bool
Geometry::difference( const Polygon* diffPolygon, osg::ref_ptr<Geometry>& output ) const
{
#ifdef OSGEARTH_HAVE_GEOS
GEOSContext gc;
//Create the GEOS Geometries
geom::Geometry* inGeom = gc.importGeometry( this );
geom::Geometry* diffGeom = gc.importGeometry( diffPolygon );
if ( inGeom )
{
geom::Geometry* outGeom = 0L;
try {
outGeom = overlay::OverlayOp::overlayOp(
inGeom,
diffGeom,
overlay::OverlayOp::opDIFFERENCE );
}
catch(const geos::util::GEOSException& ex) {
OE_NOTICE << LC << "Diff(GEOS): "
<< (ex.what()? ex.what() : " no error message")
<< std::endl;
outGeom = 0L;
}
if ( outGeom )
{
output = gc.exportGeometry( outGeom );
gc.disposeGeometry( outGeom );
if ( output.valid() && !output->isValid() )
{
output = 0L;
}
}
}
//Destroy the geometry
gc.disposeGeometry( diffGeom );
gc.disposeGeometry( inGeom );
return output.valid();
#else // OSGEARTH_HAVE_GEOS
OE_WARN << LC << "Difference failed - GEOS not available" << std::endl;
return false;
#endif // OSGEARTH_HAVE_GEOS
}
bool
Geometry::geounion( const Geometry* other, osg::ref_ptr<Geometry>& output ) const
{
#ifdef OSGEARTH_HAVE_GEOS
bool success = false;
output = 0L;
GEOSContext gc;
//Create the GEOS Geometries
geom::Geometry* inGeom = gc.importGeometry( this );
geom::Geometry* otherGeom = gc.importGeometry( other );
if ( inGeom )
{
geom::Geometry* outGeom = 0L;
try {
outGeom = overlay::OverlayOp::overlayOp(
inGeom,
otherGeom,
overlay::OverlayOp::opUNION );
}
catch(const geos::util::GEOSException& ex) {
OE_NOTICE << LC << "Union(GEOS): "
<< (ex.what()? ex.what() : " no error message")
<< std::endl;
outGeom = 0L;
}
if ( outGeom )
{
output = gc.exportGeometry( outGeom );
if ( output.valid())
{
if ( output->isValid() )
{
success = true;
}
else
{
// GEOS result is invalid
output = 0L;
}
}
else
{
// set output to empty geometry to indicate the (valid) empty case,
// still returning false but allows for check.
if (outGeom->getNumPoints() == 0)
{
output = new osgEarth::Symbology::Geometry();
}
}
gc.disposeGeometry( outGeom );
}
}
//Destroy the geometry
gc.disposeGeometry( otherGeom );
gc.disposeGeometry( inGeom );
return success;
#else // OSGEARTH_HAVE_GEOS
OE_WARN << LC << "Union failed - GEOS not available" << std::endl;
return false;
#endif // OSGEARTH_HAVE_GEOS
}
bool
Geometry::buffer(double distance,
osg::ref_ptr<Geometry>& output,
const BufferParameters& params ) const
{
#ifdef OSGEARTH_HAVE_GEOS
GEOSContext gc;
geom::Geometry* inGeom = gc.importGeometry( this );
if ( inGeom )
{
buffer::BufferParameters::EndCapStyle geosEndCap =
params._capStyle == BufferParameters::CAP_ROUND ? buffer::BufferParameters::CAP_ROUND :
params._capStyle == BufferParameters::CAP_SQUARE ? buffer::BufferParameters::CAP_SQUARE :
params._capStyle == BufferParameters::CAP_FLAT ? buffer::BufferParameters::CAP_FLAT :
buffer::BufferParameters::CAP_SQUARE;
buffer::BufferParameters::JoinStyle geosJoinStyle =
params._joinStyle == BufferParameters::JOIN_ROUND ? buffer::BufferParameters::JOIN_ROUND :
params._joinStyle == BufferParameters::JOIN_MITRE ? buffer::BufferParameters::JOIN_MITRE :
params._joinStyle == BufferParameters::JOIN_BEVEL ? buffer::BufferParameters::JOIN_BEVEL :
buffer::BufferParameters::JOIN_ROUND;
//JB: Referencing buffer::BufferParameters::DEFAULT_QUADRANT_SEGMENTS causes link errors b/c it is defined as a static in the header of BufferParameters.h and not defined in the cpp anywhere.
// This seems to only effect the Linux build, Windows works fine
int geosQuadSegs = params._cornerSegs > 0
? params._cornerSegs
: 8; //buffer::BufferParameters::DEFAULT_QUADRANT_SEGMENTS;
geom::Geometry* outGeom = NULL;
buffer::BufferParameters geosBufferParams;
geosBufferParams.setQuadrantSegments( geosQuadSegs );
geosBufferParams.setEndCapStyle( geosEndCap );
geosBufferParams.setJoinStyle( geosJoinStyle );
buffer::BufferBuilder bufBuilder( geosBufferParams );
try
{
if (params._singleSided)
{
outGeom = bufBuilder.bufferLineSingleSided(inGeom, distance, params._leftSide);
}
else
{
outGeom = bufBuilder.buffer(inGeom, distance);
}
}
catch(const geos::util::GEOSException& ex)
{
OE_NOTICE << LC << "buffer(GEOS): "
<< (ex.what()? ex.what() : " no error message")
<< std::endl;
outGeom = 0L;
}
bool sharedFactory =
inGeom && outGeom &&
inGeom->getFactory() == outGeom->getFactory();
if ( outGeom )
{
output = gc.exportGeometry( outGeom );
gc.disposeGeometry( outGeom );
}
gc.disposeGeometry( inGeom );
}
return output.valid();
#else // OSGEARTH_HAVE_GEOS
OE_WARN << LC << "Buffer failed - GEOS not available" << std::endl;
return false;
#endif // OSGEARTH_HAVE_GEOS
}
