/// <summary> /// This method is called by clients /// of the <see cref="ISegmentIntersector" /> class to process /// intersections for two segments of the <see cref="SegmentString" />s being intersected. /// Notice that some clients (such as <see cref="MonotoneChain" />s) may optimize away /// this call for segment pairs which they have determined do not intersect /// (e.g. by an disjoint envelope test). /// </summary> /// <param name="e0"></param> /// <param name="segIndex0"></param> /// <param name="e1"></param> /// <param name="segIndex1"></param> public void ProcessIntersections(SegmentString e0, int segIndex0, SegmentString e1, int segIndex1 ) { // don't bother intersecting a segment with itself if (e0 == e1 && segIndex0 == segIndex1) return; Coordinate p00 = e0.Coordinates[segIndex0]; Coordinate p01 = e0.Coordinates[segIndex0 + 1]; Coordinate p10 = e1.Coordinates[segIndex1]; Coordinate p11 = e1.Coordinates[segIndex1 + 1]; _li.ComputeIntersection(p00, p01, p10, p11); if (_li.HasIntersection) { if (_li.IsInteriorIntersection()) { for(int intIndex = 0; intIndex < _li.IntersectionNum; intIndex++) _interiorIntersections.Add(_li.GetIntersection(intIndex)); e0.AddIntersections(_li, segIndex0); e1.AddIntersections(_li, segIndex1); } } }
/// <summary> /// Initializes a new instance of the <see cref="SegmentNode"/> class. /// </summary> /// <param name="segString"></param> /// <param name="coord"></param> /// <param name="segmentIndex"></param> /// <param name="segmentOctant"></param> public SegmentNode(SegmentString segString, Coordinate coord, int segmentIndex, Octants segmentOctant) { this.segString = segString; this.Coordinate = new Coordinate(coord); this.SegmentIndex = segmentIndex; this.segmentOctant = segmentOctant; isInterior = !coord.Equals2D(segString.GetCoordinate(segmentIndex)); }
/// <summary> /// Creates a {SegmentString} for a coordinate list which is a raw offset curve, /// and adds it to the list of buffer curves. /// The SegmentString is tagged with a Label giving the topology of the curve. /// The curve may be oriented in either direction. /// If the curve is oriented CW, the locations will be: /// Left: Location.Exterior. /// Right: Location.Interior. /// </summary> private void AddCurve(IList<Coordinate> coord, Locations leftLoc, Locations rightLoc) { // don't add null curves! if (coord.Count < 2) return; // add the edge for a coordinate list which is a raw offset curve SegmentString e = new SegmentString(coord, new Label(0, Locations.Boundary, leftLoc, rightLoc)); _curveList.Add(e); }
/// <summary> /// This method is called by clients /// of the <see cref="ISegmentIntersector" /> class to process /// intersections for two segments of the <see cref="SegmentString" /> being intersected. /// Notice that some clients (such as <see cref="MonotoneChain" />s) may optimize away /// this call for segment pairs which they have determined do not intersect /// (e.g. by an disjoint envelope test). /// </summary> /// <param name="e0"></param> /// <param name="segIndex0"></param> /// <param name="e1"></param> /// <param name="segIndex1"></param> public void ProcessIntersections(SegmentString e0, int segIndex0, SegmentString e1, int segIndex1) { if (e0 == e1 && segIndex0 == segIndex1) return; _numTests++; Coordinate p00 = e0.Coordinates[segIndex0]; Coordinate p01 = e0.Coordinates[segIndex0 + 1]; Coordinate p10 = e1.Coordinates[segIndex1]; Coordinate p11 = e1.Coordinates[segIndex1 + 1]; _li.ComputeIntersection(p00, p01, p10, p11); if (!_li.HasIntersection) return; _numIntersections++; if (_li.IsInteriorIntersection()) { NumInteriorIntersections++; _hasInterior = true; } // if the segments are adjacent they have at least one trivial intersection, // the shared endpoint. Don't bother adding it if it is the // only intersection. if (IsTrivialIntersection(e0, segIndex0, e1, segIndex1)) return; _hasIntersection = true; e0.AddIntersections(_li, segIndex0); e1.AddIntersections(_li, segIndex1); if (!_li.IsProper) return; _numProperIntersections++; _hasProper = true; _hasProperInterior = true; }
/// <summary> /// A trivial intersection is an apparent self-intersection which in fact /// is simply the point shared by adjacent line segments. /// Notice that closed edges require a special check for the point shared by the beginning and end segments. /// </summary> /// <param name="e0"></param> /// <param name="segIndex0"></param> /// <param name="e1"></param> /// <param name="segIndex1"></param> /// <returns></returns> private bool IsTrivialIntersection(SegmentString e0, int segIndex0, SegmentString e1, int segIndex1) { if(e0 == e1) { if(_li.IntersectionNum == 1) { if(IsAdjacentSegments(segIndex0, segIndex1)) return true; if (e0.IsClosed) { int maxSegIndex = e0.Count - 1; if ( (segIndex0 == 0 && segIndex1 == maxSegIndex) || (segIndex1 == 0 && segIndex0 == maxSegIndex) ) return true; } } } return false; }
/// <summary> /// /// </summary> /// <param name="ss"></param> private static void CheckCollapses(SegmentString ss) { IList<Coordinate> pts = ss.Coordinates; for (int i = 0; i < pts.Count - 2; i++) CheckCollapse(pts[i], pts[i + 1], pts[i + 2]); }
/// <summary> /// /// </summary> /// <param name="e0"></param> /// <param name="segIndex0"></param> /// <param name="e1"></param> /// <param name="segIndex1"></param> private void CheckInteriorIntersections(SegmentString e0, int segIndex0, SegmentString e1, int segIndex1) { if (e0 == e1 && segIndex0 == segIndex1) return; Coordinate p00 = e0.Coordinates[segIndex0]; Coordinate p01 = e0.Coordinates[segIndex0 + 1]; Coordinate p10 = e1.Coordinates[segIndex1]; Coordinate p11 = e1.Coordinates[segIndex1 + 1]; _li.ComputeIntersection(p00, p01, p10, p11); if (_li.HasIntersection) if (_li.IsProper || HasInteriorIntersection(_li, p00, p01) || HasInteriorIntersection(_li, p10, p11)) throw new Exception("found non-noded intersection at " + p00 + "-" + p01 + " and " + p10 + "-" + p11); }
/// <summary> /// /// </summary> /// <param name="ss0"></param> /// <param name="ss1"></param> private void CheckInteriorIntersections(SegmentString ss0, SegmentString ss1) { IList<Coordinate> pts0 = ss0.Coordinates; IList<Coordinate> pts1 = ss1.Coordinates; for (int i0 = 0; i0 < pts0.Count - 1; i0++) for (int i1 = 0; i1 < pts1.Count - 1; i1++) CheckInteriorIntersections(ss0, i0, ss1, i1); }
private readonly SegmentString _edge; // the parent edge /// <summary> /// Initializes a new instance of the <see cref="SegmentNodeList"/> class. /// </summary> /// <param name="edge">The edge.</param> public SegmentNodeList(SegmentString edge) { _edge = edge; }
NodeVertexIterator(SegmentNodeList nodeList) { _nodeList = nodeList; _edge = nodeList.Edge; _nodeIt = nodeList.GetEnumerator(); }
/// <summary> /// /// </summary> /// <param name="segStr"></param> private void Add(SegmentString segStr) { IList segChains = MonotoneChainBuilder.GetChains(segStr.Coordinates, segStr); foreach(object obj in segChains) { MonotoneChain mc = (MonotoneChain)obj; mc.Id = idCounter++; index.Insert(mc.Envelope, mc); monoChains.Add(mc); } }
/// <summary> /// /// </summary> /// <param name="e0"></param> /// <param name="e1"></param> private void ComputeIntersects(SegmentString e0, SegmentString e1) { IList<Coordinate> pts0 = e0.Coordinates; IList<Coordinate> pts1 = e1.Coordinates; for (int i0 = 0; i0 < pts0.Count - 1; i0++) for (int i1 = 0; i1 < pts1.Count - 1; i1++) SegmentIntersector.ProcessIntersections(e0, i0, e1, i1); }
/// <summary> /// /// </summary> /// <param name="oca"></param> /// <param name="segString"></param> private void Add(OrientedCoordinateArray oca, SegmentString segString) { ocaMap.Add(oca, segString); }
/// <summary> /// /// </summary> /// <param name="oca"></param> /// <param name="segString"></param> /// <returns></returns> private SegmentString FindMatching(OrientedCoordinateArray oca, SegmentString segString) { return (SegmentString)ocaMap[oca]; }
/// <summary> /// Dissolve the given <see cref="SegmentString" />. /// </summary> /// <param name="segString"></param> public void Dissolve(SegmentString segString) { OrientedCoordinateArray oca = new OrientedCoordinateArray(segString.Coordinates); SegmentString existing = FindMatching(oca, segString); if (existing == null) Add(oca, segString); else { if (merger != null) { bool isSameOrientation = CoordinateArrays.Equals(existing.Coordinates, segString.Coordinates); merger.Merge(existing, segString, isSameOrientation); } } }