elemdbm.h

3D Game Engine Design Source Code非常棒

#ifndef ELEMDBM_H
#define ELEMDBM_H

#include <iostream.h>
#include "element.h"

class mgcElementDBM
{
public:
	typedef void (*EFinput)(istream&,void*);
	typedef void (*EFoutput)(ostream&,const void*);
	typedef void (*EFreverse)(int,void*);
	typedef void (*EFcompact)(int,void*);
	typedef void (*EFconvert)(int,void*,void*);

	typedef struct _unresolvedconvert {
		const int* srctype;
		const int* trgtype;
		EFconvert convert_to;
		struct _unresolvedconvert* next;
	} UnresolvedConvert;

	typedef struct {
		const int* addrtype;		// address of variable defining the type
		const char* description;	// struct-type field description
		int memory_size;   			// size for memory representation
		int packed_size;   			// size for packed representation
		EFinput input;				// read element from input stream
		EFoutput output;			// write element to output stream
		EFreverse reverse;			// reorder bytes for current machine
		EFcompact pack;  			// pack struct-type for file storage
		EFcompact unpack;			// unpack struct-type for memory storage
		EFconvert* convert_to;		// conversions to other types
	} ElementRecord;

	static int CreateDataBase ();
	static void DestroyDataBase ();

	static int AddType (const ElementRecord& er);
	static int AddConvert (const int& srctype, const int& trgtype, EFconvert f);
	static int Type (const char* description);
	static int Valid (int type);
	static const char* Description (int type);
	static int MemorySize (int type);
	static int PackedSize (int type);

	// byte-ordering and reversal methods
	static int ByteOrder ();
	static void Reverse2 (int quantity, void* src);
	static void Reverse4 (int quantity, void* src);
	static void Reverse8 (int quantity, void* src);
	static int Reversible (int type);
	static int Reverse (int quantity, int type, void* src);

	// packing and unpacking methods for struct types
	static int Packable (int type);
	static int Pack (int quantity, int type, void* src);
	static int Unpackable (int type);
	static int Unpack (int quantity, int type, void* src);

	// conversions
	static int Convertible (int srctype, int trgtype);
	static int Convert (
		int quantity, int srctype, void* src, int trgtype, void* trg
	);

	static ElementRecord* record;
private:
	static int maxregistered;
	static int registered;
	static UnresolvedConvert* cnvlist;

// error handling
public:
	static int verbose;
	static unsigned error;
	static void Report (ostream& ostr);
private:
	static const unsigned allocation_failed;
	static const unsigned unknown_ordering;
	static const unsigned exceeded_maximum;
	static const char* message[3];
	static int Number (unsigned single_error);
	static void Report (unsigned single_error);
};

// automatic creation of data base
static int mgcElementDBM_create = mgcElementDBM::CreateDataBase();

#endif