[Gdal-dev] importFromWkt() problem

[Petteri Packalen]

Mateusz, Frank and others,

> Are you running your code on Windows with DLLs? If you
> are, then may be you're dealing with "passing objects
> across DLL boundaries" issue.

I rewrote this part of the code using OGR C interface and now it works 
perfectly using both approaches I presented previously. Probably it was 
some sort of dll/heap issue. I use precompiled dll from FWTools under 
Windows.

I also noticed that there was a substantial memory leak in my code. I was 
creating new OGRSpatialReference within a loop which browses through 
features:

while ( TRUE )
{
    ... // Create WKT
    OGRSpatialReferenceH hRef = OSRNewSpatialReference( NULL );  // <---
    OGRGeometryH hGeomNew;
    OGRErr err = OGR_G_CreateFromWkt( &pszWkt, hRef, &hGeomNew );
    OGR_F_SetGeometryDirectly( hDstFeature, hGeomNew );
    OGR_L_CreateFeature( hDstLayer, hDstFeature )
    OGR_F_Destroy( hDstFeature );
}

Thus I instantiated very many OGRSpatialReferences. When I instantiated 
only one OGRSpatialReference out of the loop memory leak disappeared (or 
alternatively passing directly NULL to OGR_G_CreateFromWkt as spatial 
reference). I look at the source code and tried to trace why all of 
OGRSpatialReferences are not de-allocated via ~OGRFeature() --> 
~OGRGeometry() --> OGRSpatialReference::Release() but I didn't follow 
without modifying source code (I use FWTools dll). Probably reference 
counting in OGRSpatialReference cannot handle this kind of misuse of the 
OGR?

Anyway, it was my mistake. I really appreciate your help in this list.

Best regards,
Petteri

=========================================================================
Petteri Packalén 
University of Joensuu 
Faculty of Forestry 
P.O. Box 111 
80101 Joensuu
Finland 
e-mail: packalen at cs.joensuu.fi 
=========================================================================