tabmapindexblock.h

linux下一款GIS程序源码

// tabmapindexblock.h: interface for the TABMAPIndexBlock class.
//
/*---------------------------------------------------------------------
 *                      class TABMAPIndexBlock
 *
 * Class to handle Read/Write operation on .MAP Index Blocks (Type 01)
 *--------------------------------------------------------------------*/

#ifndef  TABMAPIndexBlock_H
#define  TABMAPIndexBlock_H

#include "ugkglobal.h"
#include "tabrawbinblock.h"
#include "tabbinblockmanager.h"

class TABMAPIndexBlock : public TABRawBinBlock  
{
protected:
	int         m_numEntries;
	TABMAPIndexEntry m_asEntries[TAB_MAX_ENTRIES_INDEX_BLOCK];

    int         ReadNextEntry(TABMAPIndexEntry *psEntry);
    int         WriteNextEntry(TABMAPIndexEntry *psEntry);

    // Use these to keep track of current block's MBR
    UGKInt32      m_nMinX;
    UGKInt32      m_nMinY;
    UGKInt32      m_nMaxX;
    UGKInt32      m_nMaxY;

	TABBinBlockManager *m_poBlockManagerRef;  //有何用??

    // Info about child currently loaded
    TABMAPIndexBlock *m_poCurChild;
    int         m_nCurChildIndex;  //标志当前加载的子索引块在本索引块中的位置
    // Also need to know about its parent
    TABMAPIndexBlock *m_poParentRef;

    int         ReadAllEntries();
public:
	TABMAPIndexBlock(TABAccess eAccessMode = TABRead);
	virtual ~TABMAPIndexBlock();

    virtual int InitBlockFromData(UGKByte *pabyBuf, int nSize, 
                              UGKBool bMakeCopy = TRUE,
                              FILE *fpSrc = NULL, int nOffset = 0);
    virtual int InitNewBlock(FILE *fpSrc, int nBlockSize, int nFileOffset=0);
    virtual int CommitToFile();

	virtual int GetBlockClass() { return TABMAP_INDEX_BLOCK; };

    int         GetNumFreeEntries();
    int         GetNumEntries()         {return m_numEntries;};
    TABMAPIndexEntry *GetEntry( int iIndex );
    int         AddEntry(UGKInt32 XMin, UGKInt32 YMin,
                         UGKInt32 XMax, UGKInt32 YMax,
                         UGKInt32 nBlockPtr,
                         UGKBool bAddInThisNodeOnly=FALSE);
    int         GetCurMaxDepth();
    void        GetMBR(UGKInt32 &nXMin, UGKInt32 &nYMin, 
                       UGKInt32 &nXMax, UGKInt32 &nYMax);
    UGKInt32      GetNodeBlockPtr() { return GetStartAddress();};


    void        SetMAPBlockManagerRef(TABBinBlockManager *poBlockMgr);
    void        SetParentRef(TABMAPIndexBlock *poParent);
    void        SetCurChildRef(TABMAPIndexBlock *poChild, int nChildIndex);

    int         GetCurChildIndex() { return m_nCurChildIndex; }
    TABMAPIndexBlock *GetCurChild() { return m_poCurChild; }
    TABMAPIndexBlock *GetParentRef() { return m_poParentRef; } 

    int         SplitNode(int nNewEntryX, int nNewEntryY);
    int         SplitRootNode(int nNewEntryX, int nNewEntryY);
    void        UpdateCurChildMBR(UGKInt32 nXMin, UGKInt32 nYMin,
                                  UGKInt32 nXMax, UGKInt32 nYMax,
                                  UGKInt32 nBlockPtr);
    void        RecomputeMBR();
    int         InsertEntry(UGKInt32 XMin, UGKInt32 YMin,
                            UGKInt32 XMax, UGKInt32 YMax, UGKInt32 nBlockPtr);

    virtual void Dump(FILE *fpOut = NULL);

};

#endif