void
GeometryGraph::addPolygon(const Polygon *p)
{
	const LineString* ls;
	const LinearRing* lr;

	ls = p->getExteriorRing();
	assert(dynamic_cast<const LinearRing*>(ls));
	lr = static_cast<const LinearRing*>(ls);
	addPolygonRing(lr, Location::EXTERIOR, Location::INTERIOR);
	for (size_t i=0, n=p->getNumInteriorRing(); i<n; ++i)
	{
		// Holes are topologically labelled opposite to the shell, since
		// the interior of the polygon lies on their opposite side
		// (on the left, if the hole is oriented CW)
		ls = p->getInteriorRingN(i);
		assert(dynamic_cast<const LinearRing*>(ls));
		lr = static_cast<const LinearRing*>(ls);
		addPolygonRing(lr, Location::INTERIOR, Location::EXTERIOR);
	}
}
Ejemplo n.º 2
0
void
OffsetCurveSetBuilder::addPolygon(const Polygon *p)
{
	double offsetDistance=distance;
	int offsetSide=Position::LEFT;
	if (distance < 0.0) {
		offsetDistance=-distance;
		offsetSide=Position::RIGHT;
	}
	const LinearRing *shell=(const LinearRing *)p->getExteriorRing();
	CoordinateSequence *shellCoord = CoordinateSequence::removeRepeatedPoints(shell->getCoordinatesRO());
	// optimization - don't bother computing buffer
	// if the polygon would be completely eroded
	if (distance < 0.0 && isErodedCompletely(shellCoord, distance))
	{
		delete shellCoord;
		return;
	}
	addPolygonRing(shellCoord,offsetDistance,offsetSide,Location::EXTERIOR,Location::INTERIOR);
	delete shellCoord;
	for (int i=0;i<p->getNumInteriorRing(); i++) {
		const LinearRing *hole=(const LinearRing *)p->getInteriorRingN(i);
		CoordinateSequence *holeCoord=CoordinateSequence::removeRepeatedPoints(hole->getCoordinatesRO());

		// optimization - don't bother computing buffer for this hole
		// if the hole would be completely covered
		if (distance > 0.0 && isErodedCompletely(holeCoord, -distance))
		{
			delete holeCoord;
			continue;
		}
		// Holes are topologically labelled opposite to the shell, since
		// the interior of the polygon lies on their opposite side
		// (on the left, if the hole is oriented CCW)
		addPolygonRing(holeCoord,offsetDistance,Position::opposite(offsetSide),Location::INTERIOR,Location::EXTERIOR);
		delete holeCoord;
	}
}
/*private*/
void
OffsetCurveSetBuilder::addPolygon(const Polygon *p)
{
	double offsetDistance=distance;

	int offsetSide=Position::LEFT;
	if (distance < 0.0)
	{
		offsetDistance = -distance;
		offsetSide = Position::RIGHT;
	}

	// FIXME: avoid the C-style cast
	const LinearRing *shell=(const LinearRing *)p->getExteriorRing();
	CoordinateSequence *shellCoord = CoordinateSequence::removeRepeatedPoints(shell->getCoordinatesRO());

	// optimization - don't bother computing buffer
	// if the polygon would be completely eroded
	if (distance < 0.0 && isErodedCompletely(shellCoord, distance))
	{
		delete shellCoord;
		return;
	}

	// don't attemtp to buffer a polygon
	// with too few distinct vertices
	if (distance <= 0.0 && shellCoord->size() < 3)
	{
		delete shellCoord;
        	return;
	}

	addPolygonRing(
		shellCoord,
		offsetDistance,
		offsetSide,
		Location::EXTERIOR,
		Location::INTERIOR);

	delete shellCoord;

	for (size_t i=0, n=p->getNumInteriorRing(); i<n; ++i)
	{
		const LineString *hls=p->getInteriorRingN(i);
		assert(dynamic_cast<const LinearRing *>(hls));
		const LinearRing *hole=static_cast<const LinearRing *>(hls);
		CoordinateSequence *holeCoord=CoordinateSequence::removeRepeatedPoints(hole->getCoordinatesRO());

		// optimization - don't bother computing buffer for this hole
		// if the hole would be completely covered
		if (distance > 0.0 && isErodedCompletely(holeCoord, -distance))
		{
			delete holeCoord;
			continue;
		}

		// Holes are topologically labelled opposite to the shell,
		// since the interior of the polygon lies on their opposite
		// side (on the left, if the hole is oriented CCW)
		addPolygonRing(
			holeCoord,
			offsetDistance,
			Position::opposite(offsetSide),
			Location::INTERIOR,
			Location::EXTERIOR);

		delete holeCoord;
	}
}