DYT/Tool/OpenSceneGraph-3.6.5/include/geos/coverage/CoveragePolygonValidator.h
2024-12-25 07:49:36 +08:00

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/**********************************************************************
*
* GEOS - Geometry Engine Open Source
* http://geos.osgeo.org
*
* Copyright (C) 2022 Paul Ramsey <pramsey@cleverelephant.ca>
*
* This is free software; you can redistribute and/or modify it under
* the terms of the GNU Lesser General Public Licence as published
* by the Free Software Foundation.
* See the COPYING file for more information.
*
**********************************************************************/
#pragma once
#include <geos/noding/BasicSegmentString.h>
#include <geos/geom/LineSegment.h>
#include <geos/algorithm/locate/IndexedPointInAreaLocator.h>
#include <geos/coverage/CoveragePolygon.h>
#include <geos/coverage/CoverageRing.h>
#include <unordered_map>
#include <map>
// Forward declarations
namespace geos {
namespace geom {
class Coordinate;
class Envelope;
class Geometry;
class GeometryFactory;
}
}
using geos::geom::Coordinate;
using geos::geom::Envelope;
using geos::geom::Geometry;
using geos::geom::GeometryFactory;
using geos::geom::LineSegment;
using geos::algorithm::locate::IndexedPointInAreaLocator;
namespace geos { // geos
namespace coverage { // geos::coverage
/**
* Validates that a polygon forms a valid polygonal coverage
* with the set of polygons adjacent to it.
* If the polygon is coverage-valid an empty {@link geos::geom::LineString} is returned.
* Otherwise, the result is a linear geometry containing
* the polygon boundary linework causing the invalidity.
*
* A polygon is coverage-valid if:
*
* * The polygon interior does not intersect the interior of other polygons.
* * If the polygon boundary intersects another polygon boundary, the vertices
* and line segments of the intersection match exactly.
*
* The algorithm detects the following coverage errors:
*
* * the polygon is a duplicate of another one
* * a polygon boundary segment equals an adjacent segment (with same orientation).
* This determines that the polygons overlap
* * a polygon boundary segment is collinear and overlaps an adjacent segment
* but is not equal to it
* * a polygon boundary segment touches an adjacent segment at a non-vertex point
* * a polygon boundary segment crosses into an adjacent polygon
* * a polygon boundary segment is in the interior of an adjacent polygon
*
* If any of these errors is present, the target polygon
* does not form a valid coverage with the adjacent polygons.
*
* The validity rules do not preclude gaps between coverage polygons.
* However, this class can detect narrow gaps,
* by specifying a maximum gap width using {@link #setGapWidth(double)}.
* Note that this will also identify narrow gaps separating disjoint coverage regions,
* and narrow gores.
* In some situations it may also produce false positives
* (i.e. linework identified as part of a gap which is wider than the given width).
* To fully identify gaps it maybe necessary to use {@link CoverageUnion} and analyze
* the holes in the result to see if they are acceptable.
*
* A polygon may be coverage-valid with respect to
* a set of surrounding polygons, but the collection as a whole may not
* form a clean coverage. For example, the target polygon boundary may be fully matched
* by adjacent boundary segments, but the adjacent set contains polygons
* which are not coverage-valid relative to other ones in the set.
* A coverage is valid only if every polygon in the coverage is coverage-valid.
* Use {@link CoverageValidator} to validate an entire set of polygons.
*
* The adjacent set may contain polygons which do not intersect the target polygon.
* These are effectively ignored during validation (but may decrease performance).
*
* @author Martin Davis
*
*/
class GEOS_DLL CoveragePolygonValidator {
private:
/**
* Models a segment in a CoverageRing.
* The segment is normalized so it can be compared with segments
* in any orientation.
* Records valid matching segments in a coverage,
* which must have opposite orientations.
* Also detects equal segments with identical
* orientation, and marks them as coverage-invalid.
*/
class CoverageRingSegment : public LineSegment
{
public:
// Members
CoverageRing* ringForward;
std::size_t indexForward;
CoverageRing* ringOpp;
std::size_t indexOpp;
CoverageRingSegment(
const Coordinate& p_p0, const Coordinate& p_p1,
CoverageRing* p_ring, std::size_t p_index)
: LineSegment(p_p0, p_p1)
, ringForward(nullptr)
, indexForward(0)
, ringOpp(nullptr)
, indexOpp(0)
{
if (p_p1.compareTo(p_p0) < 0) {
reverse();
ringOpp = p_ring;
indexOpp = p_index;
}
else {
ringForward = p_ring;
indexForward = p_index;
}
};
void match(const CoverageRingSegment* seg) {
bool isInvalid = checkInvalid(seg);
if (isInvalid) {
return;
}
//-- record the match
if (ringForward == nullptr) {
ringForward = seg->ringForward;
indexForward = seg->indexForward;
}
else {
ringOpp = seg->ringOpp;
indexOpp = seg->indexOpp;
}
//-- mark ring segments as matched
ringForward->markMatched(indexForward);
ringOpp->markMatched(indexOpp);
}
bool checkInvalid(const CoverageRingSegment* seg) const {
if (ringForward != nullptr && seg->ringForward != nullptr) {
ringForward->markInvalid(indexForward);
seg->ringForward->markInvalid(seg->indexForward);
return true;
}
if (ringOpp != nullptr && seg->ringOpp != nullptr) {
ringOpp->markInvalid(indexOpp);
seg->ringOpp->markInvalid(seg->indexOpp);
return true;
}
return false;
}
struct CoverageRingSegHash {
std::size_t
operator() (CoverageRingSegment const* s) const {
std::size_t h = std::hash<double>{}(s->p0.x);
h ^= (std::hash<double>{}(s->p0.y) << 1);
h ^= (std::hash<double>{}(s->p1.x) << 1);
return h ^ (std::hash<double>{}(s->p1.y) << 1);
}
};
struct CoverageRingSegEq {
bool
operator() (CoverageRingSegment const* lhs, CoverageRingSegment const* rhs) const {
return lhs->p0.x == rhs->p0.x
&& lhs->p0.y == rhs->p0.y
&& lhs->p1.x == rhs->p1.x
&& lhs->p1.y == rhs->p1.y;
}
};
};
// Members
const Geometry* targetGeom;
std::vector<const Geometry*> adjGeoms;
//std::vector<const Polygon*> m_adjPolygons;
const GeometryFactory* geomFactory;
double gapWidth = 0.0;
std::vector<std::unique_ptr<CoveragePolygon>> m_adjCovPolygons;
std::deque<CoverageRing> coverageRingStore;
std::vector<std::unique_ptr<CoordinateSequence>> localCoordinateSequences;
std::deque<CoverageRingSegment> coverageRingSegmentStore;
typedef std::unordered_map<CoverageRingSegment*, CoverageRingSegment*, CoverageRingSegment::CoverageRingSegHash, CoverageRingSegment::CoverageRingSegEq> CoverageRingSegmentMap;
// Declare type as noncopyable
CoveragePolygonValidator(const CoveragePolygonValidator& other) = delete;
CoveragePolygonValidator& operator=(const CoveragePolygonValidator& rhs) = delete;
public:
/**
* Validates that a polygon is coverage-valid against the
* surrounding polygons in a polygonal coverage.
*
* @param targetPolygon the polygon to validate
* @param adjPolygons the adjacent polygons
* @return a linear geometry containing the segments causing invalidity (if any)
*/
static std::unique_ptr<Geometry> validate(
const Geometry* targetPolygon,
std::vector<const Geometry*>& adjPolygons);
/**
* Validates that a polygon is coverage-valid against the
* surrounding polygons in a polygonal coverage,
* and forms no gaps narrower than a specified width.
* <p>
* The set of surrounding polygons should include all polygons which
* are within the gap width distance of the target polygon.
*
* @param targetPolygon the polygon to validate
* @param adjPolygons a collection of the adjacent polygons
* @param gapWidth the maximum width of invalid gaps
* @return a linear geometry containing the segments causing invalidity (if any)
*/
static std::unique_ptr<Geometry> validate(
const Geometry* targetPolygon,
std::vector<const Geometry*>& adjPolygons,
double gapWidth);
/**
* Create a new validator.
*
* If the gap width is specified, the set of surrounding polygons
* should include all polygons which
* are within the gap width distance of the target polygon.
*
* @param targetPolygon the geometry to validate
* @param adjPolygons the adjacent polygons in the polygonal coverage
*/
CoveragePolygonValidator(
const Geometry* targetPolygon,
std::vector<const Geometry*>& adjPolygons);
/**
* Sets the maximum gap width, if narrow gaps are to be detected.
*
* @param p_gapWidth the maximum width of gaps to detect
*/
void setGapWidth(double p_gapWidth);
/**
* Validates the coverage polygon against the set of adjacent polygons
* in the coverage.
*
* @return a linear geometry containing the segments causing invalidity (if any)
*/
std::unique_ptr<Geometry> validate();
private:
static std::vector<std::unique_ptr<CoveragePolygon>>
toCoveragePolygons(const std::vector<const Polygon*> polygons);
static std::vector<const Polygon*> extractPolygons(std::vector<const Geometry*>& geoms);
/* private */
std::unique_ptr<Geometry> createEmptyResult();
/**
* Marks matched segments.
* This improves the efficiency of validity testing, since in valid coverages
* all segments (except exterior ones) are matched,
* and hence do not need to be tested further.
* Segments which are equal and have same orientation
* are detected and marked invalid.
* In fact, the entire target polygon may be matched and valid,
* which allows avoiding further tests.
* Segments matched between adjacent polygons are also marked valid,
* since this prevents them from being detected as misaligned,
* if this is being done.
*
* @param targetRings the target rings
* @param adjRings the adjacent rings
* @param targetEnv the tolerance envelope of the target
*/
void markMatchedSegments(
std::vector<CoverageRing*>& targetRings,
std::vector<CoverageRing*>& adjRings,
const Envelope& targetEnv);
/**
* Adds ring segments to the segment map,
* and detects if they match an existing segment.
* Matched segments are marked.
*
* @param rings
* @param envLimit
* @param segmentMap
*/
void markMatchedSegments(
std::vector<CoverageRing*>& rings,
const Envelope& envLimit,
CoverageRingSegmentMap& segmentMap);
CoverageRingSegment* createCoverageRingSegment(
CoverageRing* ring, std::size_t index);
/**
* Marks invalid target segments which cross an adjacent ring segment,
* lie partially in the interior of an adjacent ring,
* or are nearly collinear with an adjacent ring segment up to the distance tolerance
*
* @param targetRings the rings with segments to test
* @param adjRings the adjacent rings
* @param distanceTolerance the gap distance tolerance, if any
*/
void markInvalidInteractingSegments(
std::vector<CoverageRing*>& targetRings,
std::vector<CoverageRing*>& adjRings,
double distanceTolerance);
/**
* Marks invalid target segments which are fully interior
* to an adjacent polygon.
*
* @param targetRings the rings with segments to test
* @param adjCovPolygons the adjacent polygons
*/
void markInvalidInteriorSegments(
std::vector<CoverageRing*>& targetRings,
std::vector<std::unique_ptr<CoveragePolygon>>& adjCovPolygons);
void markInvalidInteriorSection(
CoverageRing& ring,
std::size_t iStart,
std::size_t iEnd,
std::vector<std::unique_ptr<CoveragePolygon>>& adjCovPolygons );
void markInvalidInteriorSegment(
CoverageRing& ring, std::size_t i, CoveragePolygon* adjPoly);
void checkTargetRings(
std::vector<CoverageRing*>& targetRings,
std::vector<CoverageRing*>& adjRngs,
const Envelope& targetEnv);
std::unique_ptr<Geometry> createInvalidLines(std::vector<CoverageRing*>& rings);
std::vector<CoverageRing*> createRings(const Geometry* geom);
std::vector<CoverageRing*> createRings(std::vector<const Polygon*>& polygons);
void createRings(const Polygon* poly, std::vector<CoverageRing*>& rings);
void addRing(
const LinearRing* ring,
bool isShell,
std::vector<CoverageRing*>& rings);
CoverageRing* createRing(const LinearRing* ring, bool isShell);
};
} // namespace geos::coverage
} // namespace geos