Biomes: Remove referenced biomes from Decorations on clear

src/gamedef.h

@@ -31,6 +31,7 @@ class ISoundManager;
 class IShaderSource;
 class MtEventManager;
 class IRollbackManager;
+class EmergeManager;
 namespace irr { namespace scene {
 	class IAnimatedMesh;
 	class ISceneManager;
@@ -70,6 +71,9 @@ public:
 	// environment thread.
 	virtual IRollbackManager* getRollbackManager(){return NULL;}
 
+	// Only usable on the server. Thread safe if not written while running threads.
+	virtual EmergeManager *getEmergeManager() { return NULL; }
+
 	// Used on the client
 	virtual bool checkLocalPrivilege(const std::string &priv)
 	{ return false; }
@@ -83,6 +87,7 @@ public:
 	IShaderSource    *shsrc()    { return getShaderSource(); }
 	MtEventManager   *event()    { return getEventManager(); }
 	IRollbackManager *rollback() { return getRollbackManager();}
+	EmergeManager    *emerge()   { return getEmergeManager(); }
 };
 
 #endif

src/mapgen.h

@@ -229,6 +229,8 @@ public:
 	virtual ObjDef *getRaw(u32 index) const;
 	virtual ObjDef *setRaw(u32 index, ObjDef *obj);
 
+	size_t getNumObjects() const { return m_objects.size(); }
+	ObjDefType getType() const { return m_objtype; }
 	INodeDefManager *getNodeDef() const { return m_ndef; }
 
 	u32 validateHandle(ObjDefHandle handle) const;

src/mg_biome.cpp

@@ -18,6 +18,8 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 */
 
 #include "mg_biome.h"
+#include "mg_decoration.h"
+#include "emerge.h"
 #include "gamedef.h"
 #include "nodedef.h"
 #include "map.h" //for MMVManip
@@ -33,6 +35,8 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 BiomeManager::BiomeManager(IGameDef *gamedef) :
 	ObjDefManager(gamedef, OBJDEF_BIOME)
 {
+	m_gamedef = gamedef;
+
 	// Create default biome to be used in case none exist
 	Biome *b = new Biome;
 
@@ -103,7 +107,16 @@ Biome *BiomeManager::getBiome(float heat, float humidity, s16 y)
 
 void BiomeManager::clear()
 {
+	EmergeManager *emerge = m_gamedef->getEmergeManager();
 
+	// Remove all dangling references in Decorations
+	DecorationManager *decomgr = emerge->decomgr;
+	for (size_t i = 0; i != decomgr->getNumObjects(); i++) {
+		Decoration *deco = (Decoration *)decomgr->getRaw(i);
+		deco->biomes.clear();
+	}
+
+	// Don't delete the first biome
 	for (size_t i = 1; i < m_objects.size(); i++) {
 		Biome *b = (Biome *)m_objects[i];
 		delete b;

src/mg_biome.h

@@ -78,6 +78,9 @@ public:
 	void calcBiomes(s16 sx, s16 sy, float *heat_map, float *humidity_map,
 		s16 *height_map, u8 *biomeid_map);
 	Biome *getBiome(float heat, float humidity, s16 y);
+
+private:
+	IGameDef *m_gamedef;
 };
 
 #endif

src/script/lua_api/l_mapgen.cpp

@@ -1039,7 +1039,6 @@ int ModApiMapgen::l_create_schematic(lua_State *L)
 	Schematic schem;
 
 	Map *map = &(getEnv(L)->getMap());
-	INodeDefManager *ndef = getServer(L)->getNodeDefManager();
 
 	v3s16 p1 = read_v3s16(L, 1);
 	v3s16 p2 = read_v3s16(L, 2);

src/server.h

@@ -297,9 +297,6 @@ public:
 	// Envlock and conlock should be locked when using scriptapi
 	GameScripting *getScriptIface(){ return m_script; }
 
-	//TODO: determine what (if anything) should be locked to access EmergeManager
-	EmergeManager *getEmergeManager(){ return m_emerge; }
-
 	// actions: time-reversed list
 	// Return value: success/failure
 	bool rollbackRevertActions(const std::list<RollbackAction> &actions,
@@ -317,7 +314,7 @@ public:
 	virtual MtEventManager* getEventManager();
 	virtual scene::ISceneManager* getSceneManager();
 	virtual IRollbackManager *getRollbackManager() { return m_rollback; }
-
+	virtual EmergeManager *getEmergeManager() { return m_emerge; }
 
 	IWritableItemDefManager* getWritableItemDefManager();
 	IWritableNodeDefManager* getWritableNodeDefManager();