Class PathNodePool

Source/Utils/micropather.h:272–342

Memory manager for the PathNodes. */

	/* Memory manager for the PathNodes. */
	class PathNodePool
	{
	public:
		PathNodePool( unsigned allocate, unsigned typicalAdjacent );
		~PathNodePool();

		// Free all the memory except the first block. Resets all memory.
		void Clear();

		// Essentially:
		// pNode = Find();
		// if ( !pNode )
		//		pNode = New();
		//
		// Get the PathNode associated with this state. If the PathNode already
		// exists (allocated and is on the current frame), it will be returned. 
		// Else a new PathNode is allocated and returned. The returned object
		// is always fully initialized.
		//
		// NOTE: if the pathNode exists (and is current) all the initialization
		//       parameters are ignored.
		PathNode* GetPathNode(		unsigned frame,
									cPosition _state,
									float _costFromStart, 
									float _estToGoal, 
									PathNode* _parent );

		// Get a pathnode that is already in the pool.
		PathNode* FetchPathNode( cPosition state );

		// Store stuff in cache
		bool PushCache( const NodeCost* nodes, int nNodes, int* start );

		// Get neighbors from the cache
		// Note - always access this with an offset. Can get re-allocated.
		void GetCache( int start, int nNodes, NodeCost* nodes );

		// Return all the allocated states. Useful for visuallizing what
		// the pather is doing.
		void AllStates( unsigned frame, MP_VECTOR< cPosition >* stateVec );

	private:
		struct Block
		{
			Block* nextBlock;
			PathNode pathNode[1];
		};

		unsigned Hash( cPosition voidval );
		unsigned HashSize() const	{ return 1<<hashShift; }
		unsigned HashMask()	const	{ return ((1<<hashShift)-1); }
		void AddPathNode( unsigned key, PathNode* p );
		Block* NewBlock();
		PathNode* Alloc();

		PathNode**	hashTable;
		Block*		firstBlock;
		Block*		blocks;