1 files changed, 71 insertions, 0 deletions
diff --git a/src/newgrf_house.h b/src/newgrf_house.h
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+++ b/src/newgrf_house.h
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+/* $Id$ */
+
+/** @file newgrf_house.h */
+
+#ifndef NEWGRF_HOUSE_H
+#define NEWGRF_HOUSE_H
+
+#include "town.h"
+
+/**
+ * Maps a house id stored on the map to a GRF file.
+ * House IDs are stored on the map, so there needs to be a way to tie them to
+ * GRF files. An array of HouseIDMapping structs is saved with the savegame so
+ * that house GRFs can be loaded in a different order, or removed safely. The
+ * index in the array is the house ID stored on the map.
+ *
+ * The substitute ID is the ID of an original house that should be used instead
+ * if the GRF containing the new house is not available.
+ */
+struct HouseIDMapping {
+	uint32 grfid;          ///< The GRF ID of the file this house belongs to
+	uint8  house_id;       ///< The house ID within the GRF file
+	uint8  substitute_id;  ///< The (original) house ID to use if this GRF is not available
+};
+
+/**
+ * Makes class IDs unique to each GRF file.
+ * Houses can be assigned class IDs which are only comparable within the GRF
+ * file they were defined in. This mapping ensures that if two houses have the
+ * same class as defined by the GRF file, the classes are different within the
+ * game. An array of HouseClassMapping structs is created, and the array index
+ * of the struct that matches both the GRF ID and the class ID is the class ID
+ * used in the game.
+ *
+ * Although similar to the HouseIDMapping struct above, this serves a different
+ * purpose. Since the class ID is not saved anywhere, this mapping does not
+ * need to be persistent; it just needs to keep class ids unique.
+ */
+struct HouseClassMapping {
+	uint32 grfid;     ////< The GRF ID of the file this class belongs to
+	uint8  class_id;  ////< The class id within the grf file
+};
+
+extern HouseIDMapping _house_id_mapping[HOUSE_MAX]; ///< Declared in newgrf_house.cpp
+
+void AddHouseOverride(uint8 local_id, uint house_type);
+void ResetHouseOverrides();
+
+void SetHouseSpec(const HouseSpec *hs);
+
+void CheckHouseIDs();
+void ResetHouseIDMapping();
+
+HouseClassID AllocateHouseClassID(byte grf_class_id, uint32 grfid);
+
+void InitializeBuildingCounts();
+void IncreaseBuildingCount(Town *t, HouseID house_id);
+void DecreaseBuildingCount(Town *t, HouseID house_id);
+void AfterLoadCountBuildings();
+
+void DrawNewHouseTile(TileInfo *ti, HouseID house_id);
+void AnimateNewHouseTile(TileIndex tile);
+void ChangeHouseAnimationFrame(TileIndex tile, uint16 callback_result);
+
+uint16 GetHouseCallback(uint16 callback, uint32 param1, HouseID house_id, Town *town, TileIndex tile);
+
+bool CanDeleteHouse(TileIndex tile);
+
+bool NewHouseTileLoop(TileIndex tile);
+
+#endif /* NEWGRF_HOUSE_H */