找了一个C库读取shapefile

可以读取shapefile， 但是shapefile本身不含有topology，所以仍不能满足要求。

http://shapelib.maptools.org/shp_api.html

bool

NServerData::initShapeFile(){
    const char* shp = "shapefile/freeway_polyline.shp";
    const char* shx = "shapefile/freeway_polyline.shx";
    const char* right = "rb";

    // read shp file
    SHPHandle h = SHPOpen(shp, right);
    int pnEntities;
    int pnShapeType;
    double padfMinBound;
    double padfMaxBound;
    SHPGetInfo( h, &pnEntities, &pnShapeType,
                     &padfMinBound, &padfMaxBound );
    cout << "shape info:"
            << pnEntities << " "
            << pnShapeType << " "
            << padfMinBound << " "
            << padfMaxBound << endl;
    SHPObject* obj = NULL;
    static int i=0;
    obj = SHPReadObject( h,i );
    while (obj){
        cout << ++i << " " << obj->nShapeId  << " " << obj->nVertices << endl;
        SHPDestroyObject(obj);
        obj = SHPReadObject( h, i );
    }
    SHPClose(h);

    // read shx file
    
}