[gdal-dev] point within polygon c++ API problem

[Ran, Limei]

Hello,

I am working on a C++ codes which reads polygon from polygon shapefile to see whether a point is within a polygon.  But, I got segmentation fault for pt.within (poGeometry).  Could you tell me where I may have errors.


1.      GDAL 1.9.1 is compiled with currect GEOS 3.3.6

2.      My c++ program compiled with GDAL.

3.      Here are my codes:

......
      float x = grid.x[col];
       float y = grid.y[row];

       OGRPoint pt;
        pt.setX( x );
        pt.setY( y );

        printf ("\tSet point\n");

        OGRFeature *poFeature;
        poLayer->ResetReading();

        while( (poFeature = poLayer->GetNextFeature()) != NULL )
        {
           OGRFeatureDefn *poFDefn = poLayer->GetLayerDefn();
           int iField;

           OGRGeometry *poGeometry;

           poGeometry = poFeature->GetGeometryRef();
           if( poGeometry != NULL && ( poGeometry->getGeometryType() ) == wkbPolygon )
           {
              printf ("\tGot polygon\n");

              if ( pt.Within ( poGeometry ) )
              {  //find the polygon where point is within and get item values

                 printf ("\tpoint in polygon\n");
.........

I got segmentation fault when processing gets:  if ( pt.Within ( poGeometry ) )


Thank you,

Limei

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/gdal-dev/attachments/20121218/bbb23095/attachment.html>