shpopen.c

用于读取TAB、MIF、SHP文件的类

{
    int	       	nRecordOffset, i, nRecordSize=0;
    uchar	*pabyRec;
    int32	i32;

    psSHP->bUpdated = TRUE;

/* -------------------------------------------------------------------- */
/*      Ensure that shape object matches the type of the file it is     */
/*      being written to.                                               */
/* -------------------------------------------------------------------- */
    assert( psObject->nSHPType == psSHP->nShapeType 
            || psObject->nSHPType == SHPT_NULL );

/* -------------------------------------------------------------------- */
/*      Ensure that -1 is used for appends.  Either blow an             */
/*      assertion, or if they are disabled, set the shapeid to -1       */
/*      for appends.                                                    */
/* -------------------------------------------------------------------- */
    assert( nShapeId == -1 
            || (nShapeId >= 0 && nShapeId < psSHP->nRecords) );

    if( nShapeId != -1 && nShapeId >= psSHP->nRecords )
        nShapeId = -1;

/* -------------------------------------------------------------------- */
/*      Add the new entity to the in memory index.                      */
/* -------------------------------------------------------------------- */
    if( nShapeId == -1 && psSHP->nRecords+1 > psSHP->nMaxRecords )
    {
	psSHP->nMaxRecords =(int) ( psSHP->nMaxRecords * 1.3 + 100);

	psSHP->panRecOffset = (int *) 
            SfRealloc(psSHP->panRecOffset,sizeof(int) * psSHP->nMaxRecords );
	psSHP->panRecSize = (int *) 
            SfRealloc(psSHP->panRecSize,sizeof(int) * psSHP->nMaxRecords );
    }

/* -------------------------------------------------------------------- */
/*      Initialize record.                                              */
/* -------------------------------------------------------------------- */
    pabyRec = (uchar *) malloc(psObject->nVertices * 4 * sizeof(double) 
			       + psObject->nParts * 8 + 128);
    
/* -------------------------------------------------------------------- */
/*  Extract vertices for a Polygon or Arc.				*/
/* -------------------------------------------------------------------- */
    if( psObject->nSHPType == SHPT_POLYGON
        || psObject->nSHPType == SHPT_POLYGONZ
        || psObject->nSHPType == SHPT_POLYGONM
        || psObject->nSHPType == SHPT_ARC 
        || psObject->nSHPType == SHPT_ARCZ
        || psObject->nSHPType == SHPT_ARCM
        || psObject->nSHPType == SHPT_MULTIPATCH )
    {
	int32		nPoints, nParts;
	int    		i;

	nPoints = psObject->nVertices;
	nParts = psObject->nParts;

	_SHPSetBounds( pabyRec + 12, psObject );

	if( bBigEndian ) SwapWord( 4, &nPoints );
	if( bBigEndian ) SwapWord( 4, &nParts );

	ByteCopy( &nPoints, pabyRec + 40 + 8, 4 );
	ByteCopy( &nParts, pabyRec + 36 + 8, 4 );

        nRecordSize = 52;

        /*
         * Write part start positions.
         */
	ByteCopy( psObject->panPartStart, pabyRec + 44 + 8,
                  4 * psObject->nParts );
	for( i = 0; i < psObject->nParts; i++ )
	{
	    if( bBigEndian ) SwapWord( 4, pabyRec + 44 + 8 + 4*i );
            nRecordSize += 4;
	}

        /*
         * Write multipatch part types if needed.
         */
        if( psObject->nSHPType == SHPT_MULTIPATCH )
        {
            memcpy( pabyRec + nRecordSize, psObject->panPartType,
                    4*psObject->nParts );
            for( i = 0; i < psObject->nParts; i++ )
            {
                if( bBigEndian ) SwapWord( 4, pabyRec + nRecordSize );
                nRecordSize += 4;
            }
        }

        /*
         * Write the (x,y) vertex values.
         */
	for( i = 0; i < psObject->nVertices; i++ )
	{
	    ByteCopy( psObject->padfX + i, pabyRec + nRecordSize, 8 );
	    ByteCopy( psObject->padfY + i, pabyRec + nRecordSize + 8, 8 );

	    if( bBigEndian )
                SwapWord( 8, pabyRec + nRecordSize );
            
	    if( bBigEndian )
                SwapWord( 8, pabyRec + nRecordSize + 8 );

            nRecordSize += 2 * 8;
	}

        /*
         * Write the Z coordinates (if any).
         */
        if( psObject->nSHPType == SHPT_POLYGONZ
            || psObject->nSHPType == SHPT_ARCZ
            || psObject->nSHPType == SHPT_MULTIPATCH )
        {
            ByteCopy( &(psObject->dfZMin), pabyRec + nRecordSize, 8 );
            if( bBigEndian ) SwapWord( 8, pabyRec + nRecordSize );
            nRecordSize += 8;
            
            ByteCopy( &(psObject->dfZMax), pabyRec + nRecordSize, 8 );
            if( bBigEndian ) SwapWord( 8, pabyRec + nRecordSize );
            nRecordSize += 8;

            for( i = 0; i < psObject->nVertices; i++ )
            {
                ByteCopy( psObject->padfZ + i, pabyRec + nRecordSize, 8 );
                if( bBigEndian ) SwapWord( 8, pabyRec + nRecordSize );
                nRecordSize += 8;
            }
        }

        /*
         * Write the M values, if any.
         */
        if( psObject->bMeasureIsUsed
            && (psObject->nSHPType == SHPT_POLYGONM
            || psObject->nSHPType == SHPT_ARCM
#ifndef DISABLE_MULTIPATCH_MEASURE            
            || psObject->nSHPType == SHPT_MULTIPATCH
#endif            
            || psObject->nSHPType == SHPT_POLYGONZ
            || psObject->nSHPType == SHPT_ARCZ) )
        {
            ByteCopy( &(psObject->dfMMin), pabyRec + nRecordSize, 8 );
            if( bBigEndian ) SwapWord( 8, pabyRec + nRecordSize );
            nRecordSize += 8;
            
            ByteCopy( &(psObject->dfMMax), pabyRec + nRecordSize, 8 );
            if( bBigEndian ) SwapWord( 8, pabyRec + nRecordSize );
            nRecordSize += 8;

            for( i = 0; i < psObject->nVertices; i++ )
            {
                ByteCopy( psObject->padfM + i, pabyRec + nRecordSize, 8 );
                if( bBigEndian ) SwapWord( 8, pabyRec + nRecordSize );
                nRecordSize += 8;
            }
        }
    }

/* -------------------------------------------------------------------- */
/*  Extract vertices for a MultiPoint.					*/
/* -------------------------------------------------------------------- */
    else if( psObject->nSHPType == SHPT_MULTIPOINT
             || psObject->nSHPType == SHPT_MULTIPOINTZ
             || psObject->nSHPType == SHPT_MULTIPOINTM )
    {
	int32		nPoints;
	int    		i;

	nPoints = psObject->nVertices;

        _SHPSetBounds( pabyRec + 12, psObject );

	if( bBigEndian ) SwapWord( 4, &nPoints );
	ByteCopy( &nPoints, pabyRec + 44, 4 );
	
	for( i = 0; i < psObject->nVertices; i++ )
	{
	    ByteCopy( psObject->padfX + i, pabyRec + 48 + i*16, 8 );
	    ByteCopy( psObject->padfY + i, pabyRec + 48 + i*16 + 8, 8 );

	    if( bBigEndian ) SwapWord( 8, pabyRec + 48 + i*16 );
	    if( bBigEndian ) SwapWord( 8, pabyRec + 48 + i*16 + 8 );
	}

	nRecordSize = 48 + 16 * psObject->nVertices;

        if( psObject->nSHPType == SHPT_MULTIPOINTZ )
        {
            ByteCopy( &(psObject->dfZMin), pabyRec + nRecordSize, 8 );
            if( bBigEndian ) SwapWord( 8, pabyRec + nRecordSize );
            nRecordSize += 8;

            ByteCopy( &(psObject->dfZMax), pabyRec + nRecordSize, 8 );
            if( bBigEndian ) SwapWord( 8, pabyRec + nRecordSize );
            nRecordSize += 8;
            
            for( i = 0; i < psObject->nVertices; i++ )
            {
                ByteCopy( psObject->padfZ + i, pabyRec + nRecordSize, 8 );
                if( bBigEndian ) SwapWord( 8, pabyRec + nRecordSize );
                nRecordSize += 8;
            }
        }

        if( psObject->bMeasureIsUsed
            && (psObject->nSHPType == SHPT_MULTIPOINTZ
            || psObject->nSHPType == SHPT_MULTIPOINTM) )
        {
            ByteCopy( &(psObject->dfMMin), pabyRec + nRecordSize, 8 );
            if( bBigEndian ) SwapWord( 8, pabyRec + nRecordSize );
            nRecordSize += 8;

            ByteCopy( &(psObject->dfMMax), pabyRec + nRecordSize, 8 );
            if( bBigEndian ) SwapWord( 8, pabyRec + nRecordSize );
            nRecordSize += 8;
            
            for( i = 0; i < psObject->nVertices; i++ )
            {
                ByteCopy( psObject->padfM + i, pabyRec + nRecordSize, 8 );
                if( bBigEndian ) SwapWord( 8, pabyRec + nRecordSize );
                nRecordSize += 8;
            }
        }
    }

/* -------------------------------------------------------------------- */
/*      Write point.							*/
/* -------------------------------------------------------------------- */
    else if( psObject->nSHPType == SHPT_POINT
             || psObject->nSHPType == SHPT_POINTZ
             || psObject->nSHPType == SHPT_POINTM )
    {
	ByteCopy( psObject->padfX, pabyRec + 12, 8 );
	ByteCopy( psObject->padfY, pabyRec + 20, 8 );

	if( bBigEndian ) SwapWord( 8, pabyRec + 12 );
	if( bBigEndian ) SwapWord( 8, pabyRec + 20 );

        nRecordSize = 28;
        
        if( psObject->nSHPType == SHPT_POINTZ )
        {
            ByteCopy( psObject->padfZ, pabyRec + nRecordSize, 8 );
            if( bBigEndian ) SwapWord( 8, pabyRec + nRecordSize );
            nRecordSize += 8;
        }
        
        if( psObject->bMeasureIsUsed
            && (psObject->nSHPType == SHPT_POINTZ
            || psObject->nSHPType == SHPT_POINTM) )
        {
            ByteCopy( psObject->padfM, pabyRec + nRecordSize, 8 );
            if( bBigEndian ) SwapWord( 8, pabyRec + nRecordSize );
            nRecordSize += 8;
        }
    }

/* -------------------------------------------------------------------- */
/*      Not much to do for null geometries.                             */
/* -------------------------------------------------------------------- */
    else if( psObject->nSHPType == SHPT_NULL )
    {
        nRecordSize = 12;
    }

    else
    {
        /* unknown type */
        assert( FALSE );
    }

/* -------------------------------------------------------------------- */
/*      Establish where we are going to put this record. If we are      */
/*      rewriting and existing record, and it will fit, then put it     */
/*      back where the original came from.  Otherwise write at the end. */
/* -------------------------------------------------------------------- */
    if( nShapeId == -1 || psSHP->panRecSize[nShapeId] < nRecordSize-8 )
    {
        if( nShapeId == -1 )
            nShapeId = psSHP->nRecords++;

        psSHP->panRecOffset[nShapeId] = nRecordOffset = psSHP->nFileSize;
        psSHP->panRecSize[nShapeId] = nRecordSize-8;
        psSHP->nFileSize += nRecordSize;
    }
    else
    {
        nRecordOffset = psSHP->panRecOffset[nShapeId];
        psSHP->panRecSize[nShapeId] = nRecordSize-8;
    }
    
/* -------------------------------------------------------------------- */
/*      Set the shape type, record number, and record size.             */
/* -------------------------------------------------------------------- */
    i32 = nShapeId+1;					/* record # */
    if( !bBigEndian ) SwapWord( 4, &i32 );
    ByteCopy( &i32, pabyRec, 4 );

    i32 = (nRecordSize-8)/2;				/* record size */
    if( !bBigEndian ) SwapWord( 4, &i32 );
    ByteCopy( &i32, pabyRec + 4, 4 );

    i32 = psObject->nSHPType;				/* shape type */
    if( bBigEndian ) SwapWord( 4, &i32 );
    ByteCopy( &i32, pabyRec + 8, 4 );

/* -------------------------------------------------------------------- */
/*      Write out record.                                               */
/* -------------------------------------------------------------------- */
    if( fseek( psSHP->fpSHP, nRecordOffset, 0 ) != 0
        || fwrite( pabyRec, nRecordSize, 1, psSHP->fpSHP ) < 1 )
    {
#ifdef USE_CPL
        CPLError( CE_Failure, CPLE_FileIO, 
                "Error in fseek() or fwrite() writing object to .shp file." );
#endif
        free( pabyRec );
        return -1;
    }
    
    free( pabyRec );

/* -------------------------------------------------------------------- */
/*	Expand file wide bounds based on this shape.			*/
/* -------------------------------------------------------------------- */
    if( psSHP->adBoundsMin[0] == 0.0
        && psSHP->adBoundsMax[0] == 0.0
        && psSHP->adBoundsMin[1] == 0.0
        && psSHP->adBoundsMax[1] == 0.0 )
    {
        if( psObject->nSHPType == SHPT_NULL || psObject->nVertices == 0 )
        {
            psSHP->adBoundsMin[0] = psSHP->adBoundsMax[0] = 0.0;
            psSHP->adBoundsMin[1] = psSHP->adBoundsMax[1] = 0.0;
            psSHP->adBoundsMin[2] = psSHP->adBoundsMax[2] = 0.0;
            psSHP->adBoundsMin[3] = psSHP->adBoundsMax[3] = 0.0;
        }
        else
        {
            psSHP->adBoundsMin[0] = psSHP->adBoundsMax[0] = psObject->padfX[0];
            psSHP->adBoundsMin[1] = psSHP->adBoundsMax[1] = psObject->padfY[0];
            psSHP->adBoundsMin[2] = psSHP->adBoundsMax[2] = psObject->padfZ[0];
            psSHP->adBoundsMin[3] = psSHP->adBoundsMax[3] = psObject->padfM[0];
        }
    }

    for( i = 0; i < psObject->nVertices; i++ )