const TileInfo *ti, Axis axis, bool drawfarpillar, int x, int y, int z_bridge)
 {
 	static const int bounding_box_size[2]  = {16, 2}; ///< bounding box size of pillars along bridge direction
 	static const int back_pillar_offset[2] = { 0, 9}; ///< sprite position offset of back facing pillar
@@ -1065,7 +1108,7 @@ static void DrawBridgePillars(const PalSpriteID *psid, const TileInfo *ti, Axis
 		{ { -INF, -INF,  15, INF }, {   16, -INF, INF, INF } }, // Y axis, north and south
 	};
 
-	if (psid->sprite == 0) return;
+	if (psid.sprite == 0) return;
 
 	/* Determine ground height under pillars */
 	DiagDirection south_dir = AxisToDiagDir(axis);
@@ -1404,34 +1447,20 @@ static void DrawTile_TunnelBridge(TileInfo *ti)
 
 		DrawBridgeMiddle(ti);
 	} else { // IsBridge(ti->tile)
-		const PalSpriteID *psid;
-		int base_offset;
-		bool ice = HasTunnelBridgeSnowOrDesert(ti->tile);
-
-		if (transport_type == TRANSPORT_RAIL) {
-			base_offset = GetRailTypeInfo(GetRailType(ti->tile))->bridge_offset;
-			assert(base_offset != 8); // This one is used for roads
-		} else {
-			base_offset = 8;
-		}
-
-		/* as the lower 3 bits are used for other stuff, make sure they are clear */
-		assert( (base_offset & 0x07) == 0x00);
-
 		DrawFoundation(ti, GetBridgeFoundation(ti->tileh, DiagDirToAxis(tunnelbridge_direction)));
 
-		/* HACK Wizardry to convert the bridge ramp direction into a sprite offset */
-		base_offset += (6 - tunnelbridge_direction) % 4;
-
-		/* Table number BRIDGE_PIECE_HEAD always refers to the bridge heads for any bridge type */
+		uint base_offset = GetBridgeRampDirectionBaseOffset(tunnelbridge_direction);
+		std::span<const PalSpriteID> psid;
 		if (transport_type != TRANSPORT_WATER) {
 			if (ti->tileh == SLOPE_FLAT) base_offset += 4; // sloped bridge head
-			psid = &GetBridgeSpriteTable(GetBridgeType(ti->tile), BRIDGE_PIECE_HEAD)[base_offset];
+			base_offset += GetBridgeSpriteTableBaseOffset(transport_type, ti->tile);
+			psid = GetBridgeSpriteTable(GetBridgeType(ti->tile), BRIDGE_PIECE_HEAD);
 		} else {
-			psid = _aqueduct_sprites + base_offset;
+			psid = _aqueduct_sprite_table_heads;
 		}
+		psid = psid.subspan(base_offset, 1);
 
-		if (!ice) {
+		if (!HasTunnelBridgeSnowOrDesert(ti->tile)) {
 			TileIndex next = ti->tile + TileOffsByDiagDir(tunnelbridge_direction);
 			if (ti->tileh != SLOPE_FLAT && ti->z == 0 && HasTileWaterClass(next) && GetWaterClass(next) == WATER_CLASS_SEA) {
 				DrawShoreTile(ti->tileh);
@@ -1451,7 +1480,7 @@ static void DrawTile_TunnelBridge(TileInfo *ti)
 		 * it doesn't disappear behind it
 		 */
 		/* Bridge heads are drawn solid no matter how invisibility/transparency is set */
-		AddSortableSpriteToDraw(psid->sprite, psid->pal, *ti, {{}, {TILE_SIZE, TILE_SIZE, static_cast<uint8_t>(ti->tileh == SLOPE_FLAT ? 0 : TILE_HEIGHT)}, {}});
+		AddSortableSpriteToDraw(psid[0].sprite, psid[0].pal, *ti, {{}, {TILE_SIZE, TILE_SIZE, static_cast<uint8_t>(ti->tileh == SLOPE_FLAT ? 0 : TILE_HEIGHT)}, {}});
 
 		if (transport_type == TRANSPORT_ROAD) {
 			uint offset = tunnelbridge_direction;
@@ -1572,33 +1601,21 @@ void DrawBridgeMiddle(const TileInfo *ti)
 	TileIndex rampnorth = GetNorthernBridgeEnd(ti->tile);
 	TileIndex rampsouth = GetSouthernBridgeEnd(ti->tile);
 	TransportType transport_type = GetTunnelBridgeTransportType(rampsouth);
-
 	Axis axis = GetBridgeAxis(ti->tile);
-	BridgePieces piece = CalcBridgePiece(
-		GetTunnelBridgeLength(ti->tile, rampnorth) + 1,
-		GetTunnelBridgeLength(ti->tile, rampsouth) + 1
-	);
 
-	const PalSpriteID *psid;
+	uint base_offset = GetBridgeMiddleAxisBaseOffset(axis);
+	std::span<const PalSpriteID> psid;
 	bool drawfarpillar;
 	if (transport_type != TRANSPORT_WATER) {
-		BridgeType type =  GetBridgeType(rampsouth);
-		drawfarpillar = !HasBit(GetBridgeSpec(type)->flags, 0);
-
-		uint base_offset;
-		if (transport_type == TRANSPORT_RAIL) {
-			base_offset = GetRailTypeInfo(GetRailType(rampsouth))->bridge_offset;
-		} else {
-			base_offset = 8;
-		}
-
-		psid = &GetBridgeSpriteTable(type, piece)[base_offset];
+		BridgeType bridge_type = GetBridgeType(rampsouth);
+		drawfarpillar = !HasBit(GetBridgeSpec(bridge_type)->flags, 0);
+		base_offset += GetBridgeSpriteTableBaseOffset(transport_type, rampsouth);
+		psid = GetBridgeSpriteTable(bridge_type, CalcBridgePiece(GetTunnelBridgeLength(ti->tile, rampnorth) + 1, GetTunnelBridgeLength(ti->tile, rampsouth) + 1));
 	} else {
 		drawfarpillar = true;
-		psid = _aqueduct_sprites;
+		psid = _aqueduct_sprite_table_middle;
 	}
-
-	if (axis != AXIS_X) psid += 4;
+	psid = psid.subspan(base_offset, 3);
 
 	int x = ti->x;
 	int y = ti->y;
@@ -1614,14 +1631,12 @@ void DrawBridgeMiddle(const TileInfo *ti)
 	/* Draw floor and far part of bridge*/
 	if (!IsInvisibilitySet(TO_BRIDGES)) {
 		if (axis == AXIS_X) {
-			AddSortableSpriteToDraw(psid->sprite, psid->pal, x, y, z, {{0, 0, BRIDGE_Z_START}, {TILE_SIZE, 1, 40}, {0, 0, -BRIDGE_Z_START}}, IsTransparencySet(TO_BRIDGES));
+			AddSortableSpriteToDraw(psid[0].sprite, psid[0].pal, x, y, z, {{0, 0, BRIDGE_Z_START}, {TILE_SIZE, 1, 40}, {0, 0, -BRIDGE_Z_START}}, IsTransparencySet(TO_BRIDGES));
 		} else {
-			AddSortableSpriteToDraw(psid->sprite, psid->pal, x, y, z, {{0, 0, BRIDGE_Z_START}, {1, TILE_SIZE, 40}, {0, 0, -BRIDGE_Z_START}}, IsTransparencySet(TO_BRIDGES));
+			AddSortableSpriteToDraw(psid[0].sprite, psid[0].pal, x, y, z, {{0, 0, BRIDGE_Z_START}, {1, TILE_SIZE, 40}, {0, 0, -BRIDGE_Z_START}}, IsTransparencySet(TO_BRIDGES));
 		}
 	}
 
-	psid++;
-
 	if (transport_type == TRANSPORT_ROAD) {
 		/* DrawBridgeRoadBits() calls EndSpriteCombine() and StartSpriteCombine() */
 		DrawBridgeRoadBits(rampsouth, x, y, bridge_z, axis ^ 1, false);
@@ -1654,10 +1669,10 @@ void DrawBridgeMiddle(const TileInfo *ti)
 	if (!IsInvisibilitySet(TO_BRIDGES)) {
 		if (axis == AXIS_X) {
 			y += 12;
-			if (psid->sprite & SPRITE_MASK) AddSortableSpriteToDraw(psid->sprite, psid->pal, x, y, z, {{0, 3, BRIDGE_Z_START}, {TILE_SIZE, 1, 40}, {0, -3, -BRIDGE_Z_START}}, IsTransparencySet(TO_BRIDGES));
+			if (psid[1].sprite & SPRITE_MASK) AddSortableSpriteToDraw(psid[1].sprite, psid[1].pal, x, y, z, {{0, 3, BRIDGE_Z_START}, {TILE_SIZE, 1, 40}, {0, -3, -BRIDGE_Z_START}}, IsTransparencySet(TO_BRIDGES));
 		} else {
 			x += 12;
-			if (psid->sprite & SPRITE_MASK) AddSortableSpriteToDraw(psid->sprite, psid->pal, x, y, z, {{3, 0, BRIDGE_Z_START}, {1, TILE_SIZE, 40}, {-3, 0, -BRIDGE_Z_START}}, IsTransparencySet(TO_BRIDGES));
+			if (psid[1].sprite & SPRITE_MASK) AddSortableSpriteToDraw(psid[1].sprite, psid[1].pal, x, y, z, {{3, 0, BRIDGE_Z_START}, {1, TILE_SIZE, 40}, {-3, 0, -BRIDGE_Z_START}}, IsTransparencySet(TO_BRIDGES));
 		}
 	}
 
@@ -1667,8 +1682,7 @@ void DrawBridgeMiddle(const TileInfo *ti)
 	/* Do not draw anything more if bridges are invisible */
 	if (IsInvisibilitySet(TO_BRIDGES)) return;
 
-	psid++;
-	DrawBridgePillars(psid, ti, axis, drawfarpillar, x, y, z);
+	DrawBridgePillars(psid[2], ti, axis, drawfarpillar, x, y, z);
 }
 
 

src/widgets/error_widget.h

@@ -12,9 +12,11 @@
 
 /** Widgets of the #ErrmsgWindow class. */
 enum ErrorMessageWidgets : WidgetID {
-	WID_EM_CAPTION, ///< Caption of the window.
-	WID_EM_FACE,    ///< Error title.
-	WID_EM_MESSAGE, ///< Error message.
+	WID_EM_CAPTION,  ///< Caption of the window.
+	WID_EM_FACE,     ///< Error title.
+	WID_EM_MESSAGE,  ///< Error message.
+	WID_EM_CLOSEBOX, ///< Close box button.
+	WID_EM_PANEL,    ///< Coloured background panel.
 };
 
 #endif /* WIDGETS_ERROR_WIDGET_H */