ogrutils.cpp

mitab,读取MapInfo的地图文件

/******************************************************************************
 * $Id: ogrutils.cpp 11034 2007-03-21 04:38:04Z mloskot $
 *
 * Project:  OpenGIS Simple Features Reference Implementation
 * Purpose:  Utility functions for OGR classes, including some related to
 *           parsing well known text format vectors.
 * Author:   Frank Warmerdam, [e-mail]
 *
 ******************************************************************************
 * Copyright (c) 1999, Frank Warmerdam
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 ****************************************************************************/

#include <ctype.h>

#include "ogr_geometry.h"
#include "ogr_p.h"

#ifdef OGR_ENABLED
# include "ogrsf_frmts.h"
#endif /* OGR_ENABLED */

CPL_CVSID("$Id: ogrutils.cpp 11034 2007-03-21 04:38:04Z mloskot $");

/************************************************************************/
/*                         OGRTrimExtraZeros()                          */
/************************************************************************/

static void OGRTrimExtraZeros( char *pszTarget )

{
    int i = 0;

    while( pszTarget[i] != '\0' ) 
        i++;

/* -------------------------------------------------------------------- */
/*      Trim trailing 000001's as they are likely roundoff error.       */
/* -------------------------------------------------------------------- */
    if( i > 10
        && pszTarget[i-1] == '1' 
        && pszTarget[i-2] == '0' 
        && pszTarget[i-3] == '0' 
        && pszTarget[i-4] == '0' 
        && pszTarget[i-5] == '0' 
        && pszTarget[i-6] == '0' )
    {
        pszTarget[--i] = '\0';
    }

/* -------------------------------------------------------------------- */
/*      Trim trailing zeros.                                            */
/* -------------------------------------------------------------------- */
    while( i > 2 && pszTarget[i-1] == '0' && pszTarget[i-2] != '.' )
    {
        pszTarget[--i] = '\0';
    }
}

/************************************************************************/
/*                        OGRMakeWktCoordinate()                        */
/*                                                                      */
/*      Format a well known text coordinate, trying to keep the         */
/*      ASCII representation compact, but accurate.  These rules        */
/*      will have to tighten up in the future.                          */
/*                                                                      */
/*      Currently a new point should require no more than 64            */
/*      characters barring the X or Y value being extremely large.      */
/************************************************************************/

void OGRMakeWktCoordinate( char *pszTarget, double x, double y, double z, 
                           int nDimension )

{
    char  szX[40], szY[40], szZ[40];

    szZ[0] = '\0';

    if( x == (int) x && y == (int) y && z == (int) z )
    {
        sprintf( szX, "%d", (int) x );
        sprintf( szY, " %d", (int) y );
    }
    else
    {
        sprintf( szX, "%.15f", x );
        OGRTrimExtraZeros( szX );
        sprintf( szY, " %.15f", y );
        OGRTrimExtraZeros( szY );
    }

    if( nDimension == 3 )
    {
        if( z == (int) z )
            sprintf( szZ, " %d", (int) z );
        else
        {
            sprintf( szZ, " %.15f", z );
            OGRTrimExtraZeros( szZ );
        }
    }
            
    if( strlen(szX) + strlen(szY) + strlen(szZ) > 75 )
    {
        strcpy( szX, "0" );
        strcpy( szY, "0" );
        if( nDimension == 3 )
            strcpy( szZ, "0" );

#ifdef DEBUG
        CPLDebug( "OGR", 
                  "Yow!  Got this big result in OGRMakeWktCoordinate()\n"
                  "%s %s %s", 
                  szX, szY, szZ );
#endif
    }

    strcpy( pszTarget, szX );
    strcat( pszTarget, szY );
    strcat( pszTarget, szZ );
}

/************************************************************************/
/*                          OGRWktReadToken()                           */
/*                                                                      */
/*      Read one token or delimeter and put into token buffer.  Pre     */
/*      and post white space is swallowed.                              */
/************************************************************************/

const char *OGRWktReadToken( const char * pszInput, char * pszToken )

{
    if( pszInput == NULL )
        return NULL;
    
/* -------------------------------------------------------------------- */
/*      Swallow pre-white space.                                        */
/* -------------------------------------------------------------------- */
    while( *pszInput == ' ' || *pszInput == '\t' )
        pszInput++;

/* -------------------------------------------------------------------- */
/*      If this is a delimeter, read just one character.                */
/* -------------------------------------------------------------------- */
    if( *pszInput == '(' || *pszInput == ')' || *pszInput == ',' )
    {
        pszToken[0] = *pszInput;
        pszToken[1] = '\0';
        
        pszInput++;
    }

/* -------------------------------------------------------------------- */
/*      Or if it alpha numeric read till we reach non-alpha numeric     */
/*      text.                                                           */
/* -------------------------------------------------------------------- */
    else
    {
        int             iChar = 0;
        
        while( iChar < OGR_WKT_TOKEN_MAX-1
               && ((*pszInput >= 'a' && *pszInput <= 'z')
                   || (*pszInput >= 'A' && *pszInput <= 'Z')
                   || (*pszInput >= '0' && *pszInput <= '9')
                   || *pszInput == '.' 
                   || *pszInput == '+' 
                   || *pszInput == '-') )
        {
            pszToken[iChar++] = *(pszInput++);
        }

        pszToken[iChar++] = '\0';
    }

/* -------------------------------------------------------------------- */
/*      Eat any trailing white space.                                   */
/* -------------------------------------------------------------------- */
    while( *pszInput == ' ' || *pszInput == '\t' )
        pszInput++;

    return( pszInput );
}

/************************************************************************/
/*                          OGRWktReadPoints()                          */
/*                                                                      */
/*      Read a point string.  The point list must be contained in       */
/*      brackets and each point pair separated by a comma.              */
/************************************************************************/

const char * OGRWktReadPoints( const char * pszInput,
                               OGRRawPoint ** ppaoPoints, double **ppadfZ,
                               int * pnMaxPoints,
                               int * pnPointsRead )

{
    const char *pszOrigInput = pszInput;
    *pnPointsRead = 0;

    if( pszInput == NULL )
        return NULL;
    
/* -------------------------------------------------------------------- */
/*      Eat any leading white space.                                    */
/* -------------------------------------------------------------------- */
    while( *pszInput == ' ' || *pszInput == '\t' )
        pszInput++;

/* -------------------------------------------------------------------- */
/*      If this isn't an opening bracket then we have a problem!        */
/* -------------------------------------------------------------------- */
    if( *pszInput != '(' )
    {
        CPLDebug( "OGR",
                  "Expected '(', but got %s in OGRWktReadPoints().\n",
                  pszInput );
                  
        return pszInput;
    }

    pszInput++;

/* ==================================================================== */
/*      This loop reads a single point.  It will continue till we       */
/*      run out of well formed points, or a closing bracket is          */
/*      encountered.                                                    */
/* ==================================================================== */
    char        szDelim[OGR_WKT_TOKEN_MAX];
    
    do {
/* -------------------------------------------------------------------- */
/*      Read the X and Y values, verify they are numeric.               */
/* -------------------------------------------------------------------- */
        char    szTokenX[OGR_WKT_TOKEN_MAX];
        char    szTokenY[OGR_WKT_TOKEN_MAX];

        pszInput = OGRWktReadToken( pszInput, szTokenX );
        pszInput = OGRWktReadToken( pszInput, szTokenY );

        if( (!isdigit(szTokenX[0]) && szTokenX[0] != '-' && szTokenX[0] != '.' )
            || (!isdigit(szTokenY[0]) && szTokenY[0] != '-' && szTokenY[0] != '.') )
            return NULL;

/* -------------------------------------------------------------------- */
/*      Do we need to grow the point list to hold this point?           */
/* -------------------------------------------------------------------- */
        if( *pnPointsRead == *pnMaxPoints )
        {
            *pnMaxPoints = *pnMaxPoints * 2 + 10;
            *ppaoPoints = (OGRRawPoint *)
                CPLRealloc(*ppaoPoints, sizeof(OGRRawPoint) * *pnMaxPoints);