bool LabelPosition::crossesBoundary( PointSet *polygon ) const
{
if ( !mGeos )
createGeosGeom();
if ( !polygon->mGeos )
polygon->createGeosGeom();
GEOSContextHandle_t geosctxt = geosContext();
try
{
if ( GEOSPreparedOverlaps_r( geosctxt, polygon->preparedGeom(), mGeos ) == 1
|| GEOSPreparedTouches_r( geosctxt, polygon->preparedGeom(), mGeos ) == 1 )
{
return true;
}
else if ( nextPart )
{
return nextPart->crossesBoundary( polygon );
}
}
catch ( GEOSException &e )
{
QgsMessageLog::logMessage( QObject::tr( "Exception: %1" ).arg( e.what() ), QObject::tr( "GEOS" ) );
return false;
}
return false;
}
bool LabelPosition::crossesLine( PointSet* line ) const
{
if ( !mGeos )
createGeosGeom();
if ( !line->mGeos )
line->createGeosGeom();
GEOSContextHandle_t geosctxt = geosContext();
try
{
if ( GEOSPreparedIntersects_r( geosctxt, line->preparedGeom(), mGeos ) == 1 )
{
return true;
}
else if ( nextPart )
{
return nextPart->crossesLine( line );
}
}
catch ( GEOSException &e )
{
QgsMessageLog::logMessage( QObject::tr( "Exception: %1" ).arg( e.what() ), QObject::tr( "GEOS" ) );
return false;
}
return false;
}
bool LabelPosition::isInConflictSinglePart( LabelPosition* lp )
{
if ( !mGeos )
createGeosGeom();
if ( !lp->mGeos )
lp->createGeosGeom();
GEOSContextHandle_t geosctxt = geosContext();
bool result = ( GEOSPreparedIntersects_r( geosctxt, preparedGeom(), lp->mGeos ) == 1 );
return result;
}
int LabelPosition::polygonIntersectionCost( PointSet *polygon ) const
{
if ( !mGeos )
createGeosGeom();
if ( !polygon->mGeos )
polygon->createGeosGeom();
GEOSContextHandle_t geosctxt = geosContext();
int cost = 0;
//check the label center. if covered by polygon, initial cost of 4
if ( polygon->containsPoint(( x[0] + x[2] ) / 2.0, ( y[0] + y[2] ) / 2.0 ) )
cost += 4;
try
{
//calculate proportion of label candidate which is covered by polygon
GEOSGeometry* intersectionGeom = GEOSIntersection_r( geosctxt, mGeos, polygon->mGeos );
if ( !intersectionGeom )
return cost;
double positionArea = 0;
if ( GEOSArea_r( geosctxt, mGeos, &positionArea ) != 1 )
{
GEOSGeom_destroy_r( geosctxt, intersectionGeom );
return cost;
}
double intersectionArea = 0;
if ( GEOSArea_r( geosctxt, intersectionGeom, &intersectionArea ) != 1 )
{
intersectionArea = 0;
}
GEOSGeom_destroy_r( geosctxt, intersectionGeom );
double portionCovered = intersectionArea / positionArea;
cost += ceil( portionCovered * 8.0 ); //cost of 8 if totally covered
return cost;
}
catch ( GEOSException &e )
{
QgsMessageLog::logMessage( QObject::tr( "Exception: %1" ).arg( e.what() ), QObject::tr( "GEOS" ) );
return cost;
}
}
bool LabelPosition::isInConflictSinglePart( LabelPosition* lp )
{
if ( !mGeos )
createGeosGeom();
if ( !lp->mGeos )
lp->createGeosGeom();
GEOSContextHandle_t geosctxt = geosContext();
try
{
bool result = ( GEOSPreparedIntersects_r( geosctxt, preparedGeom(), lp->mGeos ) == 1 );
return result;
}
catch ( GEOSException &e )
{
QgsMessageLog::logMessage( QObject::tr( "Exception: %1" ).arg( e.what() ), QObject::tr( "GEOS" ) );
return false;
}
}
bool LabelPosition::crossesLine( PointSet* line ) const
{
if ( !mGeos )
createGeosGeom();
if ( !line->mGeos )
line->createGeosGeom();
GEOSContextHandle_t geosctxt = geosContext();
if ( GEOSPreparedIntersects_r( geosctxt, line->preparedGeom(), mGeos ) == 1 )
{
return true;
}
else if ( nextPart )
{
return nextPart->crossesLine( line );
}
return false;
}
bool LabelPosition::crossesBoundary( PointSet *polygon ) const
{
if ( !mGeos )
createGeosGeom();
if ( !polygon->mGeos )
polygon->createGeosGeom();
GEOSContextHandle_t geosctxt = geosContext();
if ( GEOSPreparedOverlaps_r( geosctxt, polygon->preparedGeom(), mGeos ) == 1
|| GEOSPreparedTouches_r( geosctxt, polygon->preparedGeom(), mGeos ) == 1 )
{
return true;
}
else if ( nextPart )
{
return nextPart->crossesBoundary( polygon );
}
return false;
}