GM_CombineAreas

GM_Error_t32 __stdcall GM_CombineAreas
(
const GM_AreaFeature_t**    aAreaList,      // IN: List of areas to combine
uint32                      aNumAreas,      // IN: Number of areas in aAreaList
const GM_Projection_t*      aAreaProj,      // IN: Projection system the area coordinates are in (use NULL for current projection)
GM_LayerHandle_t32          aNewAreaLayer   // IN: Layer to add new combined areas to
)

// Build the list of areas to combine
GM_AreaFeature_t** theAreaList = new GM_AreaFeature_t*[ theLayerInfo->mNumAreas ];
uint32 i;
for ( i = 0; i < theLayerInfo->mNumAreas; i++ )
{
    // Get the area feature
    theAreaList[i] = GM_GetAreaFeature( aLayerHandle, i );
}

// Create a new layer and combine the areas into it
GM_LayerHandle_t32 theNewAreaLayer = GM_CreateCustomVectorLayer( "CombinedAreas", &theLayerInfo->mNativeProj );
theErr = GM_CombineAreas( (const GM_AreaFeature_t**)theAreaList, theLayerInfo->mNumAreas, &theLayerInfo->mNativeProj, theNewAreaLayer );

// Free the area features that we combined
for ( i = 0; i < theLayerInfo->mNumAreas; i++ )
{
    GM_FreeAreaFeature( theAreaList[i] );
}

// Free the area list
delete[] theAreaList;
theAreaList = NULL;