gdapi.c

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

		/*
		 * If Vgroup with gridname and class GRID found, load tables
		 */

		if (strcmp(name, gridname) == 0 &&
		    strcmp(class, "GRID") == 0)
		{
		    /* Attach to "Data Fields" and "Grid Attributes" Vgroups */
		    /* ----------------------------------------------------- */
		    tags = (int32 *) malloc(sizeof(int32) * 2);
		    if(tags == NULL)
		    { 
			HEpush(DFE_NOSPACE,"GDattach", __FILE__, __LINE__);
			return(-1);
		    }
		    refs = (int32 *) malloc(sizeof(int32) * 2);
		    if(refs == NULL)
		    { 
			HEpush(DFE_NOSPACE,"GDattach", __FILE__, __LINE__);
			free(tags);
			return(-1);
		    }
		    Vgettagrefs(vgid[0], tags, refs, 2);
		    vgid[1] = Vattach(HDFfid, refs[0], acsCode);
		    vgid[2] = Vattach(HDFfid, refs[1], acsCode);
		    free(tags);
		    free(refs);


		    /* Setup External Arrays */
		    /* --------------------- */
		    for (i = 0; i < NGRID; i++)
		    {
			/* Find empty entry in array */
			/* ------------------------- */
			if (GDXGrid[i].active == 0)
			{
			    /*
			     * Set gridID, Set grid entry active, Store root
			     * Vgroup ID, Store sub Vgroup IDs, Store HDF-EOS
			     * file ID
			     */
			    gridID = i + idOffset;
			    GDXGrid[i].active = 1;
			    GDXGrid[i].IDTable = vgid[0];
			    GDXGrid[i].VIDTable[0] = vgid[1];
			    GDXGrid[i].VIDTable[1] = vgid[2];
			    GDXGrid[i].fid = fid;
			    break;
			}
		    }

		    /* Get SDS interface ID */
		    /* -------------------- */
		    status = GDchkgdid(gridID, "GDattach", &dum,
				       &sdInterfaceID, &dum);


		    /* Get # of entries within Data Vgroup & search for SDS */
		    /* ---------------------------------------------------- */
		    nObjects = Vntagrefs(vgid[1]);

		    if (nObjects > 0)
		    {
			/* Get tag and ref # for Data Vgroup objects */
			/* ----------------------------------------- */
			tags = (int32 *) malloc(sizeof(int32) * nObjects);
			if(tags == NULL)
			{ 
			    HEpush(DFE_NOSPACE,"GDattach", __FILE__, __LINE__);
			    return(-1);
			}
			refs = (int32 *) malloc(sizeof(int32) * nObjects);
			if(refs == NULL)
			{ 
			    HEpush(DFE_NOSPACE,"GDattach", __FILE__, __LINE__);
			    free(tags);
			    return(-1);
			}
			Vgettagrefs(vgid[1], tags, refs, nObjects);

			/* Count number of SDS & allocate SDS ID array */
			/* ------------------------------------------- */
			nSDS = 0;
			for (j = 0; j < nObjects; j++)
			{
			    if (tags[j] == DFTAG_NDG)
			    {
				nSDS++;
			    }
			}
			GDXGrid[i].sdsID = (int32 *) calloc(nSDS, 4);
			if(GDXGrid[i].sdsID == NULL && nSDS != 0)
			{ 
			    HEpush(DFE_NOSPACE,"GDattach", __FILE__, __LINE__);
			    free(tags);
			    free(refs);
			    return(-1);
			}
			nSDS = 0;



			/* Fill SDS ID array */
			/* ----------------- */
			for (j = 0; j < nObjects; j++)
			{
			    /* If object is SDS then get id */
			    /* ---------------------------- */
			    if (tags[j] == DFTAG_NDG)
			    {
				index = SDreftoindex(sdInterfaceID, refs[j]);
				sdid = SDselect(sdInterfaceID, index);
				GDXGrid[i].sdsID[nSDS] = sdid;
				nSDS++;
				GDXGrid[i].nSDS++;
			    }
			}
			free(tags);
			free(refs);
		    }
		    break;
		}

		/* Detach Vgroup if not desired Grid */
		/* --------------------------------- */
		Vdetach(vgid[0]);
	    }

	    /* If Grid not found then set up error message */
	    /* ------------------------------------------- */
	    if (gridID == -1)
	    {
		HEpush(DFE_RANGE, "GDattach", __FILE__, __LINE__);
		HEreport("Grid: \"%s\" does not exist within HDF file.\n",
			 gridname);
	    }
	}
	else
	{
	    /* Too many files opened */
	    /* --------------------- */
	    gridID = -1;
	    strcpy(errbuf,
		   "No more than %d grids may be open simutaneously");
	    strcat(errbuf, " (%s)");
	    HEpush(DFE_DENIED, "GDattach", __FILE__, __LINE__);
	    HEreport(errbuf, NGRID, gridname);
	}

    }
    return (gridID);
}


/*----------------------------------------------------------------------------|
|  BEGIN_PROLOG                                                               |
|                                                                             |
|  FUNCTION: GDchkgdid                                                        |
|                                                                             |
|  DESCRIPTION:                                                               |
|                                                                             |
|                                                                             |
|  Return Value    Type     Units     Description                             |
|  ============   ======  =========   =====================================   |
|  status         intn                return status (0) SUCCEED, (-1) FAIL    |
|                                                                             |
|  INPUTS:                                                                    |
|  gridID         int32               grid structure ID                       |
|  routname       char                Name of routine calling GDchkgdid       |
|                                                                             |
|  OUTPUTS:                                                                   |
|  fid            int32               File ID                                 |
|  sdInterfaceID  int32               SDS interface ID                        |
|  gdVgrpID       int32               grid Vgroup ID                          |
|                                                                             |
|                                                                             |
|  OUTPUTS:                                                                   |
|             None                                                            |
|                                                                             |
|  NOTES:                                                                     |
|                                                                             |
|                                                                             |
|   Date     Programmer   Description                                         |
|  ======   ============  =================================================   |
|  Jun 96   Joel Gales    Original Programmer                                 |
|                                                                             |
|  END_PROLOG                                                                 |
-----------------------------------------------------------------------------*/
intn
GDchkgdid(int32 gridID, char *routname,
	  int32 * fid, int32 * sdInterfaceID, int32 * gdVgrpID)
{
    intn            status = 0;	/* routine return status variable */
    uint8           access;	/* Read/Write access code */
    int32           gID;	/* Grid ID - offset */

    int32           idOffset = GDIDOFFSET;	/* Grid ID offset */

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



    /* Check for valid grid id */

    if (gridID < idOffset || gridID >= NGRID + idOffset)
    {
	status = -1;
	HEpush(DFE_RANGE, "GDchkgdid", __FILE__, __LINE__);
	HEreport(message1, gridID, routname, idOffset, NGRID + idOffset);
    }
    else
    {

	/* Compute "reduced" ID */
	/* -------------------- */
	gID = gridID % idOffset;


	/* Check for active grid ID */
	/* ------------------------ */
	if (GDXGrid[gID].active == 0)
	{
	    status = -1;
	    HEpush(DFE_GENAPP, "GDchkgdid", __FILE__, __LINE__);
	    HEreport(message2, gridID, routname);
	}
	else
	{

	    /* Get file & SDS ids and Grid key */
	    /* -------------------------------- */
	    status = EHchkfid(GDXGrid[gID].fid, " ",
			      fid, sdInterfaceID, &access);
	    *gdVgrpID = GDXGrid[gID].IDTable;
	}
    }
    return (status);

}




















/*----------------------------------------------------------------------------|
|  BEGIN_PROLOG                                                               |
|                                                                             |
|  FUNCTION: GDdefdim                                                         |
|                                                                             |
|  DESCRIPTION: Defines a new dimension within the grid.                      |
|                                                                             |
|                                                                             |
|  Return Value    Type     Units     Description                             |
|  ============   ======  =========   =====================================   |
|  status         intn                return status (0) SUCCEED, (-1) FAIL    |
|                                                                             |
|  INPUTS:                                                                    |
|  gridID         int32               grid structure ID                       |
|  dimname        char                Dimension name to define                |
|  dim            int32               Dimemsion value                         |
|                                                                             |
|                                                                             |
|  OUTPUTS:                                                                   |
|             None                                                            |
|                                                                             |
|  NOTES:                                                                     |
|                                                                             |
|                                                                             |
|   Date     Programmer   Description                                         |
|  ======   ============  =================================================   |
|  Jun 96   Joel Gales    Original Programmer                                 |
|                                                                             |
|  END_PROLOG                                                                 |
-----------------------------------------------------------------------------*/
intn
GDdefdim(int32 gridID, char *dimname, int32 dim)

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

    int32           fid;	/* HDF-EOS file id */
    int32           sdInterfaceID;	/* HDF SDS interface ID */
    int32           gdVgrpID;	/* Grid root Vgroup ID */
    int32           idOffset = GDIDOFFSET;	/* Grid ID offset */

    char            gridname[80] /* Grid name */ ;


    /* Check for valid grid id */
    status = GDchkgdid(gridID, "GDdefinedim",
		       &fid, &sdInterfaceID, &gdVgrpID);


    /* Make sure dimension >= 0 */
    /* ------------------------ */
    if (dim < 0)
    {
	status = -1;
	HEpush(DFE_GENAPP, "GDdefdim", __FILE__, __LINE__);
	HEreport("Dimension value for \"%s\" less than zero: %d.\n",
		 dimname, dim);
    }


    /* Write Dimension to Structural MetaData */