(svn r3649) Turn several if-cascades into switch()es

road_cmd.c

@@ -34,13 +34,11 @@ static bool HasTileRoadAt(TileIndex tile, int i)
 	case MP_STREET:
 		b = _m[tile].m5;
 
-		if ((b & 0xF0) == 0) {
+		switch (b & 0xF0) {
-		} else if (IsLevelCrossing(tile)) {
+			case 0: break; // normal road
-			b = (b&8)?5:10;
+			case 1: b = (b & 8 ? 5 : 10); break; // level crossing
-		} else if ((b & 0xF0) == 0x20) {
+			case 2: return (~b & 3) == i; // depot
-			return (~b & 3) == i;
+			default: return false;
-		} else {
-			return false;
 		}
 		break;
 
@@ -177,16 +175,17 @@ int32 CmdRemoveRoad(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 		if (!b) return CMD_ERROR;
 	}
 
-	if (ti.type == MP_TUNNELBRIDGE) {
+	switch (ti.type) {
-		if (!EnsureNoVehicleZ(tile, TilePixelHeight(tile)))
+		case MP_TUNNELBRIDGE:
-			return CMD_ERROR;
+			if (!EnsureNoVehicleZ(tile, TilePixelHeight(tile))) return CMD_ERROR;
 
 			if ((ti.map5 & 0xE9) == 0xE8) {
 				if (pieces & 10) goto return_error;
 			} else if ((ti.map5 & 0xE9) == 0xE9) {
 				if (pieces & 5) goto return_error;
-		} else
+			} else {
 				goto return_error;
+			}
 
 			cost = _price.remove_road * 2;
 
@@ -197,13 +196,14 @@ int32 CmdRemoveRoad(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 				MarkTileDirtyByTile(tile);
 			}
 			return cost;
-	} else if (ti.type == MP_STREET) {
+
+		case MP_STREET:
 			// check if you're allowed to remove the street owned by a town
 			// removal allowance depends on difficulty setting
 			if (!CheckforTownRating(flags, t, ROAD_REMOVE)) return CMD_ERROR;
 
-		// XXX - change cascading ifs to switch when doing rewrite
+			switch (GB(ti.map5, 4, 4)) {
-		if ((ti.map5 & 0xF0) == 0) { // normal road
+				case 0: { // normal road
 					byte c = pieces, t2;
 
 					if (ti.tileh != 0  && (ti.map5 == 5 || ti.map5 == 10)) {
@@ -232,7 +232,9 @@ int32 CmdRemoveRoad(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 						}
 					}
 					return cost;
-		} else if ((ti.map5 & 0xE0) == 0) { // railroad crossing
+				}
+
+				case 1: { // level crossing
 					byte c;
 
 					if (!(ti.map5 & 8)) {
@@ -255,10 +257,13 @@ int32 CmdRemoveRoad(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 						);
 					}
 					return cost;
-		} else
+				}
-			goto return_error;
 
-	} else {
+				default: // depot
+					goto return_error;
+			}
+
+		default:
 return_error:;
 			return_cmd_error(INVALID_STRING_ID);
 	}
@@ -366,7 +371,8 @@ int32 CmdBuildRoad(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 	// allow building road under bridge
 	if (ti.type != MP_TUNNELBRIDGE && !EnsureNoVehicle(tile)) return CMD_ERROR;
 
-	if (ti.type == MP_STREET) {
+	switch (ti.type) {
+		case MP_STREET:
 			if (!(ti.map5 & 0xF0)) {
 				if ((pieces & (byte)ti.map5) == pieces)
 					return_cmd_error(STR_1007_ALREADY_BUILT);
@@ -376,7 +382,9 @@ int32 CmdBuildRoad(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 					return_cmd_error(STR_1007_ALREADY_BUILT);
 				goto do_clear;
 			}
-	} else if (ti.type == MP_RAILWAY) {
+			break;
+
+		case MP_RAILWAY: {
 			byte m5;
 
 			if (IsSteepTileh(ti.tileh)) { // very steep tile
@@ -408,7 +416,9 @@ int32 CmdBuildRoad(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 				);
 			}
 			return _price.build_road * 2;
-	} else if (ti.type == MP_TUNNELBRIDGE) {
+		}
+
+		case MP_TUNNELBRIDGE:
 			/* check for flat land */
 			if (IsSteepTileh(ti.tileh)) { // very steep tile
 				return_cmd_error(STR_1000_LAND_SLOPED_IN_WRONG_DIRECTION);
@@ -438,7 +448,8 @@ int32 CmdBuildRoad(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 				);
 			}
 			return cost;
-	} else {
+
+		default:
 do_clear:;
 			if (CmdFailed(DoCommandByTile(tile, 0, 0, flags & ~DC_EXEC, CMD_LANDSCAPE_CLEAR)))
 				return CMD_ERROR;
@@ -680,32 +691,40 @@ static int32 RemoveRoadDepot(TileIndex tile, uint32 flags)
 
 static int32 ClearTile_Road(TileIndex tile, byte flags)
 {
-	int32 ret;
 	byte m5 = _m[tile].m5;
 
-	if ( (m5 & 0xF0) == 0) {
+	switch (GB(_m[tile].m5, 4, 4)) {
+		case 0: { // normal road
 			byte b = m5 & 0xF;
 
-		if (! ((1 << b) & (M(1)|M(2)|M(4)|M(8))) ) {
+			if (!((1 << b) & (M(1)|M(2)|M(4)|M(8))) &&
-			if ((!(flags & DC_AI_BUILDING) || !IsTileOwner(tile, OWNER_TOWN)) && flags & DC_AUTO)
+					(!(flags & DC_AI_BUILDING) || !IsTileOwner(tile, OWNER_TOWN)) &&
+					flags & DC_AUTO) {
 				return_cmd_error(STR_1801_MUST_REMOVE_ROAD_FIRST);
 			}
 			return DoCommandByTile(tile, b, 0, flags, CMD_REMOVE_ROAD);
-	} else if ( (m5 & 0xE0) == 0) {
+		}
-		if (flags & DC_AUTO)
-			return_cmd_error(STR_1801_MUST_REMOVE_ROAD_FIRST);
 
-		ret = DoCommandByTile(tile, (m5&8)?5:10, 0, flags, CMD_REMOVE_ROAD);
+		case 1: { // level crossing
+			int32 ret;
+
+			if (flags & DC_AUTO) {
+				return_cmd_error(STR_1801_MUST_REMOVE_ROAD_FIRST);
+			}
+
+			ret = DoCommandByTile(tile, (m5 & 8 ? 5 : 10), 0, flags, CMD_REMOVE_ROAD);
 			if (CmdFailed(ret)) return CMD_ERROR;
 
 			if (flags & DC_EXEC) {
 				DoCommandByTile(tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
 			}
-
 			return ret;
-	} else {
+		}
-		if (flags & DC_AUTO)
+
+		default: // depot
+			if (flags & DC_AUTO) {
 				return_cmd_error(STR_2004_BUILDING_MUST_BE_DEMOLISHED);
+			}
 			return RemoveRoadDepot(tile, flags);
 	}
 }
@@ -825,9 +844,12 @@ static void DrawTile_Road(TileInfo *ti)
 	PalSpriteID image;
 	uint16 m2;
 
-	if ( (ti->map5 & 0xF0) == 0) { // if it is a road the upper 4 bits are 0
+	switch (GB(ti->map5, 4, 4)) {
+		case 0: // normal road
 			DrawRoadBits(ti, GB(ti->map5, 0, 4), GB(_m[ti->tile].m4, 4, 3), HASBIT(_m[ti->tile].m4, 7), false);
-	} else if ( (ti->map5 & 0xE0) == 0) { // railroad crossing
+			break;
+
+		case 1: { // level crossing
 			int f = GetRoadFoundation(ti->tileh, ti->map5 & 0xF);
 			if (f) DrawFoundation(ti, f);
 
@@ -835,8 +857,7 @@ static void DrawTile_Road(TileInfo *ti)
 
 			if (GB(ti->map5, 3, 1) == 0) image++; /* direction */
 
-		if ( (ti->map5 & 4) != 0)
+			if ((ti->map5 & 4) != 0) image += 2;
-			image += 2;
 
 			if ( _m[ti->tile].m4 & 0x80) {
 				image += 8;
@@ -847,17 +868,19 @@ static void DrawTile_Road(TileInfo *ti)
 			}
 
 			DrawGroundSprite(image);
-	} else {
+			break;
+		}
+
+		default: { // depot
 			uint32 ormod;
 			PlayerID player;
 			const DrawRoadSeqStruct* drss;
 
-		if (ti->tileh != 0) { DrawFoundation(ti, ti->tileh); }
+			if (ti->tileh != 0) DrawFoundation(ti, ti->tileh);
 
 			ormod = PALETTE_TO_GREY;	//was this a bug/problem?
 			player = GetTileOwner(ti->tile);
-		if (player < MAX_PLAYERS)
+			if (player < MAX_PLAYERS) ormod = PLAYER_SPRITE_COLOR(player);
-			ormod = PLAYER_SPRITE_COLOR(player);
 
 			drss = _road_display_datas[ti->map5 & 0xF];
 
@@ -866,13 +889,14 @@ static void DrawTile_Road(TileInfo *ti)
 			for (; drss->image != 0; drss++) {
 				uint32 image = drss->image;
 
-			if (image & PALETTE_MODIFIER_COLOR)
+				if (image & PALETTE_MODIFIER_COLOR) image |= ormod;
-				image |= ormod;
+				if (_display_opt & DO_TRANS_BUILDINGS) MAKE_TRANSPARENT(image);
-			if (_display_opt & DO_TRANS_BUILDINGS) // show transparent depots
-				MAKE_TRANSPARENT(image);
 
 				AddSortableSpriteToDraw(image, ti->x | drss->subcoord_x,
-				ti->y | drss->subcoord_y, drss->width, drss->height, 0x14, ti->z);
+					ti->y | drss->subcoord_y, drss->width, drss->height, 0x14, ti->z
+				);
+			}
+			break;
 		}
 	}
 }
@@ -908,7 +932,9 @@ static uint GetSlopeZ_Road(const TileInfo* ti)
 
 	// check if it's a foundation
 	if (ti->tileh != 0) {
-		if ((ti->map5 & 0xE0) == 0) { /* road or crossing */
+		switch (GB(ti->map5, 4, 4)) {
+			case 0: // normal road
+			case 1: { // level crossing
 				uint f = GetRoadFoundation(ti->tileh, ti->map5 & 0x3F);
 				if (f != 0) {
 					if (f < 15) {
@@ -918,9 +944,13 @@ static uint GetSlopeZ_Road(const TileInfo* ti)
 					// inclined foundation
 					th = _inclined_tileh[f - 15];
 				}
-		} else if ((ti->map5 & 0xF0) == 0x20) {
+				break;
-			// depot
+			}
+
+			case 2: // depot
 				return z + 8;
+
+			default: break;
 		}
 		return GetPartialZ(ti->x&0xF, ti->y&0xF, th) + z;
 	}
@@ -931,7 +961,9 @@ static uint GetSlopeTileh_Road(const TileInfo *ti)
 {
 	// check if it's a foundation
 	if (ti->tileh != 0) {
-		if ((ti->map5 & 0xE0) == 0) { /* road or crossing */
+		switch (GB(ti->map5, 4, 4)) {
+			case 0: // normal road
+			case 1: { // level crossing
 				uint f = GetRoadFoundation(ti->tileh, ti->map5 & 0x3F);
 				if (f != 0) {
 					if (f < 15) {
@@ -941,9 +973,13 @@ static uint GetSlopeTileh_Road(const TileInfo *ti)
 					// inclined foundation
 					return _inclined_tileh[f - 15];
 				}
-		} else if ((ti->map5 & 0xF0) == 0x20) {
+				break;
-			// depot
+			}
+
+			case 2: // depot
 				return 0;
+
+			default: break;
 		}
 	}
 	return ti->tileh;
@@ -1125,20 +1161,26 @@ static const byte _roadveh_enter_depot_unk0[4] = {
 
 static uint32 VehicleEnter_Road(Vehicle *v, TileIndex tile, int x, int y)
 {
-	if (IsLevelCrossing(tile)) {
+	switch (GB(_m[tile].m5, 4, 4)) {
+		case 1: // level crossing
 			if (v->type == VEH_Train && GB(_m[tile].m5, 2, 1) == 0) {
 				/* train crossing a road */
 				SndPlayVehicleFx(SND_0E_LEVEL_CROSSING, v);
 				SB(_m[tile].m5, 2, 1, 1);
 				MarkTileDirtyByTile(tile);
 			}
-	} else if (GB(_m[tile].m5, 4, 4) == 2) {
+			break;
+
+		case 2: // depot
 			if (v->type == VEH_Road && v->u.road.frame == 11) {
 				if (_roadveh_enter_depot_unk0[GB(_m[tile].m5, 0, 2)] == v->u.road.state) {
 					RoadVehEnterDepot(v);
 					return 4;
 				}
 			}
+			break;
+
+		default: break;
 	}
 	return 0;
 }
@@ -1164,15 +1206,21 @@ static void ChangeTileOwner_Road(TileIndex tile, PlayerID old_player, PlayerID n
 	if (new_player != OWNER_SPECTATOR) {
 		SetTileOwner(tile, new_player);
 	}	else {
-		if (GB(_m[tile].m5, 4, 4) == 0) {
+		switch (GB(_m[tile].m5, 4, 4)) {
+			case 0: // normal road
 				SetTileOwner(tile, OWNER_NONE);
-		} else if (IsLevelCrossing(tile)) {
+				break;
+
+			case 1: // level crossing
 				_m[tile].m5 = (_m[tile].m5&8) ? 0x5 : 0xA;
 				SetTileOwner(tile, _m[tile].m3);
 				_m[tile].m3 = 0;
 				_m[tile].m4 &= 0x80;
-		} else {
+				break;
+
+			default: // depot
 				DoCommandByTile(tile, 0, 0, DC_EXEC, CMD_LANDSCAPE_CLEAR);
+				break;
 		}
 	}
 }