avc_binwr.c

支持各种栅格图像和矢量图像读取的库

      default:
        /* Other file types don't need a header */
        bHeader = FALSE;
    }

    /*-----------------------------------------------------------------
     * Write a header only if applicable.
     *----------------------------------------------------------------*/
    if (bHeader)
        nStatus = _AVCBinWriteHeader(psFile->psRawBinFile, &sHeader,
                                     psFile->eCoverType);

    /*-----------------------------------------------------------------
     * Write a header for the index file... it is identical to the main
     * file's header.
     *----------------------------------------------------------------*/
    if (nStatus == 0 && bHeader && psFile->psIndexFile)
        nStatus = _AVCBinWriteHeader(psFile->psIndexFile, &sHeader,
                                     psFile->eCoverType);

    return nStatus;
}

/**********************************************************************
 *                          AVCBinWriteClose()
 *
 * Close a coverage file opened for wirting, and release all memory 
 * (object strcut., buffers, etc.) associated with this file.
 **********************************************************************/

void    AVCBinWriteClose(AVCBinFile *psFile)
{
    if (psFile->eFileType == AVCFileTABLE)
    {
        _AVCBinWriteCloseTable(psFile);
        return;
    }

    /*-----------------------------------------------------------------
     * Write the file size (nbr of 2 byte words) in the header at 
     * byte 24 in the 100 byte header (only if applicable)
     * (And write the same value at byte 2-5 in the first header of PC Cover)
     *----------------------------------------------------------------*/
    if (psFile->psRawBinFile &&
        (psFile->eFileType == AVCFileARC ||
         psFile->eFileType == AVCFilePAL ||
         psFile->eFileType == AVCFileRPL ||
         psFile->eFileType == AVCFileLAB ||
         psFile->eFileType == AVCFileCNT ||
         psFile->eFileType == AVCFileTXT ||
         psFile->eFileType == AVCFileTX6 ||
         (psFile->eFileType == AVCFileTOL && 
          psFile->nPrecision == AVC_DOUBLE_PREC) ) )
    {
        GInt32 n32Size;
        n32Size = psFile->psRawBinFile->nCurPos/2;

        if (psFile->eCoverType == AVCCoverPC)
        {
            /* PC Cover... Pad to multiple of 512 bytes and write 2 headers
             * extra bytes at EOF are not included in the size written in
             * header.
             * The first 256 bytes header is not counted in the file size 
             * written in both headers
             */
            n32Size -= 128;  /* minus 256 bytes */

            if (psFile->psRawBinFile->nCurPos%512 != 0)
                AVCRawBinWriteZeros(psFile->psRawBinFile, 
                                    512 - psFile->psRawBinFile->nCurPos%512);
                
            VSIFSeek(psFile->psRawBinFile->fp, 2, SEEK_SET);
            AVCRawBinWriteInt32(psFile->psRawBinFile, n32Size);

            VSIFSeek(psFile->psRawBinFile->fp, 256+24, SEEK_SET);
            AVCRawBinWriteInt32(psFile->psRawBinFile, n32Size);
        }
        else
        {
            /* V7 Cover ... only 1 header */
            VSIFSeek(psFile->psRawBinFile->fp, 24, SEEK_SET);
            AVCRawBinWriteInt32(psFile->psRawBinFile, n32Size);
        }
    }
        
    AVCRawBinClose(psFile->psRawBinFile);
    psFile->psRawBinFile = NULL;

    /*-----------------------------------------------------------------
     * Same for the index file if it exists.
     *----------------------------------------------------------------*/
    if (psFile->psIndexFile)
    {
        GInt32 n32Size;
        n32Size = psFile->psIndexFile->nCurPos/2;

        if (psFile->eCoverType == AVCCoverPC)
        {
            /* PC Cover... Pad to multiple of 512 bytes and write 2 headers
             * extra bytes at EOF are not included in the size written in
             * header
             */
            n32Size -= 128;  /* minus 256 bytes */

            if (psFile->psIndexFile->nCurPos%512 != 0)
                AVCRawBinWriteZeros(psFile->psIndexFile, 
                                    512 - psFile->psIndexFile->nCurPos%512);
                
            VSIFSeek(psFile->psIndexFile->fp, 2, SEEK_SET);
            AVCRawBinWriteInt32(psFile->psIndexFile, n32Size);

            VSIFSeek(psFile->psIndexFile->fp, 256+24, SEEK_SET);
            AVCRawBinWriteInt32(psFile->psIndexFile, n32Size);
        }
        else
        {
            /* V7 Cover ... only 1 header */
            VSIFSeek(psFile->psIndexFile->fp, 24, SEEK_SET);
            AVCRawBinWriteInt32(psFile->psIndexFile, n32Size);
        }

        AVCRawBinClose(psFile->psIndexFile);
        psFile->psIndexFile = NULL;
    }

    CPLFree(psFile->pszFilename);

    CPLFree(psFile);
}



/**********************************************************************
 *                          _AVCBinWriteIndexEntry()
 *
 * (This function is for internal library use... the index entries
 * are automatically handled by the AVCBinWrite*() functions)
 *
 * Write an Index Entry at the current position in the file.
 *
 * Position is relative to the beginning of the file, including the header.
 * Both position and size are specified in number of 2 byte words.
 *
 * Returns 0 on success or -1 on error.
 **********************************************************************/
int _AVCBinWriteIndexEntry(AVCRawBinFile *psFile, 
                           int nPosition, int nSize)
{
    AVCRawBinWriteInt32(psFile, nPosition);
    AVCRawBinWriteInt32(psFile, nSize);

    if (CPLGetLastErrorNo() != 0)
        return -1;

    return 0;
}

/**********************************************************************
 *                          AVCBinWriteObject()
 *
 * Write a CNT (Polygon Centroid) structure to the fin object to a 
 * coverage file.
 *
 * Simply redirects the call to the right function based on the value
 * of psFile->eFileType.
 *
 * Returns 0 on success or -1 on error.
 *
 * If a problem happens, then CPLError() will be called by the lower-level
 * functions and CPLGetLastErrorNo() can be used to find out what happened.
 **********************************************************************/
int AVCBinWriteObject(AVCBinFile *psFile, void *psObj)
{
    int nStatus = 0;
    switch(psFile->eFileType)
    {
      case AVCFileARC:
        nStatus = AVCBinWriteArc(psFile, (AVCArc *)psObj);
        break;
      case AVCFilePAL:
      case AVCFileRPL:
        nStatus = AVCBinWritePal(psFile, (AVCPal *)psObj);
        break;
      case AVCFileCNT:
        nStatus = AVCBinWriteCnt(psFile, (AVCCnt *)psObj);
        break;
      case AVCFileLAB:
        nStatus = AVCBinWriteLab(psFile, (AVCLab *)psObj);
        break;
      case AVCFileTOL:
        nStatus = AVCBinWriteTol(psFile, (AVCTol *)psObj);
        break;
      case AVCFilePRJ:
        nStatus = AVCBinWritePrj(psFile, (char **)psObj);
        break;
      case AVCFileTXT:
      case AVCFileTX6:
        nStatus = AVCBinWriteTxt(psFile, (AVCTxt *)psObj);
        break;
      case AVCFileRXP:
        nStatus = AVCBinWriteRxp(psFile, (AVCRxp *)psObj);
        break;
      case AVCFileTABLE:
        nStatus = AVCBinWriteTableRec(psFile, (AVCField *)psObj);
        break;
      default:
        CPLError(CE_Failure, CPLE_IllegalArg,
                 "AVCBinWriteObject(): Unsupported file type!");
        nStatus = -1;
    }

    return nStatus;
}


/*=====================================================================
 *                              ARC
 *====================================================================*/

/**********************************************************************
 *                          _AVCBinWriteArc()
 *
 * (This function is for internal library use... external calls should
 * go to AVCBinWriteNextArc() instead)
 *
 * Write an Arc structure to the file.
 *
 * The contents of the psArc structure is assumed to be valid... this
 * function performs no validation on the consistency of what it is 
 * given as input.
 *
 * Returns 0 on success or -1 on error.
 **********************************************************************/
int _AVCBinWriteArc(AVCRawBinFile *psFile, AVCArc *psArc,
                    int nPrecision, AVCRawBinFile *psIndexFile)
{
    int         i, nRecSize, nCurPos;

    nCurPos = psFile->nCurPos/2;  /* Value in 2 byte words */

    AVCRawBinWriteInt32(psFile, psArc->nArcId);
    if (CPLGetLastErrorNo() != 0)
        return -1;

    /*-----------------------------------------------------------------
     * Record size is expressed in 2 byte words, and does not count the
     * first 8 bytes of the ARC entry.
     *----------------------------------------------------------------*/
    nRecSize = (6 * 4 + psArc->numVertices*2 * 
                ((nPrecision == AVC_SINGLE_PREC)? 4 : 8)) / 2;
    AVCRawBinWriteInt32(psFile, nRecSize);
    AVCRawBinWriteInt32(psFile, psArc->nUserId);
    AVCRawBinWriteInt32(psFile, psArc->nFNode);
    AVCRawBinWriteInt32(psFile, psArc->nTNode);
    AVCRawBinWriteInt32(psFile, psArc->nLPoly);
    AVCRawBinWriteInt32(psFile, psArc->nRPoly);
    AVCRawBinWriteInt32(psFile, psArc->numVertices);

    if (nPrecision == AVC_SINGLE_PREC)
    {
        for(i=0; i<psArc->numVertices; i++)
        {
            AVCRawBinWriteFloat(psFile, (float)psArc->pasVertices[i].x);
            AVCRawBinWriteFloat(psFile, (float)psArc->pasVertices[i].y);
        }
    }
    else
    {
        for(i=0; i<psArc->numVertices; i++)
        {
            AVCRawBinWriteDouble(psFile, psArc->pasVertices[i].x);
            AVCRawBinWriteDouble(psFile, psArc->pasVertices[i].y);
        }

    }

    /*-----------------------------------------------------------------
     * Write index entry (arx.adf)
     *----------------------------------------------------------------*/
    if (psIndexFile)
    {
        _AVCBinWriteIndexEntry(psIndexFile, nCurPos, nRecSize);
    }

    if (CPLGetLastErrorNo() != 0)
        return -1;

    return 0;
}

/**********************************************************************
 *                          AVCBinWriteArc()
 *
 * Write the next Arc structure to the file.
 *
 * The contents of the psArc structure is assumed to be valid... this
 * function performs no validation on the consistency of what it is 
 * given as input.
 *
 * Returns 0 on success or -1 on error.
 *
 * If a problem happens, then CPLError() will be called by the lower-level
 * functions and CPLGetLastErrorNo() can be used to find out what happened.
 **********************************************************************/
int AVCBinWriteArc(AVCBinFile *psFile, AVCArc *psArc)
{
    if (psFile->eFileType != AVCFileARC)
        return -1;

    return _AVCBinWriteArc(psFile->psRawBinFile, psArc,
                           psFile->nPrecision, psFile->psIndexFile);
}


/*=====================================================================
 *                              PAL
 *====================================================================*/

/**********************************************************************
 *                          _AVCBinWritePal()
 *
 * (This function is for internal library use... external calls should
 * go to AVCBinWritePal() instead)
 *
 * Write a PAL (Polygon Arc List) structure to the file.
 *
 * The contents of the psPal structure is assumed to be valid... this
 * function performs no validation on the consistency of what it is 
 * given as input.
 *
 * Returns 0 on success or -1 on error.
 **********************************************************************/
int _AVCBinWritePal(AVCRawBinFile *psFile, AVCPal *psPal, 
                    int nPrecision, AVCRawBinFile *psIndexFile)
{
    int i, nRecSize, nCurPos;

    nCurPos = psFile->nCurPos/2;  /* Value in 2 byte words */

    AVCRawBinWriteInt32(psFile, psPal->nPolyId);
    if (CPLGetLastErrorNo() != 0)
        return -1;

    /*-----------------------------------------------------------------
     * Record size is expressed in 2 byte words, and does not count the
     * first 8 bytes of the PAL entry.
     *----------------------------------------------------------------*/
    nRecSize = ( 4 + psPal->numArcs*3 * 4 + 
                4 * ((nPrecision == AVC_SINGLE_PREC)? 4 : 8)) / 2;

    AVCRawBinWriteInt32(psFile, nRecSize);

    if (nPrecision == AVC_SINGLE_PREC)
    {
        AVCRawBinWriteFloat(psFile, (float)psPal->sMin.x);
        AVCRawBinWriteFloat(psFile, (float)psPal->sMin.y);
        AVCRawBinWriteFloat(psFile, (float)psPal->sMax.x);
        AVCRawBinWriteFloat(psFile, (float)psPal->sMax.y);
    }
    else
    {
        AVCRawBinWriteDouble(psFile, psPal->sMin.x);
        AVCRawBinWriteDouble(psFile, psPal->sMin.y);