Node definition manager refactor (#7016)

* Rename IWritableNodeDefManager to NodeDefManager
* Make INodeDefManager functions const
* Use "const *NodeDefManager" instead of "*INodeDefManager"
* Remove unused INodeDefManager class
* Merge NodeDefManager and CNodeDefManager
* Document NodeDefManager

1 files changed, 277 insertions, 76 deletions

diff --git a/src/nodedef.h b/src/nodedef.h
index d46712310..f99f7f321 100644
--- a/src/nodedef.h
+++ b/src/nodedef.h
@@ -24,6 +24,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include <iostream>
 #include <map>
 #include "mapnode.h"
+#include "nameidmapping.h"
 #ifndef SERVER
 #include "client/tile.h"
 #include <IMeshManipulator.h>
@@ -34,7 +35,6 @@ class Client;
 #include "constants.h" // BS
 #include "tileanimation.h"
 
-class INodeDefManager;
 class IItemDefManager;
 class ITextureSource;
 class IShaderSource;
@@ -438,92 +438,293 @@ struct ContentFeatures
 #endif
 };
 
-class INodeDefManager {
+/*!
+ * @brief This class is for getting the actual properties of nodes from their
+ * content ID.
+ *
+ * @details The nodes on the map are represented by three numbers (see MapNode).
+ * The first number (param0) is the type of a node. All node types have own
+ * properties (see ContentFeatures). This class is for storing and getting the
+ * properties of nodes.
+ * The manager is first filled with registered nodes, then as the game begins,
+ * functions only get `const` pointers to it, to prevent modification of
+ * registered nodes.
+ */
+class NodeDefManager {
 public:
-	INodeDefManager() = default;
-	virtual ~INodeDefManager() = default;
-
-	// Get node definition
-	virtual const ContentFeatures &get(content_t c) const=0;
-	virtual const ContentFeatures &get(const MapNode &n) const=0;
-	virtual bool getId(const std::string &name, content_t &result) const=0;
-	virtual content_t getId(const std::string &name) const=0;
-	// Allows "group:name" in addition to regular node names
-	// returns false if node name not found, true otherwise
-	virtual bool getIds(const std::string &name, std::vector<content_t> &result)
-			const=0;
-	virtual const ContentFeatures &get(const std::string &name) const=0;
-
-	virtual void serialize(std::ostream &os, u16 protocol_version) const=0;
-
-	virtual void pendNodeResolve(NodeResolver *nr)=0;
-	virtual bool cancelNodeResolveCallback(NodeResolver *nr)=0;
-	virtual bool nodeboxConnects(const MapNode from, const MapNode to, u8 connect_face)=0;
-	/*!
-	 * Returns the smallest box in node coordinates that
-	 * contains all nodes' selection boxes.
+	/*!
+	 * Creates a NodeDefManager, and registers three ContentFeatures:
+	 * \ref CONTENT_AIR, \ref CONTENT_UNKNOWN and \ref CONTENT_IGNORE.
 	 */
-	virtual core::aabbox3d<s16> getSelectionBoxIntUnion() const=0;
-};
+	NodeDefManager();
+	~NodeDefManager();
 
-class IWritableNodeDefManager : public INodeDefManager {
-public:
-	IWritableNodeDefManager() = default;
-	virtual ~IWritableNodeDefManager() = default;
-
-	// Get node definition
-	virtual const ContentFeatures &get(content_t c) const=0;
-	virtual const ContentFeatures &get(const MapNode &n) const=0;
-	virtual bool getId(const std::string &name, content_t &result) const=0;
-	// If not found, returns CONTENT_IGNORE
-	virtual content_t getId(const std::string &name) const=0;
-	// Allows "group:name" in addition to regular node names
-	virtual bool getIds(const std::string &name, std::vector<content_t> &result)
-		const=0;
-	// If not found, returns the features of CONTENT_UNKNOWN
-	virtual const ContentFeatures &get(const std::string &name) const=0;
-
-	// Register node definition by name (allocate an id)
-	// If returns CONTENT_IGNORE, could not allocate id
-	virtual content_t set(const std::string &name,
-			const ContentFeatures &def)=0;
-	// If returns CONTENT_IGNORE, could not allocate id
-	virtual content_t allocateDummy(const std::string &name)=0;
-	// Remove a node
-	virtual void removeNode(const std::string &name)=0;
+	/*!
+	 * Returns the properties for the given content type.
+	 * @param c content type of a node
+	 * @return properties of the given content type, or \ref CONTENT_UNKNOWN
+	 * if the given content type is not registered.
+	 */
+	inline const ContentFeatures& get(content_t c) const {
+		return
+			c < m_content_features.size() ?
+				m_content_features[c] : m_content_features[CONTENT_UNKNOWN];
+	}
 
-	/*
-		Update item alias mapping.
-		Call after updating item definitions.
-	*/
-	virtual void updateAliases(IItemDefManager *idef)=0;
+	/*!
+	 * Returns the properties of the given node.
+	 * @param n a map node
+	 * @return properties of the given node or @ref CONTENT_UNKNOWN if the
+	 * given content type is not registered.
+	 */
+	inline const ContentFeatures& get(const MapNode &n) const {
+		return get(n.getContent());
+	}
 
-	/*
-		Override textures from servers with ones specified in texturepack/override.txt
-	*/
-	virtual void applyTextureOverrides(const std::string &override_filepath)=0;
+	/*!
+	 * Returns the node properties for a node name.
+	 * @param name name of a node
+	 * @return properties of the given node or @ref CONTENT_UNKNOWN if
+	 * not found
+	 */
+	const ContentFeatures& get(const std::string &name) const;
 
-	/*
-		Update tile textures to latest return values of TextueSource.
-	*/
-	virtual void updateTextures(IGameDef *gamedef,
+	/*!
+	 * Returns the content ID for the given name.
+	 * @param name a node name
+	 * @param[out] result will contain the content ID if found, otherwise
+	 * remains unchanged
+	 * @return true if the ID was found, false otherwise
+	 */
+	bool getId(const std::string &name, content_t &result) const;
+
+	/*!
+	 * Returns the content ID for the given name.
+	 * @param name a node name
+	 * @return ID of the node or @ref CONTENT_IGNORE if not found
+	 */
+	content_t getId(const std::string &name) const;
+
+	/*!
+	 * Returns the content IDs of the given node name or node group name.
+	 * Group names start with "group:".
+	 * @param name a node name or node group name
+	 * @param[out] result will be appended with matching IDs
+	 * @return true if `name` is a valid node name or a (not necessarily
+	 * valid) group name
+	 */
+	bool getIds(const std::string &name, std::vector<content_t> &result) const;
+
+	/*!
+	 * Returns the smallest box in integer node coordinates that
+	 * contains all nodes' selection boxes. The returned box might be larger
+	 * than the minimal size if the largest node is removed from the manager.
+	 */
+	inline core::aabbox3d<s16> getSelectionBoxIntUnion() const {
+		return m_selection_box_int_union;
+	}
+
+	/*!
+	 * Checks whether a node connects to an adjacent node.
+	 * @param from the node to be checked
+	 * @param to the adjacent node
+	 * @param connect_face a bit field indicating which face of the node is
+	 * adjacent to the other node.
+	 * Bits: +y (least significant), -y, -z, -x, +z, +x (most significant).
+	 * @return true if the node connects, false otherwise
+	 */
+	bool nodeboxConnects(MapNode from, MapNode to,
+			u8 connect_face) const;
+
+	/*!
+	 * Registers a NodeResolver to wait for the registration of
+	 * ContentFeatures. Once the node registration finishes, all
+	 * listeners are notified.
+	 */
+	void pendNodeResolve(NodeResolver *nr) const;
+
+	/*!
+	 * Stops listening to the NodeDefManager.
+	 * @return true if the listener was registered before, false otherwise
+	 */
+	bool cancelNodeResolveCallback(NodeResolver *nr) const;
+
+	/*!
+	 * Registers a new node type with the given name and allocates a new
+	 * content ID.
+	 * Should not be called with an already existing name.
+	 * @param name name of the node, must match with `def.name`.
+	 * @param def definition of the registered node type.
+	 * @return ID of the registered node or @ref CONTENT_IGNORE if
+	 * the function could not allocate an ID.
+	 */
+	content_t set(const std::string &name, const ContentFeatures &def);
+
+	/*!
+	 * Allocates a blank node ID for the given name.
+	 * @param name name of a node
+	 * @return allocated ID or @ref CONTENT_IGNORE if could not allocate
+	 * an ID.
+	 */
+	content_t allocateDummy(const std::string &name);
+
+	/*!
+	 * Removes the given node name from the manager.
+	 * The node ID will remain in the manager, but won't be linked to any name.
+	 * @param name name to be removed
+	 */
+	void removeNode(const std::string &name);
+
+	/*!
+	 * Regenerates the alias list (a map from names to node IDs).
+	 * @param idef the item definition manager containing alias information
+	 */
+	void updateAliases(IItemDefManager *idef);
+
+	/*!
+	 * Reads the used texture pack's override.txt, and replaces the textures
+	 * of registered nodes with the ones specified there.
+	 *
+	 * Format of the input file: in each line
+	 * `node_name top|bottom|right|left|front|back|all|*|sides texture_name.png`
+	 *
+	 * @param override_filepath path to 'texturepack/override.txt'
+	 */
+	void applyTextureOverrides(const std::string &override_filepath);
+
+	/*!
+	 * Only the client uses this. Loads textures and shaders required for
+	 * rendering the nodes.
+	 * @param gamedef must be a Client.
+	 * @param progress_cbk called each time a node is loaded. Arguments:
+	 * `progress_cbk_args`, number of loaded ContentFeatures, number of
+	 * total ContentFeatures.
+	 * @param progress_cbk_args passed to the callback function
+	 */
+	void updateTextures(IGameDef *gamedef,
 		void (*progress_cbk)(void *progress_args, u32 progress, u32 max_progress),
-		void *progress_cbk_args)=0;
+		void *progress_cbk_args);
+
+	/*!
+	 * Writes the content of this manager to the given output stream.
+	 * @param protocol_version serialization version of ContentFeatures
+	 */
+	void serialize(std::ostream &os, u16 protocol_version) const;
+
+	/*!
+	 * Restores the manager from a serialized stream.
+	 * This clears the previous state.
+	 * @param is input stream containing a serialized NodeDefManager
+	 */
+	void deSerialize(std::istream &is);
+
+	/*!
+	 * Used to indicate that node registration has finished.
+	 * @param completed tells whether registration is complete
+	 */
+	inline void setNodeRegistrationStatus(bool completed) {
+		m_node_registration_complete = completed;
+	}
+
+	/*!
+	 * Notifies the registered NodeResolver instances that node registration
+	 * has finished, then unregisters all listeners.
+	 * Must be called after node registration has finished!
+	 */
+	void runNodeResolveCallbacks();
+
+	/*!
+	 * Sets the registration completion flag to false and unregisters all
+	 * NodeResolver instances listening to the manager.
+	 */
+	void resetNodeResolveState();
 
-	virtual void serialize(std::ostream &os, u16 protocol_version) const=0;
-	virtual void deSerialize(std::istream &is)=0;
+	/*!
+	 * Resolves the IDs to which connecting nodes connect from names.
+	 * Must be called after node registration has finished!
+	 */
+	void mapNodeboxConnections();
 
-	virtual void setNodeRegistrationStatus(bool completed)=0;
+private:
+	/*!
+	 * Resets the manager to its initial state.
+	 * See the documentation of the constructor.
+	 */
+	void clear();
+
+	/*!
+	 * Allocates a new content ID, and returns it.
+	 * @return the allocated ID or \ref CONTENT_IGNORE if could not allocate
+	 */
+	content_t allocateId();
 
-	virtual void pendNodeResolve(NodeResolver *nr)=0;
-	virtual bool cancelNodeResolveCallback(NodeResolver *nr)=0;
-	virtual void runNodeResolveCallbacks()=0;
-	virtual void resetNodeResolveState()=0;
-	virtual void mapNodeboxConnections()=0;
-	virtual core::aabbox3d<s16> getSelectionBoxIntUnion() const=0;
+	/*!
+	 * Binds the given content ID and node name.
+	 * Registers them in \ref m_name_id_mapping and
+	 * \ref m_name_id_mapping_with_aliases.
+	 * @param i a content ID
+	 * @param name a node name
+	 */
+	void addNameIdMapping(content_t i, std::string name);
+
+	/*!
+	 * Recalculates m_selection_box_int_union based on
+	 * m_selection_box_union.
+	 */
+	void fixSelectionBoxIntUnion();
+
+	//! Features indexed by ID.
+	std::vector<ContentFeatures> m_content_features;
+
+	//! A mapping for fast conversion between names and IDs
+	NameIdMapping m_name_id_mapping;
+
+	/*!
+	 * Like @ref m_name_id_mapping, but maps only from names to IDs, and
+	 * includes aliases too. Updated by \ref updateAliases().
+	 * Note: Not serialized.
+	 */
+	std::unordered_map<std::string, content_t> m_name_id_mapping_with_aliases;
+
+	/*!
+	 * A mapping from group names to a vector of content types that belong
+	 * to it. Necessary for a direct lookup in \ref getIds().
+	 * Note: Not serialized.
+	 */
+	std::unordered_map<std::string, std::vector<content_t>> m_group_to_items;
+
+	/*!
+	 * The next ID that might be free to allocate.
+	 * It can be allocated already, because \ref CONTENT_AIR,
+	 * \ref CONTENT_UNKNOWN and \ref CONTENT_IGNORE are registered when the
+	 * manager is initialized, and new IDs are allocated from 0.
+	 */
+	content_t m_next_id;
+
+	//! True if all nodes have been registered.
+	bool m_node_registration_complete;
+
+	/*!
+	 * The union of all nodes' selection boxes.
+	 * Might be larger if big nodes are removed from the manager.
+	 */
+	aabb3f m_selection_box_union;
+
+	/*!
+	 * The smallest box in integer node coordinates that
+	 * contains all nodes' selection boxes.
+	 * Might be larger if big nodes are removed from the manager.
+	 */
+	core::aabbox3d<s16> m_selection_box_int_union;
+
+	/*!
+	 * NodeResolver instances to notify once node registration has finished.
+	 * Even constant NodeDefManager instances can register listeners.
+	 */
+	mutable std::vector<NodeResolver *> m_pending_resolve_callbacks;
 };
 
-IWritableNodeDefManager *createNodeDefManager();
+NodeDefManager *createNodeDefManager();
 
 class NodeResolver {
 public:
@@ -542,6 +743,6 @@ public:
 	u32 m_nnlistsizes_idx = 0;
 	std::vector<std::string> m_nodenames;
 	std::vector<size_t> m_nnlistsizes;
-	INodeDefManager *m_ndef = nullptr;
+	const NodeDefManager *m_ndef = nullptr;
 	bool m_resolve_done = false;
 };