ptapi.c

GIS系统支持库Geospatial Data Abstraction Library代码.GDAL is a translator library for raster geospatial dat

	if (status == 0)
	{
	    for (i = 0; i < NPOINT; i++)
	    {
		if (PTXPoint[i].active == 0)
		{
		    /*
		     * Set pointID, Set point entry active, Store root Vgroup
		     * ID, Store sub Vgroup IDs, Store HDF-EOS file ID
		     */
		    pointID = i + idOffset;
		    PTXPoint[i].active = 1;
		    PTXPoint[i].IDTable = vgid[0];
		    PTXPoint[i].VIDTable[0] = vgid[1];
		    PTXPoint[i].VIDTable[1] = vgid[2];
		    PTXPoint[i].VIDTable[2] = vgid[3];
		    PTXPoint[i].fid = fid;
		    status = 0;
		    break;
		}
	    }
	}
    }


    return (pointID);

}


/*----------------------------------------------------------------------------|
|  BEGIN_PROLOG                                                               |
|                                                                             |
|  FUNCTION: PTchkptid                                                        |
|                                                                             |
|  DESCRIPTION: Checks for valid pointID and returns file ID, SDS ID, and     |
|               point Vgroup ID                                               |
|                                                                             |
|                                                                             |
|  Return Value    Type     Units     Description                             |
|  ============   ======  =========   =====================================   |
|  status         intn                return status (0) SUCCEED, (-1) FAIL    |
|                                                                             |
|  INPUTS:                                                                    |
|  pointID        int32               point structure ID                      |
|  routname       char                Name of routine calling PTchkptid       |
|                                                                             |
|  OUTPUTS:                                                                   |
|  fid            int32               File ID                                 |
|  sdInterfaceID  int32               SDS interface ID                        |
|  ptVgroupID     int32               point Vgroup ID                         |
|                                                                             |
|  NOTES:                                                                     |
|                                                                             |
|                                                                             |
|   Date     Programmer   Description                                         |
|  ======   ============  =================================================   |
|  Jun 96   Joel Gales    Original Programmer                                 |
|                                                                             |
|  END_PROLOG                                                                 |
-----------------------------------------------------------------------------*/
intn
PTchkptid(int32 pointID, char *routname,
	  int32 * fid, int32 * sdInterfaceID, int32 * ptVgroupID)
{
    intn            status = 0;	/* routine return status variable */

    uint8           access;	/* Read/Write access code */

    int32           idOffset = PTIDOFFSET;	/* Point ID offset */

    char            message1[] =
    "Invalid point id: %d in routine \"%s\".  ID must be >= %d and < %d.\n";
    char            message2[] =
    "Point id %d in routine \"%s\" not active.\n";


    /* Check for valid point id */
    /* ------------------------ */
    if (pointID < idOffset || pointID >= NPOINT + idOffset)
    {
	status = -1;
	HEpush(DFE_RANGE, "PTchkptid", __FILE__, __LINE__);
	HEreport(message1, pointID, routname, idOffset, NPOINT + idOffset);
    }
    else
    {
	/* Check for active point ID */
	/* ------------------------- */
	if (PTXPoint[pointID % idOffset].active == 0)
	{
	    status = -1;
	    HEpush(DFE_GENAPP, "PTchkptid", __FILE__, __LINE__);
	    HEreport(message2, pointID, routname);
	}
	else
	{

	    /* Get file and Point key */
	    /* ----------------------- */
	    status = EHchkfid(PTXPoint[pointID % idOffset].fid, " ", fid,
			      sdInterfaceID, &access);
	    *ptVgroupID = PTXPoint[pointID % idOffset].IDTable;
	}
    }
    return (status);

}


/*----------------------------------------------------------------------------|
|  BEGIN_PROLOG                                                               |
|                                                                             |
|  FUNCTION: PTnrecs                                                          |
|                                                                             |
|  DESCRIPTION: Returns the number of records in a level.                     |
|                                                                             |
|                                                                             |
|  Return Value    Type     Units     Description                             |
|  ============   ======  =========   =====================================   |
|  nrec           int32               Number of records in level              |
|                                                                             |
|  INPUTS:                                                                    |
|  pointID        int32               point structure ID                      |
|  level          int32               level number (0 - based)                |
|                                                                             |
|                                                                             |
|  OUTPUTS:                                                                   |
|             None                                                            |
|                                                                             |
|  NOTES:                                                                     |
|                                                                             |
|                                                                             |
|   Date     Programmer   Description                                         |
|  ======   ============  =================================================   |
|  Jun 96   Joel Gales    Original Programmer                                 |
|                                                                             |
|  END_PROLOG                                                                 |
-----------------------------------------------------------------------------*/
int32
PTnrecs(int32 pointID, int32 level)
{
    intn            status = 0;	/* routine return status variable */

    uint8           recChk;	/* Record check flag */

    int32           fid;	/* HDF-EOS file id */
    int32           sdInterfaceID;	/* HDF SDS interface ID */
    int32           idOffset = PTIDOFFSET;	/* Point ID offset */
    int32           ptVgrpID;	/* Point Vgroup ID */
    int32           nlevels;	/* Number of levels in point */
    int32           vdataID;	/* Level Vdata ID */
    int32           vdataID0;	/* LevelWritten Vdata ID */
    int32           tag;	/* Vdata tag */
    int32           ref;	/* Vdata reference */
    int32           nrec;	/* Number of records in level */


    /* Check for valid point ID */
    /* ------------------------ */
    status = PTchkptid(pointID, "PTnrecs", &fid, &sdInterfaceID, &ptVgrpID);


    if (status == 0)
    {
	/* Get number of levels */
	/* -------------------- */
	nlevels = Vntagrefs(ptVgrpID);


	/* Report error if no levels (vdatas) defined */
	/* ------------------------------------------ */
	if (nlevels == 0)
	{
	    status = -1;
	    HEpush(DFE_GENAPP, "PTnrecs", __FILE__, __LINE__);
	    HEreport("No Levels Defined for point ID: %d\n", pointID);
	}
	else if (nlevels < level)
	{
	    /* Report error if level # to large */
	    /* -------------------------------- */
	    status = -1;
	    HEpush(DFE_GENAPP, "PTnrecs", __FILE__, __LINE__);
	    HEreport("Only %d levels Defined for point ID: %d\n",
		     nlevels, pointID);
	}


	if (status == 0)
	{
	    /* Get level vdata ID */
	    /* ------------------ */
	    vdataID = PTXPoint[pointID % idOffset].vdID[level];


	    /* Get number of records in level */
	    /* ------------------------------ */
	    nrec = VSelts(vdataID);


	    /* If nrec = 1 check whether actual data has been written */
	    /* ------------------------------------------------------ */
	    if (nrec == 1)
	    {
		/* Attach to "LevelWritten" vdata */
		/* ------------------------------ */
		Vgettagref(ptVgrpID, 0, &tag, &ref);
		vdataID0 = VSattach(fid, ref, "r");


		/* Read record for desired level */
		/* ----------------------------- */
		VSseek(vdataID0, level);
		VSsetfields(vdataID0, "LevelWritten");
		VSread(vdataID0, &recChk, 1, FULL_INTERLACE);


		/* If level not yet written then reset nrec to 0 */
		/* --------------------------------------------- */
		if (recChk == 0)
		{
		    nrec = 0;
		}


		/* Detach for "LevelWritten" Vdata */
		/* ------------------------------- */
		VSdetach(vdataID0);
	    }
	}
    }
    return (nrec);

}




/*----------------------------------------------------------------------------|
|  BEGIN_PROLOG                                                               |
|                                                                             |
|  FUNCTION: PTnlevels                                                        |
|                                                                             |
|  DESCRIPTION: Returns the number of levels in a point data set.             |
|                                                                             |
|                                                                             |
|  Return Value    Type     Units     Description                             |
|  ============   ======  =========   =====================================   |
|  nlevels        int32               Number of levels in point structure     |
|                                                                             |
|  INPUTS:                                                                    |
|  pointID        int32               point structure ID                      |
|                                                                             |
|                                                                             |
|  OUTPUTS:                                                                   |
|             None                                                            |
|                                                                             |
|  NOTES:                                                                     |
|                                                                             |
|                                                                             |
|   Date     Programmer   Description                                         |
|  ======   ============  =================================================   |
|  Jun 96   Joel Gales    Original Programmer                                 |
|                                                                             |
|  END_PROLOG                                                                 |
-----------------------------------------------------------------------------*/
int32
PTnlevels(int32 pointID)

{
    intn            status = 0;	/* routine return status variable */

    int32           fid;	/* HDF-EOS file id */
    int32           sdInterfaceID;	/* HDF SDS interface ID */
    int32           idOffset = PTIDOFFSET;	/* Point ID offset */
    int32           ptVgrpID;	/* Point Vgroup ID */
    int32           nlevels;	/* Number of levels in point */


    /* Check for valid point ID */
    /* ------------------------ */
    status = PTchkptid(pointID, "PTnlevels", &fid, &sdInterfaceID, &ptVgrpID);


    /* Get number of levels (Number of entries in Data Vgroup */
    /* ------------------------------------------------------ */
    if (status == 0)
    {
	nlevels = Vntagrefs(PTXPoint[pointID % idOffset].VIDTable[0]);
    }
    return (nlevels);
}





/*----------------------------------------------------------------------------|
|  BEGIN_PROLOG                                                               |
|                                                                             |
|  FUNCTION: PTsizeof                                                         |
|                                                                             |
|  DESCRIPTION: Returns size in bytes for specified fields in a point         |
|               data set.                                                     |
|                                                                             |
|                                                                             |
|  Return Value    Type     Units     Description                             |
|  ============   ======  =========   =====================================   |
|  fldsz          int32               Size in bytes of fields                 |
|                                                                             |
|  INPUTS:                                                                    |
|  pointID        int32               point structure ID                      |
|  fieldlist      char                field list (comma-separated)            |
|                                                                             |
|  OUTPUTS:                                                                   |
|  fldlevels      int32               Levels of fields                        |
|                                                                             |
|                                                                             |
|  NOTES:                                                                     |
|                                                                             |
|                                                                             |
|   Date     Programmer   Description                                         |
|  ======   ============  =================================================   |
|  Jun 96   Joel Gales    Original Programmer                                 |
|                                                                             |
|  END_PROLOG                                                                 |
-----------------------------------------------------------------------------*/
int32
PTsizeof(int32 pointID, char *fieldlist, int32 fldlevels[])
{
    intn            i;		/* Loop index */
    intn            j;		/* Loop index */
    intn            status = 0;	/* routine return status variable */

    uint8           found[VSFIELDMAX];	/* Field found flag array */

    int32           fid;	/* HDF-EOS file id */
    int32           sdInterfaceID;	/* HDF SDS interface ID */
    int32           idOffset = PTIDOFFSET;	/* Point ID offset */
    int32           ptVgrpID;	/* Point Vgroup ID */
    int32           nlevels;	/* Number of levels in point */
    int32           nflds;	/* Number of fields in fieldlist */
    int32           vdataID;	/* Vdata ID */
    int32           slen[VSFIELDMAX];	/* String length array */
    int32           fldsz = 0;	/* Record size in bytes */

    char           *pntr[VSFIELDMAX];	/* String pointer array */