avc_e00parse.c

用于读取TAB、MIF、SHP文件的类

    nLen = strlen(pszLine);

    if (psInfo->numItems == 0)
    {
        /*-------------------------------------------------------------
         * Begin processing a new object, read header line:
         *    ArcId, UserId, FNode, TNode, LPoly, RPoly, numVertices
         *------------------------------------------------------------*/
        if (nLen < 70)
        {
            CPLError(CE_Failure, CPLE_AppDefined, 
                     "Error parsing E00 ARC line: \"%s\"", pszLine);
            return NULL;
        }
        else
        {
            psArc->nArcId = AVCE00Str2Int(pszLine, 10);
            psArc->nUserId = AVCE00Str2Int(pszLine+10, 10);
            psArc->nFNode = AVCE00Str2Int(pszLine+20, 10);
            psArc->nTNode = AVCE00Str2Int(pszLine+30, 10);
            psArc->nLPoly = AVCE00Str2Int(pszLine+40, 10);
            psArc->nRPoly = AVCE00Str2Int(pszLine+50, 10);
            psArc->numVertices = AVCE00Str2Int(pszLine+60, 10);
            
            /* Realloc the array of vertices 
             */
            psArc->pasVertices = (AVCVertex*)CPLRealloc(psArc->pasVertices,
                                                        psArc->numVertices*
                                                        sizeof(AVCVertex));

            /* psInfo->iCurItem is the last vertex that was read.
             * psInfo->numItems is the number of vertices to read.
             */
            psInfo->iCurItem = 0;
            psInfo->numItems = psArc->numVertices;
        }
    }
    else if (psInfo->iCurItem < psInfo->numItems && 
             psInfo->nPrecision == AVC_SINGLE_PREC &&
             ( (psInfo->iCurItem==psInfo->numItems-1 && nLen >= 28) ||
               nLen >= 56 )  )
    {
        /*-------------------------------------------------------------
         * Single precision ARCs: 2 pairs of X,Y values per line
         * Except on the last line with an odd number of vertices)
         *------------------------------------------------------------*/
        psArc->pasVertices[psInfo->iCurItem].x = atof(pszLine);
        psArc->pasVertices[psInfo->iCurItem++].y = atof(pszLine+14);
        if (psInfo->iCurItem < psInfo->numItems && nLen >= 56)
        {
            psArc->pasVertices[psInfo->iCurItem].x = atof(pszLine+28);
            psArc->pasVertices[psInfo->iCurItem++].y = atof(pszLine+42);
        }
    }
    else if (psInfo->iCurItem < psInfo->numItems && 
             psInfo->nPrecision == AVC_DOUBLE_PREC &&
             nLen >= 42)
    {
        /*-------------------------------------------------------------
         * Double precision ARCs: 1 pair of X,Y values per line
         *------------------------------------------------------------*/
        psArc->pasVertices[psInfo->iCurItem].x = atof(pszLine);
        psArc->pasVertices[psInfo->iCurItem++].y = atof(pszLine+21);
    }
    else
    {
        CPLError(CE_Failure, CPLE_AppDefined, 
                 "Error parsing E00 ARC line: \"%s\"", pszLine);
        psInfo->numItems = psInfo->iCurItem = 0;
        return NULL;
    }

    /*-----------------------------------------------------------------
     * If we're done parsing this ARC, then reset the ParseInfo,
     * and return a reference to the ARC structure
     * Otherwise return NULL, which means that we are expecting more
     * more lines of input.
     *----------------------------------------------------------------*/
    if (psInfo->iCurItem >= psInfo->numItems)
    {
        psInfo->numItems = psInfo->iCurItem = 0;
        return psArc;
    }

    return NULL;
}

/**********************************************************************
 *                          AVCE00ParseNextPalLine()
 *
 * Take the next line of E00 input for an PAL object and parse it.
 *
 * Returns NULL if the current object is not complete yet (expecting
 * more lines of input) or a reference to a complete object if it
 * is complete.
 *
 * The returned object is a reference to an internal data structure.
 * It should not be modified or freed by the caller.
 *
 * If the input is invalid or other problems happen, then a CPLError()
 * will be generated.  CPLGetLastErrorNo() should be called to check
 * that the line was parsed succesfully.
 **********************************************************************/
AVCPal   *AVCE00ParseNextPalLine(AVCE00ParseInfo *psInfo, const char *pszLine)
{
    AVCPal *psPal;
    int     nLen;

    CPLAssert(psInfo->eFileType == AVCFilePAL ||
              psInfo->eFileType == AVCFileRPL );

    psPal = psInfo->cur.psPal;

    nLen = strlen(pszLine);

    if (psInfo->numItems == 0)
    {
        /*-------------------------------------------------------------
         * Begin processing a new object, read header line:
         *    numArcs, MinX, MinY, MaxX, MaxY
         * For Double precision, MaxX, MaxY are on a separate line.
         *------------------------------------------------------------*/
        if (nLen < 52)
        {
            CPLError(CE_Failure, CPLE_AppDefined, 
                     "Error parsing E00 PAL line: \"%s\"", pszLine);
            return NULL;
        }
        else
        {
            /* Polygon Id is not stored in the E00 file.  Polygons are
             * stored in increasing order, starting at 1... so we just 
             * increment the previous value.
             */
            psPal->nPolyId = ++psInfo->nCurObjectId;

            psPal->numArcs = AVCE00Str2Int(pszLine, 10);

            /* If a PAL record has 0 arcs, it really has a single "0 0 0"
             * triplet as its data.
             */
            if ( psPal->numArcs == 0 )
            {
               psPal->numArcs = 1;
            }

            /* Realloc the array of Arcs
             */
            psPal->pasArcs = (AVCPalArc*)CPLRealloc(psPal->pasArcs,
                                                    psPal->numArcs*
                                                    sizeof(AVCPalArc));

            /* psInfo->iCurItem is the index of the last arc that was read.
             * psInfo->numItems is the number of arcs to read.
             */
            psInfo->iCurItem = 0;
            psInfo->numItems = psPal->numArcs;

            if (psInfo->nPrecision == AVC_SINGLE_PREC)
            {
                psPal->sMin.x = atof(pszLine + 10);
                psPal->sMin.y = atof(pszLine + 24);
                psPal->sMax.x = atof(pszLine + 38);
                psPal->sMax.y = atof(pszLine + 52);
            }
            else
            {
                psPal->sMin.x = atof(pszLine + 10);
                psPal->sMin.y = atof(pszLine + 31);
                /* Set psInfo->iCurItem = -1 since we still have 2 values
                 * from the header to read on the next line.
                 */
                psInfo->iCurItem = -1;
            }

        }
    }
    else if (psInfo->iCurItem == -1 && nLen >= 42)
    {
        psPal->sMax.x = atof(pszLine);
        psPal->sMax.y = atof(pszLine + 21);
        psInfo->iCurItem++;
    }
    else if (psInfo->iCurItem < psPal->numArcs && 
             (nLen >= 60 ||
              (psInfo->iCurItem == psPal->numArcs-1 && nLen >= 30)) )
    {
        /*-------------------------------------------------------------
         * 2 PAL entries (ArcId, FNode, AdjPoly) per line, 
         * (Except on the last line with an odd number of vertices)
         *------------------------------------------------------------*/
        psPal->pasArcs[psInfo->iCurItem].nArcId = AVCE00Str2Int(pszLine, 10);
        psPal->pasArcs[psInfo->iCurItem].nFNode = AVCE00Str2Int(pszLine+10,10);
        psPal->pasArcs[psInfo->iCurItem++].nAdjPoly = AVCE00Str2Int(pszLine+20,
                                                                    10);

        if (psInfo->iCurItem < psInfo->numItems)
        {
            psPal->pasArcs[psInfo->iCurItem].nArcId = AVCE00Str2Int(pszLine+30,
                                                                    10);
            psPal->pasArcs[psInfo->iCurItem].nFNode = AVCE00Str2Int(pszLine+40,
                                                                    10);
            psPal->pasArcs[psInfo->iCurItem++].nAdjPoly = 
                                                AVCE00Str2Int(pszLine+50, 10);
        }
 
    }
    else
    {
        CPLError(CE_Failure, CPLE_AppDefined, 
                 "Error parsing E00 PAL line: \"%s\"", pszLine);
        psInfo->numItems = psInfo->iCurItem = 0;
        return NULL;
    }

    /*-----------------------------------------------------------------
     * If we're done parsing this PAL, then reset the ParseInfo,
     * and return a reference to the PAL structure
     * Otherwise return NULL, which means that we are expecting more
     * more lines of input.
     *----------------------------------------------------------------*/
    if (psInfo->iCurItem >= psInfo->numItems)
    {
        psInfo->numItems = psInfo->iCurItem = 0;
        return psPal;
    }

    return NULL;
}


/**********************************************************************
 *                          AVCE00ParseNextCntLine()
 *
 * Take the next line of E00 input for an CNT object and parse it.
 *
 * Returns NULL if the current object is not complete yet (expecting
 * more lines of input) or a reference to a complete object if it
 * is complete.
 *
 * The returned object is a reference to an internal data structure.
 * It should not be modified or freed by the caller.
 *
 * If the input is invalid or other problems happen, then a CPLError()
 * will be generated.  CPLGetLastErrorNo() should be called to check
 * that the line was parsed succesfully.
 **********************************************************************/
AVCCnt   *AVCE00ParseNextCntLine(AVCE00ParseInfo *psInfo, const char *pszLine)
{
    AVCCnt *psCnt;
    int     nLen;

    CPLAssert(psInfo->eFileType == AVCFileCNT);

    psCnt = psInfo->cur.psCnt;

    nLen = strlen(pszLine);

    if (psInfo->numItems == 0)
    {
        /*-------------------------------------------------------------
         * Begin processing a new object, read header line:
         *    numLabels, X, Y
         *------------------------------------------------------------*/
        if (nLen < 38)
        {
            CPLError(CE_Failure, CPLE_AppDefined, 
                     "Error parsing E00 CNT line: \"%s\"", pszLine);
            return NULL;
        }
        else
        {
            /* Polygon Id is not stored in the E00 file.  Centroids are
             * stored in increasing order of Polygon Id, starting at 1...
             * so we just increment the previous value.
             */
            psCnt->nPolyId = ++psInfo->nCurObjectId;

            psCnt->numLabels = AVCE00Str2Int(pszLine, 10);

            /* Realloc the array of Labels Ids
             * Avoid allocating a 0-length segment since centroids can have
             * 0 labels attached to them.
             */
            if (psCnt->numLabels > 0)
                psCnt->panLabelIds = (GInt32 *)CPLRealloc(psCnt->panLabelIds,
                                                          psCnt->numLabels*
                                                          sizeof(GInt32));

            if (psInfo->nPrecision == AVC_SINGLE_PREC)
            {
                psCnt->sCoord.x = atof(pszLine + 10);
                psCnt->sCoord.y = atof(pszLine + 24);
            }
            else
            {
                psCnt->sCoord.x = atof(pszLine + 10);
                psCnt->sCoord.y = atof(pszLine + 31);
            }

            /* psInfo->iCurItem is the index of the last label that was read.
             * psInfo->numItems is the number of label ids to read.
             */
            psInfo->iCurItem = 0;
            psInfo->numItems = psCnt->numLabels;

        }
    }
    else if (psInfo->iCurItem < psInfo->numItems )
    {
        /*-------------------------------------------------------------
         * Each line can contain up to 8 label ids (10 chars each)
         *------------------------------------------------------------*/
        int i=0;
        while(psInfo->iCurItem < psInfo->numItems && nLen >= (i+1)*10)
        {
            psCnt->panLabelIds[psInfo->iCurItem++] = 
                                  AVCE00Str2Int(pszLine + i*10, 10);
            i++;
        }

    }
    else
    {
        CPLError(CE_Failure, CPLE_AppDefined, 
                 "Error parsing E00 CNT line: \"%s\"", pszLine);
        psInfo->numItems = psInfo->iCurItem = 0;
        return NULL;
    }

    /*-----------------------------------------------------------------
     * If we're done parsing this CNT, then reset the ParseInfo,
     * and return a reference to the CNT structure
     * Otherwise return NULL, which means that we are expecting more
     * more lines of input.
     *----------------------------------------------------------------*/
    if (psInfo->iCurItem >= psInfo->numItems)
    {
        psInfo->numItems = psInfo->iCurItem = 0;
        return psCnt;
    }

    return NULL;
}

/**********************************************************************