private bool isLinearEdgeEnabled(PlanarGraphEdge edge, OverlayType operation, Polygon polygon, bool inverseArgs)
{
if (isAreaEdgeEnabled(edge, operation, polygon, inverseArgs))
return false;
switch (operation)
{
case OverlayType.Intersection:
return edge.Label.UsedByObject1 && (edge.Label.UsedByObject2 || polygon.ContainsPoint(edge.CenterPoint()));
case OverlayType.Union:
return edge.Label.UsedByObject1 && !polygon.ContainsPoint(edge.CenterPoint());
case OverlayType.Difference:
return inverseArgs ? false :
edge.Label.UsedByObject1 &&
!polygon.ContainsPoint(edge.CenterPoint()) &&
!edge.Label.UsedByObject2;
case OverlayType.SymmetricDifference:
return edge.Label.UsedByObject1 &&
!polygon.ContainsPoint(edge.CenterPoint()) &&
!edge.Label.UsedByObject2;
}
return false;
}
private bool isAreaEdgeEnabled(PlanarGraphEdge edge, OverlayType operation, Polygon polygon, bool inverseArgs)
{
bool usebyPolyline = edge.Label.UsedByObject1;
bool usebyPolygon = edge.Label.UsedByObject2;
switch (operation)
{
case OverlayType.Intersection:
return false;
case OverlayType.Union:
if (usebyPolygon) return true;
break;
case OverlayType.Difference:
return inverseArgs;
case OverlayType.SymmetricDifference:
if (usebyPolygon) return true;
break;
}
return false;
}
private bool isAreaEdgeEnabled(PlanarGraphEdge edge, OverlayType operation, Polygon p1, Polygon p2)
{
bool usebyPolygon1 = edge.Label.UsedByObject1;
bool usebyPolygon2 = edge.Label.UsedByObject2;
switch (operation)
{
case OverlayType.Intersection:
if (usebyPolygon1 && usebyPolygon2 && edge.OrientationInObject1 == edge.OrientationInObject2)
return true;
if ((usebyPolygon1 ^ usebyPolygon2))
if (usebyPolygon1)
{
if (p2.ContainsPoint(edge.CenterPoint()))
return true;
}
else
{
if (p1.ContainsPoint(edge.CenterPoint()))
return true;
}
break;
case OverlayType.Union:
if (usebyPolygon1 && usebyPolygon2 && edge.OrientationInObject1 == edge.OrientationInObject2)
return true;
if ((usebyPolygon1 ^ usebyPolygon2))
if (usebyPolygon1)
{
if (!p2.ContainsPoint(edge.CenterPoint()))
return true;
}
else
{
if (!p1.ContainsPoint(edge.CenterPoint()))
return true;
}
break;
case OverlayType.Difference:
if (usebyPolygon1 && usebyPolygon2 && edge.OrientationInObject1 != edge.OrientationInObject2)
return true;
if ((usebyPolygon1 ^ usebyPolygon2))
if (usebyPolygon1)
{
if (!p2.ContainsPoint(edge.CenterPoint()))
return true;
}
else
{
if (p1.ContainsPoint(edge.CenterPoint()))
return true;
}
break;
case OverlayType.SymmetricDifference:
if ((usebyPolygon1 ^ usebyPolygon2))
return true;
break;
}
return false;
}
private bool isLinearEdgeEnabled(PlanarGraphEdge edge, OverlayType operation, Polygon p1, Polygon p2)
{
if (isAreaEdgeEnabled(edge, operation, p1, p2))
return false;
switch (operation)
{
case OverlayType.Intersection:
return edge.Label.UsedByObject1 && edge.Label.UsedByObject2;
case OverlayType.Union:
return false;
case OverlayType.Difference:
return false;
case OverlayType.SymmetricDifference:
return false;
}
return false;
}
private void addEdge(PlanarGraphEdge edge)
{
_edges.Add(edge);
}
private void addEdges()
{
List<SplittedSegment> list;
if (_splittedSegmentIndex != null)
{
list = new List<SplittedSegment>();
_splittedSegmentIndex.QueryObjectsInRectangle(_splittedSegmentIndex.IndexedSpace, list);
}
else
list = _splittedSegments;
_edges.Clear();
foreach (SplittedSegment ss in list)
{
//if ((ss.Segment.V1.X == 161.836898803711 &&
// ss.Segment.V2.X == 162.26921081543)
// ||
// (ss.Segment.V2.X == 161.836898803711 &&
// ss.Segment.V1.X == 162.26921081543))
//{
// int a = 1;
//}
PlanarGraphNode node1 = getNodeAt(ref ss.Segment.V1);
PlanarGraphNode node2 = getNodeAt(ref ss.Segment.V2);
if (node1 == null || node2 == null)
throw new InvalidOperationException("Internal error");
if (node1 == node2)
throw new TopologyException();
else
{
PlanarGraphEdge edge = new PlanarGraphEdge(node1, node2);
edge.Label.UsedByObject1 = ss.UsedByObject1;
edge.Label.UsedByObject2 = ss.UsedByObject2;
edge.Label.Object1OccurrencesCount = ss.Object1OccurrencesCount;
edge.Label.Object2OccurrencesCount = ss.Object2OccurrencesCount;
node1.IncidentEdges.Add(edge);
node2.IncidentEdges.Add(edge);
addEdge(edge);
}
}
}
/// <summary>
/// Constructs a contour.
/// </summary>
private Contour processContour(PlanarGraphEdge startEdge,
bool backward)
{
Contour result = new Contour();
PlanarGraphNode startNode = backward ? startEdge.Node2 : startEdge.Node1;
result.Vertices.Add(startNode.Point);
PlanarGraphNode currentNode = backward ? startEdge.Node1 : startEdge.Node2;
result.Vertices.Add(currentNode.Point);
// mark first edge
if ((EdgeUsage)startEdge.Label.Tag != EdgeUsage.None)
{
startEdge.Label.Tag = EdgeUsage.Both;
startEdge.IsVisited = true;
}
else
startEdge.Label.Tag = backward ? EdgeUsage.Backward : EdgeUsage.Forward;
PlanarGraphEdge currentEdge = startEdge;
while (true)
{
List<PlanarGraphEdge> possibleEdges = new List<PlanarGraphEdge>();
foreach (PlanarGraphEdge edge in currentNode.IncidentEdges)
if (edge.Enabled && edge != currentEdge)
{
switch ((EdgeUsage)edge.Label.Tag)
{
case EdgeUsage.Both: break;
case EdgeUsage.None:
possibleEdges.Add(edge);
break;
case EdgeUsage.Forward:
if (edge.Node2 == currentNode)
possibleEdges.Add(edge);
break;
case EdgeUsage.Backward:
if (edge.Node1 == currentNode)
possibleEdges.Add(edge);
break;
}
}
double maxAngle = 0;
Segment previousEdge = new Segment(currentEdge.Node1.Point, currentEdge.Node2.Point);
PlanarGraphEdge targetEdge = null;
if (possibleEdges.Count == 0 && (EdgeUsage)currentEdge.Label.Tag != EdgeUsage.Both)
possibleEdges.Add(currentEdge);
if (possibleEdges.Count == 1)
targetEdge = possibleEdges[0];
else
for (int k = 0; k < possibleEdges.Count; k++)
{
PlanarGraphEdge edge = possibleEdges[k];
Segment kEdge = new Segment(edge.Node1.Point, edge.Node2.Point);
double angle;
try
{
angle = getAngleBetweenEdges(ref previousEdge, ref kEdge, false);
}
catch (ArgumentException)
{
throw new TopologyException();
}
if (angle >= _twoPi)
angle -= _twoPi;
if (angle > maxAngle)
{
maxAngle = angle;
targetEdge = edge;
}
}
if (targetEdge != null)
{
if (targetEdge.Node1.Point.ExactEquals(currentNode.Point))
{
if ((EdgeUsage)targetEdge.Label.Tag == EdgeUsage.None)
targetEdge.Label.Tag = EdgeUsage.Forward;
else
{
targetEdge.Label.Tag = EdgeUsage.Both;
targetEdge.IsVisited = true;
}
result.Vertices.Add((ICoordinate)targetEdge.Node2.Point.Clone());
currentNode = targetEdge.Node2;
}
else
{
if ((EdgeUsage)targetEdge.Label.Tag == EdgeUsage.None)
targetEdge.Label.Tag = EdgeUsage.Backward;
else
{
targetEdge.Label.Tag = EdgeUsage.Both;
targetEdge.IsVisited = true;
}
result.Vertices.Add((ICoordinate)targetEdge.Node1.Point.Clone());
currentNode = targetEdge.Node1;
}
previousEdge = new Segment(targetEdge.Node1.Point, targetEdge.Node2.Point);
currentEdge = targetEdge;
if (currentNode == startNode) // пришли, контур сформирован
{
result.Vertices.RemoveAt(result.Vertices.Count - 1);
break;
}
}
else break;
}
return result;
}