dted_ptstream.c

把dem文件转换为dted格式文件的程序

/******************************************************************************
 * $Id: dted_ptstream.c 10646 2007-01-18 02:38:10Z warmerdam $
 *
 * Project:  DTED Translator
 * Purpose:  DTED Point Stream Writer.
 * Author:   Frank Warmerdam, [e-mail]
 *
 ******************************************************************************
 * Copyright (c) 2001, 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 "dted_api.h"
#include <sys/types.h>
#include <sys/stat.h>

CPL_CVSID("$Id: dted_ptstream.c 10646 2007-01-18 02:38:10Z warmerdam $");

typedef struct {
    char     *pszFilename;
    DTEDInfo *psInfo;

    GInt16 **papanProfiles;

    int    nLLLong;
    int    nLLLat;
} DTEDCachedFile;

typedef struct {
    int nLevel;
    char *pszPath;

    double  dfPixelSize;

    int nOpenFiles;
    DTEDCachedFile *pasCF;

    int nLastFile;

    char *apszMetadata[DTEDMD_MAX+1];
} DTEDPtStream;

/************************************************************************/
/*                         DTEDCreatePtStream()                         */
/************************************************************************/

void *DTEDCreatePtStream( const char *pszPath, int nLevel )

{
    DTEDPtStream *psStream;
    int          i;
	struct _stat buf;

/* -------------------------------------------------------------------- */
/*      Does the target directory already exist?  If not try to         */
/*      create it.                                                      */
/* -------------------------------------------------------------------- */

    if( _stat( pszPath, &buf ) != 0 )
    {
        if( VSIMkdir( pszPath, 0755 ) != 0 )
        {
#ifndef AVOID_CPL
            CPLError( CE_Failure, CPLE_OpenFailed,
                      "Unable to find, or create directory `%s'.",
                      pszPath );
#endif
            return NULL;
        }
    }

/* -------------------------------------------------------------------- */
/*      Create the stream and initialize it.                            */
/* -------------------------------------------------------------------- */

    psStream = (DTEDPtStream *) CPLCalloc( sizeof(DTEDPtStream), 1 );
    psStream->nLevel = nLevel;
    psStream->pszPath = CPLStrdup( pszPath );
    psStream->nOpenFiles = 0;
    psStream->pasCF = NULL;
    psStream->nLastFile = -1;

    for( i = 0; i < DTEDMD_MAX+1; i++ )
        psStream->apszMetadata[i] = NULL;

    if( nLevel == 0 )
        psStream->dfPixelSize = 1.0 / 120.0;
    else if( nLevel == 1 )
        psStream->dfPixelSize = 1.0 / 1200.0;
    else if( nLevel == 2 )
        psStream->dfPixelSize = 1.0 / 3600.0;
    else
        psStream->dfPixelSize = 1.0 / 3600.0;
    
    return (void *) psStream;
}

/************************************************************************/
/*                        DTEDPtStreamNewTile()                         */
/*                                                                      */
/*      Create a new DTED file file, add it to our list, and make it    */
/*      "current".                                                      */
/************************************************************************/

static int DTEDPtStreamNewTile( DTEDPtStream *psStream, 
                                int nCrLong, int nCrLat )

{
    DTEDInfo        *psInfo;
    char            szFile[128];
    char            chNSHemi, chEWHemi;
    char            *pszFullFilename;
	char            pszSubDir[64];
	char            pszSubDirFile[256];
	char            pszPathDir[256];
    const char      *pszError;
	struct _stat buf;

    /* work out filename */
    if( nCrLat < 0 )
        chNSHemi = 's';
    else
        chNSHemi = 'n';

    if( nCrLong < 0 )
        chEWHemi = 'w';
    else
        chEWHemi = 'e';


	memset(pszSubDir,0,sizeof(char));
	memset(pszSubDirFile,0,sizeof(char));
	memset(pszPathDir,0,sizeof(char));
	memset(szFile,0,sizeof(char));

	sprintf( pszSubDir, "%c%03d",chEWHemi, ABS(nCrLong));
	sprintf( szFile, "%c%02d.dt%d", chNSHemi, ABS(nCrLat),psStream->nLevel );
	sprintf( pszPathDir, "%s\\%s", psStream->pszPath, pszSubDir );

	if( _stat( pszPathDir, &buf ) != 0 )
	{
		if( VSIMkdir( pszPathDir, 0755 ) != 0 )
		{
#ifndef AVOID_CPL
			CPLError( CE_Failure, CPLE_OpenFailed,
				"Unable to find, or create directory `%s'.",
				pszPathDir );
#endif
			return -1;
		}
	}

    pszFullFilename = 
        CPLStrdup(CPLFormFilename(pszPathDir, szFile, NULL ));


	/* -------------------------------------------------------------------- */
	/*      Does the target directory already exist?  If not try to         */
	/*      create it.                                                      */
	/* -------------------------------------------------------------------- */


    /* create the dted file */
    pszError = DTEDCreate( pszFullFilename, psStream->nLevel, 
                           nCrLat, nCrLong );
    if( pszError != NULL )
    {
#ifndef AVOID_CPL
        CPLError( CE_Failure, CPLE_OpenFailed, 
                  "Failed to create DTED file `%s'.\n%s", 
                  pszFullFilename, pszError );
#endif
        return FALSE;
    }

    psInfo = DTEDOpen( pszFullFilename, "rb+", FALSE );

    if( psInfo == NULL )
    {
        CPLFree( pszFullFilename );
        return FALSE;
    }


    /* add cached file to stream */
    psStream->nOpenFiles++;
    psStream->pasCF = 
        CPLRealloc(psStream->pasCF, 
                   sizeof(DTEDCachedFile)*psStream->nOpenFiles);

	sprintf( pszSubDirFile, "%s\\%s",pszSubDir, szFile);

	printf("创建文件 [ %s ]\n",pszSubDirFile);

    psStream->pasCF[psStream->nOpenFiles-1].psInfo = psInfo;
    psStream->pasCF[psStream->nOpenFiles-1].papanProfiles =
        CPLCalloc(sizeof(GInt16*),psInfo->nXSize);
    psStream->pasCF[psStream->nOpenFiles-1].pszFilename = pszFullFilename;
    psStream->pasCF[psStream->nOpenFiles-1].nLLLat = nCrLat;
    psStream->pasCF[psStream->nOpenFiles-1].nLLLong = nCrLong;

    psStream->nLastFile = psStream->nOpenFiles-1;

	memset(pszSubDir,0,sizeof(char));
	memset(pszSubDirFile,0,sizeof(char));
	memset(pszPathDir,0,sizeof(char));
	memset(szFile,0,sizeof(char));


    return TRUE;
}

/************************************************************************/
/*                           DTEDWritePtLL()                            */
/************************************************************************/

static int DTEDWritePtLL( DTEDPtStream *psStream, 
                          DTEDCachedFile *psCF, 
                          double dfLong, double dfLat, double dfElev )

{
/* -------------------------------------------------------------------- */
/*      Determine what profile this belongs in, and initialize the      */
/*      profile if it doesn't already exist.                            */
/* -------------------------------------------------------------------- */
    DTEDInfo *psInfo = psCF->psInfo;
    int iProfile, i, iRow;

    iProfile = (int) ((dfLong - psInfo->dfULCornerX) / psInfo->dfPixelSizeX);
    iProfile = MAX(0,MIN(psInfo->nXSize-1,iProfile));

    if( psCF->papanProfiles[iProfile] == NULL )
    {
        psCF->papanProfiles[iProfile] = 
            CPLMalloc(sizeof(GInt16) * psInfo->nYSize);

        for( i = 0; i < psInfo->nYSize; i++ )
            psCF->papanProfiles[iProfile][i] = DTED_NODATA_VALUE;
    }

/* -------------------------------------------------------------------- */
/*      Establish where we fit in the profile.                          */
/* -------------------------------------------------------------------- */
    iRow = (int) ((psInfo->dfULCornerY-dfLat) / psInfo->dfPixelSizeY);
    iRow = MAX(0,MIN(psInfo->nYSize-1,iRow));

    psCF->papanProfiles[iProfile][iRow] = (GInt16) floor(dfElev+0.5);

    return TRUE;
}

/************************************************************************/
/*                            DTEDWritePt()                             */
/*                                                                      */
/*      Write a single point out, creating a new file if necessary      */
/*      to hold it.                                                     */
/************************************************************************/

int DTEDWritePt( void *hStream, double dfLong, double dfLat, double dfElev )

{
    DTEDPtStream *psStream = (DTEDPtStream *) hStream;
    int          i;
    DTEDInfo     *psInfo;
    int          bOnBoundary = FALSE;

/* -------------------------------------------------------------------- */
/*      Determine if we are in a boundary region ... that is in the     */
/*      area of the edge "pixel" that is shared with adjacent           */
/*      tiles.                                                          */
/* -------------------------------------------------------------------- */
    if( (floor(dfLong - 0.5*psStream->dfPixelSize) 
         != floor(dfLong + 0.5*psStream->dfPixelSize))
        || (floor(dfLat - 0.5*psStream->dfPixelSize) 
            != floor(dfLat + 0.5*psStream->dfPixelSize)) )
    {
        bOnBoundary = TRUE;
        psStream->nLastFile = -1;
    }

/* ==================================================================== */
/*      Handle case where the tile is not on a boundary.  We only       */
/*      need one output tile.                                           */
/* ==================================================================== */
/* -------------------------------------------------------------------- */
/*      Is the last file used still applicable?                         */
/* -------------------------------------------------------------------- */
    if( !bOnBoundary )
    {
        if( psStream->nLastFile != -1 )
        {
            psInfo = psStream->pasCF[psStream->nLastFile].psInfo;
            
            if( dfLat > psInfo->dfULCornerY
                || dfLat < psInfo->dfULCornerY - 1.0 - psInfo->dfPixelSizeY
                || dfLong < psInfo->dfULCornerX
                || dfLong > psInfo->dfULCornerX + 1.0 + psInfo->dfPixelSizeX )
                psStream->nLastFile = -1;
        }

/* -------------------------------------------------------------------- */
/*      Search for the file to write to.                                */
/* -------------------------------------------------------------------- */
        for( i = 0; i < psStream->nOpenFiles && psStream->nLastFile == -1; i++ )
        {
            psInfo = psStream->pasCF[i].psInfo;
            
            if( !(dfLat > psInfo->dfULCornerY
                  || dfLat < psInfo->dfULCornerY - 1.0 - psInfo->dfPixelSizeY
                  || dfLong < psInfo->dfULCornerX
                  || dfLong > psInfo->dfULCornerX + 1.0 + psInfo->dfPixelSizeX) )
            {
                psStream->nLastFile = i;
            }
        }

/* -------------------------------------------------------------------- */
/*      If none found, create a new file.                               */
/* -------------------------------------------------------------------- */
        if( psStream->nLastFile == -1 )